Immune suppressor

Benzimidazo[2,l-Z)]quinazolin-12(5//)-ones are currently receiving increased attention, as they are potent immune suppressors as well as prospective antitumor compounds, owing to the strong DNA intercalating nature of the benzimidazole and quinazolinone moieties. They have been shown to effectively truncate the propagation of human tumor cell lines. 

Furthermore we have recently demonstrated the i/-2 linked dominant genetic control of the stimulation of specific suppressor cells by immune suppressor Is) genes which appear to function in a manner similar to Ir genes. 

Approximately 180 trichothecenes are known. High moisture cereals are frequently contaminated with these toxins, considered as potent protein synthesis inhibitors and immune suppressors. Trichothecenes can produce the fatal syndrome named alimentary toxemia characterized by leucopenia (reduced white blood cell counts), multiple hemorrhages, loss of bone marrow, and esophageal cancer. In addition, the consumption of these toxins causes vomiting and reduces the efficiency of feed conversion in swine due to the considerably lower feed intake. In poultry, they cause hemorrhagic syndrome and other related problems that lower performance. 

In addition to antibodies, the immune system also consists of bone-marrow derived lymphocytes, or B cells, and T cells that come from the thymus gland, both of which (indirectly) produce antibodies. These cells, in turn, may be helped by helper cells (= H) and suppressed by suppressor cells (= S). Helper cells may be alarmed as to the presence of antigens by macrophages (= M) that eat the antigens and leave parts of their meal on their cell surface. 

The normal immune response is modeled using antibodies A, B cells, helpers H, suppressors S and antigens, or viruses, V. Each of these concentrations can be either high (= 1) or low 0). The dynamics is defined as follows ... 

Now suppose the body s immune system malfunctions and begins attacking the body itself. A typical scenario might involve killer cells K attacking helper and/or suppressor cells. Chowdbury and Stauffer [chowdQO] developed a simple five-cell model using two types of helper cells Hi and H2). two type of suppressors Si and S2) and one killer cell (K) ... 

Transforming growth factor-beta (TGF- 3) proteins are multifunctional morphogens that control cell proliferation, differentiation and apoptosis, as well as cell migration and immune surveillance. TGF-(3 acts as a tumor suppressor, but can also act as a tumor promoter in... 

SHR Spontaneously hypertensive rat SIM Selected ion monitoring SIRS Soluble immune response suppressor... 

Regulatory T cells, or suppressor T cells, suppress the activation of an immune response. The activity of these cells in organ transplant is not well elucidated. 

Schmitt, D. A., Owen-Schaub, L., and Ullrich, S. E., Effect of IL-12 on immune suppression and suppressor cell induction by ultraviolet radiation, J. Immunol. 154, 5114—5120, 1995. 

T cells are lymphocytes produced by the thymus gland. There are two types of T cells involved in immune response CD4+ (CD positive, helper cells) and CD8 (CD positive, also called T killer, or suppressor, cells). When the APCs present the antigens to CD4+ helper T cells, the secretory function is activated and growth factors such as cytokines are secreted to signal the proliferation of CD8" killer cells and B cells. When the CD8" ... 

Thus, these data indicate that similar to immature DCs, alternatively activated MO can induce immunosuppressive Tregs and that in return these Tregs are potent suppressors of MO maturation (fig. 2). Since MO bridge the innate and the acquired immune system, Tregs are able to gain influence on the innate immune system by interactions with MO. 

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