Higher antibody, but not cell-mediated, responses to vaccination in high physically fit elderly.

The purpose of this study was to examine whether cardiovascular fitness, independent of confounding factors, was associated with immune responsiveness to clinically relevant challenges in older adults (60-76 yr). Thirteen sedentary, low-fit (LF; maximal O(2) uptake = 21.1 +/- 1.1 ml.kg(-1).min(-1)) and 13 physically active, high-fit (HF; maximal O(2) uptake = 46.8 +/- 3.4 ml.kg(-1).min(-1)) older adults participated in this study. Dietary intake was assessed, and a battery of psychosocial tests was administered. In vivo antibody and ex vivo proliferative and cytokine responses to influenza (Fluzone) and tetanus toxoid (TT) vaccination and delayed-type hypersensitivity skin tests were performed. HF elderly individuals displayed a higher antibody response to two of the three strains included in the Fluzone vaccine as measured by hemagluttination inhibition, but there was no difference between groups in influenza-specific ex vivo proliferation or IFN-gamma or IL-10 production. HF elderly individuals exhibited a lower IgG(1) response and a tendency for a higher IgG(2) response to the TT vaccine. There were, however, no differences in TT-specific ex vivo proliferation or IFN-gamma or IL-10 production. In contrast, HF subjects had higher proliferative responses to phytohemagluttinin. In addition, there were no differences in delayed-type hypersensitivity responses to fungal antigens between groups. These results suggest that, after accounting for confounding factors, HF elderly individuals have higher antibody responses to Fluzone vaccine and a Th2 skewing of the antibody response to TT. There was little evidence that HF mounted better cell-mediated immune responses to the Fluzone or TT vaccine measured in peripheral blood cells or to other recall antigens in vivo.

Cardiovascular exercise training extends influenza vaccine seroprotection in sedentary older adults: the immune function intervention trial.

OBJECTIVES: To determine whether cardiovascular exercise training resulted in improved antibody responses to influenza vaccination in sedentary elderly people who exhibited poor vaccine responses. DESIGN: Single-site randomized parallel-arm 10-month controlled trial. SETTING: University of Illinois at Urbana-Champaign. PARTICIPANTS: One hundred forty-four sedentary, healthy older (69.9 +/- 0.4) adults. INTERVENTIONS: Moderate (60-70% maximal oxygen uptake) cardiovascular exercise was compared with flexibility and balance training. MEASUREMENTS: The primary outcome was influenza vaccine response, as measured according to hemagglutination inhibition (HI) anti-influenza antibody titer and seroprotective responses (HI titer > or =40). Secondary measures included cardiovascular fitness and body composition. RESULTS: Of the 160 participants enrolled, 144 (90%) completed the 10-month intervention with excellent compliance ( approximately 83%). Cardiovascular, but not flexibility, exercise intervention resulted in improvements in indices of cardiovascular fitness, including maximal oxygen uptake. Although not affecting peak (e.g., 3 and 6 weeks) postvaccine anti-influenza HI titers, cardiovascular exercise resulted in a significant increase in seroprotection 24 weeks after vaccination (30-100% dependent on vaccine variant), whereas flexibility training did not. CONCLUSION: Participants randomized to cardiovascular exercise experienced improvements in influenza seroprotection throughout the entire influenza season, whereas those in the balance and flexibility intervention did not. Although there were no differences in reported respiratory tract infections, the exercise group exhibited reduced overall illness severity and sleep disturbance. These data support the hypothesis that regular endurance exercise improves influenza vaccine responses.