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bioRxiv · 10.1101/2025.05.30.656890

HLA-DQ monomer-based enrichment of alloreactive CD4 T cells

Zhanzak, Z.·Cina, D.·Zhang, X.·Hadley, A.·Kissick, H.·Larsen, C.
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Abstract

Donor-specific T cell responses, particularly against human leukocyte antigen (HLA)-DQ antigens, are critical in transplant immunology as they influence graft survival and rejection. This study investigated HLA-DQ-specific CD4 T cell responses in naive individuals using HLA-DQ monomers, representing common donor HLA-DQ antigens (DQ2.5, DQ5, DQ6, DQ8), as defined alloantigen sources to enrich and detect HLA-DQ-specific T cells. Using a repeated stimulation protocol with HLA-DQ monomers, we achieved an enrichment of HLA-DQ-specific CD4 T cells, evidenced by proliferation and activation marker upregulation. Additionally, in silico epitope prediction identified 15-mer HLA-DQ peptides capable of binding to self-HLA-DRB1 alleles. TCR sequencing demonstrated an enriched, oligoclonal repertoire of HLA-DQ-specific CD4 T cells post-stimulation, with specific TCR clonotypes expanding in response to HLA-DQ monomer stimulation. Together, our study presents an in vitro method for enriching HLA-DQ-specific CD4 T cells using HLA-DQ monomers as an alloantigen source, thereby improving the detection of alloreactive, donor-specific T cells in naive individuals with the potential to mediate immune responses, including graft rejection and donor-specific antibody (DSA) production.

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Zhanzak, Z., Cina, D., Zhang, X., Hadley, A., Kissick, H., Larsen, C.. 2025-06-02. HLA-DQ monomer-based enrichment of alloreactive CD4 T cells. https://doi.org/10.1101/2025.05.30.656890

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