Chen-Yu Tsai, Min Xie, Melissa Cristaldo, Gabriella R Peluso, Joshua Woo, Frank Nuritdinov, Narineh M Odjourian, Maureen Dougher, Rosleine Antilus-Sainte, Kaj M Kreutzfeldt, Sabine Ehrt, Martin Gengenbacher
Bacille Calmette-Guérin (BCG) provides limited protection against tuberculosis relapse. We investigated whether adjunctive immunotherapy targeting B cells enhances BCG-mediated protection in a murine model of latent tuberculosis. While BCG alone had modest effects, adjunctive immunotherapy with recombinant APRIL significantly reduced relapse. Protection was associated with selective remodeling and activation of marginal-zone B cell compartments, whereas effects on T cell populations were comparatively modest. These findings support further investigation of B cell-targeted immunomodulation to improve durable immune control and reduce tuberculosis relapse.