concanavalin-a and lobenzarit

The cellular mechanism of action of a newly developed drug, CCA, N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt, on PHA-, autologous mixed lymphocyte reaction (AMLR)-, and phorbol myristate acetate (PMA)-stimulated T-cell proliferation was investigated. Addition of 50 micrograms of CCA per milliliter suppressed PHA- and AMLR-stimulated T-cell proliferation. In contrast, CCA failed to suppress PMA-stimulated macrophage-depleted T-cell proliferation. After treatment of T cells or macrophages with CCA for 12 h, recombined T cells and macrophages were stimulated with phytohemagglutinin. [3H]Thymidine incorporation by T cells was suppressed when macrophages but not T cells were treated with CCA. These results indicate that CCA suppresses T-cell proliferation by acting on macrophages. The mechanism involved in this suppression of CCA was due to the loss of Ia antigen on macrophages and the loss of interleukin-1 (IL-1) secretion from macrophages.

Topics: Adjuvants, Immunologic; Cells, Cultured; Concanavalin A; Histocompatibility Antigens Class II; Humans; Immunosuppressive Agents; Interleukin-1; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Macrophages; ortho-Aminobenzoates; Phytohemagglutinins; T-Lymphocytes; Tetradecanoylphorbol Acetate

We explored the population of Interferon-gamma (IFN-gamma) containing cells in order to clarify their cell surface phenotypic markers. Here we define gamma-IFN containing cells as gamma-IFN plaque forming cells (PFC). By this method, it was found that IFN-gamma containing cells consist of two cell fractions, i.e., OKT3+, OKT4+, and OKT8- cells and OKM1+ cells. Effective IFN-gamma production seems to require participation of plastic-adherent cells (presumably monocytes), while the addition of cyclosporin A (CyA) almost completely blocked generation of human IFN-gamma. To characterize Con A-stimulated IFN-gamma containing cells, we performed two-color flow cytometry using FACS IV. Most of the IFN-gamma containing cells have surface phenotypic markers for Leu3, Leu8, Leu15, HLA-DR, and IL-2 receptors, but most lack markers for Leu2 and Leu7. Interestingly, most of Leu3+ and IL-2 receptor+ cells belong to the dimly illuminating cell fractions of the IFN-gamma containing cell population. Our results indicate that IFN-gamma containing cells are heterogeneous with respect to surface phenotypic markers but the predominant IFN-gamma containing cell type is the helper T cell (OKT4+). Lastly, OK432, glycyrrhizin, and CCA (lobenzarit disodium) increase the number of IFN-gamma containing cells and are thought to be immunomodulators.

Topics: Antibodies, Monoclonal; Antigens, Surface; Concanavalin A; Cyclosporins; Glycyrrhetinic Acid; Glycyrrhizic Acid; Humans; Interferon-gamma; Leukocytes; Monocytes; ortho-Aminobenzoates; T-Lymphocytes, Helper-Inducer

Keyhole lympet hemocyanin (KLH)-specific suppressor T (Ts) cells that suppress the in vitro secondary anti-trinitrophenyl (TNP) PFC response to TNP-KLH could be induced when murine spleen cells were precultured with KLH. N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt (CCA) at 1-100 micrograms/ml augmented the in vitro induction of Ts cells when the cells were precultured with a suboptimal dose of KLH (10 micrograms/ml). Ts cell-induction was, however, rather slightly inhibited by the same concentrations of CCA when the lymphocytes were precultured with an optimal amount of KLH (100 micrograms/ml). In the in vivo experiments, the daily administration of 10 mg/kg CCA for 4 weeks augmented or inhibited Ts cell-induction when mice were immunized with a suboptimal (30 micrograms/body) or an optimal (100 micrograms/body) amount of KLH, respectively. However, CCA had no effect on the induction of Ts cells by concanavalin A in vivo. On the other hand, CCA augmented the induction of helper T (Th) cells both in vitro and in vivo when Th cells were induced with a suboptimal amount of antigens. In contrast, the augmentative effect was no longer observed when Th cells were induced by an optimal amount of antigens. These results suggest that CCA is a compound showing immunomodulating properties that affect Ts and Th cell-induction depending on immunological conditions. These immunopharmacological profiles are discussed in connection with its clinical application to an autoimmune disease like rheumatoid arthritis.

Topics: Animals; Antibody Formation; Concanavalin A; Female; In Vitro Techniques; Mice; Mice, Inbred BALB C; ortho-Aminobenzoates; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

Topics: Animals; Autoimmune Diseases; Concanavalin A; Female; Kidney Diseases; Lipopolysaccharides; Mice; Mice, Inbred Strains; ortho-Aminobenzoates; T-Lymphocytes; Time Factors