HIV-1 replication in dendritic cells occurs through a tetraspanin-containing compartment enriched in AP-3.
Dendritic cells (DC) are crucial components of the early events of HIV infection. Dendritic cells capture and internalize HIV at mucosal surfaces and efficiently transfer the virus to CD4+ T cells in trans through infectious synapses (trans-infection pathway). Alternatively, HIV-1 replicates in DC (R5-HIV-1) (cis-infection pathway). Here, we analyzed HIV trafficking in DC during the trans-infection pathway as well as the cis-infection pathway. Confocal immunofluorescence microscopy demonstrated that after capture by DC, R5-HIV-1 and HIV-1 pseudotyped with vesicular stomatitis virus protein G colocalized in a viral compartment enriched in tetraspanins including CD81, CD82 and CD9, although at different levels, indicating a role of the viral envelope in targeting to the tetraspanin-rich compartment. Replication of R5-HIV-1 in DC (cis-infection pathway) also led to the accumulation, in an envelope-independent manner, of mature viral particles in a tetraspanin-rich compartment. A fraction of the HIV-1-containing compartments appeared directly accessible from the cell surface. In sharp contrast with the trans-infection pathway, the delta-subunit of the adaptor protein 3 (AP-3) complex was enriched on the HIV-1-containing compartment during R5-HIV-1 replication in DC (cis-infection pathway). Downregulation of AP-3 delta-adaptin reduced significantly viral particle release from HIV-1-infected DC. Together, these studies demonstrate a role for AP-3 in HIV replication in a tetraspanin-rich compartment in DC and contribute to the elucidation of the trafficking pathways required for DC-T cell transfer of HIV-1 infection, a critical step during the early events of HIV infection.
Department of Dermatology and Venereology, University Hospital and Medical School of Geneva, 1211 Geneva, Switzerland.
Eduardo
E
Garcia
Damjan S
DS
Nikolic
Vincent
V
Piguet
D033963:Adaptor Protein Complex 3 / Q000502:physiology*; D033981:Adaptor Protein Complex delta Subunits / Q000502:physiology*; D015703:Antigens, CD / Q000032:analysis / Q000378:metabolism; D001692:Biological Transport / Q000502:physiology; D015496:CD4-Positive T-Lymphocytes / Q000821:virology; D002450:Cell Communication / Q000502:physiology; D018920:Coculture Techniques; D022162:Cytoplasmic Vesicles / Q000737:chemistry / Q000821:virology*; D003713:Dendritic Cells / Q000378:metabolism / Q000821:virology*; D015488:HIV Antigens / Q000032:analysis; D015497:HIV-1 / Q000502:physiology*; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D051861:Kangai-1 Protein / Q000032:analysis; D051907:Lysosomal Membrane Proteins / Q000032:analysis; D008562:Membrane Glycoproteins / Q000032:analysis; D008565:Membrane Proteins / Q000032:analysis* / Q000378:metabolism; D010980:Platelet Membrane Glycoproteins / Q000032:analysis; D034741:RNA, Small Interfering / Q000235:genetics; D060225:Tetraspanin 28; D060245:Tetraspanin 29; D060149:Tetraspanin 30; D014759:Viral Envelope Proteins / Q000502:physiology; D014771:Virion / Q000737:chemistry / Q000502:physiology; D014779:Virus Replication / Q000502:physiology*; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000032:analysis; D052118:Lysosomal-Associated Membrane Protein 1
D033963:Adaptor Protein Complex 3; D033981:Adaptor Protein Complex delta Subunits; D015703:Antigens, CD; D015488:HIV Antigens; D006684:HLA-DR Antigens; D051861:Kangai-1 Protein; D051907:Lysosomal Membrane Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010980:Platelet Membrane Glycoproteins; D034741:RNA, Small Interfering; D060225:Tetraspanin 28; D060245:Tetraspanin 29; D060149:Tetraspanin 30; D014759:Viral Envelope Proteins; D054301:gag Gene Products, Human Immunodeficiency Virus; C491904:AP3D1 protein, human; C554586:CD63 protein, human; C554798:CD81 protein, human; C497688:CD82 protein, human; C554869:CD9 protein, human; C489116:LAMP1 protein, human; D052118:Lysosomal-Associated Membrane Protein 1; C054858:p17 protein, Human Immunodeficiency Virus Type 1