title: Opsonization of HIV with complement enhances infection of dendritic cells and viral transfer to CD4 T cells in a CR3 and DC-SIGN-dependent manner.
abstract: In the present study, we demonstrated that opsonization of primary HIV-1 with human complement enhances infection of immature monocyte-derived dendritic cells (iDC) and transmission in trans of HIV to autologous CD4(+) T lymphocytes. Infection of iDC by opsonized primary R5- and X4-tropic HIV was increased 3- to 5-fold as compared with infection by the corresponding unopsonized HIV. Enhancement of infection was dependent on CR3 as demonstrated by inhibition induced by blocking Abs. The interaction of HIV with CCR5 and CXCR4 on iDC was affected by opsonization. Indeed, stromal-derived factor-1 was more efficient in inhibiting infection of iDC with opsonized R5-tropic HIV-1(BaL) (45%) than with heat-inactivated complement opsonized virus and similarly RANTES inhibited more efficiently infection of iDC with opsonized X4-tropic HIV-1(NDK) (42%) than with heat-inactivated complement opsonized virus. We also showed that attachment of complement-opsonized virus to DC-specific ICAM-grabbing nonintegrin (DC-SIGN) molecule on iDC and HeLa DC-SIGN(+) CR3(-) cells was 46% and 50% higher compared with heat-inactivated complement opsonized virus, respectively. Hence, Abs to DC-SIGN suppressed up to 80% and 60% the binding of opsonized virus to HeLa cells and iDC, respectively. Furthermore, Abs to DC-SIGN inhibited up to 70% of the infection of iDC and up to 65% of infection in trans of autologous lymphocytes with opsonized virus. These results further demonstrated the role of DC-SIGN in complement opsonized virus uptake and infection. Thus, the virus uses complement to its advantage to facilitate early steps leading to infection following mucosal transmission of HIV.
authors.affiliation: Université René Descartes Paris V and Institut National de la Santé et de la Recherche Médicale, Unité 743, Institut des Cordeliers, Paris, France. hicham.bouhlal@u430.bhdc.jussieu.fr
authors.forename: Hicham
authors.initials: H
authors.lastname: Bouhlal
authors.forename: Nicolas
authors.initials: N
authors.lastname: Chomont
authors.forename: Mary
authors.initials: M
authors.lastname: Réquena
authors.forename: Nadine
authors.initials: N
authors.lastname: Nasreddine
authors.forename: Héla
authors.initials: H
authors.lastname: Saidi
authors.forename: Jérôme
authors.initials: J
authors.lastname: Legoff
authors.forename: Michel D
authors.initials: MD
authors.lastname: Kazatchkine
authors.forename: Laurent
authors.initials: L
authors.lastname: Bélec
authors.forename: Hakim
authors.initials: H
authors.lastname: Hocini
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002454:Cell Differentiation; D002472:Cell Transformation, Viral / Q000502:physiology*; D002478:Cells, Cultured; D003165:Complement System Proteins / Q000378:metabolism*; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism*; D006678:HIV / Q000502:physiology*; D006801:Humans; D037181:Lectins, C-Type / Q000378:metabolism*; D016177:Macrophage-1 Antigen / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology / Q000378:metabolism; D010641:Phenotype; D019713:Receptors, CCR5 / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015815:Cell Adhesion Molecules; D003165:Complement System Proteins; D037181:Lectins, C-Type; D016177:Macrophage-1 Antigen; D019713:Receptors, CCR5; D019718:Receptors, CXCR4; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin