6: HIV Replication & Pathogenisis Flashcards
- What is the main means of HIV transmission worldwide?
A. Unprotected heterosexual sex
B. Homosexual sex
C. Intravenous drug use
D. Mother-to-child transmission
A. Unprotected heterosexual sex
- HIV is a zoonotic infection that was first transmitted to humans by what animal?
A. Sand flies B. Gorillas C. Chimpanzees D. Mosquitos E. Fruit bats F. All of the above. G. None of the above.
C. Chimpanzees
- Choose the correct statement about male to female HIV transmission.
A. Vaginal epithelium is a poor barrier against the virus.
B. When HIV encounters macrophages and dendritic cells, productive infection events are frequent.
C. Vaginal tissue macrophages produce virions at the site of infection for weeks before the draining lymph nodes become infected.
D. A reservoir of latently infected T cells is established early during infection, once the virus reaches the draining lymph nodes.
E. All of the above.
F. None of the above.
A reservoir of latently infected T cells is established early during infection, once the virus reaches the draining lymph nodes.
- HIV is a retrovirus in the lentivirus group because:
A. It is slow to replicate in macrophages.
B. It is slow to replicate in T cells.
C. It is slow to cause disease in humans.
D. It is slow to cause disease in macaque monkeys.
E. It is slow to be eradicated from T cell reservoirs.
C. It is slow to cause disease in humans.
- Choose the correct statement about HIV structure:
A. Naked virion, icosahedral capsid, ssRNA genome
B. Naked, trapezoidal capsid, ssRNA genome
C. Enveloped, trapezoidal capsid, ssRNA genome
D. Enveloped, icosahedral capsid, ssRNA genome
C. Enveloped, trapezoidal capsid, ssRNA genome
- HIV uses the CD4 protein as a receptor for virus entry. What are the co-receptors for the virus?
A. Apoptosis death receptors B. Chemokine receptors C. Integrins D. G-protein coupled receptors E. Growth factor receptor tyrosine kinases
B. Chemokine receptors
HIV enters cells by what mechanism?
A. Fusion at the plasma membrane
B. Receptor mediated endocytosis
C. Fusion with an endosomal membrane
D. Uncoating at the nuclear pore
A. Fusion at the plasma membrane
- Following entry, what are the next steps in the HIV lifecycle (in the correct order).
A. Migration to the nucleus, circularization, conversion to DNA, integration into the chromosome
B. Integration into the chromosome, conversion to DNA, migration to the nucleus, circularization
C. Circularization, migration to the nucleus, conversion to DNA, integration into the chromosome
D. Conversion to DNA, circularization, migration to the nucleus, integration into the chromosome
D. Conversion to DNA, circularization, migration to the nucleus, integration into the chromosome
What enzyme is used to synthesize the dsDNA genome of HIV?
A. Reverse transcriptase B. Integrase C. DNA polymerase I D. RNA polymerase II E. DNA gyrase
A. Reverse transcriptase
- What enzyme is used to synthesize the genomic mRNAs that are packaged into the HIV virion?
A. Reverse transcriptase B. Integrase C. DNA polymerase I D. RNA polymerase II E. DNA gyrase
D. RNA polymerase II
- What event marks the end of Phase 1 of the HIV lifecycle?
A. Uncoating of the capsid in the cytoplasm
B. Conversion of the diploid mRNA genomes into DNA
C. Circularization of the DNA genome
D. Migration of the genome to the nucleus
E. Integration of the genome into the chromosome
F. Transcription of spliced and full-length mRNAs from the provirus
G. Translation of viral proteins from mRNAs
H. Assembly of the virion
E. Integration of the genome into the chromosome
- Choose the correct statement about syncytia formed by HIV-infected cells.
A. Syncytium formation is mediated by Env on the surface of infected T cells
B. Syncytia are multinucleated giant cells
C. T cells do not survive being incorporated into syncytia
D. Syncytia-inducing strains of HIV are more virulent than non-SI strains
E. The immunodeficiency of AIDS can be attributed, in part, to syncytia formation
F. All of the above
G. None of the above
- Choose the correct statement about syncytia formed by HIV-infected cells.
ANSWER = F. All of the above
A. Syncytium formation is mediated by Env on the surface of infected T cells
B. Syncytia are multinucleated giant cells
C. T cells do not survive being incorporated into syncytia
D. Syncytia-inducing strains of HIV are more virulent than non-SI strains
E. The immunodeficiency of AIDS can be attributed, in part, to syncytia formation
- Choose the correct statement about HIV pathogenesis.
A. High rates of virion production and T cell turnover create a dynamic equilibrium that allows virus mutants to emerge.
B. HIV first infects cells with CXCR4 (T cells), and later infects cells with CCR5 (macrophages)
C. Viral load and T cell counts are directly proportional
D. Other cells in the immune system are unaffected by HIV since they cannot be infected
E. The killing of T cells by HIV replication directly causes the death of the host
F. All of the above
G. None of the above
A. High rates of virion production and T cell turnover create a dynamic equilibrium that allows virus mutants to emerge.
_____ transmission and _____ (by illicit drug use) transmission are the most common routes of HIV transmission. Transmission from mother to fetus and from blood products does _____ occur in this country anymore!
Sexual transmission and bloodborne (by illicit drug use) transmission are the most common routes of HIV transmission. Transmission from mother to fetus and from blood products does NOT occur in this country anymore!
In the US nearly 2/3 of HIV transmission occurs to _____ and _____ men. In all other countries heterosexual transmission is the norm. African Americans are at higher riskfor HIV than whites or hispanics as well.
In the US nearly 2/3 of HIV transmission occurs to gay and bisexual men. In all other countries heterosexual transmission is the norm. African Americans are at higher riskfor HIV than whites or hispanics as well.
