Challenges to Cure: Transmission, Virulence and Pathogenesis of HIV Infection

Abstract

Human immunodeficiency virus (HIV) is a major contributor to the global burden of the disease, opportunistic infections, and tumors follow. HIV also directly attacks the immune system and affects certain body’s system (like Central Nervous System, Respiratory and Cardiovascular Systems, Digestive System etc). HIV transmission is complex and depends on the number of behavioral and biological co-factors. The hallmark of HIV infection is the progressive depletion of CD4 helper T cells because of reduced production and increased destruction. Although the typical HIV infected patient shows a sustained CD4 cell increase, a remarkable number of subjects never achieve normal ranges of CD4. HIV infection is also characterized by a marked increase in immune activation, which includes both the adaptive and innate immune systems and abnormalities in coagulation. Extraordinary efforts in the fields of clinical, pharmacology, and biology care have contributed to progressively turn HIV infection from an unavoidably fatal condition into a chronic manageable disease, at least in the countries where HIV infected people have full access to the potent anti-retroviral (ARV) drug combinations that permit a marked and sustained control of viral replication. Although their pathogenesis is still under-discussed, they are likely to originate from immune dysfunction associated with HIV infection and chronic inflammation. The last consideration regards the dis-homogenous pattern of HIV disease worldwide. Key-wordsHuman immunodeficiency virus (HIV), simian immunodeficiency viruses (SIV), Antiretroviral (ARV) therapy, Acquired immunodeficiency syndrome (AIDS), Cell mediated immunity (CMI), Anti-retroviral agents INTRODUCTION HIV virus is the harmful mediator of Acquired Immunodeficiency Syndrome (AIDS), was identified in 1983 following the first reported cases of AIDS in 1981-1982. HIV is a member of a class known as Retroviruses. These viruses store their genetic information as ribonucleic acid (RNA), unlike most viruses which store their genetic information as deoxyribonucleic acid (DNA). Previous to viral replication can obtain place, the RNA must be converted to DNA by the reverse transcription enzyme, hence the Latin term Retro, meaning 'turning back' . HIV comprises an outer envelope consisting of a lipid bilayer with spikes of glycoproteins (gp), gp41 and gp120 encoded by env gene. These glycoproteins (gp) are associated in such a manner that glycoproteins 120 protrude from the surface of the HIV virus. The envelope is inside membrane made of nucleocapsid (p 17, matrix protein), which surrounds a central core of protein, p24 (capsid protein) encoded by gag gene. Access this article online Quick Response Code Website: