Production of TNF-alpha ex vivo is predictive of an immune response to flu vaccination in a frail elderly population.

ABSTRACT

OBJECTIVE: To investigate the relationship between the response to influenza vaccination and the ability to produce proinflamatory cytokines in elderly subjects. METHODS: Whole blood samples from 25 elderly subjects collected before influenza vaccination were stimulated with the influenza vaccine in order to evaluate the secretion of five specific cytokines TNFα, IFNα, IFNγ, IL2 and IL10. The results were correlated with the increased HAI antibody titres two weeks after vaccination. RESULTS: Only 30% of elderly individuals seroconverted after vaccination. Although 50 to 70% of the cohort did not produce TNFα, IFNα, IFNγ, IL2 or IL10, all of the individuals who seroconverted were able to produce TNFα. Furthermore production of IFNγ, with or without production of IFNα/ß, was not associated with a better response to the vaccine. CONCLUSION: Production of TNFα appears to be primordial for an efficient vaccine response, and may provide a predictive marker for the humoral response to vaccination. It may also provide the basis for evaluating agents designed to rescue TNFα-producing cells. This study emphasises a need to rescue TNF-producing cell function.