MHC-related protein 1-restricted recognition of cancer via a semi-invariant TCR-α chain.

The T cell antigen presentation platform MR1 consists of 6 allomorphs in humans that differ by no more than 5 amino acids. The principal function of this highly conserved molecule involves presenting microbial metabolites to the abundant mucosal-associated invariant T (MAIT) cell subset. Recent developments suggest that the role of MR1 extends to presenting antigens from cancer cells, a function dependent on the K43 residue in the MR1 antigen binding cleft.

Human β-defensin 2 ameliorates acute GVHD by limiting ileal neutrophil infiltration and restraining T cell receptor signaling.

Acute graft-versus-host disease (aGVHD), which is driven by allogeneic T cells, has a high mortality rate and limited treatment options. Human β-defensin 2 (hBD-2) is an endogenous epithelial cell-derived host-defense peptide. In addition to its antimicrobial effects, hBD-2 has immunomodulatory functions thought to be mediated by CCR2 and CCR6 in myeloid cells.