{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,1]],"date-time":"2025-10-01T16:12:43Z","timestamp":1759335163831},"reference-count":0,"publisher":"Rockefeller University Press","issue":"2","content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1974,2,1]]},"abstract":"<jats:p>It has been proposed that two distinct signals are required for the triggering of the precursors of antibody-forming bone marrow-derived cells (B cells): (a) the binding of antigen or of a mitogen to the corresponding receptor sites on B-cell membranes and (b) the interaction of activated C3 with the C3 receptor of B lymphocytes. There is growing evidence that B-cell mitogens and T (thymus-derived cell)-independent antigens are capable of activating the alternate pathway of the complement system (bypass). Therefore, the effect of another potent bypass inducer was investigated with regard to B-cell activation and the role of C3. Purified, pyrogen-free cobra venom factor was mitogenic for both T and B lymphocytes (cortisone-resistant mouse thymus cells and lymph node lymphocytes from congenitally athymic mice). Venom factor could substitute for T cells by restoring the potential of antibody formation to sheep red blood cells in mouse B-cell cultures supplemented with macrophages or 2-mercaptoethanol. Venom factor may be capable of conferring activated C3 to the C3 receptor of B lymphocytes: preincubation of lymphoid cells with homologous serum or plasma, 10 mM EDTA, and sepharose-coupled venom factor converted with serum to an enzyme active against C3, inhibited their capacity to subsequently form rosettes with sheep erythrocytes sensitized with amboceptor and C5-deficient mouse complement. In the absence of EDTA, preincubation of freshly prepared B-cell suspensions with C3-sufficient homologous serum also blocked their subsequent interaction with complement-sensitized erythrocytes and at the same time rendered them reactive to an otherwise T-cell-specific mitogen. Moreover, mitogen induced B-cell proliferation in lymph node (but not in spleen) cell cultures, appeared to depend on the availability of exogenous C3: zymosan-absorbed fetal bovine serum (only 8.3% site-forming units remaining) supported T-cell activation by phytohemagglutinin, concanavalin A, and venom factor, but failed to sustain B-cell stimulation by pokeweed mitogen, lipopolysaccharide, and venom factor. T-cell-dependent antibody formation in composite cultures containing T cells or T-cell-substituting B-cell mitogens, B cells, and macrophages, always required the presence of C3-sufficient serum.<\/jats:p>","DOI":"10.1084\/jem.139.2.337","type":"journal-article","created":{"date-parts":[[2004,6,23]],"date-time":"2004-06-23T23:23:31Z","timestamp":1088033011000},"page":"337-354","update-policy":"http:\/\/dx.doi.org\/10.1084\/jem.crossmarkpolicy","source":"Crossref","is-referenced-by-count":70,"title":["COMPLEMENT-DEPENDENT B-CELL ACTIVATION BY COBRA VENOM FACTOR AND OTHER MITOGENS?"],"prefix":"10.1084","volume":"139","author":[{"given":"Peter","family":"Dukor","sequence":"first","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gebhard","family":"Schumann","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roland H.","family":"Gisler","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Manfred","family":"Dierich","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wolfgang","family":"Ko\u0308nig","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulrich","family":"Hadding","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dieter","family":"Bitter-Suermann","sequence":"additional","affiliation":[{"name":"From the Research Department, Pharmaceuticals Division, CIBA-GEIGY Limited, CH-4002 Basle, Switzerland and the Institut fu\u0308r Medizinische Mikrobiologie der Johannes-Gutenberg-Universita\u0308t, D-65 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"291","published-online":{"date-parts":[[1974,2,1]]},"container-title":["The Journal of Experimental Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/rupress.org\/jem\/article-pdf\/139\/2\/337\/1655977\/337.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/rupress.org\/jem\/article-pdf\/139\/2\/337\/1655977\/337.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,24]],"date-time":"2023-07-24T21:17:16Z","timestamp":1690233436000},"score":1,"resource":{"primary":{"URL":"https:\/\/rupress.org\/jem\/article\/139\/2\/337\/6518\/COMPLEMENT-DEPENDENT-B-CELL-ACTIVATION-BY-COBRA"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1974,2,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1974,2,1]]}},"URL":"https:\/\/doi.org\/10.1084\/jem.139.2.337","relation":{},"ISSN":["1540-9538","0022-1007"],"issn-type":[{"value":"1540-9538","type":"electronic"},{"value":"0022-1007","type":"print"}],"subject":[],"published":{"date-parts":[[1974,2,1]]}}}