THYMIC MATURATION AND EXPORTATION OF INNATE CD8+ T CELLS TO SECONDARY LYMPHOID ORGANS (SLO)

VIANO, MARIA ESTEFANIA; BAEZ, NATALIA S.; SAVID-FRONTERA, CONSTANZA; CERBÁN, FABIO; RODRIGUEZ-GALAN, MARIA CECILIA

Congreso; LXVII Reunión Científica anual de la Sociedad Argentina de Inmunología; 2019

Sociedad Argentina de Inmunología

Innate CD8+ T cells are a subset of CD8+ T cells that have been described in mice and human. They mature in the thymus like conventional T cells and can exert a protective effect both inneoplastic and infectious processes.Our previous work demonstrated that during the acute stage of certain infections (Trypanosoma cruzi or Candida albicans), there is an increase in Innate CD8+ T cells in the thymus. This effect ismediated by the inflammatory process since we observe similar data when we induce systemic expression of IL-12 and IL-18 by hydrodynamic injection of their cDNAs.Our recent data demonstrate that Innate CD8+ T cells generated in the thymus after T. cruzi infection can be exported and accumulate in SLO up to 6 days after intrathymic staining with the dyeeFluor660 used for tracking (p<0,05).In order to evaluate the reversibility of this process, we infected mice with T. cruzi and analyzed the cellularity and phenotype of CD8+ thymocytes at day 60 post-infection, long after the acutephase of the infection (day 15), when the thymus are highly enriched on Innate CD8+ T cells.We observed that even though the cellularity and subset proportions of thymocytes are similar between control and T. cruzi-infected mice, CD8+ thymocytes still maintain some of thephenotypic characteristic of Innate CD8+ T cells like high CD122 and Eomesodermin expressions (p<0,05).The data encourage us to investigate the capacity of Innate CD8+ T cells to migrate to SLO and exert protection in different pathologic settings.