Human- and mouse-inducible nitric oxide synthase promoters require activation of phosphatidylcholine-specific phospholipase C and NF-kappa B.

Background: The production of nitric oxide by type II inducible nitric oxide synthase (type II NOS) gene is controlled at least in part by transcriptional activation. Although the murine and human type II NOS genes share significant sequence homology, they differ in the induction stimuli required for activation.

Materials And Methods: The A549 human and murine RAW 264.

Increased activation of isolated intestinal lamina propria mononuclear cells in inflammatory bowel disease.

Normal human lamina propria lymphocytes are in a heightened state of activation compared with peripheral blood with regard to cell-surface activation antigen expression (transferrin receptor, interleukin-2 receptor, 4F2) and the increased spontaneous secretion of immunoglobulins in vitro. This study evaluates the cell-surface expression of activation-associated antigens in different subpopulations of isolated colonic lamina propria mononuclear cells in inflammatory bowel disease. In pilot studies using three-color flow cytometry, autofluorescence was observed that was emitted by unstained lamina propria mononuclear cells, which interfered with both the sensitivity and the specificity of the analyses.

Human rib bone marrow mononuclear cells spontaneously synthesize and secrete IgE in vitro.

We have examined spontaneous secretion of IgE by human rib bone marrow mononuclear cells (MNC). Bone marrow MNC from nine out of 12 rib specimens synthesized and secreted substantial amounts of IgE during 14 days of in vitro culture. The 14-day supernatants from these bone marrow MNC contained a mean of 2589 pg/ml of IgE (n = 12) with a maximum production of 15,408 pg/ml of IgE compared with small amounts of IgE (80-200 pg/ml) produced by similarly cultured normal and inflammatory bowel disease intestinal lamina propria MNC.

Bovine IgG1, but not IgG2, binds to human B cells and inhibits antibody secretion.

We previously observed that milk-derived bovine IgG, but not serum-derived bovine IgG, strongly inhibits antibody secretion by pokeweed mitogen (PWM)-stimulated human peripheral blood mononuclear cells (PBMC). Bovine milk contains a greater percentage of IgG1 (90%) than does bovine serum (53%). To determine whether bovine IgG subclasses have different functional capabilities, we have examined the effects of bovine IgG1 and IgG2 subclasses upon not only antibody secretion but also mitogenesis by human PBMC.

Inhibition of antibody secretion by 5-aminosalicylic acid.

We have examined the effects of sulfasalazine and its metabolites sulfapyridine and 5-aminosalicylic acid on antibody secretion by normal peripheral blood and intestinal mononuclear cells. Sulfasalazine and 5-aminosalicylic acid both inhibited pokeweed mitogen-stimulated secretion of immunoglobulins (Igs) A, G, and M by peripheral blood mononuclear cells in a dose-dependent manner, whereas sulfapyridine had little effect. Sulfasalazine and 5-aminosalicylic acid also inhibited spontaneous secretion of IgA by intestinal mononuclear cells, but sulfapyridine did not.