Galectin-9 binding to HLA-DR in dendritic cells controls immune synapse formation and T cell proliferation.

ABSTRACT: To initiate T cell-mediated immunity, dendritic cells (DCs) present antigens to T cells through the establishment of an immune synapse (IS). While events behind IS formation in T cells are well understood, the organization of IS components at the DC membrane remains ill-defined. Galectins modulate immune responses via glycan-(in)dependent interactions but the molecular mechanisms underlying their function in DC-mediated T cell activation, are poorly described. Here, we demonstrate that intracellular galectin-9 (gal9) in DCs is required for CD4⁺ T cell activation through its interaction with the HLA-DR alpha- and beta- cytoplasmic domains, as supported by coimmunoprecipitation, mass spectrometry, and NMR analyses. Live-cell imaging revealed gal9-depleted DCs fail to establish sta

SUBMITTER: Rodgers-Furones A 

PROVIDER: S-EPMC12718305 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature