Can current methods of immune rejuvenation improve humoral immunity against a viral infection?

Abstract

The process of aging impacts immune defense against infection. This is attributed to immunosenescence, which is defined as a gradual decline in the function of the immune system. This decline is widespread, affecting both cell-mediated and humoral immunity, which both play an integral role in pathogen recognition and elimination. Lymphoid organs are known to undergo structural and functional changes with age and understanding these changes and how they can be prevented or reversed is critical if we are to improve immunity in older adults. We studied two immune rejuvenation methods: the administration of a gonadotropin-releasing hormone antagonist, degarelix, and injection of interleukin-7:antibody complexes, and have specifically addressed their impact on humoral immunity against West Nile virus (WNV). We found that while each intervention improved certain aspects of immune cell generation and/or maintenance, neither of the two was able to improve humoral immune responses or immune defense against WNV. Results are discussed in light of current strategies for immune rejuvenation.