Surface-immunoglobulins

Knox KA, Gordon J (1994) Protein tyrosine kinases couple the surface immunoglobulin of germinal center B cells to phosphatidylinositol-dependent and -independent pathways of rescue from apoptosis. Cell Immunol 155 62-76... 

Cloning can also be performed using a FACS. Although a powerful technique, it is available to only a limited number of laboratories because of the cost of the equipment. Antigen coupled to a fluorescent marker is incubated with the cells. Cells with surface immunoglobulins of relevant specificity can then be isolated and sorted into individual tissue culture wells. 

Several effects of forskolin on B-lymphocytes, the cells of the immune system responsible for the production of immunoglobulins, have further been reported. This diterpene was found to inhibit cellular proliferation of B cells stimulated either by antibodies to surface immunoglobulins (anti-mu), and an antibody to CD20 antigen or 12-O-tetradecanoyl phorbol 13-acetate [219]. There was also a clear inhibition of G1 entry and DNA synthesis, and forskolin maintained its inhibitory effect even when added later after anti-mu stimulation. Additionally, no differences were found in the inhibitory effect of forskolin on neoplastic B cells, as compared to the responses of normal cells. Growth inhibition associated with an accumulation of cells in G1 was later found when cells of the B-lymphoid precursor cell line Reh were incubated with forskolin [220]. In that study, a delay of cells in G2/M prior to G1 arrest was observed, suggesting that important restriction points located in the G1 and G2 phases of the cell cycle may be controlled by forskolin (due to cAMP levels elevation). In a subsequent study [221], it was found that the arrest of Reh cells was accompanied by rapid dephosphorylation of retinoblastoma protein, which was suggested to be a prerequisite for the forskolin mediated arrest of these cells in Gl. 

Loor, F., Fomi, L., Pemis, B. (1972). The dynamic state of the lymphocyte membrane. Factors affecting the distribution and turnover of surface immunoglobulins. Eur. J. Immunol. 2,203-212. 

Melcher, U. Uhr, J.W. (1976). Cell surface immunoglobulin. XVI. Polypeptide chain structure of mouse IgM and IgD-like molecule. J. Immunol. 116,409-415. 

Taylor, R.B., Duffus, W.P.H., Raff, M.C., de Petris, S. (1971). Redistribution and pinocystosis of lymphocyte surface immunoglobulin molecules induced by anti-immunoglobulin antibody. Nature New Biol. 233, 225-229. 

Tyler, B.M., Cowman, A.F., Gerondakis, S.D., Adams, J.M., Bernard, O. (1982). mRNA for surface immunoglobulin y chains encodes a highly conserved transmembrane sequence and a 28-residue intracellular domain. Proc. Natl. Acad. Sci. USA 79,2008-2012. 

Yuan, D. Vitetta, E.S. (1978). Cell surface immunoglobulin. XXI. Appearance of IgD on murine lymphocytes during differentiation. J. Immunol. 120,353-356. 

Lam, K. P., R. Kuhn, and K. Rajewsky. 1997. In vivo ablation of surface immunoglobulin on mature B cells by inducible gene targeting results in rapid cell death. Ce//90 1073-1083. 

Foremost among these assays is the Raji cell assay developed by The-ofilopoulos and co-workers (T15). The Raji cell line, derived from a patient with Burkitt s lymphoma, lacks surface immunoglobulin, has Fc receptors that bind monomeric IgG only weakly, and possesses numerous receptors for Clq, C3b/C4b, C3d, and other complement components (G23, S4, S27, S28, T8, T12). Immune complexes which have fixed complement bind to... 

Surface immunoglobulin receptor of human B-cell lymphoma Tumor suppressor protein p53 mAb 5.5 against the ligand-binding site ot the nicotinic acetylcholine receptor Bovine pancreatic RNase fragment concanavalin A... 

The increase in phosphoinositide hydrolysis appears to occur during the G0 and early G[ phases of the cell cycle. Cells will not tolerate a sustained increase in intracellular Ca2+ and actively extrude the ion. Recent evidence in B lymphocytes, using calcium probes and image intensifies, shows that when surface immunoglobulin is crosslinked the rise of intracellular Ca2+ occurs in repeated short bursts [37]. 

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