D-41 Free Communication/Slide - Exercise Immunology Thursday, May 31, 2018, 3: 15 PM - 4: 45 PM Room: CC-101CD
Several published studies suggest that acute eccentric exercise can improve vaccination responses in humans. However, whether this strategy can improve sub-optimal vaccine responses in the aged is unknown. While it has been suggested that such damaging exercise acts as an inflammatory adjuvant, the mechanism behind the effect is unknown.
PURPOSE: To determine the effects of acute eccentric exercise on primary antibody and cell-mediated immune responses in young and aged mice.
METHODS: C57BL/6 male mice, aged 6-8 week (n=19) and 27 months (n=16) were randomized into either eccentric exercise (Y-ECC, A-ECC) or sedentary (Y-SED, A-SED) groups. For the Y-ECC and A-ECC groups, mice were exercised at 17m/min at -20% grade for 45 min on a treadmill. Y-SED and A-SED mice remained in their home cages. All mice were inoculated in the gastrocnemius with 100μg of OVA and 200 μg aluminum hydroxide (a suboptimal dosage based on titration experiments) immediately after the exercise. Blood was collected prior to, and one, two and four weeks after vaccination. ELISA was performed to analyze anti-OVA IgG. At three weeks post exercise, all mice were injected with 100μg OVA into the dorsal side of the right pinnae to determine the delayed-type hypersensitivity (DTH) response. Left pinnae were treated as controls. Ear thickness was measured immediately before and every 24h after intradermal injection.
RESULTS: Acute eccentric exercise did not improve primary antibody responses in either young (p=0.06) or aged (p=0.76) mice, compared to their sedentary control groups. We did not find significant differences between Y-ECC and Y-SED in their DTH responses (p=0.25). However, acute eccentric exercise enhanced DTH responses in aged mice, especially at 1 day post intradermal injection (p=0.001). We also documented a significant immunosenescent effect in antibody (p< 0.001), but not cell-mediated (p=0.813), immune responses to vaccination.
CONCLUSION: Our results suggest that acute eccentric exercise improved the cell-mediated immune response to OVA vaccination in aged, but not in young mice and failed to affect the anti-OVA antibody response in young or aged mice.