gut microbiota diversity predicts immune status in hiv-1...

Piotr Nowak

Gut microbiota diversity predicts immune status in HIV-1

infection

Piotr Nowak MD, PhD. Karolinska Institutet, Stockholm

Hypothesis

The gut microbiota is changed in HIV infection which influences disease progression.

Antiretroviral therapy restores the composition of the gut microbiota.

Piotr Nowak

Study design – prospective observational

Patients (n=80) Inclusion criteria:

i) age >18 years ii) chronic HIV-1 infection iii) no antibiotics and probiotics <2 months iv) no diarrhea

Viremic untreated patients, n=28 n=19 followed longitudinally (median 10 months)

Elite controllers, n=3

HIV-negative controls, n=9

Piotr Nowak

HIV-1 infected subjects

Healthy Controls

Number of subjects 31 9

Age (years) 40.5 (19-67) 44.0 (28-62)

Male/female ratio 16/15 5/4

Ethnicity: Caucasian / African / Oriental

17/12/2 7/2/0

Mode of transmission: *MSM /IVDU /MSW

7/6/18

N/A

Years since diagnosis 3 (1-26) N/A

CD4 T cell count (cells/ul) 355 (120-2470) N/A

CD8 T cell count (cells/ul) 970 (380-2390) N/A

HIV-RNA (copies /ml) 48800 (<20**-990000) N/A

BMI 24 (18-36) N/A

** Three Elite controllers had undetectable HIV-1 RNA at baseline.

Patient characteristics

Piotr Nowak

Study design – prospective observational

Material and methods:

Blood and stool samples collected at baseline and at follow up.

16s rRNA from stool samples analysed by deep sequencing with Illumina platform (300 bp).

Plasma markers of microbial translocation /inflammation were analysed by ELISA or LAL assay.

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Results : number of observed taxa

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Results: alpha diversity

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Low diversity in HIV-1: low CD4-count

p=0.021

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Marker No of observed species Diversity (Shannon)

(r, p-value) (r, p-value)

CD4 T-cell count 0.59, p=0.009 0.40, p=0.02

CD4% 0.54, p=0.02 0.47, p=0.01

CD4/CD8 0.53, p=0.003 0.48, p=0.01

sCD14 -0.42, p=0.02 -0.41, p=0.02

LPS -0.51, p=0.007 -0.35, p=0.07

LBP -0.45, p=0.01 -0.32, p=0.09

sCD163 -0.48, p=0.02 -0.25, p=0.27

Diversity correlates with inflammation/microbial translocation

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Predictor Observed species

Covariates Beta-coefficient

(95% CI) p-value

Age, gender 0.88

(0.35-1.41) 0.002

Age, gender,

viral load

0.84

(0.28-1.40) 0.005

Age, gender,

BMI

1.02

(0.42-1.61) 0.002

Age, gender,

LPS

0.74

(0.23-1.26) 0.007

Age, gender,

sCD14

0.73

(0.17-1.28) 0.013

Piotr Nowak

No of bacterial species as independent predictors of CD4+ T cells in viremic patients (n=28)

Wei

ghte

d Un

ifrac

dive

rsity

inde

x

VP (n=2

8)

EC ( n=3

)

CTR (n=9

)0.2

0.3

0.4

0.5

0.6p<0.001

Interpatients (beta) diversity at baseline

Rela

tive

abun

danc

e(%

of to

tal b

acte

ria)

VP (n=28

)

EC (n=3)

CTR (n=9)

p__Actinobacteriap__Bacteroidetes

p__Firmicutesp__Proteobacteriap__Tenericutes

100%

50%

20%

Baseline composition of microbiota at phylum level in viremic patients, elite controlers and healthy controls

Five most abundant phyli are presented

Piotr Nowak

num

ber

of o

bser

ved

spec

ies

BL (n=16

)

FU (n=16

)0

100

200

300

400

500

p=0.001

Shan

non

dive

rsity

inde

x

BL (n=16

)

FU (n=16

)0

2

4

6

8p=0.006

a) b)

c)

Changes after ART: a) observed species b) intra- c) inter-patients diversity

Piotr Nowak

Conclusions

There are profound alterations both in diversity and composition of gut microbiota in HIV-1 infected patients.

Alpha diversity correlates positively with CD4 T cell counts inversely with sCD14, LPS, LBP and sCD163.

Short time ART does not restore gut microbiota.

Piotr Nowak

Acknowlodegments

Karolinska Institutet B. Barqasho U. Neogi A. Sönnerborg

Oslo University M. Troseid J. R. Hov E. Avershina K. Rudi

Piotr Nowak