OBJECTIVE: Spondylarthritides (SpA), including ankylosing spondylitis (AS), are common inflammatory rheumatic diseases that are strongly associated with positivity for the HLA class I allotype B27. HLA-B27 normally forms complexes with β(2) -microglobulin (β(2) m) and peptide to form heterotrimers. However, an unusual characteristic of HLA-B27 is its ability to form β(2) m-free heavy chain homodimers (HLA-B27(2) ), which, unlike classic HLA-B27, bind to killer cell immunoglobulin-like receptor 3DL2 (KIR-3DL2). Binding of HLA-B27(2) to KIR-3DL2-positive CD4+ T and natural killer (NK) cells stimulates cell survival and modulates cytokine production. This study was undertaken to produce an antibody to HLA-B27(2) in order to confirm its expression in SpA and to inhibit its proinflammatory properties. METHODS: We generated monoclonal antibodies by screening a human phage display library positively against B27(2) and negatively against B27 heterotrimers. Specificity was tested by enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR) assay, and fluorescence-activated cell sorting (FACS) analysis of B27(2) -expressing cell lines and peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) from patients with SpA. Functional inhibition of KIR-3DL2-B27(2) interactions was tested using cell lines and PBMCs from patients with SpA. RESULTS: Monoclonal antibody HD6 specifically recognized recombinant HLA-B27(2) by ELISA and by SPR assay. HD6 bound to cell lines expressing B27(2) . FACS revealed binding of HD6 to PBMCs and SFMCs from patients with AS but not from controls. HD6 inhibited both the binding of HLA-B27(2) to KIR-3DL2 and the survival and proliferation of KIR-3DL2-positive NK cells. Finally, HD6 inhibited production of the proinflammatory disease-associated cytokine interleukin-17 by PBMCs from patients with AS. CONCLUSION: These results demonstrate that antibody HD6 has potential for use in both the investigation and the treatment of AS and other B27-associated spondylarthritides.
OBJECTIVE: Spondylarthritides (SpA), including ankylosing spondylitis (AS), are common inflammatory rheumatic diseases that are strongly associated with positivity for the HLA class I allotype B27. HLA-B27 normally forms complexes with β(2) -microglobulin (β(2) m) and peptide to form heterotrimers. However, an unusual characteristic of HLA-B27 is its ability to form β(2) m-free heavy chain homodimers (HLA-B27(2) ), which, unlike classic HLA-B27, bind to killer cell immunoglobulin-like receptor 3DL2 (KIR-3DL2). Binding of HLA-B27(2) to KIR-3DL2-positive CD4+ T and natural killer (NK) cells stimulates cell survival and modulates cytokine production. This study was undertaken to produce an antibody to HLA-B27(2) in order to confirm its expression in SpA and to inhibit its proinflammatory properties. METHODS: We generated monoclonal antibodies by screening a human phage display library positively against B27(2) and negatively against B27 heterotrimers. Specificity was tested by enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR) assay, and fluorescence-activated cell sorting (FACS) analysis of B27(2) -expressing cell lines and peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) from patients with SpA. Functional inhibition of KIR-3DL2-B27(2) interactions was tested using cell lines and PBMCs from patients with SpA. RESULTS: Monoclonal antibody HD6 specifically recognized recombinant HLA-B27(2) by ELISA and by SPR assay. HD6 bound to cell lines expressing B27(2) . FACS revealed binding of HD6 to PBMCs and SFMCs from patients with AS but not from controls. HD6 inhibited both the binding of HLA-B27(2) to KIR-3DL2 and the survival and proliferation of KIR-3DL2-positive NK cells. Finally, HD6 inhibited production of the proinflammatory disease-associated cytokine interleukin-17 by PBMCs from patients with AS. CONCLUSION: These results demonstrate that antibody HD6 has potential for use in both the investigation and the treatment of AS and other B27-associated spondylarthritides.
Authors: Lies Boelen; Bisrat Debebe; Marcos Silveira; Arafa Salam; Julia Makinde; Chrissy H Roberts; Eddie C Y Wang; John Frater; Jill Gilmour; Katie Twigger; Kristin Ladell; Kelly L Miners; Jyothi Jayaraman; James A Traherne; David A Price; Ying Qi; Maureen P Martin; Derek C Macallan; Chloe L Thio; Jacquie Astemborski; Gregory Kirk; Sharyne M Donfield; Susan Buchbinder; Salim I Khakoo; James J Goedert; John Trowsdale; Mary Carrington; Simon Kollnberger; Becca Asquith Journal: Sci Immunol Date: 2018-11-09