Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Innate immune system wikipedia , lookup
Molecular mimicry wikipedia , lookup
Cancer immunotherapy wikipedia , lookup
Monoclonal antibody wikipedia , lookup
Polyclonal B cell response wikipedia , lookup
Immunosuppressive drug wikipedia , lookup
Diagnosis of HIV/AIDS wikipedia , lookup
HIV Part human, part HIV Lucy reading-Ikkanda for The Scientist, June 2011 Like other enveloped viruses, HIV exits its host cell enshrouded in the cell’s membrane, which contains membrane molecules such as the human leukocyte antigens (HLA). The HLA proteins act as a set of cell identification marks: every person expresses a slightly different HLA set. These molecules differentiate one person from another and allow the immune system to detect foreign invaders, and to reject tissue from other people or animals. Interestingly, each HIV particle has many more human HLA on its envelope surface than it has its own gp120 viral coat proteins, which the virus needs to bind to CD4 and CCR5 or CXCR4 on the lymphocyte surface in order to enter cells. Infected human CD4 T cell HIV particle HLA on surface of HIV particle HLA on surface of human cell Alloantigen based AIDS vaccine (ABAV) An HLA vaccine could consist of both inactivated HIV grown from lymphocytes expressing an array of HLA molecules 1 . The vaccine would be taken up by dendritic and other antigen-presenting cells 2, , which would trigger both an innate response, and adaptive responses such as the production of antibodies specific for the foreign HLA 3. During an infection, the antibodies would bind to the HIV particles’ HLA, marking it for elimination 4 . Antibodies to CCR5 would also be made, which help block viral entry 5 . If the virus bypassed these extracellular barriers, the innate response would create additional barriers and defenses: The b-chemokines MIP-1a, MIP-1b, and RANTES would block the HIV coreceptors CCR5 and CXCR4. Once inside the cell, intracellular factors EDN and APOBEC3G would damage the viral RNA, preventing it from properly replicating 6 . This one-two punch would, in theory, be enough to stop a viral infection. Diverse HLA Inactivated HIV particle 1 Dendritic cell 2 T cell Cytokines Plasma cells b chemokines (MIP-1a, MIP-1b and RANTES) Diverse HLA antibodies produced 3 CCR5 antibodies produced Viral RNA is damaged and HIV is neutralized 6 CCR5 receptor HIV is neutralized by antibodies 4 HIV cannot enter cell Human CD4 T cell is protected from HIV infection 5 CXCR4 receptor EDN and APOBEC3 are activated Self-HLA 06.2011 | The Scientist