HIV virus primarily replicates in?
ANSWER: (A) CD4 helper T cellsREF: Jawetz microbiology 24th ed chapter 12"HIV infects vital cells in the human immune system such as helper T cells (specifically CD4+ T cells), macrophages, and dendritic cells"TROPISM:The term viral tropism refers to which cell types HIV infects. HIV can infect a variety of immune cells such as CD4+ T cells,macrophages, and microglial cellsMacrophage (M-tropic) strains of HIV-1 use the b-chemokine receptor CCR5 for entry and are, thus, able to replicate in macrophages and CD4+ T cells.T-tropic isolates replicate in primary CD4+ T cells as well as in macrophages and use the a-chemokine receptor, CXCR4, for entry.Dual-tropic HIV-1 strains are thought to be transitional strains of HIV-1 and thus are able to use both CCR5 and CXCR4 as co-receptors for viral entry.HIV strainTropismTargetChemokine CoreceptorR5 strainM-tropicMacrophagesCCR-5X4 strainT-tropicCD4 T cellsCXCR-4X4R5 strainDual tropicBoth macrophages & CD4 T cellsBoth CCR5 & CXCR-4 Steps in HIV replication cycle:Fusion of the HIV cell to host cell surfaceHIV RNA, reverse transcriptase, integrase and other viral proteins enters into the host cellViral DNA is formed by reverse transcriptionViral DNA is transported across the nucleus and integrates into the host DNANew viral RNA is used as genomic RNA and to make viral proteinsNew viral RNA and proteins move to cell surface and a new immature HIV virus forms.The virus matures by protease releasing individual HIV proteins
CD4 helper T cells
CD8 T cells
Natural killer cells
None
Human Immunodeficiency Virus