An analysis was made of the immunoglobulin surface markers of the cells of patients with chronic lymphatic leukemia (CLL) in view of previous evidence of their monoclonal B-cell character. The simultaneous presence of IgM and IgD on the surface of the majority of lymphocytes was demonstrated by both immunofluorescence and hemagglutination inhibition in most cases. However, cases were observed w...

Immunoglobulin (Ig)M+IgD+ B cells are generally assumed to represent antigen-inexperienced, naive B cells expressing variable (V) region genes without somatic mutations. We report here that human IgM+IgD+ peripheral blood (PB) B cells expressing the CD27 cell surface antigen carry mutated V genes, in contrast to CD27-negative IgM+IgD+ B cells. IgM+IgD+CD27(+) B cells resemble class-switched and...

For decades, it has remained unknown whether artiodactyls, such as cattle, pigs, and sheep, express immunoglobulin D (IgD), although the δ gene was identified in these species nearly 10 years ago. By developing a mouse anti-bovine IgD heavy chain monoclonal antibody (13C2), we show that secreted bovine IgD was present mainly as a monomer in serum and was heavily glycosylated by N-linked sacchar...

Immunoglobulin (Ig)M 1 IgD 1 B cells are generally assumed to represent antigen-inexperienced, naive B cells expressing variable (V) region genes without somatic mutations. We report here that human IgM 1 IgD 1 peripheral blood (PB) B cells expressing the CD27 cell surface antigen carry mutated V genes, in contrast to CD27-negative IgM 1 IgD 1 B cells. IgM 1 IgD 1 CD27 1 B cells resemble class-...

A series of immunoglobulin (Ig)-transgenic mice were generated to study the functional capabilities of the IgM and IgD classes of B lymphocyte antigen receptor in regulating both cellular development and responses to specific antigen. B cells from Ig-transgenic mice expressing either hen-egg lysozyme (HEL)-specific IgM or IgD alone were compared with B cells from mice that coexpressed IgM and I...

The review by Drs. Pandey and Kyle[1] highlights important facets of the management and diagnosis of rare subtypes of myeloma. Immunoglobulin D multiple myeloma (IgD MM) affects less than 2% of all patients with myeloma, and only about 50 cases of immunoglobulin E (IgE) MM have been described in the literature.[2,3] Based upon the rarity of these subtypes, few series of either subtype are repor...

To assess the role of immunoglobulin D (IgD) in vivo we generated IgD-deficient mice by gene targeting and studied B cell development and function in the absence of IgD expression. In the mutant animals, conventional and CD5-positive (B1) B cells are present in normal numbers, and the expression of the surface markers CD22 and CD23 in the compartment of conventional B cells indicates acquisitio...

Receptors for immunoglobulins on animal cells invariably show specificity for Fc regions of the protein and are hence called Fc receptors. The present study shows that immunoglobulin D receptors present an exception to this rule. Binding of IgD-coated erythrocytes to murine IgD-receptor-bearing T-helper cells is competitively inhibited by IgD, by its Fab delta fragments, and by deletion mutants...

The zebrafish is an emerging model for comparative immunology and biomedical research. In contrast to the five heavy chain isotype system of mice and human (IgD, IgM, IgA, IgG, IgE), zebrafish harbor gene segments for IgD, IgM, and novel heavy chain isotype called IgZ/T which appears restricted to bony fishes. The purpose of this study was to design and validate a suite of quantitative real tim...

Previous studies on a limited number of birds suggested that the IgD-encoding gene was absent in birds. However, one of our recent studies showed that the gene was definitely expressed in the ostrich and emu. Interestingly, we also identified subclass diversification of IgM and IgY in these two birds. To better understand immunoglobulin genes in birds, in this study, we analyzed the immunoglobu...