Defective T cell responses are a common feature of patients with certain infectious diseases, autoimmune disorders and cancers that differ widely in their causes and symptoms. In the October issue of Nature Immunology scientists have now identified persistent infection as the major factor linking these diverse pathologies.
Michal Baniyash and colleagues from Hebrew University, Israel, hypothesized that persistent exposure to antigen could account for the impaired T cell responses observed in different diseases. Animals persistently exposed to bacteria had poor T cell responses - examination of the T cell receptor complex showed defective zeta chain expression on the cell surface. Importantly, chronic bacterial infection reduced the ability of the animal to fight influenza infection. The authors hypothesize that zeta chain down-regulation could be a physiological mechanism that helps prevent overblown immune responses. However, it can act as a double-edged sword by impairing the ability to respond adequately to chronic diseases.
The Hebrew University of Jerusalem, Israel
Tel: +972 2 632 4653
Additional contact for comment on paper:
Instituto Scientifico HS Raffaele, Milan, Italy
Tel: +39 02 2643 2351
Also available online.
(C) Nature Immunology press release.
Message posted by: Trevor M. D'Souza