Pathogenesis of HIV infection, Clinical staging,Natural history of untreated HIV infection,
HIV structure HIV-1 and 2 are structurally similar (icosahedral) with the following components: Envelope : a lipid bilayer formed from host cell lipids and viral proteins. Embedded in the envelope is a complex protein env containing the viral surface glycoprotein, gp120 and a transmembrane glycoprotein, gp41. Both are derived from a precursor, gp160. Matrix : encapsulated by the envelope, made up of viral protein p17. Core : it comprises RNA dimer . Two identical copies of single-stranded RNA linked together, each containing ~9500 nucleotides. Associated with a nucleocapsid and its precursor protein. Capsid protein encapsulates the ribonucleoprotein core which contains three enzymes; reverse transcriptase, integrase, and protease. Genetic organization of HIV Genetic information is stored as RNA. Gene maps for HIV-1 and HIV-2 are similar except that HIV-2 has vpu instead of vpx . Both sides of the HIV provirus are flanked by a repeated sequence known as t...