Enhanced Antimicrobial Peptide Response Following Bacillus Calmette-Guerin Vaccination in Elderly Individuals

• Published in: Vaccines (Basel) 2024-09, Vol.12 (9), p.1065
• Main Authors: Pandiarajan, Arul Nancy, Kumar, Nathella Pavan, Rajamanickam, Anuradha, Bhavani, Perumal Kannabiran, Jeyadeepa, Bharathi, Selvaraj, Nandhini, Asokan, Dinesh, Tripathy, Srikanth, Padmapriyadarsini, Chandrasekharan, Babu, Subash
• Format: Article
• Language: English
• Subjects: Aged; Antigens; Antimicrobial peptides; Antitubercular agents; Bacillus; Bacillus Calmette-Guerin vaccine; Bacterial infections; BCG; BCG vaccination; BCG vaccines; Circulation; Clinical trials; COVID-19 vaccines; Defensins; Demographic aspects; Dosage and administration; Enzymes; Evaluation; Health aspects; Infections; Leukocytes (neutrophilic); Mortality; Neutrophils; Older people; Pandemics; Patient outcomes; Peptides; Performance evaluation; Physiological aspects; Plasma; Plasma cells; Plasma levels; Population; Population (statistical); Severe acute respiratory syndrome coronavirus 2; Tuberculosis; Vaccination
• ISSN: 2076-393X; 2076-393X
• DOI: 10.3390/vaccines12091065

Antimicrobial peptides are an important component of host defense against Mycobacterium tuberculosis. However, the ability of BCG to induce AMPs as part of its mechanism of action has not been investigated in detail. We investigated the impact of Bacillus Calmette-Guerin (BCG) vaccination on circulating plasma levels and TB-antigen stimulated plasma levels of AMPs in a healthy elderly population. We assessed the association of AMPs, including Human Beta Defensin 2 (HBD-2), Human Neutrophil Peptide 1-3 (HNP1-3), Granulysin, and Cathelicidin (LL37), in circulating plasma and TB-antigen stimulated plasma (using IGRA supernatants) at baseline (pre-vaccination) and at Month 1 and Month 6 post vaccination. Post BCG vaccination, both circulating plasma levels and TB-antigen stimulated plasma levels of AMPs significantly increased at Month 1 and Month 6 compared to pre-vaccination levels in the elderly population. However, the association of AMP levels with latent TB (LTB) status did not exhibit statistical significance. Our findings indicate that BCG vaccination is linked to heightened circulating levels of AMPs in the elderly population, which are also TB-antigen-specific. This suggests a potential mechanism underlying the immune effects of BCG in enhancing host defense against TB.