minor histocompatibility protein HMSD variant form; HSMD-v; contains: minor histocompatibility antigen ACC-6; mHA ACC-6 (HMSD)

Function

• allelic splice variant of HMSD
• precursor of histocompatibility antigen ACC-6
• ACC-6 is presented to the cell surface by MHC HLA-B*4403
• this complex specifically elicits donor-cytotoxic T lymphocyte (CTL) reactivity against hematologic malignancies after treatment by HLA-identical allogenic BMT.
• it induces cell recognition & lysis by CTL immunogenicity of most autosomal mHags results from single-nucleotide polymorphisms that cause amino-acid substitutions within epitopes, leading to the differential recognition of peptides between donor & recipient
• ACC-6 forms a complex with MHC HLA-B*4403

Alternative splicing

named isoforms=2

• alternative splicing is due 1 intronic SNP

Expression

• highly expressed in dendritic cells & primary leukemia cells, especially those of myeloid lineage.
• ACC-6 expression is limited to cells of hematopoietic lineage

Polymorphism

• minor histocompatibility antigen ACC-6 (mHA ACC-6) is encoded by HMSD-v which is an allelic variant of HMSD
• HMSD-v results from an intronic single-nucleotide polymorphism located at position 5 of HMSD intron 2 leading to a G to A substitution
• this variation in intron 2 induces skipping of exon 2 & frameshift, resulting in expression of ACC-6

Notes

• translation of HMSD-v form generating mHA ACC-6 is in a frame different from that resulting in HMSD non variant form expression
• thus, the HMSD non variant form sequence does not contain the mHA ACC-6 peptide

More general terms

• minor histocompatibility antigen

Additional terms

• Serpin-like protein HMSD; minor histocompatibility protein HMSD; minor histocompatibility serpin domain-containing protein (HMSD)

Database

• UniProt: http://www.uniprot.org/uniprot/P0C7T4.html