Mitogen-stimulated proliferation

Whole casein and individual casein fractions and their derivatives have been shown to modulate lymphocyte proliferation in vitro. Carr et al. (1990) found that asl-casein can enhance the mitogen-stimulated proliferation of murine splenic T-lymphocytes, when induced in in vitro cell culture at a concentration of 10 6 M. Wong et al. (1996b) showed that (3-casein significantly enhances the mitogen-induced proliferation of ovine T- and B-lymphocytes in a dose-dependent manner, when added to in vitro cell culture. With K-casein, on the other hand, the opposite effect was found, as K-casein was suppressive for murine... 

In the progressing lesion, a number of additional processes come into play, the most important of which are cellular necrosis with the release of foam-cell lipids to the interstitium, and the mitogen-stimulated proliferation of myointimal cells (smooth muscle cells), with the subsequent synthesis of collagens, elastin and proteoglycans. 

Pesticides also generally have suppressive effects on acquired immunity in fish. In the Beaman et al.12 study in medaka described above, malathion reduced the development of antibody-forming cells (AFC), but T cell proliferation to ConA was unaffected. Mitogen-stimulated proliferation of T- and B-lymphocytes by rainbow trout leukocytes was suppressed by in vitro exposure to endosulfan (OC), esfenvalerate (pyrethroid) or malathion, with little accompanying cytotoxicity. The doses of malathion and esfenvalerate that induced suppression were above expected tissue levels in contaminated environments, but the effective endosulfan dose was relevant to aquatic habitats83. 

TWG inhibited Concanavalin A-induced proliferation of mouse spleen cells and thymocytes in a dose-related manner. The expression of interleukin-2 (IL-2) receptors by Concanavalin A-activated spleen cells was completely inhibited by adding TWG, but IL-2 production was not completely suppressed [9], T2 at 0.1-1 pg/ml inhibited antigen- and mitogen-stimulated proliferation of T cells and B cells, IL-2 production by T cells, and immunoglobulin production by B cells. T2 did not affect IL-2 receptor expression by T cells, 1L-1 production by monocytes, or the capacity of monocytes to present antigen. Inhibition could not be accounted for by nonspecific toxicity. These results supported the conclusion that T2 exerts a powerful suppressive effect on human immune responses, and this action might account for its therapeutic effectiveness in RA [10],... 

Substances that cause cells, particularly lymphocytes, to undergo cell division. Mitogens are also referred to as polyclonal activators, since they stimulate proliferation of lymphocytes irrespective of their clonal origin. The best known mitogens are phytohemagglutinines isolated from certain plants. 

Eldridge SR, Goldsworthy TL, Popp JA. 1992. Mitogenic stimulation of hepatocellular proliferation in rodents following 1,4 dichlorobenzene administration. Carcinogenesis 13(3) 409-415. 

Albina, J. E., Abate, J. A., and Henry, W. L., Jr. (1991). Nitric oxide production is required for murine resident peritoneal macrophages to suppress mitogen-stimulated T cell proliferation Role of IFNy in the induction of the nitric oxide-synthesizing pathway. J. Immunol. 147, 144-148. 

Polybrominated Diphenyl Ethers. No studies were located regarding immunological effects in humans after oral exposure to PBDEs. No effects on pokeweed mitogen-stimulated DNA proliferation or IgG immunoglobulin synthesis were found in human lymphocytes exposed to 2,2, 4,4 -tetraBDE or 2,2, 3,4,4 -pentaBDE in vitro (Femlof et al. 1997). 

The mechanisms involved in mediating the direct actions of GH on cell proliferation are not well understood, but recent work on the induction of the c-myc protooncogene by GH has important implications [105]. Expression of this gene has been shown to follow mitogenic stimulation of various cell lines by a number of dif-... 

Bost and Pascual, 1992). In lymphocytes and lymphocytic cell lines, substance P av pients mitogen-induced proliferation of B and T lymphocytes (Payan et O.I., 1983 Bost and Pascual, 1992), stimulates immunoglobulin synthesis (Bost and Pascual, 1992), augments the release of interleukin 2 (11 2) from concanavalin A (Con A)-stimulated murine T cells (Rameshwar et al.,... 

IL-18 augments NK-cell activity in cultures of human PBMCs similar to that of the structurally unrelated cytokine IL-12. In addition, it has been found to enhance the production of IFNy and GM-CSF while decreasing the production of IL-10 by mitogen-stimulated PBMCs but had no effect on IL-4 production by concanavalin A-stimulated PBMC. lL-18 enhances T-celi proliferation apparently through an IL-2-dependent pathway. It also enhances Thl cytokine pro-duction in vitro and exhibits synergism when combined with IL-12 in terms of enhanced IFNy production but not IL-2 and GM-CSF production. ... 

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