AIDS Research and Human RetrovirusesVol. 30, No. S1 B Cell Repertoires for ProtectionRole of Intestinal Microbiota in Shaping the B Cell Repertoire in HIV Infection and Env VaccinationLarry (Huaxin) Liao, A.M. Trama, W.B. Williams, M.A. Moody, Nathan Vandergrift, G.D. Tomaras, D.J. Marshall, T. Gurley, J. Whitesides, J. Eudailey, A. Foulger, R. Parks, C. Stolarchuk, K.E. Lloyd, K. Soderberg, J.R. Mascola, R. Koup, L. Corey, G.B. Nabel, P. Gilber, C. Morgan, J. Maenza, M. Keefer, S. Hammer, G. Churchyard, D.C. Montefior, B.S Graham, L.R. Baden, T.B. Kepler, and B.F. HaynesLarry (Huaxin) LiaoDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, A.M. TramaDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, W.B. WilliamsDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, M.A. MoodyDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, Nathan VandergriftDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, G.D. TomarasDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, D.J. MarshallDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, T. GurleyDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, J. WhitesidesDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, J. EudaileyDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, A. FoulgerDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, R. ParksDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, C. StolarchukDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, K.E. LloydDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, K. SoderbergDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, J.R. MascolaNational Institute of Allergy and Infectious Diseases, Vaccine Research Center, Bethesda, MD, United StatesSearch for more papers by this author, R. KoupNational Institute of Allergy and Infectious Diseases, Vaccine Research Center, Bethesda, MD, United StatesSearch for more papers by this author, L. CoreyUniversity of Washington, Fred Hutchinson Cancer Research Center, Seattle, WA, United StatesSearch for more papers by this author, G.B. NabelNational Institute of Allergy and Infectious Diseases, Vaccine Research Center, Bethesda, MD, United StatesSearch for more papers by this author, P. GilberUniversity of Washington, SCHARP, Fred Hutchinson Cancer Research Center, Seattle, WA, United StatesSearch for more papers by this author, C. MorganUniversity of Washington, Fred Hutchinson Cancer Research Center, Seattle, WA, United StatesSearch for more papers by this author, J. MaenzaUniversity of Washington, Fred Hutchinson Cancer Research Center, Seattle, WA, United StatesSearch for more papers by this author, M. KeeferUniversity of Rochester Medical Center, Division of Infectious Disease, Rochester, NY, United StatesSearch for more papers by this author, S. HammerColumbia University Medical Center, New York, NY, United StatesSearch for more papers by this author, G. ChurchyardThe Aurum Institute, Johannesburg, South AfricaSearch for more papers by this author, D.C. MontefiorDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this author, B.S GrahamNational Institute of Allergy and Infectious Diseases, Vaccine Research Center, Bethesda, MD, United StatesSearch for more papers by this author, L.R. BadenBrigham and Women's Hospital, Boston, MA, United StatesSearch for more papers by this author, T.B. KeplerBoston University, Boston, MA, United StatesSearch for more papers by this author, and B.F. HaynesDuke University Medical Center, Human Vaccine Institute, Durham, NC, United StatesSearch for more papers by this authorPublished Online:30 Oct 2014https://doi.org/10.1089/aid.2014.5023a.abstractAboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View article"Role of Intestinal Microbiota in Shaping the B Cell Repertoire in HIV Infection and Env Vaccination." AIDS Research and Human Retroviruses, 30(S1), p. A19FiguresReferencesRelatedDetails Volume 30Issue S1Oct 2014 InformationCopyright 2014, Mary Ann Liebert, Inc.To cite this article:Larry (Huaxin) Liao, A.M. Trama, W.B. Williams, M.A. Moody, Nathan Vandergrift, G.D. Tomaras, D.J. Marshall, T. Gurley, J. Whitesides, J. Eudailey, A. Foulger, R. Parks, C. Stolarchuk, K.E. Lloyd, K. Soderberg, J.R. Mascola, R. Koup, L. Corey, G.B. Nabel, P. Gilber, C. Morgan, J. Maenza, M. Keefer, S. Hammer, G. Churchyard, D.C. Montefior, B.S Graham, L.R. Baden, T.B. Kepler, and B.F. Haynes.Role of Intestinal Microbiota in Shaping the B Cell Repertoire in HIV Infection and Env Vaccination.AIDS Research and Human Retroviruses.Oct 2014.A19-A19.http://doi.org/10.1089/aid.2014.5023a.abstractPublished in Volume: 30 Issue S1: October 30, 2014PDF download

A successful HIV-1 vaccine must elicit immune responses that impede mucosal virus transmission, though functional roles of protective HIV-1 Envelope (Env)-specific mucosal antibodies remain unclear. Colostrum is a rich source of readily accessible mucosal B cells that may help define the mucosal antibody response contributing to prevention of postnatal HIV-1 transmission. To examine the HIV-1 Env-specific colostrum B-cell repertoire, single B cells were isolated from 17 chronically HIV-infected, lactating women, producing 51 blood and 39 colostrum HIV-1 Env-specific B-cell antibodies. All HIV-1 Env-specific colostrum-derived antibodies were immunoglobulin (Ig)G1 isotype and had mean heavy chain complementarity-determining region 3 (CDR3) lengths and mutation frequencies similar to those isolated from blood. However, variable heavy chain (VH) gene subfamily 1∼69 usage was higher among colostrum than blood HIV-1 Env-reactive antibodies (49% vs. 20%, P=0.006, Fisher's exact test). Additionally, more HIV-1 Env-specific colostrum antibodies were gp120 specific than those isolated from blood (44% vs. 16%, P=0.005, Fisher's exact test). One cross-compartment HIV-1 Env-specific clonal B-cell lineage was identified. These unique characteristics of colostrum B-cell antibodies suggest selective homing of HIV-1-specific IgG1-secreting memory B cells to the mammary gland and have implications for targeting mucosal B-cell populations by vaccination.

Background HIV-1 vaccines must induce protective antibodies at mucosal surfaces; the role of IgA in protection remains unknown. The HIV-1 Env antibody response begins ~day 17 after transmission, and derives from a polyreactive memory B cell pool of gut flora-reactive IgG1 and IgA B cells. Whereas the IgG Env antibody response persists years after acute HIV-1 infection, the initial IgA response decreases over the first month. There is also selective destruction of terminal ileum germinal centers in early HIV-1 infection (EHI). To determine HIV-1 IgA responses in gut, we isolated Env-reactive antibodies from ileum from patients in EHI and chronic HIV-1 infection (CHI).

Background Antibody Dependent Cellular Cytotoxicity (ADCC) may be a contributing factor of immune responses controlling HIV-1 replication. Understanding the epitopes recognized by ADCC-mediating antibodies is likely to be important for the development of an effective AIDS vaccine. We characterized the epitope specificity and breadth of the ADCC-mediating antibody response elicited by the RV144 vaccine regimen.

The ALVAC-HIV/AIDSVAX-B/E RV144 vaccine trial showed an estimated efficacy of 31%. RV144 secondary immune correlate analysis demonstrated that the combination of low plasma anti-HIV-1 Env IgA antibodies and high levels of antibody-dependent cellular cytotoxicity (ADCC) inversely correlate with infection risk. One hypothesis is that the observed protection in RV144 is partially due to ADCC-mediating antibodies. We found that the majority (73 to 90%) of a representative group of vaccinees displayed plasma ADCC activity, usually (96.2%) blocked by competition with the C1 region-specific A32 Fab fragment. Using memory B-cell cultures and antigen-specific B-cell sorting, we isolated 23 ADCC-mediating nonclonally related antibodies from 6 vaccine recipients. These antibodies targeted A32-blockable conformational epitopes (n = 19), a non-A32-blockable conformational epitope (n = 1), and the gp120 Env variable loops (n = 3). Fourteen antibodies mediated cross-clade target cell killing. ADCC-mediating antibodies displayed modest levels of V-heavy (VH) chain somatic mutation (0.5 to 1.5%) and also displayed a disproportionate usage of VH1 family genes (74%), a phenomenon recently described for CD4-binding site broadly neutralizing antibodies (bNAbs). Maximal ADCC activity of VH1 antibodies correlated with mutation frequency. The poly-clonality and low mutation frequency of these VH1 antibodies reveal fundamental differences in the regulation and maturation of these ADCC-mediating responses compared to VH1 bNAbs.

Methods Blood PCs from three AHI subjects obtained approximately 17, 20 and 30 days after HIV-1 transmission were sorted into 96-well plates for amplification of VH and VL genes by RT/PCR. The isolated VH and VL genes were expressed as recombinant IgG1 mAbs in 293T cells by transfection using linear Ig expression cassettes, The specificity of produced mAbs was determined by ELISA and luminex bead immunoassays against a panel of HIV-1 and non-HIV-1 antigens.