Presidential Closing Remarks 12:05 PM – 12:15 PM: Immediately Following President's Lectures ROOM: Ballroom 2/3 and Ballroom 1: B-50 Free Communication/Slide – Exercise Immunology I: WEDNESDAY, MAY 31, 2006 3:15 PM – 5:15 PM ROOM: 302
It has been suggested that physical activity has a beneficial effect on immune function; however, it is not well known whether daily physical activity affects immune response to a viral infection. Murine gammaherpesvirus-68 (MHV-68) is the mouse model for Epstein-Barr virus, which is the causative agent of infectious mononucleosis in humans. Following acute infection this virus becomes latently present for life.
PURPOSE: This study investigated the effect of eight weeks of wheel running activity on immune response to infection with MHV-68.
METHODS: At seven weeks of age C57Bl/6 mice were housed individually. One group (RUN-INFECT) had access to running wheels for eight weeks and was intranasally infected with 6000 pfu of MHV-68 at the end of the eight week period (age 15 weeks). A second group (INFECT) did not have access to running wheels and was infected with MHV-68 in a similar manner at age 15 weeks. A third group (RUN) had access to running wheels for eight weeks and was mock-infected with a saline solution at age 15 weeks. All mice were sacrificed 14 days post-infection (17 weeks of age) which corresponded to the height of latent infection. Spleens from all mice were weighed as an indirect measure of lymphoproliferation, and infectious centers assays were performed in the RUN-INFECT and INFECT groups to determine latent viral burden.
RESULTS: Spleen weights were significantly greater in the RUN-INFECT group (127.4±16.0g) and the INFECT group (152±46.3g) compared to the RUN group (76.6±5.1g, p=0.04 and p=0.003, respectively). There was no difference in spleen weight between the RUN-INFECT group and the INFECT group (p>0.05). There was no difference in the number of infectious centers in the spleen between the RUN-INFECT and INFECT groups (p>0.05).
CONCLUSIONS: The results of this study suggest that running wheel activity prior to infection with MHV-68 had little effect on immune response, as measured by lymphoproliferation and latent viral burden.