chapter 19- HIV (human immunodeficiency virus)

HIV selectively infects…. cells

T-helper

what is the genus of HIV

*Lentivirus*

what type of virus is HIV

retrovirus

what is contained with the capsid of HIV

2 identical strands of RNA

what are two important enzymes that HIV contain

reverse transcriptase

integrase

cell plasma membrane of HIV is … (phospholipid)

enveloped

what are found on the other surface of HIV

spike proteins

what are two specific regions of the spike proteins

gp120

gp41

gp120 combine with … receptors

CD4+

what three types of cells are CD4 molecules are carried on

T helper cells

macrophages

dendritic cells

basic three stages of HIV attachment to receptors on target T cell

1. attachment
2. fusion
3. entry

explain the attachment stage of HIV attachment to receptors on target T cell

the gp120 spike attaches to a receptor and to a CCR5 or CXCR4 receptor on the cell

explain the fusion stage of HIV attachment to receptors on target T cell

the gp41 participates in fusion of the HIV with the cell

explain the entry stage of HIV attachment to receptors on target T cell

entry pore is created

after entry, the viral envelope remains behind and the HIV un-coats, releasing the RNA core for directing synthesis of new viruses

what is used to convert single-stranded RNA to DNA

reverse transcriptase

Viral DNA integrates into the … chromosome as a …

host

provirus

SHORT ANSWER QUESTION… stages of multiplication of HIV

1. enters by fusion between attachment spikes and the host cell receptors
2. un-coating releases the RNA strands and enzymes
3. reverse transcriptase copies viral RNA to produce double-stranded DNA
4. the new viral DNA goes into the host cell’s nucleus and is integrated into the host cell chromosome, using integrase
5. virus matures and eventually leaves the host cell after acquiring everything it needs such as an envelope and attachment spikes

an active infection is when new viruses bud from …

host cells

a latent infection is when DNA is … in the chromosome as a …

hidden

provirus

HIV normally attacks … first and the goes onto the … … and then finally reaches the … cells

macrophages

lymph nodes

T-helper cells

what are the two subtypes of HIV

HIV-1

HIV-2

what type of HIV is more prevalent

HIV-1

HIV-1 is related to viruses that infect … and …

chimpanzees and gorillas

HIV-2 is not often encountered outside of…

West Africa

which of the two subtypes are less pathogenic

HIV-2

which of the two subtypes has a longer asymptomatic period and a lower viral load and morality rate

HIV-2

what is the main character of phase 1 of HIV infection

asymptomatic

in phase 2 of HIV infection, what steadily declines

CD4+ T cells

in phase 2 of HIV infection only a few … cells release the virus and there are few serious … ….

infected

disease symptoms

what develops in phase 3 of HIV infection

AIDS develop

in phase 3 of infection the CD4+ count is below … cell/ ul

200

AIDS is defined as

late stage of HIV infection that occurs when the body’s immune system is badly damaged because of the effect of the virus

HIV infections usually have a … and … initial immune response

strong and effective

… suppress viral numbers

CLTs

why is it impossible to clear the HIV infection

HIV establishes a pool of latently infected CD4+ T cells

what two age groups are more susceptible to HIV infection and lowers their chances of survival due to an underdeveloped immune system

young children

older adults

what mutation allows individuals to be exposed to HIV virus but never infected from it

CCR5

long term survivors will usually have a… (2 things)

low viral load

effective CLTs

HIV can survive up to … hours outside a cell

6

HIV can survive more than … days inside a cell

1\.5

what form of sexual contact is the most dangerous in terms of HIV infection

anal-receptive intercourse

there are more than .. million people infected with AIDS worldwide

36

around … % of infected people with AIDS are found in Africa

70

1/3 of AIDs cases in Eastern Europe and Central/ Southeast Asia are from the use of…

infected needles

… transmission is the most common mode of HIV transmission

heterosexual

when gender has a higher rate of HIV transmission

males

what are three types of interventions which are being used to prevent/ treat AIDs

biomedical

behavioral

structural

what would happen if a drug was administered for HIV that inhibited fusion/ entry

gp120 receptor will not be able to attach to the CD4+ receptor on the T-helper cell

what would happen if a drug was administered for HIV that inhibited reverse transcriptase

HIV would be not be able to replicate the single stranded RNA stranded into DNA

what would happen if a drug was administered for HIV that inhibited integrase

the new viral DNA will not be able to integrate into the host cell chromosome

what would happen if a drug was administered for HIV that inhibited protease

convert viral precursor proteins into structural and functional proteins