title: HIV-specific antibody-dependent phagocytosis matures during HIV infection.
abstract: Antibody-dependent phagocytosis (ADP) is a potentially important immune mechanism to clear HIV. How HIV-specific ADP responses mature during HIV infection or in response to vaccinations administered, including the partially successful RV144 HIV vaccine, is not known. We established a modified ADP assay to measure internalisation of HIV antibody (Ab)-opsonised targets using a specific hybridisation internalisation probe. Labelled beads were coated with both biotinylated HIV gp140 envelope protein and a fluorescent internalisation probe, opsonised with Abs and incubated with a monocytic cell line. The fluorescence derived from the fluorescent internalisation probe on surface-bound beads, but not from internalised beads, was quenched by the addition of a complementary quencher probe. HIV Env-specific ADP was measured in 31 subjects during primary infection and early chronic HIV infection. Although ADP responses were present early during HIV infection, a significant increase in ADP responses in all 31 subjects studied was detected (P<0.001). However, when we tested 30 HIV-negative human subjects immunised with the Canarypox/gp120 vaccine regimen (subjects from the RV144 trial) we did not detect HIV-specific ADP activity. In conclusion, a modified assay was developed to measure HIV-specific ADP. Enhanced ADP responses early in the course of HIV infection were observed but no ADP activity was detected following the vaccinations administered in the RV144 trial. Improved vaccine regimens may be needed to capitalise on ADP-mediated immunity against HIV.
authors.affiliation: Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Ana-Sosa-Batiz
authors.affiliation: 1] Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia [2] ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Australia.
authors.forename: Angus P R
authors.initials: AP
authors.lastname: Johnston
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia.
authors.forename: Haiyin
authors.initials: H
authors.lastname: Liu
authors.affiliation: Burnet Institute, Melbourne, Australia.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Center
authors.affiliation: Department of Disease Control, Ministry of Public Health, Bangkok, Thailand.
authors.forename: Supachai
authors.initials: S
authors.lastname: Rerks-Ngarm
authors.affiliation: Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Punnee
authors.initials: P
authors.lastname: Pitisuttithum
authors.affiliation: Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Sorachai
authors.initials: S
authors.lastname: Nitayaphan
authors.affiliation: Data Management Unit, Mahidol University, Bangkok, Thailand.
authors.forename: Jaranit
authors.initials: J
authors.lastname: Kaewkungwal
authors.affiliation: USA Military HIV Research Program, Walter Reed Army Institute of Research, Rockville, MD, USA.
authors.forename: Jerome H
authors.initials: JH
authors.lastname: Kim
authors.affiliation: USA Military HIV Research Program, Walter Reed Army Institute of Research, Rockville, MD, USA.
authors.forename: Nelson L
authors.initials: NL
authors.lastname: Michael
authors.affiliation: The Kirby Institute for Infection and Immunity in Society, UNSW Medicine, Sydney, Australia.
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Kelleher
authors.affiliation: Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia.
authors.forename: Ivan
authors.initials: I
authors.lastname: Stratov
authors.affiliation: 1] Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia [2] ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Melbourne, Melbourne, Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Kent
authors.affiliation: Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia.
authors.forename: Marit
authors.initials: M
authors.lastname: Kramski
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology; D000918:Antibody Specificity / Q000276:immunology; D000920:Antibody-Dependent Cell Cytotoxicity / Q000276:immunology; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D015483:HIV Antibodies / Q000097:blood / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D010587:Phagocytosis / Q000276:immunology*; D013997:Time Factors; D019562:Viral Load; D054299:env Gene Products, Human Immunodeficiency Virus / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D015483:HIV Antibodies; D007074:Immunoglobulin G; D054299:env Gene Products, Human Immunodeficiency Virus