1. Janeway, C. and Travers, P. 1997. Immunobiology: The Immune System in Health and Disease, 3rd edn, p. 11:1. Garland, London.
2. Murphy, K. M. 1998. T lymphocyte differentiation in the periphery. Curr. Opin. Immunol.10:226.
3. O'Garra, A. 1998. Cytokines induce the development of functionally heterogeneous T helper cell subsets. Immunity8:275.
4. Mosmann, T. R. and Sad, S. 1996. The expanding universe of T-cell subsets: Th1, Th2 and more. Immunol. Today17:138.
5. Borish, L. and Rosenwasser, L.J. 1998. Cytokines in allergy inflammation. In Middleton, E. J., Reed, C. E., Ellis, E. F., Adkinson, N. F., Jr, Yunginger, J. W. Jr and Busse, W. W., eds, Allergy Principles and Practice, 5th edn, p. 108. Mosby, St Louis, MO.