Search PubMed⌕ Search

Biomedical subjects

J F Kaufman

Publications and source records attributed to J F Kaufman.

23 records · Page 2Linked to original sources

Purification of HLA-linked B lymphocyte alloantigens in immunologically active form by preparative sodium dodecyl sulfate-gel electrophoresis and studies on their subunit association.

The HLA-linked B cell alloantigen (p29,34) is composed of two subunits of 29,000 (p29) and 34,000 (p34) molecular weight. The partially purified HLA-linked B cell alloantigen was purified by a final step of preparative sodium dodecyl sulfate-gel electrophoresis. An antiserum was prepared against p29,34 which specifically lysed B lymphocytes. In sodium dodecyl sulfate at 21 degrees, p29 and p34 remained noncovalently associated and retained immunologic activity; subunit dissociation at higher temperatures correlated with loss of immunologic activity. Although the pI values of p29 and p34 are 6.1 and 5.2, respectively, the subunits co-electrofocus under nondenaturing conditions. In addition, cross-linking studies showed the B cell antigen has a (p29)1(p34)1 subunit structure.

Antigen-Antibody Reactions↗

Purification and structural characterisation of human HLA-linked B-cell antigens.

The human B cell-specific alloantigen which is closely linked genetically to HLA contains two non-covalently associated, sialogycoprotein subunits of molecular weight (MW) 29,000 (p29), and 34,000 (p34). Although p29 and p34 have different amino-terminal sequences, their tyrosine peptide maps indicate considerable similarity in other portions of their polypeptide chains. Thus the genes for their proteins may have evolved by duplication of a common ancestral gene. Another lymphocyte cell surface protein of MW 16,000 (p16) has also been characterised. Both p16 and p44 (the heavy chain of HLA-A,B antigens) have been compared with p29 and p34.

Amino Acid Sequence↗

HLA-D associated alloantisera react with molecules similar to Ia antigens.

Two human alloantisera specific to bone marrow-derived lymphocytes (B cells) were shown to precipitate polypeptide chains of 29,000 and 34,000 daltons from human lymphoblastoid B cell lines. These molecules are similar to murine Ia antigens and are also precipitated by a rabbit B-cell specific heteroantiserum. Since the alloantisera are thought to recognize determinants coded by HLA-D or closely linked loci, these data support the hypothesis that these B-cell specific alloantigens are the human counterpart of the mouse Ia antigens and may be the products of HLA-D.

B-Lymphocytes↗