The B cell receptor (BCR) regulates B cell development and function through immunoglobulin (Ig)alpha and Ig beta, a pair of membrane-bound Ig superfamily proteins, each of which contains a single cytoplasmic immunoreceptor tyrosine activation motif (ITAM). To determine the function of Ig beta, we produced mice that carry a deletion of the cytoplasmic domain of Ig beta (Ig beta Delta C mice) and...

Recurrent non-random balanced chromosomal translocation, usually involving the immunoglobulin heavy chain (IgH) gene or an immunoglobulin light chain gene and a proto-oncogene, which results in the overexpression of the latter under the control of an enhancer or promoter of the former, is a hallmark of many types of non-Hodgkin lymphoma (NHL) of B-cell origin. However, translocations between Ig...

Because immunoglobulin (Ig)-b (CD79b) is required for immunoglobulin allelic exclusion, we examined the CD79b expressed by four chronic lymphocytic leukemia (CLL) samples that expressed more than one immunoglobulin heavychain allele and five samples that had normal immunoglobulin heavy-chain allelic exclusion. All leukemia cell samples stained poorly with monoclonal antibodies specific for extr...

The half disappearance time for detectable plasma membrane-associated and cytoplasmic immunoglobulin after treatment of continuously growing diploid lymphocytes with inhibitors of protein and RNA synthesis was studied. Also, the amount of plasma membrane-associated and cytoplasmic immunoglobulin of synchronized cells in the G(1) phase of the cell cycle has been studied. Plasma membrane-associat...

Because immunoglobulin (Ig)-beta (CD79b) is required for immunoglobulin allelic exclusion, we examined the CD79b expressed by four chronic lymphocytic leukemia (CLL) samples that expressed more than one immunoglobulin heavy-chain allele and five samples that had normal immunoglobulin heavy-chain allelic exclusion. All leukemia cell samples stained poorly with monoclonal antibodies specific for ...

Abstract The Lewis blood group system is unique because antigens are neither alleles of the same gene nor they synthesized by red cells (RBCs); rather, adsorbed onto RBC membrane from plasma as glycolipids. Antibodies against predominantly naturally occurring immunoglobulin (Ig)M type that sometimes react at 37°C and antihuman globulin phase. compound antigens, ALe b BLe , have been described w...

MRE11/RAD50/NBS1 (MRN) is a ubiquitous complex that participates in the response to DNA damage and in immunoglobulin (Ig) gene diversification. Ig gene diversification is initiated by deamination of cytosine to uracil, followed by removal of uracil to create an abasic (AP) site. We find that MRE11 associates specifically with rearranged Ig genes in hypermutating B cells, whereas APE1, the major...

One striking feature of spontaneous autoimmune diabetes is the prototypic formation of lymphoid follicular structures within the pancreas. Lymphotoxin (LT) has been shown to play an important role in the formation of lymphoid follicles in the spleen. To explore the potential role of LT-mediated microenvironment in the pathogenesis of insulin-dependent diabetes mellitus (IDDM), an LTbeta recepto...

Immunoglobulin class-switch recombination deficiencies (Ig-CSR-Ds) are rare primary immunodeficiencies characterized by defective switched isotype (IgG/IgA/IgE) production. Depending on the molecular defect in question, the Ig-CSR-D may be combined with an impairment in somatic hypermutation (SHM). Some of the mechanisms underlying Ig-CSR and SHM have been described by studying natural mutants ...

Cells from an established line of Burkitt's lymphoma (Daudi) and a mouse myeloma (P(3)K) were pulse-labeled in vitro with (3)H-leucine, and immunoglobulin was immunologically precipitated from cell lysates and secretions. In contrast to P(3)K cells, Daudi cells synthesize a small amount of Ig which is not secreted. Subcellular fractionation experiments indicated that Ig of Daudi cells is synthe...