Interleukin acquired immune response

Interleukin-18 (IL-18), a recently described member of the IL-1 cytokine family, is now recognized as an important regulator of innate and acquired immune responses. IL-18 is a mediator of inflammation and ischemic tissue injury in many organs. IL-18 is con-stitutively expressed by intercalated cells of the late distal convoluted tubule, fhe connecting tubule, and the collecting duct of the healthy human kidney [229]. It is expressed at sites of chronic inflammation, in autoimmune diseases, in a variety of cancers, and in the... 

Bui, T., T. Dykers, S.L. Hu, C.R. Faltynek, and R.J. Ho, Effect of MTP-PE liposomes and interleukin-7 on induction of antibody and cell-mediated immune responses to a recombinant HIV-envelope protein. J Acquir Immune Defic Syndr, 1994. 7(8) 799-806. 

Specific cellular immunity is a type of (more specialized) acquired immunity which is based primarily on T lymphocytes. Several subpopulations of T lymphocytes are differentiated in the thymus, where one subset has identical structures on the cell surface to recognize a specific set of antigen. Each subpopulation performs different effector functions. The dominant T-cell type involved is the so-called cytotoxic T lymphocyte. In addition, T-helper cells are important for enhancing the immune response. By synthesizing and secreting various cytokines such as interferon y (INF-y or interleukin 2 (IL-2), T-lymphocytes also have an important role in controlling other major parts of the immune system. 

Causes The following causes are seen as being responsible for an acquired immune deficiency syndrome in liver cirrhosis (B.A. Runyon, 1995) (i.) hypofunction of the RES (a decrease in the filter or clearance function and phagocytosis capacity as well as reduced formation of immune modulators) (s. p. 65), (2.) reduction in hepatic synthesis of opsonins (s. p. 66), (3.) compromised function of leucocytes, (4.) impaired proliferation and activation of T lymphocytes, and (5.) increased mucosa permeability to bacteria. Both bacteria and bacterial lipopolysaccharides enter the organism in large numbers. They are responsible for increased serum levels of the cytokines (e. g. interleukins 1 and 6, TNF, y-interferon), and there is increased production of these substances together with their reduced breakdown in the cirrhotic liver. Cytokines are formed in the monocytes of blood and in the mononuclear cells of various organs (above all in ascites). 

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