Figure 1. The inflammatory response may be accompanied by a number of systemic changes referred to collectively as the acute phase response. Some of the organs participating in the response include: brain, whose involvement is reflected by fever, anorexia, somnolence and increased synthesis of CRH and ACTH; liver, which synthesizes increased amounts of metallothionein and antioxidants and which reorchestrates its pattern of plasma protein synthesis; bone, in whose marrow erythropoiesis is suppressed and thrombocytosis induced, and in which loss of bone substance occurs; the adrenal gland, in which cortisol production is enhanced by both direct and indirect stimulation; muscle, in which decreased protein synthesis and proteolysis may occur; and fat cells, which participate in alterations in lipid metabolism. Redrawn with permission from Kushner I (1993) Regulation of the acute phase response by cytokines. In: Oppenheim J, Rossio J and Gearing A (eds) Clinical Applications of Cytokines: Role in Pathogenesis, Diagnosis and Therapy. New York: Oxford University Press.

Figure 2. The acute-phase protein response is regulated both directly and indirectly by a complex network of intercellular signalling molecules involving cytokines, cytokine modulators and other hormones. Inflammation-associated cytokines, produced by cells at the inflammatory site and probably by distant cells as well, induce changes in production of acute-phase proteins by hepatocytes.