human t lymphotropic viruses
TRANSCRIPT
Human T-Lymphotropic Viruses
oHuman T-Lymphotropic Virus Type 1
oHuman T-Lymphotropic Virus Type 2
A. Taxonomyo Family: Retroviridae
o Subfamily: Orthoretrovirinae
o Genus: Deltaretrovirus
o Species: Human T-Lymphotropic Virus 1
• Subtype:
a. Cosmopolitan Group
b. Central African Group
c. Melanesian Group
d. New Central African group
o Species: Human T-Lymphotropic Virus 2
B. Morphology & Composition
o Virion: spherical to pleomorphic, 80-110nm in
diameter
o Capsid: Icosahedral with helical nucleoprotein
o Composition: RNA(2%), Protein(about 60%),
Lipid(about 35%), Carbohydrate(3%)
o Genome: ssRNA, linear, positive-sense, 7-11kb
o Proteins: Reverse transcriptase- enzyme contained
inside the virions
o Envelope: Present
**Oncogenic
C. Replication, Morphogenesis, & Maturation
D. Pathogenesis
o Host:
o Humans (HTLV-1 and HTLV-2)
o Cell Tropism:
HTLV-1: CD4+ Tcells
HTLV-2: CD8+ Tcells
o Diseases:
o Asymptomatic Infection (Most common; HTLV-1 & 2)
o HTLV-1
o Adult T-cell leukemia-lymphomas (ATL) - Malignant
neoploasm of T lymphocytes
o Tropical Spastic Paraparesis - “HTLV-1 associated
myelopathy”
o HTLV-2
o Atypical Hair-cell leukemia
o Adult T-cell leukemia(ALT; RARE)
Mode of Transmission (HTLV-1 and HTLV-2)
Blood transfusion
Sharing of blood contaminated needles
(drug abusers)
Sexual intercourse
Mother-to-Child transmission
E. Treatmento No treatment exists for HTLV virus
o combination of interferon-alpha and
zidovudine had been reported to be effective
in treating ATL patients.
o combination of zidovudine, danazol, and
Vitamin C provides a temporary relief for TSP
patients.
F. Laboratory Diagnosiso Peripheral blood smear
o ATLL cells present
o Serology
o EIA
o Western Blot
o Detection of Proviral DNA
o PCR
i. Referenceo Medical Microbiology, 26th ed.: Jawetz, Melnick, and
Aldelberg
o Medical Virology, 4th ed,: White, and Fenner
o http://emedicine.medscape.com/article/219285-overview
o http://www.mayomedicallaboratories.com/test-catalog/Clin
ical+and+Interpretive/9539
o http://viralzone.expasy.org/
o https://www.youtube.com/watch?v=eS1GODinO8w
o http://www.arupconsult.com/Topics/HTLV.html
o http://virology-online.com/viruses/HTLV4.htm