Frontiers in Immunology (Jul 2022)

IL-10 Overexpression After BCG Vaccination Does Not Impair Control of Mycobacterium tuberculosis Infection

  • Catarina M. Ferreira,
  • Catarina M. Ferreira,
  • Consuelo Micheli,
  • Consuelo Micheli,
  • Palmira Barreira-Silva,
  • Palmira Barreira-Silva,
  • Ana Margarida Barbosa,
  • Ana Margarida Barbosa,
  • Mariana Resende,
  • Mariana Resende,
  • Mariana Resende,
  • Manuel Vilanova,
  • Manuel Vilanova,
  • Manuel Vilanova,
  • Ricardo Silvestre,
  • Ricardo Silvestre,
  • Cristina Cunha,
  • Cristina Cunha,
  • Agostinho Carvalho,
  • Agostinho Carvalho,
  • Fernando Rodrigues,
  • Fernando Rodrigues,
  • Margarida Correia-Neves,
  • Margarida Correia-Neves,
  • Margarida Correia-Neves,
  • António Gil Castro,
  • António Gil Castro,
  • Egídio Torrado,
  • Egídio Torrado

DOI
https://doi.org/10.3389/fimmu.2022.946181
Journal volume & issue
Vol. 13

Abstract

Read online

Control of tuberculosis depends on the rapid expression of protective CD4+ T-cell responses in the Mycobacterium tuberculosis (Mtb)-infected lungs. We have recently shown that the immunomodulatory cytokine IL-10 acts intrinsically in CD4+ T cells and impairs their parenchymal migratory capacity, thereby preventing control of Mtb infection. Herein, we show that IL-10 overexpression does not impact the protection conferred by the established memory CD4+ T-cell response, as BCG-vaccinated mice overexpressing IL-10 only during Mtb infection display an accelerated, BCG-induced, Ag85b-specific CD4+ T-cell response and control Mtb infection. However, IL-10 inhibits the migration of recently activated ESAT-6-specific CD4+ T cells into the lung parenchyma and impairs the development of ectopic lymphoid structures associated with reduced expression of the chemokine receptors CXCR5 and CCR7. Together, our data support a role for BCG vaccination in preventing the immunosuppressive effects of IL-10 in the fast progression of Mtb infection and may provide valuable insights on the mechanisms contributing to the variable efficacy of BCG vaccination.

Keywords