Biological Clocks and Immune Function  

When we have an infection, we feel ‘sick’ in large part because of our immune system’s response to the infectious organism, not because of the infection per se.  Moreover this impact of the immune system on our physiology and behavior varies markedly depending on the time-of-day or time-of-year that the immune system is activated. Indeed, circadian and seasonal rhythms in morbidity and mortality are well-documented in human and nonhuman populations, but the relative contribution of changes in the host immune system to such patterns are not fully understood. 

 Our research in this domain aims to specify the neural and endocrine mechanisms by which seasonal time information causes profoundly different motivational and behavioral responses to illness at different times of the day and year.

Recent published work from our lab has described:
       
Pineal and gonadal-hormone dependence of seasonal changes in immune function [PubMed]
       
Neural targets for the action of melatonin in regulating seasonal changes in immunity [PubMed]
        
Changes in immune and HPA axis function in laboratory rats [PubMed]

Effects of photoperiod history on adaptive immune responses and HPA axis function [PubMed]

Enhancement of endotoxin tolerance in winter [PubMed]        

Click on the topics/links above to access these papers via PubMed.