Stimulation of human blood lymphocyte by different polyclonal B cell activators of bacterial and plant origin: Production of IgM, IgG and IgA estimated by the ELISA method

Abstract

Lymphocytes isolated from peripheral blood of healthy donors were stimulated in vitro with pokeweed mitogen, concanavalin A, flagellin, Nocardia delipidated cell mitogen (NDCM) and heat-killed bacteria Escherichia coli and Actinomyces viscosus. A simple and sensitive technique, enzyme-linked immunosorbent assay (ELISA) was used for the detection of nanogram levels of IgM, IgA and IgC in media from lymphocyte cultures after polyclonal stimulation, Pokeweed mitogen, NDCM and E. coli were shown to stimulate a high production of IgM; after stimulation with A. viscosus a higher production of IgA was detected. No immunoglobulin production was observed after stimulation with polymerized flagellin.

Cytokine Production by Porcine Mononuclear Leukocytes Stimulated by Mitogens

“…Mononuclear leukocytes were separated on discontinuous gradient of Histopaque 1077 (SigmaAldrich) (Tlaskalová et al 1985).…”

In vitro immunoglobulin response of fetal B-cells is influenced by perinatal infections and antibiotic treatment: a study in preterm infants

“…All cultures were carried out with the same stock suspension of bacteria prepared before the experiment. The optimal concentration of bacteria and the length of incubation was established in our previous studies using PBMC of adult healthy humans [15] or fetal pig lymphocytes [3]. Preliminary experiments with PBMC isolated from cord blood of term healthy infants con®rmed these results.…”

“…In vitro Ig production and determination PBMC were cultivated similarly as described [15]. Brie¯y, 10 6 /ml cells were cultivated in cell culture tubes (Gama, C Ï eske BudeÏ jovice, Czech Republic) in 0.5 ml of complete RPMI 1640 medium supplemented with gentamycin (40 mg/l) and 10% fetal calf serum (Biovendor, Brno, Czech Republic).…”

“…After termination of cultivation, the cells were centrifuged (600 g, 10 min) and the culture media were frozen. The level of dierent Ig isotypes was determined by the sandwich ELISA method as previously described [15] using isotype speci®c polyclonal antibodies (Sevac, Prague, Czech Republic). Reference serum with de®ned Ig content (IgM-0.99 mg/ml, IgG-8.57 mg/ml, IgA-1.81 mg/ml; Sevac, Prague) was always applied in two-fold dilution and culture medium was used as negative control.…”

Macrophage nitric oxide synthase (NOS) activation by Nocardia opaca fractions and 15- and 56-kD isolated antigens

“…Isolated fractions of Nocardia were shown to exert adjuvant effect [2], to induce regression of experimental tumours [3][4][5][6][7], to enhance protection against irradiation [8,9], and to promote resistance to infections [10]. These activities include activation of natural killer (NK) cells and macrophages, followed by enhanced cytotoxicity of these cells and production of tumour necrosis factor-alpha (TNF-), IL-1 and other cytokines [3,[11][12][13][14][15][16][17] and stimulation of B cells to proliferation and differentiation into immunoglobulin-secreting cells [1,2,10,18,19].…”