Molecular similarities between the Qa-2 alloantigen and other gene products of the 17th chromosome of the mouse.

Abstract

The alloantigen Qa-2, whose gene is located on the 17th chromosome between H-2D and Tla, is identified as a molecule of 43,000 daltons which is associated with beta 2-microglobulin. Qa-2 comprises approximately 0.15% of the iodinateable cell surface protein of lymph node cells. Sequential precipitations demonstrated that Qa-2 is distinct from H-2D and H-2K molecules.

Isolation of human tumour-specific antigens associated with β2 microglobulin

“…Similar results have been reported for the TL antigen (Artzt and Bennett, 1975;Michailson et al, 1977;Ostberg et al, 1975) which is closely linked to H-2D and apparently has a reciprocal interaction with it in the plasma membrane. In addition, in the region between H-2D and T/a, genes specify for a cell surface molecule Qa-2 which is similar to H-2D in molecular weight and association with /32m (Michailson et al, 1977). It is suggested that a family of molecules related by size, subunit structure, genetic linkage, membrane location and antigenicity may exist in this area of the chromosome, and may have arisen from a common ancestral gene (Michailson et al, 1977).…”

“…Recent biochemical evidence suggests that the antigenic products of both T/t and H-2 are structurally similar, and t12 has been reported to be associated with a /2m-like moiety in the membrane (Artzt and Bennett, 1975;Michailson et al, 1977). Similar results have been reported for the TL antigen (Artzt and Bennett, 1975;Michailson et al, 1977;Ostberg et al, 1975) which is closely linked to H-2D and apparently has a reciprocal interaction with it in the plasma membrane. In addition, in the region between H-2D and T/a, genes specify for a cell surface molecule Qa-2 which is similar to H-2D in molecular weight and association with /32m (Michailson et al, 1977).…”

“…In addition, in the region between H-2D and T/a, genes specify for a cell surface molecule Qa-2 which is similar to H-2D in molecular weight and association with /32m (Michailson et al, 1977). It is suggested that a family of molecules related by size, subunit structure, genetic linkage, membrane location and antigenicity may exist in this area of the chromosome, and may have arisen from a common ancestral gene (Michailson et al, 1977). Thus, in humans, similar non-HLA antigens may exist and structurally resemble antigens of the HLA complex; and these non-HLA antigens could possibly be involved in the expression of cell-surface TSAs.…”

Public antigenic determinant on a family of HLA-B molecules.

“…The demonistration that anti-X reacted with an HLA-like molecule containing f2A suggested that it might be reacting with HLA molecules themselves. However, in the mouse model, several other molecules (e.g., TL and Qa-3) besides H-2D and H-2K have been shown to have a structure similar to that of the major histocompatibility complex antigens (26,27). Therefore, to determine whether X was a determinant on the HLA-B molecules belonging to the B7 cross-reactive group, we performed a series of sequential immunoprecipitations.…”

Developmental and tissue-specific expression of the Q5 k gene

“…The Q region contains between one and ten loci (Weiss 1987). Class I gene products of this region are similar to the H-2K antigen in respect of nucleofide homology, antigenic crossreactivity, association with 32-microglobulin, and peptide structure (Michaelson et al 1977;Stanton and Hood 1980;Soloski et al 1981;Klein 1986). However, the Q genes differ from classical transplantation genes, which function as restriction elements for cytotoxic T lymphocytes, in several respects.…”