پاورپوینت AIDS and Lentiviruses (زبان انگلیسی)

دانلود پاورپوینت AIDS and Lentiviruses (زبان انگلیسی)

Introduction
Human immunodeficiency virus (HIV) derived from primate lentiviruses etiologic agents of AIDS
The illness was first described in 1981 and was isolated by the end of 1983
once infected, individuals remain infected for life
Within a decade, if left untreated, the vast majority of HIV-infected individuals develop fatal opportunistic infections as a result of HIV-induced deficiencies in the immune system.
AIDS the most important public health problems worldwide at the start of the 21st century.

Virion: Spherical & cylindric core

Genome: Single-stranded RNA, linear, positive-sense, diploid

Proteins: Envelope glycoprotein undergoes antigenic variation; reverse transcriptase enzyme contained inside virions; protease required for production of infectious virus

Envelope: Particles bud from plasma membrane

Replication: Reverse transcriptase makes DNA copy from genomic RNA; provirus DNA is template for viral RNA. Genetic variability is common.

Outstanding characteristics:

nononcogenic

may be cytocidal

Infect cells of the immune system

Cause slowly progressive, chronic diseases

4 genes required for a replicating retrovirus gag, pro, pol, and env
Up to 6 additional genes regulate viral expression and are important in disease pathogenesis in vivo.

Heterogeneous populations of viral genomes are found in an infected individual reflects high rates of viral replication and the high error rate of the viral reverse transcriptase.
The regions of greatest divergence env gene
The SU (gp120) binding domains virus attachment to the CD4 molecule and coreceptors determines lymphocyte and macrophage tropisms
The TM (gp41) transmembrane domain that anchors the glycoprotein in the viral envelope and a fusion domain that facilitates viral penetration into target cells.