Production of antimicrobial peptides is preserved in aging

There is an increased susceptibility to infections during elderly, mainly because of the decreased efficacy of adaptive immunity to contain microorganisms. Albeit most of the elderly adults develop this deficiency in adaptive immunity only a minor percentage of them developed recurrent infectious diseases, thus innate immunity represents an important barrier to avoid infections in this group of aged people. Since antimicrobial peptides are important molecules of innate immunity in the study we sought to determine whether healthy aging correlates with a proper antimicrobial production. Our results by ELISA and flow cytometry showed that healthy elder individuals produce significant amounts of both cathelicidin and β-defensin-2 (hBD-2) comparable with those found in healthy young individuals. Our results suggest that during healthy aging the maintenance of the antimicrobial peptide innate immune response may be responsible for the protection against infectious diseases.