Microbiology Chapter 31 HIV and other Retroviruses

Retroviruses replicate through a DNA intermediate, which requires an enzyme that can transcribe RNA into DNA.

What is it called

Reverse Transcriptase

gp 160 cleaves into gp_____ and gp_____

gp 120 (binds to CD4 helper T)

gp 41 (Transmembrane protein mediates fusion of virus with host cell)

HIV-1 can also infect cells that are CD4-negative, such as _______ and certain ______ cells

fibroblast, brain

Why is the HIV virus hard for immune system to recognize

Reverse Transcription is not accurate causing mutation in 1 of 2000 times leading to new strains

3 main gene clusters of HIV

gag

pol

env

gag: encodes (capsid p24, nucleocapsid p7, matrix p17)

pol: RT integrase and protease

env: gp41 and gp120

Accessory Proteins of HIV

Which are made from fully spliced mRNA?

Tat, Rev, Nef

(Vif, Vpu, Vpr) needs Rev for cytoplasmic transport

CD4 less than ______ is advanced HIV (AIDS)

200/uL

The main oral manifestations of HIV/ AIDS are _____ ____ and _____ _____ caused by Epstein-Barr virus

oral cadidiasis

hairy leukoplakia

Kaposi sarcoma is caused by what virus and is commonly associated seen in AIDS patient?

Human Herpesvirus (HHV8)

_________ lymphoma is commonly found in AIDS pt

Non-Hodgkin

What is the inital test for HIV and it has to be confirmed by ______ blot

ELISA (detect antibodies)

Western (HIV proteins)

What is the type of HIV virus through sexual contact

R5 virus

What is anergy?

Immune paralysis when CD4 T cells deactivated by abnormal HIV signals

HIV latency: What cell do the virus hide in and where

Memory CD4+ T cells in the lymph nodes

Also why it cannot be treated

When blood test is undetectable it large amounts of virus is still accumulating in the lymph nodes

Chronic immune activation and cytokine secretion damages lymph nodes causes tissue car disrupting _______ _______

cell communication

Role of CD8+ Cytotoxic T Lymphocytes (CTLs)

CTL kills infected cell producing HIV

Problem is that it requires CD4+ helpter T cells for activation

3 major routes of transmission of HIV

Sexual Transmission

Tramission Via Blood (needle)

Vertical Transmission

What drug reduces chance of vertical transmission of HIV

Give azidothymidine (zidovudine) to babies

What is HAART (Highly active antiretroviral therapy)

Multiple drug classes together

Prevent resistance and reduce viral to undetectable levels)

What is vorinostat

HDAC inhibitor

Activate latent HIV so immune system call kill

Still in trial

Oncovirinae

Lentivirinae

Spumavirinae

Human T cell lymphotropic virus

HIV1 and 2

First human retrovirus

HTLV-1

HTLV-2

Causes T-cell leukemia/lymphoma (treated with anticancer)

Causes hairy cell leukemia