Mitogenic Activity Of Lipopolysaccharide Research Articles

Evaluation of the proliferative activity of immunocompetent cells in the jejunal and iliac lymph nodes of prepubertal female wild boars diagnosed with mixed mycotoxicosis

Abstract The study evaluated the proliferative activity of immunocompetent cells in the jejunal and iliac lymph nodes of prepubertal female wild boars exposed to deoxynivalenol and zearalenone in naturally contaminated feed. The evaluation was performed with the use of the MTT assay and 2 mitogens: lipopolysaccharide (LPS) and concanavalin A. Intensified proliferative processes in T and B lymphocytes were revealed. The mitogenic activity of LPS was more expressed in the lymphocytes of both iliac and jejunal lymph nodes in comparison with the control group. Proliferative activity was higher in iliac lymph nodes than in jejunal lymph nodes. A reverse trend was observed in the percentage of live cells, which was higher in jejunal lymph nodes during the evaluation of lymphocyte proliferation.

A new pharmacological testing method--different effects of levamisole and the serum of mice orally treated with levamisole on mitogenic activity of lipopolysaccharide.

The direct addition of levamisole to murine splenic lymphocytes had no effect on the mitogenic activity of lipopolysaccharide. However, the addition of serum of mice orally treated with levamisole increased the mitogenic activity, and this increased activity using serum was similar to the result obtained in an in vivo experiment. These results suggest that the new in vitro experimental method using serum may be able to reproduce the in vivo effect of drugs.

Effect of shosaikoto, a japanese and chinese traditional herbal medicinal mixture, on the mitogenic activity of lipopolysaccharide: A new pharmacological testing method

Two in vitro experimental systems were compared to evaluate the pharmacological effects of Shosaikoto, a Japanese and Chinese traditional herbal medicinal mixture, on the mitogenic activity of lipopolysaccharide (LPS) using murine splenic cell culture. The first system involved the addition of serum obtained from mice treated orally with Shosaikoto while the second system involved the direct addition of Shosaikoto to the medium. Both systems were performed in parallel. Prednisolone decreased the mitogenic activity of LPS in a dose-dependent manner in both experimental systems. On the other hand, the serum of mice pretreated with Shosaikoto increased the mitogenic activity of LPS with constant cell viability, although the serum showed no mitogenic activity in the experiment without LPS. When Shosaikoto was added to the medium directly at more conventional doses, the mitogenic activity of LPS was elevated with an increase of cell viability. In the experimental system without LPS, Shosaikoto itself showed mitogenic activity. In other experiments, the mitogenic action of LPS was investigated using spleen cells of mice orally pretreated with Shosaikoto for 7 days. Mitogenic action of LPS was increased in the spleen cells of Shosaikoto-treated mice compared with the control. However, in the same experimental system without LPS, mitogenic action was not recognized in the spleen cells of Shosaikoto-treated mice.

Effects of five kampohozais on the mitogenic activity of lipopolysaccharide, concanavalin A, phorbol myristate acetate and phytohemagglutinin in vivo

Mitogenic activity of lipopolysaccharide (LPS), concanavalin A (Con A), phorbol myristate acetate (PMA) and phytohemagglutinin (PHA) were investigated using spleen cells prepared from C57BL/6 mice orally pretreated with one of five kampohozai extracts (Shosaikoto, Daisaikoto, Hochuekkito, Juzendaihoto and Tokishakuyakusan). Shosaikoto and Daisaikoto elevated the mitogenic activity of LPS and reduced those of Con A. The mitogenic activities of PMA and PHA were elevated by low doses of Shosaikoto and Daisaikoto and suppressed by high doses. Juzendaihoto and Tokishakuyakusan showed no effect on the mitogenic activity of LPS and Con A, but increased those of PMA and PHA. Hochuekkito increased the mitogenic activity of LPS, Con A, PMA and PHA. In the absence of mitogens, these five kampohozais showed no mitogenic activity. These results indicate that the kampohozais used in this experiment appear to possess the immunomodulating or immunostimulating activities that might be expected from clinical experiences in Japan and China.

Lipopolysaccharides from Bacteroides fragilis are mitogenic for spleen cells from endotoxin responder and nonresponder mice.

The lipopolysaccharides (LPS) from Bacteroides fragilis are structurally atypical and give weak responses in most tests of endotoxic activity, but the mitogenic activity of LPS from B. fragilis has not been tested. We prepared LPS from B. fragilis 23745 by three methods and compared their mitogenic activity for murine spleen cells with that of LPS from Escherichia coli K235 prepared by similar techniques. LPS extracted from B. fragilis with hot phenol-water, with butanol-water, or by detergent separation from the outer membrane were mitogenic for spleen cells from C57BL/10ScN, C57BL/10ScCR, and C3H/HeJ mice. The outer membrane, the outer membrane protein-polysaccharide complex, and the capsular polysaccharide from B. fragilis were also mitogenic for spleen cells from the same murine strains. LPS extracted from E. coli K235 with hot phenol-water, butanol-water, or sodium deoxycholate were mitogenic for C57BL/10ScN spleen cells, but only the LPS extracted with butanol and deoxycholate were stimulatory for spleen cells from C57BL/10ScCR and C3H/HeJ mice. Two types of LPS varying in the 2-keto-3-deoxyoctonate-to-carbohydrate ratio were isolated from E. coli K235 with sodium deoxycholate; both endotoxins contained protein which was typical of lipid A or endotoxin protein. These results indicate that the LPS from B. fragilis is a potent mitogen for spleen cells from endotoxin responder and endotoxin nonresponder mice.

Mitogenic response of C3H/HeJ mouse lymphocytes to polyanionic polysaccharides obtained from Bordetella pertussis endotoxin and from other bacterial species.

Lipopolysaccharide extracted from Bordetella pertussis was mitogenic for spleen cells of endotoxin-resistant C3H/HeJ mice. Although endotoxic lipid A was inactive, mitogenic activity of lipopolysaccharide was exhibited by purified preparations of polysaccharides I and II, which constitute the carbohydrate moiety of the macromolecule. These low-molecular-weight (2,800 and 3,600) polysaccharides, containing carboxyl groups, were not mitogenic for thymocytes and splenic T-cells of C3H/HeJ mice, but did show mitogenic activity for splenic B-cells of C3H/HeJ mice and for spleen cells of C57BL/6 athymic nude mice. The mitogenic activities of polysaccharides I and II were also compared with those of other polyanionic polysaccharides, and the results indicate that high molecular weight is not necessary, and negative charges are not sufficient, for mitogenicity.

Differentiation of Lymphoid Cells: B Cell As a Direct Target and T Cell As a Regulator in Lipopolysaccharide-Enhanced Induction of Immunoglobulin Production

The cells involved in the stimulatory effect of bacterial lipopolysaccharide (LPS) on the induction of immunoglobulin (Ig) production by rabbit spleen cells cultured in the absence of antigen has been analyzed. Addition of LPS caused a several-fold enhancement of both DNA synthesis and Ig production. These enhanced activities were not significantly affected by depletion of adherent cells in the spleen cell population. Although inactivation of splenic T cells by anti-thymocyte serum (ATS) treatment did not affect the enhancement of DNA synthesis due to LPS, such treatment did adversely affect the enhancement of Ig production by LPS. Furthermore, the enhancement of Ig production of ATS-treated spleen cells by LPS was found to be dependent on the number of thymocytes added. In addition, the prior incubation of ATS-treated spleen cells with LPS resulted in effective enhancement of Ig production when such ATS-treated spleen cells and thymocytes were combined after removal of LPS. An identical experiment, except that thymocytes instead of ATS-treated spleen cells received the prior incubation with LPS, did not result in enhancement of Ig production. Finally, the enhanced Ig production due to LPS was inhibited by hydroxyurea, a known inhibitor of cellular DNA synthesis. The relationship between the mitogenic activity of LPS on B cells, the regulatory function of T cells, and the enhancement of Ig production by LPS is discussed in relation to the contrasting reports concerning the cellular target of LPS.

Summary of Discussion

Dr. Barnet M. Sultzer opened the discussion by expanding on aspects of his work referred to by Dr. Gdran M611er. He noted that there is a variant strain of C3H mice whose spleen cells are low responders to the mitogenic activity of lipopolysaccharides (LPS). Preliminary work has shown that these mice have a deficiency in B-cell lymphocytes that is specific for endotoxin. An exchange between Dr. Werner Braun and Dr. M611er established that most of the endotoxins used by Dr. Mbller were alkali-treated for reduction of toxicity. In reply to a question by Dr. S. A. Broitman, Dr. John W. Jutila stated that he had not assessed