Binding Antibody Component | Duke Center for AIDS Research

Antigen specific antibody responses using customizable antigen-specific binding assays are provided by the CFAR Immunology core under GCLP-compliant conditions. These assays can be used to profile global changes in isotype and subclass responses to infection or vaccination. HIV, TB, and SIV specific assays are currently available. Antibody assays include a binding antibody multiplex assay (BAMA), Pharmacokinetic (PK) concentrations, avidity index assay (BAMA-AI) and antibody peptide microarray, virion capture and phagocytosis. The Binding Antibody Multiplex Assay (BAMA) has multiplex capability to profile antibody isotypes and subclasses (IgG1-4, dIgA, SCIgA, IgA1-2, IgM) for multiple antigens simultaneously (e.g. 50-100 different proteins/epitopes). We have developed standardized, qualified, and validated assays for multiple bNAbs in the product development pipeline, including parent and LS mAbs, in HIV-1 seronegative and seropositive serum (infants-adults). For the antigen specific assays, avidity measures can profile the strength of interactions using specific peptides and a sodium-citrate step. Peptide microarrays are available for HIV and SIV antigens (with potential for TB epitopes). HIV virion capture assays can distinguish the capacity of different antibody specificities to recognize infectious and noninfectious virus particles. HIV-1 phagocytosis assays are employed to test the ability of vaccine or infection induced antibodies to engage FcR on primary monocyte/macrophages and neutrophils in addition to recognition of virus particles.

Services Offered

Binding Antibody Multiplex Assay (BAMA)

Multiplex capability (µl sample volume, > 50 antigens /sample)
HIV-1, SIV, TB antigens
Subclass profiling (IgG, IgG1-4, IgA1-2, dIgA, SIgA, IgM, FcgammR)

Pharmacokinetics (PK)

PK concentrations in serum and mucosal specimens
Triplex method for simultaneous detection of multiple Abs

Avidity Index

Mucosal Samples (antigen specific and total Ig)

Peptide Microarray (HIV-1 and SIV)

HIV-1 cross-clade epitope mapping (Clades A, B, C,D, M; Thai and Clade C Vaccine strains)
SIV (mac239, smE660)
IgG, IgG3, IgA
Multiplex (>1900 peptides/sample; µl sample volume)
Plasma/Serum and Mucosal Samples

HIV-1 Virion Capture

Cross-clade Viruses
mAbs, Plasma, Mucosal (IgG, IgA)
Infectious vs. Noninfectious particle capture
Paired BAMA profiling

HIV-1 Antibody Mediated Phagocytosis

Antigen coupled beads, Infectious Virions
IgG, IgG3, IgA (mAbs, purified Ig from plasma/mucosa)
Primary monocyte/macrophages/ THP-1 Cells/ neutrophil like cell lines

Research Highlights

Antibody immune correlates for vaccine efficacy and preclinical translation. Effective implementation of an efficacious HIV-1 vaccine is an important goal put forth by the leaders of the National Institutes of Health to achieve an AIDS free generation. We have identified IgA, IgG, and IgG3 biomarkers of HIV-1 infection risk that along with evaluating antibody function can be instrumental in benchmarking HIV-1 clinical trials. In concert, many of the diverse antibody immune measurements measured as part of this CFAR Immunology Core can be utilized to benchmark both preclinical and clinical vaccine studies.

Moodie et al (2022). "Analysis of the HVTN 702 Phase 2b-3 HIV-1 vaccine trial in South Africa assessing RV144 antibody and T-cell correlates of HIV-1 acquisition risk." J Infect Dis. doi:10.1093/infdis/jiac260.
Wang, S., N. L. Yates, et al. (2022). "Broadly binding and functional antibodies and persisting memory B cells elicited by HIV vaccine PDPHV." NPJ Vaccines 7(1): 18. PMC8828892
Shangguan S, et al. (2021). Monocyte-derived transcriptome signature indicates antibody-dependent cellular phagocytosis as a potential mechanism of vaccine-induced protection against HIV-1. Elife. Sep 17;10:e69577. doi: 10.7554/eLife.69577. PMCID: PMC8514236
Neidich S et al. 2019 Antibody Fc Effector Functions and IgG3 Associate with Decreased HIV-1 Risk. Journal of Clinical Investigation 128(11):4838-4849. PMCID: PMC6819135

Pharmacokinetics (PK) for prevention and treatment. We have developed standardized, qualified, and validated assays for multiple bNAbs in the product development pipeline, including parent and LS mAbs, in HIV-1 seronegative and seropositive serum (infants-adults). Sample types include; serum, saliva, rectal, cervical, vaginal secretions and rectal, cervical, vaginal biopsies A rigorous data collection and QC process is employed to ensure data accuracy and integrity. We developed and published a multiplex assay for measurements of multiple antibodies and combinations simultaneously. Notably, we found that increased VRC01 concentration is associated with lower risk of HIV-1 acquisition.

Gilbert PB, et al.(2022) Nat Med. Neutralization titer biomarker for antibody-mediated prevention of HIV-1 acquisition. 2022 Sep;28(9):1924-1932.
Capparelli, EV; et al. (2022) JAIDS Safety and pharmacokinetics of intravenous 10-1074 and VRC01LS in young children.10.1097
Julg B et al. (2022) Nat Med Safety and antiviral activity of triple combination broadly neutralizing monoclonal antibody therapy against HIV 28:1288-1296:PMC9205771.
Wesley, et al. (2021) Front Immunol Validation of Tri-plex BAMA assay for simultaneous bNAb quantitation.

Binding antibody benchmarking for broadly neutralizing antibody induction. A major focus for vaccine development is the maturation of antibodies toward neutralization breadth. We have implemented methods to understand and track antibody maturation toward broadly neutralizing antibody activity in polyclonal serum and mucosal sites. Our studies including understanding how adjuvants modulate antibody quality; and what antibody antiviral functions are naturally present in PLWH that may be leveraged for effective vaccine design.

Xu S et al. (2022). Impact of adjuvants on the biophysical and functional characteristics of HIV vaccine-elicited antibodies in humans. NPJ Vaccines 7:90.
Nyanhete TE, et al. (2021) Polyclonal Broadly Neutralizing Antibody Activity Characterized by CD4 Binding Site and V3-Glycan Antibodies in a Subset of HIV-1 Virus Controllers. Frontiers in Immunology 2021 Dec 23;12:670561. doi: 10.3389/fimmu.2021.670561. PMCID: PMC8733328
Seaton, K. E. et al. (2021). "Meta-analysis of HIV-1 vaccine elicited mucosal antibodies in humans." NPJ Vaccines 6(1): PMC8405700
Williams LD, et al. (2017) Potent and broad HIV-neutralizing antibodies in memory B cells and plasma. Sci Immunol Jan 27;2(7). pii: eaal2200. doi: 10.1126/sciimmunol.aal2200. PMCID:PMC5905719