PERSPECTIVE ARTICLE: Why do adaptive immune responses cross-react?
Article first published online: 8 DEC 2008
© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd
Special Issue: Evolutionary Medicine
Volume 2, Issue 1, pages 122–131, February 2009
How to Cite
Fairlie-Clarke, K. J., Shuker, D. M. and Graham, A. L. (2009), PERSPECTIVE ARTICLE: Why do adaptive immune responses cross-react?. Evolutionary Applications, 2: 122–131. doi: 10.1111/j.1752-4571.2008.00052.x
- Issue published online: 27 JAN 2009
- Article first published online: 8 DEC 2008
- Received: 3 October 2008 Accepted: 6 November 2008 First published online: 8 December 2008
- heterologous immunity;
- information processing;
- optimal discrimination;
- optimal immunology
Antigen specificity of adaptive immune responses is often in the host’s best interests, but with important and as yet unpredictable exceptions. For example, antibodies that bind to multiple flaviviral or malarial species can provide hosts with simultaneous protection against many parasite genotypes. Vaccinology often aims to harness such imprecision, because cross-reactive antibodies might provide broad-spectrum protection in the face of antigenic variation by parasites. However, the causes of cross-reactivity among immune responses are not always known, and here, we explore potential proximate and evolutionary explanations for cross-reactivity. We particularly consider whether cross-reactivity is the result of constraints on the ability of the immune system to process information about the world of antigens, or whether an intermediate level of cross-reactivity may instead represent an evolutionary optimum. We conclude with a series of open questions for future interdisciplinary research, including the suggestion that the evolutionary ecology of information processing might benefit from close examination of immunological data.