Lm. Mendoza et al., MINORS HELD BY MAJORS - THE H13 MINOR HISTOCOMPATIBILITY LOCUS DEFINED AS A PEPTIDE MHC CLASS-I COMPLEX, Immunity, 7(4), 1997, pp. 461-472
The products of minor histocompatibility (H) loci are serious barriers
to tissue transplantation even among major histocompatibility complex
(MHC) identical individuals, frequently causing chronic graft rejecti
on and graft versus host disease. Over 50 minor H loci map to mouse au
tosomal chromosomes but none are known at the molecular level. By expr
ession cloning, we identified the H13 locus, a classical minor H locus
first detected 30 years ago by the trait of graft rejection. The H13(
a) allele is located on chromosome 2 and encodes a novel protein that
yields the rare naturally processed nonapeptide SSVVGVWYL (SVL9) for p
resentation by the D-b MHC class I molecule. The SVL9 peptide binds Db
MHC despite the absence of the consensus binding motif, and a conserv
ative methyl group substitution (Valine 4 <--> Isoleucine) explains wh
y reciprocal T cell responses are elicited in H13(a) and H13(b) congen
ic strains.