F-17 Free Communication/Slide - Immunology Friday, May 29, 2015, 1: 00 PM - 2: 45 PM Room: 30A
Several published reports suggest that acute eccentric exercise can improve vaccination responses in young and old adults, especially if they are sub-optimal (Pascoe et al. Brain Behav Imm, 2014). The mechanisms are unclear but hypothesized to occur due to an inflammation-induced adjuvant effect on the immune response. In order to understand the mechanisms responsible for this effect, verification of this potential beneficial effect needs to be replicated in an animal model.
PURPOSE: To determine the effects of acute eccentric or concentric exercise on the antibody response to vaccination in mice.
METHODS: Balb/c male mice, aged 6 weeks (n=20) were randomized into one of three groups: concentric exercise (CON, n=7), eccentric exercise (ECC, n=6) or sedentary (SED, n=7). Initially, for the CON group, mice were exercised at 17m/min speed at +5% grade for 60 minutes on a treadmill. No electrical shock was used. The ECC group exercised at the same speed and duration but at -20% grade. After 24 hours, another bout of exercise was repeated. We have shown that this ECC protocol induces muscle damage and local inflammation in mice (Boppart et al, Am J Physiol Cell Physiol, 2011). All mice were intramuscularly inoculated in the gastrocnemius with 25μg (suboptimal dose from prior titration) of ovalbumin (OVA) and 200 μg aluminum hydroxide as adjuvant in 50μl sterile saline immediately after the second bout of exercise. Blood was collected before (pre) and one, two and four weeks after vaccination from the retro-orbital vein. Plasma anti-ovalbumin IgG was determined using ELISA procedures.
RESULTS: We found a significant time main effect (p<0.001) indicating a significant increase in anti-OVA IgG at 1, 2 and 4 weeks relative to pre-vaccination. Interestingly, we found a significant time x treatment interaction (p=0.04) and a trend towards a treatment main effect (p=0.08) indicating that ECC exercise responses were blunted when compared to CON and SED, especially at the 4 week time point.
CONCLUSION: We conclude, given the parameters of our study, that acute ECC or CON exercise does not improve antibody responses to vaccination in young mice when administered immediately after exercise. Future experiments will address whether acute exercise can improve vaccine responses in animals exhibiting impaired immunity (e.g. aged).