Histocompatibility minor serpin domain containing protein (HMSD)

The **histocompatibility minor serpin domain containing protein** (HMSD) is a serpin-domain containing protein primarily expressed in cells of myeloid lineage and acting putatively as a serine protease inhibitor[1][2][5][7]. Polymorphisms in its gene can create immunogenic splice variants (notably the ACC-6 form) that serve as minor histocompatibility antigens (mHAs)[2][4][6]. These peptide antigens, when presented by MHC class I molecules (especially HLA-B*4403), are recognized by donor-derived cytotoxic T-lymphocytes after allogeneic stem cell transplantation, mediating effects such as graft-versus-leukemia (GVL) and graft-versus-host disease (GVHD)[2][4][6][8]. The ability to elicit a targeted immune response is being explored for immunotherapeutic purposes, particularly in selective targeting of hematologic malignancies[8]. Because HMSD-derived antigens can also induce alloreactive T-cell responses against healthy tissues, they are closely linked to both beneficial and adverse outcomes in transplantation and immune therapy[2][4][8].

Other names

ACC-6ACC6C18orf53HSMD-vMinor histocompatibility antigen ACC-6Minor histocompatibility protein HMSDSerpin-like protein HMSD

Target of T-cell mediated immunotherapy (graft-versus-leukemia effect through donor cytotoxic T-cell recognition of HMSD-derived peptides)