Concurrent infection with <i>Mycobacterium tuberculosis</i> confers robust protection against secondary infection in macaques

by Anthony M. Cadena, Forrest F. Hopkins, Pauline Maiello, Allison F. Carey, Eileen A. Wong, Constance J. Martin, Hannah P. Gideon, Robert M. DiFazio, Peter Andersen, Philana Ling Lin, Sarah M. Fortune, JoAnne L. Flynn

For many pathogens, including most targets of effective vaccines, infection elicits an immune response that confers significant protection against reinfection. There has been significant debate as to whether natural Mycobacterium tuberculosis (Mtb) infection confers protection against reinfection. Here we experimentally assessed the protection conferred by concurrent Mtb infection in macaques, a robust experimental model of human tuberculosis (TB), using a combination of serial imaging and Mtb challenge strains differentiated by DNA identifiers. Strikingly, ongoing Mtb infection provided complete protection against establishment of secondary infection in over half of the macaques and allowed near sterilizing bacterial control for those in which a secondary infection was established. By contrast, boosted BCG vaccination reduced granuloma inflammation but had no impact on early granuloma bacterial burden. These findings are evidence of highly effective concomitant mycobacterial immunity in the lung, which may inform TB vaccine design and development.

Tratto da:
Note sul Copyright: Articles and accompanying materials published by PLOS on the PLOS Sites, unless otherwise indicated, are licensed by the respective authors of such articles for use and distribution by you subject to citation of the original source in accordance with the Creative Commons Attribution (CC BY) license.