IMPROVEMENT OF THE IMMUNOGLOBULIN SUBCLASS RESPONSE TO INFLUENZA VACCINE IN ELDERLY NURSING-HOME RESIDENTS BY THE USE OF HIGH-DOSE VACCINES

To investigate the effects of age and antigen dose (10,20,60 mug) on t he immunoglobulin (sub)class distribution following influenza vaccinat ion, antibody responses in 79 elderly nursing home residents were comp ared with the responses in 100 young subjects. At a 10 mug dose the Ig M, IgG3 and IgA1 responses were comparable in both age groups, whereas the IgG, IgG, and haemagglutination inhibition (HI) responses were tw ofold lower in the elderly. A 20 mug dose increased the IgG, IgG1 and HI levels in the elderly to the levels in the young and the IgA1 to si gnificantly higher levels. A 60 mug dose increased antibody levels in the young, but did not further increase the response in the elderly. T he 20 mug dose might represent a higher level of protection in the eld erly.