HIV/AIDS Flashcards
What are the five major groups of people at high risk for developing AIDS?
Homosexual or bisexual men, IV drug users, recipients of blood and blood components, heterosexual contacts of members of other high risk groups, HIV infection of the newborn
What are the three major routes of transmission of HIV? Which one is dominant?
Sexual contact, parenteral inoculation, passage of virus from infected mothers to their newborns
Sexual contact is dominant
What are the two ways viral transmission occurs?
Direct inoculation into blood vessels by trauma, infection of dendritic or CD4+ cells within mucosa
What are the three groups of individuals who have had parenteral transmission of HIV?
IV drug abusers, hemophiliacs who receive factor VIII and IX concentrates, random recipients of blood products
What is the most common form of HIV?
HIV-1
What type of virus is HIV/what family is it in?
Retrovirus - Lentivirus
What does the virus core of HIV contain?
- Major capsid protein p24
- nucleocapsid protein p7/p9
- two copies of viral genomic RNA
- three viral enzymes: reverse transcriptase, protease, integrase
What shape is the HIV virion? Does it have a lipid envelope?
Spherical - yes, lipid envelope is derived from host cell membrane
What are the three HIV-1 subgroups?
M (major), O (outlier), N (neither)
What is the most common subtype of group M HIV-1 in western Europe and the US? Which is the fastest spreading worldwide?
subtype B - most common
Fastest spreading: subtype/clade C
What are the two major targets of HIV infections?
Immune system and CNS
Where does virus remain latent for long periods in the body?
Lymphoid tissues
What protein on HIV binds to CD4 on cell surface?
gp120
What co-receptors does gp120 bind to?
CCR5 and CXCR4
HIV infects memory and activated T cells but is inefficient at productively infecting ______ T cells.
Naive or un-activated
What is the name of the active form of enzyme that naive T cells have that introduces mutations in the HIV genome? What type of mutations does it induce
APOBEC3G: cytosine to uracil mutations in viral DNA
What viral protein does HIV have that binds to APOBEC3g and promotes its degradation?
Vif
What type of cell is there a massive loss of with HIV infection?
CD4+ T cells
What type of cell undergoes a paradoxical activation leading to very large germinal centers with HIV infection?
B cells
What are the three phases of clinical presentation of HIV infection?
Acute retroviral syndrome, middle chronic phase, clinical AIDS
What generally causes death in patients with AIDS?
Opportunistic infections - often pneumonia from fungus Pneumocystic jiroveci
What is the most common fungal infection in patients with AIDS?
Candidiasis
What disease has there been a global resurgence of due to AIDS epidemic?
TB
Patients with AIDS have a high incidence of what types of cancers?
Kaposi’s sarcoma, B-cell lymphoma, cervical carcinoma (women), anal carcinoma (men)
What HIV protein promotes CD4 degradation to increase virion release?
vpu
What part of the HIV genome contains control regions that bind host TFs that are crucial for cytokine production?
LTR - long terminal repeats
