Inhibition of proliferative and plaque-forming cell responses by human bone-marrow-derived lymphocytes from peripheral blood by antisera to the p23, 30 antigen.

Surface markers of complement receptor lymphocytes.

“…Among normal lymphoid cells, nearly all Ig-bearing cells and plasma-cell precursors express Ia, whereas Ta is undetectable on the vast majority of non-B and T lymphocytes (9,10,26). Furthermore, supporting evidence for Ia expression on Ig-negative pre-B cells has been provided by the demonstration of such characteristic pre-B cells in both normal marrow and marrow from patients with infantile hypogammaglobulinemia (27).…”

The Effect of Anti‐Ia Antibody on Immunoglobulin‐secreting Cells from Healthy Individuals and Myeloma Patients

“…The evidence that monoclonal anti-la antibody, instead of rabbit anti-la antibody, also reduced the number of ISC in the presence of rabbit complement further strengthens the conclusion that la-like antigen is present on the peripheral ISC of healthy individuals. Friedman et al [4] recently reported that PFC generated from peripheral mononuclear cells in the presence of PWM were reduced in number by treatment with anti-la antibody and complement, and Halper et al [6] reported that intracytoplasmic Ig-positive cells generated from tonsil lymphocytes in the presence of PWM had la-like antigen on their surface. These observations suggest that B cells at the stage of terminal differentiation still retain la-like antigen on the cell surface and possess the capacity to synthesize and secrete Ig.…”

“…Furthermore, these antigens are believed to be lost in the terminal differentiation of B lymphocytes and cannot be detected on fully differentiated plasma cells [3,6,13]. However, la-like antigens have been detected on plaque-forming cells (PFC) generated from peripheral lymphocytes [4] and intracytoplasmic immunoglobulin (Ig)positive cells generated from tonsil lymphocytes [6] by pokeweed mitogen (PWM) stimulation. Furthermore, I-A-and I-E/C-encoded molecules were detected on mouse splenocytes secreting IgM and IgG [14].…”

Suppression of Lymphoblastoid Cell Line Proliferation by Antisera to HLA‐DR and Other HLA Antigens

“…The antibodies produced are directed against those antigens which the fetus has inherited from its father. HLA antibodies are present as early as 61 weeks of pregnancy, possibly a reaction to antigens on trophoblastic membranes (Van der Wed 1971): Ia, p23.30 and alloreactivity also appear early in ontogeny of fetal liver cells and on pre-B-cells (Asantila et al 1974, Asantila & Toivanen 1976, Hammerling 1976, Friedman et al 1977. Although B-cell precurrnrs in the fetal liver do not acquire mature in vivo immunological function, such as immunoglobulin production, until around the time of birth, when transplated into immunodeficient hosts these cells are capable of reconstituting immune functions within several weeks in man (O'Reilly et al 1978).…”

“…p23.30 is expressed on peripheral B-cells, on a C3-positive null cell subset which produces immunoglobulin in witro and on fully differentiated antibody-forming cells. While antiserum to p23.30 completely inhibits the differentiation and function of antibody-forming cells, it has little or no effect when added late t o B-cell cultures: its action is on early proliferation and differentiation (Friedman et al 1977).…”