Pathways utilized by dendritic cells for binding, uptake, processing and presentation of antigens derived from HIV-1.
The outcome following HIV infection depends on the nature and durability of the HIV-specific T cell response induced initially. The activation of protective T cell responses depends upon dendritic cells (DC), antigen-presenting cells which have the capacity to process and present viral antigens. DC pulsed with aldrithiol-2-inactivated HIV and delivered in vivo were reported to induce immune responses and promote virologic control in chronically HIV-1-infected subjects. To gain an understanding of this phenomenon, we characterized the steps involved in the presentation of antigens derived from aldrithiol-2-treated vs. infectious HIV-1 by DC. Antigen presentation, on both MHC class I and II, was independent of DC-specific ICAM-3-grabbing integrin, DEC-205 and macrophage mannose receptor, C-type lectins expressed by the DC. Inhibitor studies showed that presentation on MHC class I was dependent on viral fusion in a CD4/coreceptor-dependent manner, both at the cell surface and within endosomes, and access to the classical endosomal processing pathway. MHC class II presentation of HIV-associated antigens was dependent on active endocytosis, probably receptor-mediated, and subsequent degradation of virions in acidified endosomes in the DC. Our study brings forth new facts regarding the binding, uptake, and processing of chemically inactivated virions leading to efficient antigen presentation and should aid in the design of more effective HIV vaccines.
Sabado
Rachel L
RL
Department of Medicine and Pathology, School of Medicine, New York University, NY, USA.
Babcock
Ethan
E
Kavanagh
Daniel G
DG
Tjomsland
Veronica
V
Walker
Bruce D
BD
Lifson
Jeffrey D
JD
Bhardwaj
Nina
N
Larsson
Marie
M
D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives / Q000494:pharmacology; D017951:Antigen Presentation / Q000276:immunology*; D000998:Antiviral Agents / Q000494:pharmacology; D003713:Dendritic Cells / Q000276:immunology* / Q000821:virology*; D004220:Disulfides / Q000494:pharmacology; D015488:HIV Antigens / Q000276:immunology*; D015497:HIV-1 / Q000187:drug effects / Q000276:immunology*; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D006801:Humans; D014771:Virion / Q000187:drug effects / Q000276:immunology
D000998:Antiviral Agents; D004220:Disulfides; D015488:HIV Antigens; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; C001105:2,2'-dipyridyl disulfide; D015082:2,2'-Dipyridyl