Immune activated macrophages

Male mice exposed to 7.3 mg/kg/day for 13 weeks had significantly decreased spleen weights and decreased neutrophil counts (Hoechst 1984b), indicating that immune activity in mice may also be affected. An intermediate-duration oral MRL of 0.005 mg/kg/day was derived based on the NOAEL of 0.45 mg/kg/day for immunotoxicity identified in the Banerjee and Hussain (1986) study. In support of these positive findings, Khurana et al. (1998) observed decreased macrophage functionality, in the absence of any other apparent toxicological effects, in 1-day-old broiler chicks fed 30 ppm endosulfan in the diet for 4 or 8 weeks. 

Arthur, M.J.P., Kowalski-Saunders, P. and Wright, R. (1986b). In nvo and in vitro effects of endotoxin on immune-activated hepatic macrophages. Hepatology 6, 800A. 

As with UC, the immune activation seen in CD involves the release of many proinflammatory cytokines. Cytokines thought to play major roles in CD are derived from T-helper type 1 cells and include interferon-y, TNF-a, and IL-1, IL-6, and IL-12. TNF-a is a major contributor to the inflammatory process seen in CD. Its physiologic effects include activation of macrophages, procoagulant effects in the vascular endothelium, and increases in production of matrix metallo-proteinases in mucosal cells.9,15 Excessive production of both... 

Geng YJ, Holm J, Nygren S, Bruzelius M, Stemme S, Hansson GK. Expression of the macrophage scavenger receptor in atheroma—relationship to immune activation and the T-cell cytokine interferon-gamma. Arterioscler Thromb Vase Biol 1995 15(11) 1995-2002. 

Large numbers of activated macrophages surround the solid caseous (cheese-like) TB foci (the necrotic area) as a part of cell-mediated immunity. Delayed-type hypersensitivity also develops through activation and multiplication of T lymphocytes. Macrophages form granulomas to contain the organisms. 

Non-specific immunity Peritoneal macrophage count and phagocytic activity Phagocytosis... 

As described previously, the humoral immune response results in the proliferation, activation, and subsequent production of antibodies by B cells following antigenic exposure and stimulation. The functionality and interplay between the three primary types of immune cells (macrophage, B cells, and T cells) required to elicit a humoral response can be assessed through various in vitro assays using cells from the peripheral blood or lymphoid tissues. 

Interferon-7 was the first secretory product of T cells to be discovered when it was found that supernatants derived from suspensions of T cells that had been treated with mitogenic agents could activate macrophages. This macrophage activating factor , subsequently found to interfere with the replication of viruses, was thus named interferon. The production of this compound, associated with delayed-type hypersensitivity and cell-mediated immunity, was termed immune interferon or type II interferon. With the discovery of other lymphokines with interferon-like activity (interferon-a and -j3), the compound was finally designated interferon-7. 

The immunostimulating activity of chitosan has also been reported. A 70% DD chitosan showed immunostimulating effects by activating macrophages and natural killer cells in rats when infected with . coli and Sendai virus (Nishimura et al., 1984). Chang et al. (2004) also reported the immune-enhancing effects of chitosan as a novel adjuvant to an inactivated influenza vaccine, and the antibody content in serum remarkably increased the antiviral defenses of mice. 

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