ganglioside gm3 an acidic membrane component that increases

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Proc. Nati. Acad. Sci. U S A Vol. 8 3 , p p . 782-786, February 1986 Medical Sciences Ganglioside GM3: A n acidic membrane component that increases during macrophage-like cell differentiation c a n induce monocytic differentiation o f human myeloid a n d monocytoid leukemic cell lines HL-60 and U937 (ganglioside/differentiation-induction/leukemia) HISAo NoJiiu*, FUMIMARO TAKAKUt, YASUHITO TERUI*, YASUSADA MIURAt, A N D MASAKI SAITO*§ *Division of Hemopoiesis, Institute o f Hematologyand tDepartment o f Hematology, Jichi Medical School, Minami-kawachi-machi, Kawachi-gun, Tochigi-ken, Japan 329-04; a n d tThird Department of Internal Medicine, Faculty ofMedicine, Universityof Tokyo, Hongo, Tokyo, Japan 1 1 3 Communicated by Eugene P . Cronkite, September 1 6 , 1985 ABSTRACT When human myeloid and monocytoid leu- kemic cell lines HL-60 a n d U937, respectively, were treated with an exogenous sialoglycosphingolipid, ganglioside GM3, i n serum-free medium, cell growth was markedly inhibited, a n d their morphological maturation along a monocytic lineage w a s observed. I n addition t o a significant increase i n phagocytic a n d nonspecific esterase activities, marked increase o f monocyte- specific surfaceantigens detectable with monoclonal antibodies such a s OKM1 a n d OKM5 w a s observed i n GM3-fed cells. Other sialoglycosphingolipids with t h e carbohydrate structure belonging t o ganglio-series oligosaccharide, ganglioside G M 1 a n d a brain ganglioside mixture, h a d no effect o n t h e cell differentiation, showing instead stimulatory actions on t h e growth o f these cell lines. W e recently demonstrated that t h e ganglio-series ganglioside G M 3 characteristically increased during macrophage-like cell differentiation o f these cell lines. T h e present results indicate that ganglioside molecular species that specifically increase during monocytic cell differentiation o f human myeloid a n d monocytoid leukemic cell lines m a y play, i n turn, a n important role i n t h e differentiation-nduction of these cell lines along a monocytic cell lineage. Glycosphingolipids (GSLs) a r e ubiquitous membrane com- ponents and have been shown t o b e located almost exclu- sively a t t h e outer leaflet o f plasma membranes (1). Dramatic changes i n G S L composition a n d metabolism have been observed during ontogenesis, differentiation, a n d oncogenic transformation, suggesting a specific role o f membrane GSLs i n regulation o f cell growth a n d cellular interaction (2). GSLs ar e classified into three major series-i.e., ganglio-, globo- a n d lacto-series, according t o their carbohydrate structures. Human promyelocytic leukemia cell line HL-60 cells (3) have been induced t o differentiate into mature granulocytes (4, 5 ) a n d macrophage-like cells ( 6) a n d consist of stem-like cells that a re bipotent with respect to myeloid or macrophage differentiation (7). W e recently demonstrated that HL-60 cells expressed distinct G S L profiles f o r t w o separate path- ways of cell differentiation; ( i ) t h e lacto-series acidic sialo- GSLs, o r lacto-series gangliosides, having longer sugar moieties such a s sialosylnorhexaosylceramide, increased with a concomitant decrease i n t he ganglio-series acidic sialo-GSL, o r ganglio-series ganglioside, G M 3 during gran- ulocytic differentiation; a n d (ii) i n marked contrast t o such changes, ganglio-series ganglioside G M 3 markedly increased with a concurrent decrease i n lacto-series gangliosides in t h e process o f macrophage-like cell differentiation (8). A char- acteristic increase i n ganglio-sefies ganglioside G M 3 w a s also observed during macrophage-like cell differentiation o f other human myeloid a n d monocytic leukemic cell lines such as K562 (9), KG-1 (10), ML-1 (11), a n d U937 (12) (unpublished data). GSLs exogenously added t o t h e cell culture medium a r e incorporated into plasma membranes, resulting i n enrich- ment o f a particular molecular species o f G S L (13-15). Although some o f t h e GSLs could b e released b y trypsin treatment (16), considerable evidence suggests that t h e ceramide moiety o f t h e added GSLs i s inserted i n t h e lipid layer (17, 18). A recent study involving electron spin reso- nance measurements supported this organizational notion (19). I n t h e present study, w e investigated whether G S L molecules that specifically increased during cell tion exhibit a n y physiologicalfunctions i n cell differentiation processes with this approach, a n d w e demonstrated that exogenous ganglioside G M 3 wa s highly potent fordifferen- tiation-induction o f human myeloid and monocytoid leuke- mi c cell lines HL-60 a n d U937 along a monocytic lineage. I t is noteworthy that t h e ganglioside molecular species that characteristically increased during monocytic cell differenti- ation o f human myeloid a n d monocytic leukemic cell lines i n turn could specificallytrigger cell differentiation o f t h e same cell lines along the monocytic cell lineage. MATERIALS A N D METHODS Ganglioside Preparation. G M 3 a n d G M 1 were prepared from d o g erythrocytes a n d bovine brain, respectively, b y solvent partition a n d DEAE-Sephadex chromatography i n o u r laboratory b y th e method o f Momoi e t al. (20). Each ganglioside was found to b e homogenous o n silica gel- precoated high-performance T L C plates (Merck) after devel- opment with chloroform/methanol/0.5% CaCl2 (55:45:10, vol/vol/vol). T h e high-performance TLC plates were sprayed with resorcinol/HCl reagent, a n d gangliosides were visualized b y heating t h e plates a t 95°C a n d were determined quantitatively b y densitometric scanning a s described (8). T h e lipid-bound sialic acid of gangliosides estimated b y t h e resorcinol/HCl method a s modified b y Suzuki (21). A bovine brain ganglioside mixture (Sigma, type I I ) a n d N - acetylneuraminic acid (from Escherichia coli) were pur- chased from Sigma. T h e bovine brain ganglioside mixture consisted o f 7.5% GM1, 2.6% GD3, 56.7% GD1a, 11.5% GD1b, a n d 21.7% GT1b. Abbreviations: GSL, glycosphingolipid; mAb, monoclonal antibody; NapBtOEase, a-napthyl butyrate esterase. T h e glycolipid nomen- clature a n d symbols used a r e from an International Union o f Biochemistry document [(1977) Eur. J . Biochem. 7 9 , 11-21]. § T o whom reprint requests should be addressed. 7 8 2 T h e publication costs o f thisarticle were defrayed i n part by page charge payment. This article must therefore b e hereby marked "advertisement" i n accordance 1 8 U.S.C. §1734 solely t o indicate this fact.

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8/6/2019 Ganglioside GM3 an Acidic Membrane Component That Increases

http://slidepdf.com/reader/full/ganglioside-gm3-an-acidic-membrane-component-that-increases 1/5

P r o c . N a t i . A c a d . S c i . USAV o l . 8 3 , p p . 7 8 2 - 7 8 6 , F e b r u a r y 1 9 8 6M e d i c a l S c i e n c e s

G a n g l i o s i d e G M 3 : An a c i d i c membrane c o m p o n e n t t h a t i n c r e a s e sd u r i n g m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n c a n i n d u c e m o n o c y t i cd i f f e r e n t i a t i o n o f human m y e l o i d a n d m o n o c y t o i d l e u k e m i c c e l ll i n e s H L - 6 0 a n d U 9 3 7

( g a n g l i o s i d e / d i f f e r e n t i a t i o n - i n d u c t i o n / l e u k e m i a )

H I S A o N o J i i u * , FUMIMARO T A K A K U t , Y A S U H I T O T E R U I * , YASUSADA M I U R A t , AND MASAKI S A I T O * §

* D i v i s i o n o f H e m o p o i e s i s , I n s t i t u t e o f H e ma t o l o g y a n d t D e p a r t m e n t o f H e m a t o l o g y , J i c h i M e d i c a l S c h o o l , M i n a m i - k a w a c h i - m a c h i , K a w a c h i - g u n , T o c h i g i - k e n ,J a p a n 3 2 9 - 0 4 ; a n d t T h i r d D e p a r t m e n t o f I n t e r n a l M e d i c i n e , F a c u l t y o f M e d i c i n e , U n i v e r s i t y o f T o k y o , H o n g o , T o k y o, J a p a n 1 1 3

C o m m u n i c a t e d b y E u g e n e P . C r o n k i t e , S e p t e m b e r 1 6 , 1 9 8 5

ABSTRACT When h u m a n m y e l o i d a n d m o n o c y to i d l e u -k e m i c c e l l l i n e s H L - 6 0 a n d U 9 3 7 , r e s p e c t i v e l y , w e r e t r e a t e dw i t h a n e x o g e n o u s s i a l o g l y c o s p h i n g o l i p i d , g a n g l i o s i d e G M 3 , i ns e r u m - f r e e m e d i u m , c e l l g r o w th w a s m a r k e d l y i n h i b i t e d , a n dt h e i r m o r p h o l o g i c a l m a t u r a t i o n a l o n g a m o n o c y t i c l i n e a g e w a so b s e r v e d . I n a d d i t i o n t o a s i g n i f i c a n t i n c r e a s e i n p h a g o c y t i c a n d

n o n s p e c i f i c e s t e r a s e a c t i v i t i e s , m a r k e d i n c r e a s e o f m o n o c y t e -s p e c i f i c s u r f a c e a n t i g e n s d e t e c t a b l e w i t h m o n o c l o n a l a n t i b o d i e ss u c h a s O K M 1 a n d O K M 5 w a s o b s e r v e d i n G M 3 - f e d c e l l s .O t h e r s i a l o g l y c o s p h i n g o l i p i d s w i t h t h e c a r b o h y d r a t e s t r u c t u r eb e l o n g i n g t o g a n g l i o - s e r i e s o l i g o s a c c h a r i d e , g a n g l i o s i d e GM 1a n d a b r a i n g a n g l i o s i d e m i x t u r e , h a d n o e f f e c t o n t h e c e l ld i f f e r e n t i a t i o n , s h o w i n g i n s t e a d s t i m u l a t o r y a c t i o n s o n t h eg r o w t h o f t h e s e c e l l l i n e s . W e r e c e n t l y d e m o n s t r a t e d t h a t t h eg a n g l i o - s e r i e s g a n g l i o s i d e GM 3 c h a r a c t e r i s t i c a l l y i n c r e a s e dd u r i n g m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n o f t h e s e c e l l l i n e s .T h e p r e s e n t r e s u l t s i n d i c a t e t h a t g a n g l i o s i d e m o l e c u l a r s p e c i e st h a t s p e c i f i c a l l y i n c r e a s e d u r i n g m o n o c y t i c c e l l d i f f e r e n t i a t i o no f h u m a n m y e l o i d a n d m o n o c y t o i d l e u k e m i c c e l l l i n e s m a yp l a y , i n t u r n , a n i m p o r t a n t r o l e i n t h e d i f f e r e n t i a t i o n - n d u c t i o no f t h e s e c e l l l i n e s a l o n g a m o n o c y t i c c e l l l i n e a g e .

G l y c o s p h i n g o l i p i d s ( G S L s ) a r e u b i q u i t o u s m e m b r a n e c o m -

p o n e n t s a n d h a v e b e e n s h o w n t o b e l o c a t e d a l m o s t e x c l u -s i v e l y a t t h e o u t e r l e a f l e t o f p l a s m a m e m b r a n e s ( 1 ) . D r a m a t i cc h a n g e s i n GSL c o m p o s i t i o n a n d m e t a b o l i s m h a v e b e e n

o b s e r v e d d u r i n g o n t o g e n e s i s , d i f f e r e n t i a t i o n , a n d o n c o g e n i ct r a n s f o r m a t i o n , s u g g e s t i n g a s p e c i f i c r o l e o f m e m b r a n e G S L si n r e g u l a t i o n o f c e l l g r o w t h a n d c e l l u l a r i n t e r a c t i o n ( 2 ) . G S L sa r e c l a s s i f i e d i n t o t h r e e m a j o r s e r i e s - i . e . , g a n g l i o - , g l o b o -a n d l a c t o - s e r i e s , a c c o r d i n g t o t h e i r c a r b o h y d r a t e s t r u c t u r e s .H u m a n p r o m y e l o c y t i c l e u k e m i a c e l l l i n e H L - 6 0 c e l l s ( 3 ) h a v e

b e e n i n d u c e d t o d i f f e r e n t i a t e i n t o m a t u r e g r a n u l o c y t e s ( 4 , 5 )a n d m a c r o p h a g e - l i k e c e l l s ( 6 ) a n d c o n s i s t o f s t e m - l i k e c e l l st h a t a r e b i p o t e n t w i t h r e s p e c t t o m y e l o i d o r m a c r o p h a g ed i f f e r e n t i a t i o n ( 7 ) . W e r e c e n t l y d e m o n s t r a t e d t h a t H L - 6 0c e l l s

e x p r e s s e dd i s t i n c t GSL

p r o f i l e sf o r t w o

s e p a r a t e p a t h -w a y s o f c e l l d i f f e r e n t i a t i o n ; ( i ) t h e l a c t o - s e r i e s a c i d i c s i a l o -G S L s , o r l a c t o - s e r i e s g a n g l i o s i d e s , h a v i n g l o n g e r s u g a rm o i e t i e s s u c h a s s i a l o s y l n o r h e x a o s y l c e r a m i d e , i n c r e a s e dw i t h a c o n c o m i t a n t d e c r e a s e i n t h e g a n g l i o - s e r i e s a c i d i cs i a l o - G S L , o r g a n g l i o - s e r i e s g a n g l i o s i d e , GM3 d u r i n g g r a n -u l o c y t i c d i f f e r e n t i a t i o n ; a n d ( i i ) i n m a r k e d c o n t r a s t t o s u c h

c h a n g e s , g a n g l i o - s e r i e s g a n g l i o s i d e GM3 m a r k e d l y i n c r e a s e dw i t h a c o n c u r r e n t d e c r e a s e i n l a c t o - s e r i e s g a n g l i o s i d e s i n t h ep r o c e s s o f m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n ( 8 ) . A c h a r -a c t e r i s t i c i n c r e a s e i n g a n g l i o - s e f i e s g a n g l i o s i d e GM 3 w a s a l s o

o b s e r v e d d u r i n g m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n o f o t h e rh u m a n m y e l o i d a n d m o n o c y t i c l e u k e m i c c e l l l i n e s s u c h a sK 5 6 2 ( 9 ) , K G - 1 ( 1 0 ) , M L - 1 ( 1 1 ) , a n d U 9 3 7 ( 1 2 ) ( u n p u b l i s h e dd a t a ) .

G S L s e x o g e n o u s l y a d d e d t o t h e c e l l c u l t u r e m e d i u m a r ei n c o r p o r a t e d i n t o p l a s m a m e m b r a n e s , r e s u l t i n g i n e n r i c h -

m e n t o f a p a r t i c u l a r m o l e c u l a r s p e c i e s o f GSL ( 1 3 - 1 5 ) .A l t h o u g h s o m e o f t h e G S L s c o u l d b e r e l e a s e d b y t r y p s i nt r e a t m e n t ( 1 6 ) , c o n s i d e r a b l e e v i d e n c e s u g g e s t s t h a t t h ec e r a m i d e m o i e t y o f t h e a d d e d G S L s i s i n s e r t e d i n t h e l i p i dl a y e r ( 1 7 , 1 8 ) . A r e c e n t s t u d y i n v o l v i n g e l e c t r o n s p i n r e s o -n a n c e m e a s u r e m e n t s s u p p o r t e d t h i s o r g a n i z a t i o n a l n o t i o n( 1 9 ) . I n t h e p r e s e n t s t u d y , w e i n v e s t i g a t e d w h e t h e r GSLm o l e c u l e s t h a t s p e c i f i c a l l y i n c r e a s e d d u r i n g c e l l d i f f e r e n t i a -t i o n e x h i b i t a n y p h y s i o l o g i c a l f u n c t i o n s i n c e l l d i f f e r e n t i a t i o np r o c e s s e s w i t h t h i s a p p r o a c h , a n d w e d e m o n s t r a t e d t h a te x o g e n o u s g a n g l i o s i d e GM 3 w a s h i g h l y p o t e n t f o r d i f f e r e n -t i a t i o n - i n d u c t i o n o f h u m a n m y e l o i d a n d m o n o c y t o i d l e u k e -m i c c e l l l i n e s H L - 6 0 a n d U 9 3 7 a l o n g a m o n o c y t i c l i n e a g e . I t

i s n o t e w o r t h y t h a t t h e g a n g l i o s i d e m o l e c u l a r s p e c i e s t h a tc h a r a c t e r i s t i c a l l y i n c r e a s e d d u r i n g m o n o c y t i c c e l l d i f f e r e n t i -

a t i o n o f h u m a n m y e l o i d a n d m o n o c y t i c l e u k e m i c c e l l l i n e s i nt u r n c o u l d s p e c i f i c a l l y t r i g g e r c e l l d i f f e r e n t i a t i o n o f t h e s a m ec e l l l i n e s a l o n g t h e m o n o c y t i c c e l l l i n e a g e .

MATERIALS A ND M E T H O D S

G a n g l i o s i d e P r e p a r a t i o n . GM 3 a n d GM 1 w e r e p r e p a r e df r o m d o g e r y t h r o c y t e s a n d b o v i n e b r a i n , r e s p e c t i v e l y , b ys o l v e n t p a r t i t i o n a n d D E A E - S e p h a d e x c h r o m a t o g r a p h y i no u r l a b o r a t o r y b y t h e m e t h o d o f M o m o i e t a l . ( 2 0 ) . E a c h

g a n g l i o s i d e w a s f o u n d t o b e h o m o g e n o u s o n s i l i c a g e l -p r e c o a t e d h i g h - p e r f o r m a n c e TLC p l a t e s ( M e r c k ) a f t e r d e v e l -o p m e n t w i t h c h l o r o f o r m / m e t h a n o l / 0 . 5 % C a C l 2 ( 5 5 : 4 5 : 1 0 ,v o l / v o l / v o l ) . T h e h i g h - p e r f o r m a n c e TLC p l a t e s w e r e

s p r a y e d w i t h r e s o r c i n o l / H C l r e a g e n t , a n d g a n g l i o s i d e s w e r e

v i s u a l i z e d b y h e a t i n g t h e p l a t e s a t 9 5 ° C a n d w e r e d e t e r m i n e dq u a n t i t a t i v e l y b y d e n s i t o m e t r i c s c a n n i n g a s d e s c r i b e d ( 8 ) .T h e l i p i d - b o u n d s i a l i c a c i d o f g a n g l i o s i d e s w a s e s t i m a t e d b yt h e r e s o r c i n o l / H C l m e t h o d a s m o d i f i e d b y S u z u k i ( 2 1 ) . Ab o v i n e b r a i n g a n g l i o s i d e m i x t u r e ( S i g m a , t y p e I I ) a n d N -

a c e t y l n e u r a m i n i c a c i d ( f r o m E s c h e r i c h i a c o l i ) w e r e p u r -c h a s e d f r o m S i g m a . T h e b o v i n e b r a i n g a n g l i o s i d e m i x t u r e

c o n s i s t e d o f 7 . 5 % G M 1 , 2 . 6 % G D 3 , 5 6 . 7 % G D 1 a , 1 1 . 5 %

G D 1 b , a n d 2 1 . 7 % G T 1 b .

A b b r e v i a t i o n s : G S L , g l y c o s p h i n g o l i p i d ; m A b , m o n o c l o n a l a n t i b o d y ;N a p B t O E a s e , a - n a p t h y l b u t y r a t e e s t e r a s e . T h e g l y c o l i p i d n o m e n -c l a t u r e a n d s y m b o l s u s e d a r e f r o m a n I n t e r n a t i o n a l U n i o n o fB i o c h e m i s t r y d o c u m e n t [ ( 1 9 7 7 ) E u r . J . B i o c h e m . 7 9 , 1 1 - 2 1 ] .§ T o whom r e p r i n t r e q u e s t s s h o u l d b e a d d r e s s e d .

7 8 2

T h e p u b l i c a t i o n c o s t s o f t h i s a r t i c l e w e r e d e f r a y e d i n p a r t b y p a g e c h a r g ep a y m e n t . T h i s a r t i c l e m u s t t h e r e f o r e b e h e r e b y m a r k e d " a d v e r t i s e m e n t "

i n a c c o r d a n c e w i t h 1 8 U . S . C . § 1 7 3 4 s o l e l y t o i n d i c a t e t h i s f a c t .

8/6/2019 Ganglioside GM3 an Acidic Membrane Component That Increases

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P r o c . N a t l . A c a d . S c i . USA 8 3 ( 1 9 8 6 ) 7 8 3

C e l l C u l t u r e . C e l l s o f h u m a n p r o m y e l o c y t i c l e u k e m i a c e l ll i n e H L - 6 0 ( 3 ) a n d h u m a n m o n o c y t i c l e u k e m i c c e l l l i n e U 9 3 7( 1 2 ) w e r e g r o w n i n F a l c o n 3 0 2 4 t i s s u e c u l t u r e f l a s k s ( B e c t o nD i c k i n s o n L a b w a r e , O x n a r d , C A ) i n a s e r u m - f r e e s y n t h e t i cm e d i u m c o m p o s e d o f e q u a l v o l u m e s o f D u l b e c c o ' s m o d i f i e dE a g l e ' s m i n i m a l e s s e n t i a l m e d i u m a n d H a m ' s F - 1 2 m e d i u ms u p p l e m e n t e d w i t h 3 0 nM s e l e n i u m d i o x i d e , 1 . 2 g o f s o d i u mb i c a r b o n a t e p e r l i t e r , 1 5 mM H e p e s ( p H 7 . 2 ) , 5 U g o f i n s u l i n

p e r m l ( S i g m a ) , a n d 5 p u g o f t r a n s f e r r i n ( S i g m a ) p e r m l( D M E / F 1 2 m e d i u m ) a c c o r d i n g t o t h e m e t h o d d e s c r i b e d b yB r e i t m a n e t a l . ( 2 2 ) a t 3 7 0 C i n h u m i d i f i e d 5% c a r b o nd i o x i d e / 9 5 % a i r . C e l l c o u n t s w e r e m a d e w i t h a h e m o c y t o m -e t e r , a n d v i a b i l i t y w a s a s s e s s e d b y e r y t h r o s i n e B d y e e x c l u -s i o n . P u r i f i e d g a n g l i o s i d e s w e r e a d d e d t o t h e c e l l c u l t u r em e d i u m e s s e n t i a l l y a s d e s c r i b e d b y B r e m e r e t a l . ( 2 3 ) .B r i e f l y , a g a n g l i o s i d e w a s d i s s o l v e d i n a n a p p r o p r i a t e v o l u m eo f w a t e r w i t h t h e a i d o f s o n i c a t i o n , s t e r i l i z e d b y p a s s a g et h r o u g h a s t e r i l i z e d 0 . 2 2 - , u m M i l l i p o r e f i l t e r , a n d q u a n t i t a t e db y t h e r e s o r c i n o l H C l m e t h o d . T h i s s o l u t i o n w a s d i l u t e d w i t ha n e q u a l v o l u m e o f DME/F12 m e d i u m o f 2 - f o l d c o n c e n t r a -t i o n t o 1 mM a n d w a s a d d e d t o t h e c u l t u r e m e d i u m t o t h ed e s i r e d g a n g l i o s i d e c o n c e n t r a t i o n .

E v a l u a t i o n o f C e l l D i f f e r e n t i a t i o n . C e l l d i f f e r e n t i a t i o n o fH L - 6 0 a n d U 9 3 7 c e l l s t r e a t e d w i t h e x o g e n o u s l y a d d e d

g a n g l i o s i d e s w a s a s s e s s e d m o r p h o l o g i c a l l y , c y t o c h e m i c a l l y ,a n d f u n c t i o n a l l y . F o r m o r p h o l o g i c a l a s s e s s m e n t o f t h e c e l l s ,C y t o s p i n s l i d e p r e p a r a t i o n s w e r e p r e p a r e d u s i n g a S h a n d o nC y t o s p i n c e n t r i f u g e ( S h a n d o n S o u t h e r n P r o d u c t s , C h e s h i r e ,E n g l a n d ) a n d s t a i n e d w i t h W r i g h t - G i e m s a s t a i n i n g s o l u t i o n .F o r c y t o c h e m i c a l a s s e s s m e n t o f c e l l d i f f e r e n t i a t i o n , n o n s p e -c i f i c e s t e r a s e a c t i v i t y w a s d e t e r m i n e d c y t o c h e m i c a l l y b y t h ee s t e r a s e d o u b l e - s t a i n i n g m e t h o d f o r a - n a p h t h y l b u t y r a t ee s t e r a s e ( N a p B t O E a s e ) a n d n a p h t h o l A S - D - c h l o r o a c e t a t ee s t e r a s e a s d e s c r i b e d b y L i e t a l . ( 2 4 ) . F u n c t i o n a l d i f f e r e n -t i a t i o n w a s a s s e s s e d o n t h e b a s i s o f p h a g o c y t i c a c t i v i t y o f t h ec e l l s . P h a g o c y t i c a c t i v i t y o f u n d i f f e r e n t i a t e d a n d d i f f e r e n t i -a t i o n - i n d u c e d c e l l s w a s m e a s u r e d b y c o u n t i n g t h e n u m b e r o fc e l l s t h a t p h a g o c y t o s e d l a t e x o r y e a s t p a r t i c l e s a s d e s c r i b e d( 2 5 ) . P o l y s t y r e n e l a t e x p a r t i c l e s ( D o w C h e m i c a l , I n d i a n a p o -

l i s ; 1 . 0 9 - , u m d i a m e t e r ) w e r e a d d e d t o t h e c e l l s u s p e n s i o n i nRPMI 1 6 4 0 m e d i u m a n d w e r e l e f t i n c o n t a c t w i t h t h e c e l l s f o r6 0 m i n a t 3 7 ° C . T h e f i n a l c o n c e n t r a t i o n s w e r e 1 x 1 0 1 0 l a t e xp a r t i c l e s p e r m l a n d 0 . 5 - 1 x 1 0 6 c e l l s p e r m l , r e s p e c t i v e l y .C e l l s i n g e s t i n g m o r e t h a n f i v e l a t e x p a r t i c l e s w e r e c o n s i d e r e dt o b e c e l l s c a p a b l e o f p h a g o c y t o s i s , a n d a t l e a s t 2 0 0 v i a b l ec e l l s w e r e e x a m i n e d i n e a c h e x p e r i m e n t a l g r o u p . F o r t h ey e a s t - p h a g o c y t o s i s a s s a y , y e a s t p a r t i c l e s ( S a c c h a r o m y c e sc e r e v i s i a e ; S i g m a ) w e r e a d d e d t o t h e c e l l s u s p e n s i o n i nH a n k s ' b a l a n c e d s a l t s o l u t i o n ( H B S S ) c o n t a i n i n g 5% f r e s hh u m a n s e r u m a n d w e r e l e f t i n c o n t a c t w i t h t h e c e l l s f o r 3 0 m i na t 3 7 ° C . T h e f i n a l c o n c e n t r a t i o n s w e r e 6 . 2 5 x 1 0 7 y e a s tp a r t i c l e s p e r m l a n d 2 . 5 x 1 0 6 c e l l s p e r m l , r e s p e c t i v e l y . A f t e rw a s h i n g o u t t h e r e m a i n i n g y e a s t p a r t i c l e s , t h e c e l l s w e r es t a i n e d w i t h Z i e h l ' s c a r b o l f u c h s i n s o l u t i o n : 1 v o l o f a 1 1 %f u c h s i n s o l u t i o n i n e t h a n o l a n d 1 0 v o l o f 5% p h e n o l i n d i s t i l l e dw a t e r w e r e m i x e d a n d t h e n d i l u t e d 1 : 1 0 w i t h HBSS t o o b t a i nw o r k i n g Z i e h l ' s c a r b o l f u c h s i n s o l u t i o n . T h e y e a s t p a r t i c l e so u t s i d e t h e c e l l s w e r e s t a i n e d r e d , a n d t h e y e a s t p a r t i c l e sc o m p l e t e l y i n g e s t e d b y t h e c e l l s w e r e p r e v e n t e d f r o m t a k i n gu p t h e s t a i n . T h e c e l l s c o n t a i n i n g u n s t a i n e d y e a s t p a r t i c l e sw e r e c o n s i d e r e d t o b e c e l l s c a p a b l e o f p h a g o c y t o s i s , a n d a tl e a s t 2 0 0 v i a b l e c e l l s w e r e e x a m i n e d i n e a c h e x p e r i m e n t a lg r o u p .

R e a c t i v i t y w i t h M o n o c l o n a l A n t i b o d i e s . R e a c t i v i t y o f t h eu n t r e a t e d a n d G M 3 - t r e a t e d c e l l s w i t h v a r i o u s m o n o c l o n a la n t i b o d i e s ( m A b s ) w a s i n v e s t i g a t e d b y f l o w c y t o m e t r y . T h emAbs u s e d w e r e : OKB2 ( 2 6 ) , a n I g G 1 a n t i b o d y t h a t r e a c t s

w i t h h u m a n g r a n u l o c y t e s a n d B l y m p h o c y t e s ; O K M 1 ( 2 7 ) , a n

I g G 2 b a n t i b o d y t h a t r e a c t s w i t h h u m a n b l o o d m o n o c y t e s a n dg r a n u l o c y t e s ; a n d O K M 5 ( 2 8 ) , a n I g G 1 a n t i b o d y t h a t r e a c t s

w i t h h u m a n m o n o c y t e s a n d p l a t e l e t s ( O r t h o D i a g n o s t i c s ) .A n t i g e n e x p r e s s i o n w i t h mAbs w a s q u a n t i f i e d b y t h e i n d i r e c ti m m u n o f l u o r e s c e n c e m e t h o d w i t h c y t o f l u o r o m e t r y i n O r t h oS p e c t r u m I I I ( O r t h o D i a g n o s t i c s ) a s d e s c r i b e d b y T a l l e e t a l .( 2 8 ) .

RESULTS

E f f e c t o f E x o g e n o u s l y A d d e d G a n g l i o s i d e s o n C e l l G r o w t ha n d C e l l D i f f e r e n t i a t i o n o f H L - 6 0 a n d U 9 3 7 C e l l s . T h e e f f e c to f e x o g e n o u s l y a d d e d g a n g l i o s i d e s o n t h e g r o w t h o f H L - 6 0a n d U 9 3 7 c e l l s w a s e x a m i n e d . When H L - 6 0 c e l l s w e r e

c u l t u r e d w i t h 5 0 n m o l o f e x o g e n o u s g a n g l i o s i d e GM 3 p e r m l ,c e l l g r o w t h w a s c o m p l e t e l y i n h i b i t e d . H o w e v e r , o t h e rg a n g l i o - s e r i e s g a n g l i o s i d e s , GM 1 a n d a b o v i n e b r a i ng a n g l i o s i d e m i x t u r e , s h o w e d i n s t e a d a s t i m u l a t o r y a c t i o n o nc e l l g r o w t h , a n d f r e e N - a c e t y l n e u r a m i n i c a c i d h a d n o e f f e c to n c e l l g r o w t h a t t h e s a m e c o n c e n t r a t i o n ( F i g . 1 L e f t ) . S i m i l a re f f e c t s o f e x o g e n o u s g a n g l i o s i d e s w e r e o b s e r v e d o n U 9 3 7c e l l s ( F i g . 1 R i g h t ) . T h e i n h i b i t i o n o f g r o w t h o f H L - 6 0 c e l l sb y GM3 w a s a c c o m p a n i e d b y s t r i k i n g c h a n g e s i n t h e m o r -

p h o l o g i c a l c h a r a c t e r i s t i c s o f m o n o c y t i c d i f f e r e n t i a t i o n . A f t e r6 d a y s o f c u l t u r e , W r i g h t - G i e m s a s t a i n i n g o f C y t o s p i n c e l lp r e p a r a t i o n s r e v e a l e d t h e l o s s o f c y t o p l a s m i c b a s o p h i l i a ,l o b u l a t i o n o f n u c l e i , a n d s o m e w h a t v a c u o l a t e d c y t o p l a s m sw i t h r u f f l e d s u r f a c e m e m b r a n e s , s u g g e s t i n g t h e d i f f e r e n t i a -t i o n i n t o m o n o c y t i c m a t u r e c e l l s ( F i g . 2 B ) . A b o u t 2 0 % o f t h eu n t r e a t e d c e l l s c u l t u r e d i n s e r u m - f r e e m e d i u m e x h i b i t e dw e a k N a p B t O E a s e a c t i v i t y , a l t h o u g h o n l y 3% o f t h e o r i g i n a lc e l l s c u l t u r e d i n RPMI 1 6 4 0 m e d i u m s u p p l e m e n t e d w i t h 1oh e a t - i n a c t i v a t e d f e t a l c a l f s e r u m d i d s o ( F i g . 2 C ) . WhenH L - 6 0 c e l l s w e r e c u l t u r e d w i t h e x o g e n o u s l y a d d e d G M 3 , t h en u m b e r o f N B E - p o s i t i v e c e l l s r e m a r k a b l y i n c r e a s e d i n a

t i m e - d e p e n d e n t m a n n e r , a n d t h e d e g r e e o f N a p B t O E a s es t a i n i n g w a s m u c h m o r e i n t e n s i v e ( F i g s . 2 D a n d 3 ) . T h i se s t e r a s e a c t i v i t y w a s c o m p l e t e l y i n h i b i t e d b y N a F , i n d i c a t i n gt h e s p e c i f i c i t y f o r t h e m o n o c y t i c l i n e a g e . H o w e v e r , o t h e rg a n g l i o - s e r i e s g a n g l i o s i d e s a n d f r e e N - a c e t y l n e u r a m i n i c a c i dh a d n o e f f e c t o n t h e n u m b e r o f N a p B t O E a s e - p o s i t i v e c e l l s( F i g . 3 ) . T h e i n h i b i t i o n o f g r o w t h o f U 9 3 7 c e l l s b y GM 3 w a s

a l s o a c c o m p a n i e d b y m o r p h o l o g i c a l c h a n g e s c o n s i s t e n t w i t h

1 4 1 4

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6 ~ ~ ~ ~ ~ ~ ~ 6

4 ~ ~ ~ ~ ~ ~ ~ 4

12 3 4 56 7 1 2 3 4 5 6 7

T i m e i n c u l t u r e , d a y s

F I G . 1 . E f f e c t o f e x o g e n o u s l y a d d e d g a n g l i o s i d e s o n c e l l g r o w t ho f H L - 6 0 a n d U 9 3 7 c e l l s . H L - 6 0 ( L e f t ) a n d U 9 3 7 ( R i g h t ) c e l l s w e r es e e d e d i n t o F a l c o n 3 0 2 4 t i s s u e c u l t u r e f l a s k s a t a n i n i t i a l c o n c e n t r a -t i o n o f 1 . 5 x 1 0 5 c e l l s p e r m l a n d g r o w n i n s e r u m - f r e e h o r m o n a l l yd e f i n e d DME/F12 m e d i u m c o n t a i n i n g n o g a n g l i o s i d e s ( o ) , 5 0 1 u MN - a c e t y l n e u r a m i n i c a c i d ( e ) , 5 0 , u M GM 3 ( A ) , 5 0 , g M GM 1 ( A ) , o r 5 0, u M b o v i n e b r a i n g a n g l i o s i d e m i x t u r e ( c ) . C e l l c o u n t i n g w a s p e r -f o r m e d w i t h a h e m o c y to m e t e r , a n d v i a b i l i t y w a s c h e c k e d b y t h ee r y t h r o s i n e B d y e - e x c l u s i o n t e s t . E a c h d a t a p o i n t r e p r e s e n t s t h em e a n o f t h r e e d e t e r m i n a t i o n s . S t a n d a r d d e v i a t i o n s w e r e < 1 0 % o . T h ev i a b i l i t y w a s > 9 0 % o i n e a c h g r o u p t h r o u g h o u t t h e c u l t u r e p e r i o d s .

M e d i c a l S c i e n c e s : N o j i r i e t a l .

8/6/2019 Ganglioside GM3 an Acidic Membrane Component That Increases

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7 8 4 M e d i c a l S c i e n c e s : N o j i r i e t a l .

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t h e i n d u c t i o n o f a m o n o c y t e - m a c r o p h a g e p h e n o t y p e ( F i g . 4 ) .G M 3 - t r e a t e d U 9 3 7 c e l l s w e r e c h a r a c t e r i z e d b y a n i n c r e a s e i nc e l l s i z e , a d e c r e a s e i n t h e n u c l e a r / c y t o p l a s m i c r a t i o , a p a l e rc y t o p l a s m , m o r e p r o m i n e n t g r a n u l e s , a n d a g r e a t e r d e g r e e o f

v a c u o l i z a t i o n i n t h e c y t o p l a s m ( F i g . 4 B ) . A l t h o u g h U 9 3 7 c e l l sw e r e o r i g i n a l l y p o s i t i v e a s t o N a p B t O E a s e s t a i n i n g , t h eG M 3 - t r e a t e d c e l l s w e r e s t a i n e d m o r e s t r o n g l y f o r N a p B t O E -a se a c t i v i t y ( F i g s . 4 C a n d D ) . T h i s N a p B t O E a s e a c t i v i t y w a s

a l s o c o m p l e t e l y i n h i b i t e d b y N a F . O t h e r g a n g l i o - s e r i e sg a n g l i o s i d e s a n d f r e e N - a c e t y l n e u r a m i n i c a c i d h a d no e f f e c to n t h e m o r p h o l o g y or N a p B t O E a s e s t a i n i n g i n t e n s i t y . I n

a d d i t i o n t o m o r p h o l o g i c a l d i f f e r e n t i a t i o n , H L - 6 0 a n d U 9 3 7

c e l l s t r e a t e d w i t h GM 3 s h o w e d f u n c t i o n a l d i f f e r e n t i a t i o n -i . e . , a s i g n i f i c a n t i n c r e a s e i n t h e c a p a c i t y t o p h a g o c y t o s e

l a t e x or y e a s t p a r t i c l e s ( F i g . 5 ) .C h a n g e s o f C e l l - S u r f a c e P h e n o t y p e s I n d u c e d b y E x o g e n o u s

G a n g l i o s i d e s . C h a n g e s o f t h e c e l l - s u r f a c e a n t i g e n s o n H L - 6 0

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T i m e i n c u l t u r e , d a y s

F I G . 3 . E f f e c t o f e x o g e n o u s l y a d d e d g a n g l i o s i d e s o n c e l l d i f f e r -e n t i a t i o n o f H L - 6 0 c e l l s . H L - 6 0 c e l l s w e r e s e e d - d a t a n i n i t i a lc o n c e n t r a t i o n o f 1 . 5 x 1 0 i c e l l s pe r m l a n d g rown i t h e s e r u m - f r e e

DME/F12 medium c o n t a i n i n g no g a n g l i o s i d e s ( o ) , 5 0 , u M N - a c e t y l -n e u r a m i n i c a c i d ( e ) , 5 0 , u M GM 3 ( A ) , 5 0 1 u M GM 1 ( A ) , or 5 0 I A Mb o v i n e b r a i n g a n g l i o s i d e m i x t u r e ( n ) . D i f f e r e n t i a t i o n w a s d e t e r m i n e d

o n t h e b a s i s o f t h e i n d u c t i o n o f N a p B t O E a s e a c t i v i t y . Th e n u m b e ro f N a p B t O E a s e - p o s i t i v e c e l l s w a s d e t e r m i n e d o n d a y s 3 a n d 6 o f

c u l t u r e . E a c h p o i n t r e p r e s e n t s t h e a v e r a g e o f t h r e e d e t e r m i n a t i o n s ,a n d v e r t i c a l b a r s s h o w s t a n d a r d d e v i a t i o n s .

F I G . 2 . D i f f e r e n t i a t i o n - i n d u -c t i o n o f H L - 6 0 c e l l s i n t o m o n o -c y t i c m a t u r e c e l l s w i t h e x o g e n o u s -

..l y a d d e d G M 3 . ( A ) U n t r e a t e dH L - 6 0 c e l l s c u l t u r e d i n t h e s e r u m -

f r e e m e d i u m f o r 6 d a y s . ( W r i g h t -G i e m s a s t a i n . ) ( B ) H L - 6 0 c e l l s c u l -t u r e d i n t h e s e r u m - f r e e m e d i u mw i t h 5 0 AM e x o g e n o u s l y a d d e dGM3 f o r 6 d a y s . ( W r i g h t - G i e m s as t a i n . ) ( C ) N a p B t O E a s e s t a i n i n go f u n t r e a t e d H L - 6 0 c e l l s c u l t u r e di n t h e s e r u m - f r e e m e d i u m f o r 6d a y s . ( D ) N a p B t O E a s e s t a i n i n g o fH L - 6 0 c e l l s t r e a t e d w i t h 5 0 A i M

e x og e n o u s ly added GM3 fo r 6

d a y s . ( O r i g i n a l m a g n i f i c a t i o nx S o o f o r A a n d B a n d X 2 5 0 f o r Ca n d D ; r e p r o d u c e d a t 7 5 % o fo r i g i n a l .

a n d U 9 3 7 c e l l s c a u s e d b y e x o g e n o u s l y a d d e d g a n g l i o s i d e sw e r e e v a l u a t e d b y c y t o f l u o r o g r a p h y . T h e t r e a t m e n t o f H L - 6 0c e l l s w i t h 5 0 , u M e x o g e n o u s GM 3 f o r 6 d a y s r e s u l t e d i n a

m a r k e d i n c r e a s e i n m o n o c y t e - s p e c i f i c a n t i g e n s d e t e c t a b l ew i t h mAbs s u c h a s O K M 1 a n d O K M 5 w i t h a c o n c o m i t a n td e c r e a s e i n g r a n u l o c y t e - s p e c i f i c e p i t o p e r e c o g n i z e d b y t h em A b O K B2 ( T a b l e 1 ) . M a r k e d i n c r e a s e s i n t h e r e a c t i v i t y w i t hm o n o c y t e - s p e c i f i c mAbs O K M 1 a n d O K M 5 a n d t h e m e a nf l u o r e s c e n t i n t e n s i t y o f t h e p o s i t i v e c e l l s w e r e a l s o o b s e r v e di n G M 3 - t r e a t e d U 9 3 7 c e l l s ( T a b l e 1 ) . No s i g n i f i c a n t c h a n g e si n t h e c e l l - s u r f a c e p h e n o ty p e s w e r e o b s e r v e d i n H L - 6 0 a n dU 9 3 7 c e l l s t r e a t e d w i t h o t h e r g a n g l i o - s e r i e s g a n g l i o s i d e s o r

f r e e N - a c e t y l n e u r a m i n i c a c i d .D o s e - D e p e n d e n t E f f e c t o f E x o g e n o u s GM 3 o n C e l l G r o w t h

a n d C e l l D i f f e r e n t i a t i o n o f H L - 6 0 C e l l s . When H L - 6 0 c e l l sw e r e c u l t u r e d w i t h v a r i o u s c o n c e n t r a t i o n o f G M 3 , c e l lg r o w t h w a s s u p p r e s s e d i n a d o s e - d e p e n d e n t m a n n e r ( F i g . 6

L e f t ) . W i t h 5 0 ,M G M 3 , c e l l g r o w t h w a s c o m p l e t e l y i n h i b -i t e d . A f t e r 6 d a y s o f i n c u b a t i o n w i t h v a r i o u s c o n c e n t r a t i o n so f e x o g e n o u s G M 3 , t h e p e r c e n t a g e o f N a p B t O E a s e - p o s i t i v ec e l l s a l s o v a r i e d i n a d o s e - d e p e n d e n t m a n n e r , r e a c h i n g a

m a x i m u m o f 8 4 . 8 % a t 5 0 , A M ( F i g . 6 R i g h t ) . D u r i n g t h ec u l t u r e p e r i o d , H L - 6 0 c e l l s c o n s t a n t l y e x h i b i t e d a v i a b i l i t y o f> 9 0 % o , i n d i c a t i n g t h a t t h e s u p p r e s s i v e e f f e c t o f GM 3 o n c e l lg r o w t h w a s n o t d u e t o a c y t o t o x i c e f f e c t b u t w a s d u e t o a n

i n h i b i t i o n o f t h e p r o l i f e r a t i o n o f t h e l e u k e m i c c e l l s b y t h ee n f o r c e d d i f f e r e n t i a t i o n t o p o s t m i t o t i c c e l l s . T h e h i g h p e r -c e n t a g e o f v i a b l e c e l l s a l s o e l i m i n a t e d t h e p o s s i b i l i t y t h a t a l lo r m a j o r p a r t o f t h e G M 3 - i n d u c e d d i f f e r e n t i a t i o n w a s a r e s u l to f s e l e c t i v e e n r i c h m e n t f o r d i f f e r e n t i a t e d c e l l s .

DISCUSSION

A s t o t h e GSL c o m p o s i t i o n o f h u m a n m y e l o i d l e u k e m i c c e l l s ,we h a v e r e p o r t e d a s f o l l o w s : ( i ) l e u k e m i c b l a s t c e l l s e x h i b i ts i m p l e GSL p r o f i l e s w i t h s h o r t - s u g a r - c h a i n GSL s p e c i e s ,s u c h a s c e r a m i d e m o n o h e x o s i d e a n d g a n g l i o s i d e G M 3 , a sm a j o r c o m p o n e n t s , ( i i ) t h e m a j o r GSL c o m p o n e n t o f n o r m a lm a t u r e c e l l s w a s c o n s i d e r a b l y r e d u c e d i n t h e l e u k e m i c c e l l s ;a n d ( i i i ) t h e GSL c o n t e n t o f t h e l e u k e m i c c e l l s was m u c hl o w e r t h a n t h a t o f n o r m a l m a t u r e c e l l s ( 8 , 2 9 ) . S i m i l a r r e s u l t sa l s o h a v e b e e n r e p o r t e d b y M a c h e r e t a l . ( 3 0 ) . Whenl e u k e m i c c e l l s w e r e i n d u c e d t o d i f f e r e n t i a t e i n t o m a t u r e c e l l s ,a d r a s t i c c h a n g e i n t h e GSL c o m p o s i t i o n w a s o b s e r v e d ,i n d i c a t i n g t h a t t h e G S L - p r o f i l e s w e r e d i f f e r e n t i a t i o n - a s s o -

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P r o c . N a t l . A c a d . S c i . U S A 8 3 ( 1 9 8 6 ) 7 8 5

F I G . 4 . D i f f e r e n t i a t i o n - i n d u c t i o n o f

U 9 3 7 c e l l s i n t o m o n o c y t i c m a t u r e c e l l sw i t h e x o g e n o u s l y a d d e d GM3. ( A ) U n -

t r e a t e d U 9 3 7 c e l l s c u l t u r e d i n t h e s e r u m -

f r e e m e d i u m f o r 6 d a y s . ( W r i g h t - G i e m s as t a i n . ) ( B ) U 9 3 7 c e l l s c u l t u r e d i n t h es e r u m - f r e e m e d i u m w i t h 5 0 uM e x o g e -

n o u s l y a d d e d GM 3 f o r 6 d a y s . ( W r i g h t -G i e m s a s t a i n . ) ( C ) N a p B t O E a s e s t a i n i n go f u n t r e a t e d U 9 3 7 c e l l s c u l t u r e d i n t h es e r u m - f r e e medium f o r 6 d a y s . ( D )

N a p B t O E a s e s t a i n i n g o f U 9 3 7 c e l l s t r e a t -e d w i t h 5 0 , i M GM 3 f o r 6 d a y s . ( O r i g i n a lm a g n i f i c a t i o n x 5 0 0 f o r A a n d B a n d x 2 5 0

f o r C a n d D ; r e p r o d u c e d a t 7 5 % o f

o r i g i n a l . )

c i a t e d p h e n o t y p e s i n l e u k e m i c c e l l s . H L - 6 0 c e l l s , w h i c h a r e

b i p o t e n t w i t h r e s p e c t t o t h e m y e l o i d o r m o n o c y t i c p a t h w a yo f d i f f e r e n t i a t i o n , e x h i b i t e d d i s t i n c t q u a n t i t a t i v e c h a n g e s i nt h e GS L c o m p o s i t i o n , d e p e n d i n g n o t o n l y o n t h e d i f f e r e n t i -a t i o n s t a g e b u t a l s o o n t h e d i f f e r e n t i a t i o n d i r e c t i o n ( 8 ) . Ar e m a r k a b l e i n c r e a s e i n g a n g l i o - s e r i e s g a n g l i o s i d e GM 3 w i t h a

c o n c o m i t a n t d e c r e a s e i n l a c t o - s e r i e s g a n g l i o s i d e s w a s o b -

s e r v e d i n t h e p r o c e s s o f m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n( 8 ) . A m a r k e d i n c r e a s e i n g a n g l i o s i d e GM 3 w a s a l s o o b s e r v e d

d u r i n g m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n o f o th e r hum an

n o n l y m p h o i d l e u k e m i a c e l l l i n e s , K 5 6 2 , K G - 1 , M L - 1 , a n d

U 9 3 7 ( u n p u b l i s h e d d a t a ) , s u g g e s t i n g t h e p r e s e n c e o f a c o m -

m on m e c h a n i s m f o r m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o n o f

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F I G . 5 . E f f e c t o f e x o g e n o u s l y a d d e d g a n g l i o s i d e s o n p h a g o c y t i ca c t i v i t y o f H L - 6 0 ( m ) a n d U 9 3 7 ( m ) c e l l s . H L - 6 0 a n d U 9 3 7 c e l l s ( 2 . 0x 1 0 - c e l l s p e r m l ) i n DME/F12 s e r u m - f r e e m e d i u m w e r e i n c u b a t e d

w i t h o r w i t h o u t 5 0 , u M e x o g e n o u s g a n g l i o s i d e s f o r 6 d a y s a n d t h e n

w e r e a s s a y e d f o r p h a g o c y t i c a c t i v i t y a g a i n s t l a t e x ( L e f t ) a n d y e a s t( R i g h t ) p a r t i c l e s . P h a g o c y t i c a c t i v i t y i s e x p r e s s e d a s t h e p e r c e n t a g e

o f c e l l s i n g e s t i n g l a t e x o r y e a s t p a r t i c l e s . C o l u m n s r e p r e s e n t m e a n s

o f d u p l i c a t e e x p e r i m e n t s , e a c h o f w h i c h i n c l u d e d t r i p l e r e p l i c a t e s .V e r t i c a l b a r s o n c o l u m n s s h o w s t a n d a r d d e v i a t i o n s , w h i c h w e r e

< 1 0 % o . BBGM, b o v i n e b r a i n g a n g l i o s i d e m i x t u r e ; N e u A c , N - a c e t y l -n e u r a m i i c a c i d .

b i o l o g i c a l i m p l i c a t i o n s o f g l y c o l i p i d c h a n g e s i n a s s o c i a t i o nw i t h h e m a t o p o i e t i c c e l l d i f f e r e n t i a t i o n h a v e r e m a i n e d u n -

c l e a r .I t h a s b e e n r e p o r t e d t h a t GSLs e x o g e n o u s l y a d d e d t o t h e

c e l l c u l t u r e medium w e r e i n c o r p o r a t e d i n t o p l a s m a m e m -b r a n e s , r e s u l t i n g i n e n r i c h m e n t o f a s p e c i f i c t y p e o f m e m -b r a n e g l y c o l i p i d ( 1 3 - 1 5 ) . On t h e b a s i s o f t h e f a c t t h a t c h a n g e si n t h e GSL c o m p o s i t i o n a r e c l o s e l y a s s o c i a t e d w i t h t h e

i n d u c t i o n o f l e u k e m i c c e l l d i f f e r e n t i a t i o n , o u r m a i n a i m i n t h e

p r e s e n t s t u d y w a s t o i n v e s t i g a t e w h e t h e r l e u k e m i c c e l l sw o u l d d i f f e r e n t i a t e i n t o f u n c t i o n a l m a t u r e c e l l s when GSLm o l e c u l a r s p e c i e s t h a t a r e r e d u c e d i n l e u k e m i c c e l l s w e r e

s u p p l e m e n t e d . I n t h e p r e s e n t s t u d y , we d e m o n s t r a t e d t h a tHL-60 a n d U937 c e l l s w e r e s p e c i f i c a l l y i n d u c e d b ye x o g e n o u s l y a d d e d GM 3 t o d i f f e r e n t i a t e m o r p h o l o g i c a l l y a n d

f u n c t i o n a l l y i n t o m o n o c y t i c m a t u r e c e l l s , t h e i r g r o w t h b e i n gm a r k e d l y s u p p r e s s e d , a n d t h a t o t h e r g a n g l i o - s e r i e s g a n g l i o -s i d e s a n d f r e e N - a c e t y l n e u r a m i n i c a c i d w e r e i n a c t i v e a s t o

t h e m o n o c y t i c d i f f e r e n t i a t i o n . T h e s e f i n d i n g s a r e o f g r e a ti n t e r e s t b e c a u s e t h e g a n g l i o s i d e m o l e c u l a r s p e c i e s t h a t s p e -c i f i c a l l y i n c r e a s e s d u r i n g m a c r o p h a g e - l i k e c e l l d i f f e r e n t i a t i o no f H L - 6 0 a n d U 9 3 7 c e l l s i n d u c e d b y c h e m i c a l a g e n t s c a n

t r i g g e r t h e m o n o c y t i c c e l l d i f f e r e n t i a t i o n o f t h e s e c e l l l i n e s .T h e p r e s e n t r e s u l t s s u g g e s t t h a t s u c h a m a r k e d i n c r e a s e o f

GM 3 c o n s t i t u t e s n o t m e r e l y t h e m o n o c y t i c c e l l d i f f e r e n t i a -t i o n - a s s o c i a t e d p h e n o t y p e b u t a l s o m ay p l a y a n i m p o r t a n t

T a b l e 1 . E x p r e s s i o n o f c e l l s u r f a c e m a r k e r s o n H L - 6 0 a n d U 9 3 7

c e l l s a f t e r t r e a t m e n t w i t h GM 3

GM 3t r e a t - % p o s i t i v e c e l l s

C e l l s m e n t O K B 2 O K M 1 O K M 5

H L - 6 0 N o n e 3 1 . 3 ( 6 1 . 2 ) 1 0 . 6 ( 2 6 . 2 ) 1 . 9 ( 7 . 0 )5 0 tM 1 . 3 ( 1 8 . 1 ) 3 5 . 7 ( 5 7 . 8 ) 1 1 . 7 ( 1 4 . 3 )

U 9 3 7 None 1 . 7 ( 1 4 . 6 ) 1 8 . 5 ( 3 2 . 1 ) 7 6 . 9 ( 9 1 . 9 )5 0 , u M 3 . 2 ( 2 1 . 3 ) 4 9 . 3 ( 5 4 . 0 ) 9 7 . 0 ( 1 8 9 . 6 )

H L - 6 0 a n d U 9 3 7 c e l l s w e r e s e e d e d a t 2 . 0 x 1 0 W c e l l s p e r m l a n d

g r o w n i n s e r u m - f r e e DME/F12 m e d i u m c o n t a i n i n g 5 0 , u M GM 3 f o r6 d a y s a n d t h e n w e r e a s s a y e d f o r a n t i g e n e x p r e s s i o n b y c y t o f l u o -r o m e t r y w i t h O r t h o S p e c t r u m I I I . C e l l s w e r e s t a i n e d f o r i n d i r e c ti m m u n o f l u o r e s c e n c e . V a l u e s i n p a r e n t h e s e s d e n o t e mean f l u o r e s -c e n t i n t e n s i t y a s m e a s u r e d b y c y t o f l u o r o g r a p h y o f p o s i t i v e c e l l s .V a l u e s r e p r e s e n t m e a n s o f d u p l i c a t e e x p e r i m e n t s , e a c h o f w h i c h

i n c l u d e d t r i p l e r e p l i c a t e s . S t a n d a r d d e v i a t i o n s w e r e < 1 0 % .

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7 8 6 M e d i c a l S c i e n c e s : N o j i r i e t a l .

1 2 3 4 5 6 7

T i m e i n c u l t u r e , d a y s

s u p p l e m e n t e d w i t h 10 % h e a t - i n a c t i v a t e d f e t a l c a l f s e r u m ) .F u r t h e r s t u d i e s on t h e m e c h a n i s m s o f d i f f e r e n t i a t i o n - i n d u c -t i o n w i t h GM 3 a n d on w h e t h e r t h e l a c t o - s e r i e s g a n g l i o s i d e s ,w h i c h h a v i n g l o n g e r s u g a r - m o i e t i e s a n d c h a r a c t e r i s t i c a l l yi n c r e a s e d u r i n g g r a n u l o c y t i c c e l l d i f f e r e n t i a t i o n o f H L - 6 0c e l l s , can i n d u c e g r a n u l o c y t i c c e l l d i f f e r e n t i a t i o n a r e n e e d e d .

W e t h a n k D r s . T . S u d a , M . O h t a , M. A k a s h i , Y . F u r u k a w a , a n dK . M o t o y o s h i ( D i v i s i o n o f H e mo p o i e s i s , I n s t i t u t e o f H e m a t o l o g y ,

J i c h i M e d i c a l S c h o o l ) f o r t h e i n v a l u a b l e a d v i c e d u r i n g t h i s w o r k . W ea l s o t h a n k M r . N . Y a h a g i ( O r t h o D i a g n o s t i c s ) f o r t h e c y t o f l u o r o -m e t r i c a n a l y s i s . T h i s w o r k w a s s u p p o r t e d i n p a r t b y G r a n t s - i n - A i df r o m t h e M i n i s t r y o f E d u c a ti o n , S c i e nc e a n d C u l t u r e , J a p a n .

1 0 - 6 l o - ,

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1 o - 4

F I G . 6 . E f f e c t o f v a r i o u s c o n c e n t r a t i o n s o f e x o g e n o u s l y a d d e dGM 3 o n c e l l g r o w t h a n d d i f f e r e n t i a t i o n o f H L - 6 0 c e l l s . ( L e f t )D o s e - d e p e n d e n t e f f e c t o f GM 3 o n c e l l g r o w t h o f H L - 6 0 c e l l s . H L - 6 0c e l l s w e r e s e e d e d a t a n i n i t i a l c o n c e n t r a t i o n o f 2 . 0 x 1 0 c e l l s p e r m la n d g r o w n i n t h e s e r u m - f r e e DME/F12 m e d i u m w i t h v a r i o u sc o n c e n t r a t i o n s o f GM3. C e l l s w e r e c o u n t e d i n a h e m o c y t o m e t e r , a n dv a r i o u s c o n c e n t r a t i o n s o f G M 3 . C e l l s w e r e c o u n t e d i n a h e m o c y -t o m e t e r , a n d v i a b i l i t y was c h e c k e d b y t h e e r y t h r o s i n e B d y e -e x c l u s i o n t e s t . E a c h d a t a p o i n t r e p r e s e n t s t h e mean o f t h r e e

d e t e r m i n a n t s . S t a n d a r d d e v i a t i o n sw e r e < 1 0 % o .

T h e v i a b i l i t y w a s>90% i n e a c h g r o u p t h r o u g h o u t t h e c u l t u r e p e r i o d s . o , W i t h o u tG M 3 ; e , w i t h 1 AM GM3; A, w i t h 1 0 AM GM3; A, w i t h 2 5 , u M GM3;n, w i t h 5 0 I i M GM3. ( R i g h t ) D o s e - d e p e n d e n t e f f e c t o f GM 3 o n c e l l

d i f f e r e n t i a t i o n o f H L - 6 0 c e l l s . C e l l s w e r e s e e d e d a t 2 . 0 x 1 0 5 c e l l s pe r

m l . D i f f e r e n t i a t i o n was d e t e r m i n e d b y N a p B t O E a s e s t a i n i n g a f t e r 6

d a y s o f g r o w t h w i t h t h e i n d i c a t e d c o n c e n tr a t i o n o f GM3. A s s e s s m e n to f N a p B t O E a s e - p o s i t i v e c e l l s was p e r f o r m e d f o r a minimum o f 2 0 0

c e l l s b y l i g h t m i c r o s c o p y . E a c h p o i n t r e p r e s e n t s t h e mean o f t h r e ed e t e r m i n a t i o n s , a n d v e r t i c a l b a r s s h o w s t a n d a r d d e v i a t i o n s .

r o l e a s t h e p r i m a r y t r i g g e r i n t h e d i f f e r e n t i a t i o n - i n d u c t i o n o fh u m a n m y e l o i d l e u k e m i c c e l l l i n e s a l o n g a m o n o c y t i c c e l ll i n e a g e . A c c u m u l a t i o n o f p a r t i c u l a r GSL m o l e c u l e s i n t h ep l a s m a m e m b r a n e a n d t h e r e s u l t i n g m e m b r a n e c o n s t i t u t i o n a lc h a n g e may t r i g g e r c e l l d i f f e r e n t i a t i o n .

I t h a s b e e n r e p o r t e d t h a t e x o g e n o u s l y a d d e d GSLs g r e a t l yr e d u c e d t h e g r o w t h o f t r a n s f o r me d c e l l s ( 1 3 , 1 5 , 3 1 ) . R e c e n t -

l y , B r e m e r e t a l . r e p o r t e d t h a t t h e s a m e g a n g l i o s i d e (GM1 or

GM3) t h a t i n h i b i t e d c e l l g r o w t h , i n h i b i t e d p l a t e l e t - d e r i v e dg r o w t h f a c t o r ( P D G F ) - d e p e n d e n t DNA s y n t h e s i s , a l t e r e dP DGF b i n d i n g , a n d r e d u c e d P D G F - s t i mu l a t e d p r o t e i n p h o s -p h o r y l a t i o n was a l s o t h e s a m e g a n g l i o s i d e t h a t w a s g r e a t l yr e d u c e d u p o n o n c o g e n i c t r a n s f o r ma t i o n o f S w i s s 3 T 3 c e l l s( 2 3 ) . T o g e t h e r w i t h t h e i r r e s u l t s , o u r p r e s e n t r e p o r t s u g g e s t s

t h a t a s t a t e o f d e c a r c i n o g e n e s i s m i g h t b e i n d u c e d i n t r a n s -

f o r m e d or t u m o r c e l l s o n t h e s u p p l y t o t h e p l a s m a m e m b r a n e s

o f a p a r t i c u l a r s p e c i e s o f G S L s , w h i c h i s g r e a t l y r e d u c e d i nt h e t u m o r c e l l s . As f o r t h e s p e c i f i c f u n c t i o n s o f g a n g l i o s i d e s ,T s u j i e t a l . ( 3 2 ) r e c e n t l y r e p o r t e d t h a t g a n g l i o s i d e GQ1bs p e c i f i c a l l y e x h i b i t e d n e r v e g r o w t h f a c t o r - l i k e a c t i v i t y . I ts h o u l d b e e m p h a s i z e d t h a t a p a r t i c u l a r g a n g l i o s i d e m o l e c u l a r

s p e c i e s , g a n g l i o s i d e GM3, w h i c h c h a r a c t e r i s t i c a l l y i n c r e a s e dd u r i n g m o n o c y t i c c e l l d i f f e r e n t i a t i o n o f h u m a n m y e l o i d a n d

m o n o c y t i c l e u k e m i c c e l l l i n e s , n o t o n l y s p e c i f i c a l l y s u p -

p r e s s e d c e l l g r o w t h b u t a l s o f u n c t i o n e d as a h i g h l y p o t e n t

i n d u c e r f o r t h e m o n o c y t i c c e l l d i f f e r e n t i a t i o n o f t h e s e c e l ll i n e s . I n p r e l i m i n a r y e x p e r i m e n t s , we h a v e o b s e r v e d t h a tf r e s h l e u k e m i c c e l l s o b t a i n e d f r o m p a t i e n t s w i t h a c u t e

p r o m y e l o c y t i c l e u k e m i a a l s o s h o w e d a t e n d e n c y t o d i f f e r e n -t i a t e a l o n g t h e m o n o c y t i c l i n e a g e when t r e a t e d w i t h 5 0 AMGM 3 i n a s e r u m - c o n t a i n i n g medium ( R P M I 1 6 4 0 medium

1 . K a r l s s o n , K . A . ( 1 9 7 6 ) i n S t r u c t u r e o f B i o l o g i c a l M e m b r a n e s( P l e n u m , N e w Y o r k ) , pp . 2 4 5 - 2 7 4 .

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( L o n d o n ) 2 7 0 , 3 4 7 - 3 4 9 .4 . C o l l i n s , S . J . , R u s c e t t i , F . W . , G a l l a g h e r , R . E . & G a l l o , R . C .

( 1 9 7 8 ) P r o c . N a t l . A c a d . S c i . USA 7 5 , 2 4 5 8 - 2 4 6 2 .

5 . B r e i t m a n , T . R . , S e l o n i c k , S . E . & C o l l i n s , S . J . ( 1 9 8 0 ) P r o c . N a t i .A c a d . S c i . USA 7 7 , 2 9 3 6 - 2 9 4 0 .

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5 1 5 2 - 5 1 5 8 .1 2 . S u n d s t r o m , C . & N i l s s o n , K . ( 1 9 7 6 ) I n t . J . C a n c e r 1 7 , 5 6 5 - 5 7 7 .

1 3 . L a i n e , R . A . & H a k o m o r i , S . - I . ( 1 9 7 3 ) B i o c h e m . B i o ph ys . R e s .

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R . E . ( 1 9 8 2 ) B i o c h e m . B i o ph y s . R e s . Commun. 1 0 5 , 2 2 5 - 2 3 0 .1 5 . K e e n a n , T . W . , S c h m i d , E . , F r a n k e , W. W. & W i e g a n d t , H . ( 1 9 7 5 )

E x p . C e l l R e s . 9 2 , 2 5 9 - 2 7 0 .

1 6 . C a l l i e s , R . , S c h w a r z m a n n , G . , R a d s a k , K . , S i e g e r t , R . &W i e g a n d t , H . ( 1 9 7 7 ) E u r . J . B i o c h e m . 8 0 , 4 2 5 - 4 3 2 .

1 7 . K a n d a , S . , I n o u e , K . , N o j i m a , S . , U t s u m i , H . & W i e g a n d t , H .( 1 9 8 2 ) J . B i o c h e m . ( T o k y o ) 9 1 , 1 7 0 7 - 1 7 1 8 .

1 8 . F i s h m a n , P . H . , M o s s , J . & V a u g h a n , M . ( 1 9 7 6 ) J . B i o l . C h e m . 2 5 1 ,4 4 9 0 - 4 4 9 4 .

1 9 . S c h w a r z m a n n , G . , H o f f m a n n - B l e i h a u e r , P . , S c h u b e r t , J . ,S a n d h o f f , K . & M a r s h , D . ( 1 9 8 3 ) B i o c h e m i s t r y 2 2 , 5 0 4 1 - 5 0 4 8 .

2 0 . M o m o i , T . , A n d o , S . & N a g a i , Y . ( 1 9 7 6 ) B i o c h i m . B i o p h y s . A c t a

4 4 1 , 4 8 8 - 4 9 7 .

2 1 . S u z u k i , K . ( 1 9 6 4 ) L i f e S c i . 3 , 1 2 2 7 - 1 2 3 3 .2 2 . B r e i t m a n , T . R . , C o l l i n s , S . J . & K e e n e , B . R . ( 1 9 8 0 ) E x p . C e l l

R e s . 1 2 6 , 4 9 4 - 4 9 8 .2 3 . B r e m e r , E . G . , H a k o m o r i , S . - I . , B o w e n - P o p e , D . F . , R a i n e s , E . &

R o s s , R . ( 1 9 8 4 ) J . B i o l . C h e m . 2 5 9 , 6 8 1 8 - 6 8 2 5 .2 4 . L i , C . Y . , L a m , K . W. & Y a m , L . T . ( 1 9 7 3 ) J . H i s t o c h e m .

C y t o c h e m . 2 1 , 1 - 1 2 .2 5 . K i t a g a w a , S . , O h t a , M . , N o j i r i , H . , K a k i n u m a , K . , S a i t o , M . ,

T a k a k u , F . & M i u r a , Y . ( 1 9 8 4 ) J . C l i n . I n v e s t . 7 3 , 1 0 6 2 - 1 0 7 1 .

2 6 . M i t t l e r , R . S . , T a l l e , M. A . , C a r p e n t e r , K . , R a o , P . E . & G o l d -

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1 5 2 , p p . 3 6 9 - 3 8 4 .

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3 1 . B r e m e r , E . G . & H a k o m o r i , S . - I . ( 1 9 8 2 ) B i o c h e m . B i o p h y s . R e s .

Commun. 1 0 6 , 7 1 1 - 7 1 8 .

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