Nevertheless, Sonnenberg and coworkers include assays of IL-4, IL-6, IL-12, TNF-α and β, and IFN-γ in PBMC supernatants of shuttle astronauts (G. Sonnenfeld, University of Kentucky, Louisville, personal communication, 1997). The influence of exercise on IL-1 and IL-2 and on IL-2 receptors has been reviewed by Shephard and coworkers (1995).

Natural killer cytolytic activity is assessed by measuring the in vivo release of radiolabeled chromium from target cells, usually a human myeloid tumor cell line.

Bloom, B.R., R.L. Modlin, and P. Salgame. 1992. Stigma variations: observations on suppressor T cells and leprosy. Annu. Rev. Immunol. 10:453-88.

Cannon, J.G., J.L. Nerad, D.D. Poutsiaka, C.A. Dinarello. 1993. Measuring circulating cytokines. J. Appl. Physiol. 75(4):1897-902.

Luster, M.I., C. Portier, D.G. Pait, G.J. Rosenthal, D.R. Germolec, E. Corsini, B.L. Blaylock, P. Pollock, Y. Kouchi, and W. Craig. 1993. Risk assessment in immunotoxicology. II. Relationships between immune and host resistance tests. Fundam. Appl. Toxicol. 21(1):71-82.

Luster, M.I., C. Portier, D.G. Pait, K.L. White Jr., C. Gennings, A.E. Munson, G.J. Rosenthal. 1992. Risk assessment in immunotoxicology. I. Sensitivity and predictability of immune tests. Fundam. Appl. Toxicol. 18(2):200-210.

Moldawer, L.L. 1997. The validity of blood and urinary cytokine measurements for detecting the presence of inflammation. Pp. 417-430 in Emerging Technologies for Nutrition Research: Potential for Assessing Military Performance Capability, S.J. Carlson-Newberry and R.B. Costello, eds. Committee on Military Nutrition Research, Food and Nutrition Board. Washington, D.C.: National Academy Press.

Nerad, J.L., J.K. Griffiths, J.W. Van der Meer, S. Endres, D.D. Poutsiaka, G.T. Keusch, M. Bennish, M.A. Salam, C.A. Dinarello, and J.G. Cannon. 1992. Interleukin-1 beta (IL-1 beta), IL-1 receptor antagonist, and TNF alpha production in whole blood. J. Leukoc. Biol. 52(6):687-692.

Shephard, R.J., S. Rhind, and P.N. Shek. 1994a. Exercise and the immune system. Natural killer cells, interleukins and related responses. Sports Med. 18(5):340-69.

Shephard, R.J., and P.N. Shek. 1995. Exercise, aging and immune function. Int. J. Sports Med. 16(1):1-6.

Straight, J.M., H.M. Kipen, R.F. Vogt, and R.W. Amler. 1994. Immune Function Test Batteries for Use in Environmental Health Studies. U.S. Department of Health and Human Services, Public Health Service. Publication Number: PB94-204328.

Virella, G., C. Enockson, and M. La Via. 1997. New approaches to the study of abnormal immune function. Pp. 431-450 in Emerging Technologies for Nutrition Research: Potential for Assessing Military Performance Capability, S.J. Carlson-Newberry and R.B. Costello, eds. Committee on Military Nutrition Research, Food and Nutrition Board. Washington, D.C.: National Academy Press.