Comparative profiling of HLA-DR and HLA-DQ associated factor VIII peptides presented by monocyte-derived dendritic cells.

5 years ago

Comparative profiling of HLA-DR and HLA-DQ associated factor VIII peptides presented by monocyte-derived dendritic cells.

Peyron, Hartholt, van Alphen, Voorberg, Ten Brinke, Meijer, Lardy, Pedró-Cos

The development of anti-factor VIII antibodies represents a major complication in the treatment of patients with hemophilia A. Generation of high affinity anti-factor VIII antibodies is dependent on help provided by CD4+ T cells that recognize factor VIII-derived peptides presented on class II major histocompatibility complex on the surface of antigen presenting cells. In order to identify the immune-dominant epitopes that can be presented to CD4+ T cells, we previously developed a mass-spectrometry based method to identify factor VIII derived peptides that are presented on human leucocyte antigen (HLA)-DR. In the present work, we compared the repertoire of FVIII-derived peptide presented on HLA-DR and HLA-DQ. Monocyte-derived dendritic cells from 9 HLA-typed healthy donors were pulsed with recombinant factor VIII. HLA-DR and HLA-DQ molecules were purified using monoclonal antibodies. Our data show that HLA-DQ and HLA-DR present a similar repertoire of factor VIII-derived peptides. However, the number of peptides associated with HLA-DQ was lower when compared to HLA-DR. We also identified a peptide, within the acidic a3 domains of factor VIII that is presented with higher frequency on HLA-DQ. Interestingly, this peptide was found to have a higher predicted affinity for HLA-DQ when compared to HLA-DR. Taken together, our data suggest that HLA-DQ participates in the presentation of factor VIII peptides, thereby contributing to the development of inhibitory antibodies in a proportion of patients with severe hemophilia A.

Publisher URL: http://doi.org/10.3324/haematol.2017.175083

DOI: 10.3324/haematol.2017.175083