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D W Lehman

Publications and source records attributed to D W Lehman.

5 recordsLinked to original sources
PubMed1983

Further studies on a hybrid cell-surface antigen associated with human chromosome 11 using a monoclonal antibody.

A monoclonal antibody has been obtained that recognizes an antigen encoded by human chromosome 11. We present evidence that this monoclonal antibody recognizes the same or a similar antigenic activity as that previously called a1. Genetic information necessary for a1 expression and recognition by the monoclonal antibody both map to 11p13 leads to 11pter. Mutants that have lost a1 are no longer recognized by the monoclonal antibody. The macroglycolipid fraction of human erythrocyte membranes which contains the a1 antigenic activity is able to convert antigen-negative Chinese hamster ovary cells into cells which are killed by the monoclonal antibody plus complement.

Animals↗
PubMed1980

Amino acid sequence of the variable region of a human mu chain: location of a possible JH segment.

The complete amino acid sequence of th variable (V) region of the mu heavy chain of a human IgM immunoglobulin (Cam) has been determined. The strategy for sequence determination involved sequenator analysis of the CNBr cleavage products of the succinylated carboxymethylated Fab mu fragment, and of tryptic peptides of the CNBr polypeptides and thermolytic subpeptides. The variable region of this heavy chain (VH) belongs to the VHIII subgroup; it has greater than 70% homology with other VHIII sequences and contains the VHIII marker peptide, Phe-Thr-Ile-Ser-Arg (residues 67-71). As more sequences have been published, the number of subgroup-specific residues has diminished to the point that no position is absolutely subgroup specific. An analysis of the available human VH sequences in the V/C switch region showed the likelihood of a human JH segment (residues 101-113) analogous to the J segments in mouse light chains. The JH region is highly conserved, has striking homology to proposed mouse JH regions, and has significant homology to known mouse J lambda and J kappa segments.

Amino Acid Sequence↗
PubMed1979

Genetic and biochemical analysis of the a1 cell-surface antigen associated with human chromosome 11.

A highly versatile system for genetic, biochemical, and immunological analysis of human cell surface components has been developed using a human-Chinese hamster somatic cell hybrid containing chromosome 11 as its only human chromosome. This system lends itself to studies such as identification of human cell surface antigens and other genetic markers, regional gene mapping of these markers on chromosome 11, mutational analysis of these markers, and exploration of distribution of these antigens in normal and pathological human tissues. Genetic analysis of a1, one of the human antigens expressed by this hybrid, has been accomplished by subjecting a series of a1- variants to complementation analysis. These experiments have shown that the a1- variants behave in a recessive manner and that at least four genes, including three Chinese hamster genes, are needed for a1 antigen expression. Biochemical analysis has shown that a macroglycolipid isolated from human erythrocytes contains the a1 antigenic activity, so that genes coding for glycosyltransferases are required for its biosynthesis and may correspond to the complementation groups identified. The power of combined genetic, biochemical, and immunological approaches to understanding cell membrane molecules is demonstrated.

Antigens, Surface↗