Biomedical subjects

R L Coffman

Publications and source records attributed to R L Coffman.

172 records · Page 10Linked to original sources

PubMed1981

B220: a B cell-specific member of th T200 glycoprotein family.

T200, a major cell-surface glycoprotein on lymphoid cells, exists in several forms with different electrophoretic mobilities. These forms have been correlated with different classes of lymphoid cell. The smaller forms, with molecular weights (MWs) of congruent to 170,000 and 180,000 are found predominantly on T cells while the 220,000 MW form is associated with B cells. The polypeptide portions of each molecule may be identical or closely related as all three forms share the same allelic variations, and all reported herologous antisera and monoclonal antibodies to T200 precipitate all three forms. We report here a monoclonal antibody specific for the 220,000 MW form of T200 and show that it is expressed only on B cells and a subset of bone marrow cells which includes B cell precursors. We suggest that this form of the molecule be designated provisionally B220.

Animals↗

PubMed1981

A monoclonal antibody that recognizes B cells and B cell precursors in mice.

The monoclonal antibody, RA3-2C2, appears to be specific for cells within the B cell lineage. This antibody does not recognize thymocytes, peripheral T cells, or nonlymphoid hematopoietic cells in the spleen or bone marrow. Nor does it recognize the pluripotent hematopoietic stem cells, the spleen colony-forming unit, All sIg+ B cells and most plasma cells are RA3-2C2+. In addition, approximately 20% of nucleated bone marrow cells are RA3-2C2+ but sIg-. This population contains B cell precursors that can give rise to sIg+ cells within 2 d in vitro.

Animals↗

PubMed1979

The pathology and homing of a transplantable murine B cell leukemia (BCL1).

The pathology and homing characteristics of a murine B cell leukemia are described. Experiments utilizing autoradiography to determine the early homing pattern of the leukemic cells revealed a pronounced localization of the labeled cells to the spleen. The cells that were seen in the white pulp showed preferential localization to the follicles or B cell domains. Tissue section immunofluorescence with antibodies to kappa- and lambda-light chains was used to study the initial mouse with this disease as well as to study the mice that were injected with in vivo passaged cells. These mice also showed predominant involvement of the spleen. Although the initial mouse with this disease had 200,000 lambda-bearing B lymphocytes per mm3 in the peripheral blood and closely resembled a human chronic lymphocytic leukemia patient, the studies described suggest that this murine B cell neoplasm is a lymphoma with a striking predilection for splenic involvement. The other organs including the bone marrow as well as the peripheral blood appeared to be involved secondarily. This unusual spontaneously occurring murine B cell disease provides a useful model for the investigation of certain commonly occurring human lymphomas and leukemias.

Animals↗

PubMed1979

Surface Ig isotypes on cells responding to lipopolysaccharide by IgM and IgG secretion.

Using the fluorescence-activated cell sorter (FACS), we have investigated the Ig isotypes present on murine B cells, which can be polyclonally activated by lipopolysaccharide (LPS) in low cell density cultures. The LPS response was partly inhibited as a result of staining with anti-IgD and anti-IgM reagents, but not with anti-IgG reagents. The IgM+, IgD+, or IgG- fractionated cell populations gave both an IgM and an IgG response comparable to controls, whereas the response of the IgM-, IgD- cells was 5- to 20-fold lower. IgG- cells separated 1 day after LPS stimulation could still mount an IgM and IgG response indistinguishable from controls at the peak of the response. It is concluded that IgM+, IgD+, IgG- cells constitute the major LPS-sensitive cell population in the low cell density culture system and that IgG is not a necessary cell surface isotype for precursors of IgG-secreting cells.

Animals↗

PubMed1977

The class of surface immunoglobulin on virgin and memory B lymphocytes.

The class of surface immunoglobulin receptors for antigen on B cell precursors of different classes of antibody-forming cells was determined by utilizing a technique of class-specific antigen suicide. Spleen cells are first treated with a class-specific antiserum under conditions that result in the stripping of that class from the cell surface. The cells are then permitted to bind a highly radioactive trinitrophenyl (TNP)-conjugated protein, which leads to lethal irradiation of all TNP-specific B cells except those whose TNP receptors had been removed by the class-specific stripping of surface immunoglobulin. In this way, the class of antibody-forming cells resulting from TNP stimulation of B cells with different classes of surface immunoglobulin can be examined. It was found that the virgin B cell precursors of IgM-producing cells are two types: cells bearing IgM receptors only and those bearing both IgM and IgD receptors. All virgin B cells that gave rise to IgG1 antibody-forming cells had both IgM and IgD on their surfaces, demonstrating that an antigen-dependent switch from IgM and IgD to IgG1 production is a common feature of B cell maturation. In contrast, memory B cell precursors of IgG1 antibody-forming cells had predominantly IgG1 as their surface antigen receptor. The implications of these findings on current models of B cell maturation are analyzed.

Animals↗

PubMed1972