Lipopolysaccharide mitogenicity

Humoral-mediated immunity LPS (lipopolysaccharide) mitogen response or F(ab)2 mitogenic response enumeration of plaques by IgM antibody-forming cells to a T-dependent antigen (sheep red blood cells serum IgM concentration... 

Kim, G-Y, KimJ-H, AhnS-C et al. 2004. Lycopene suppresses the lipopolysaccharide-induced phenotypic and functional maturation of murine dendritic cells through inhibition of mitogen-activated protein kinases and nuclear factor NF-kappa B. Immunology 113 203-211. 

Arrighi, J.F.et al., A critical role for p38 mitogen-activated protein kinase in the maturation of human blood-derived dendritic cells induced by lipopolysaccharide, TNF-alpha, and contact sensitizers. J. Immunol., 166, 3837, 2001. 

Mitogen responses of lymphoid cells (phytohaemagglutinine (PHA), concanavalin A (Con A) as T cell mitogens, lipopolysaccharide (LPS) as B cell mitigen)... 

The various organs of the immune system such as spleen, lymph nodes, thymus and bone marrow containing the cells involved in the various immune responses offer the possibility to harvest these cells and perform in vitro assays for evaluation of effects on the immune system. When part of an in vivo animal study this may indicate a direct toxic effect of pharmaceuticals, that is, immunosuppression (Table 18.2). So, it is feasible to obtain cell suspensions for further evaluation such as determination of cellular subsets of T and B leukocytes by fluorescent activated cell sorter analysis (FACS analysis), and determination of natural killer (NK) cell activity of the spleen cell population. An advantage of this approach is that it may lead to identification of a biomarker to be used in clinical studies. In addition, in vitro stimulation of spleen cells with mitogens activating specific subsets may indicate potential effects on the functionality of splenic cell populations. Concanavalin A (Con A) and phytohemagglutinin (PHA) activate Tcells, while lipopolysaccharide (LPS) activates primarily B cell populations. Blood is collected for total white blood cell (WBC) determination and blood cell differential count. In addition, serum can be obtained for determination of serum immunoglobulins. 

The mitogenic effect of lipopolysaccharide on bone marrow-derived mouse lymphocytes. Lipid A as the mitogenic part of the molecule. J. Exp. Med., 137, 943-953... 

Thus, lipopolysaccharides are potent pyrogens in man and rabbits. Furthermore, they are mitogens for B-lymphocytes (mouse) and they induce lethal toxicity in various experimental animals (.7). The lipoprotein (IS. coli) is also a B-cell mitogen it is, however, devoid of pyrogenicity and lethal toxicity (6). K-antigens and the enterobacterial common antigen lack all of these latter activities. 

Slomiany B.L. and Slomiany A. (2002) Disruption in gastric mucin synthesis by Helicobacter pylori lipopolysaccharide involves ERK and P38 mitogen-activated protein kinase participation. Biochem Biophys Res Commun 294, 220-224 Snapp E., Altan N. and Lippincott-Schwartz J. (2003) Fluorescence Recovery After Photo-bleaching. In Current Protocols in Cell Biology. (Bonifacino, J., Dasso, M., Harford, J., Lippincott-Schwartz, J., Yamada K., Morgan K.S., eds.) Unit 21.1 John Wiley Sons, Inc., New York... 

Wright, S.D., Ramos, R.A., Tobias, P.S., Ulevitch, R.J., Mathison, J.C. CD14, a receptor for complexes of lipopolysaccharide (LPS) and LPS binding protein. Science 249 (1990) 1431-1433. Yang, H., Young, D.W., Gusovsky, F., Chow, J.C. Cellular events mediated by lipopolysaccharide-stimulated toll-like receptor 4. MD-2 is required for activation of mitogen-activated protein kinases and Elk-1. J Biol Chem 275 (2000) 20861-20866. 

Leblanc Y, Roy P, Boyce S et al. (1999) SAR in the alkoxy lactone series the discovery of DFP, a potent and orally active COX-2 inhibitor. Bioorg Med Chem Lett 9 2207-2212 Lee SH, Soyoola E, Chanmugam P et al. (1992) Selective expression of mitogen-inducible cyclooxygenase in macrophages stimulated with lipopolysaccharide. J Biol Chem 267 25934-25938... 

Hu LF, Wong PTH, Moore PK, Bian JS (2007) Hydrogen sulfide attenuates lipopolysaccharide-induced inflammation by inhibition of p38 mitogen-activated protein kinase in microglia. JNeurochem 100 1121-1128... 

Mitogen-activated protein kinase (MAPK) p38o is a member of a family of Ser/Thr-spe-cific protein kinases that are activated upon exposure of cells to mitogens such as bacterial lipopolysaccharide or environmental stresses such as exposure to UV irradiation or chemical... 

Several processes in the immune response are affected by lithium in vivo and in vitro 139). The proliferative responses of hamster lymphoid cells to concanavalin A or phytohemagglutinin, which stimulate mitosis in T cells, were enhanced by lithium in a serum-free culture system. Proliferative stimulation also was obtained with lithium using the B cell mitogen lipopolysaccharide, but the B cell mitogens dextran sulfate and trypsin had no effect 140-143). Lithium increased the effects of suboptimal concentrations of stimulants, but had smaller effects on stimulation by optimal concentrations. With concanavalin A, the response to optimal stimulatory concentrations was inhibited 140). Paradoxical results such as these may be due to inhibitory effects of lithium on adenylate cyclase, or to effects on membrane transport systems 141). Most of these experiments used very high concentrations of lithium, considerably in excess of normal therapeutic doses (maximal inhibitory concentrations were 10 mM with hamster cells and 5 mM with human lymphocytes). At therapeutic levels of lithium, increased incorporation of [ H]thymidine was seen in human peripheral blood mononuclear cells. 

Coutinho A, Forni L, Melchers F, Watan-abe T. 1977. Genetic defect in responsiveness to the B cell mitogen lipopolysaccharide. Eur. J. Immunol. 7 325-28... 

Fessler MB, Malcolm KC, Duncan MW, Worthen GS. A genomic and proteomic analysis of activation of the human neutrophil by lipopolysaccharide and its mediation by p38 mitogen-activated protein kinase. J Biol Chem 2002 277(35) 31291-302. 

Control of expression Constitutive Rapidly inducible inflammation, IE-1, TNE TGE- S mitogens, lipopolysaccharides Constitutive in some tissues... 

Switching to classes other than IgD is most obvious in activated B cells. Extensive studies have been performed on mouse B cells that have been polyclonally activated by bacterial lipopolysaccharide (LPS) [2,16-18] or by both LPS and switch factors , i.e. certain lymphokines produced by T lymphocytes [6-9]. Antigen stimulation in vitro (e.g. [19]) and mitogenic stimulation of human B cells (e.g. [20])... 

Nagano S, Otsuka T, Niiro H, Yamaoka K, Arinobu Y, Ogami E, Akahoshi M, Inoue Y, Miyake K, Nakashima H, Niho Y, Harada M Molecular mechanisms of lipopolysaccharide-induced cyclooxygenase-2 expression in human neutrophils Involvement of the mitogen-activated protein kinase pathway and regulation by anti-inflammatory cytokines. Int Immunol 2002 14 733-740. 

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