Journal of Clinical and Cellular Immunology
Open Access
ISSN: 2155-9899
ISSN: 2155-9899
Ontiveros-Padilla L A, Garcia-Lozano A, Pastelin-Palacios R, Arriaga-Pizano L, Isibasi A, Bonifaz L and Lopez-Macias C
Mexican Social Security Institute, Mexico
National Autonomous University of Mexico, Mexico
Posters & Accepted Abstracts: J Clin Cell Immunol
Introduction: Salmonella typhi (S. typhi) porins are important targets of the mice and human�s immune protective immune response, and are also potent immunogens capable of generating life-lasting bactericidal antibodies in mice. Mechanisms involved in this atypical antibody response remain understood. We report the activation, migration and T cell activation induction capacity of antigen-presenting cells (APC) in skin and lymph nodes in mice. Methods: Mice were immunized intradermally with porins. Epidermis of the skin was obtained 12 h post-immunization and stained with MHC-II, CD86, CD40 and PD-L1. Tissue sections were analysed by confocal microscopy. Cervical lymph nodes were obtained and prepared for a flow cytometry staining to identify dendritic cell subsets (resident and migratory) and its activation. The capacity of porin-activated APC to activate T cell responses was evaluated by co-immunising porins with inactivated Sporothrix schenckii conidia. Conidia specific memory T CD4+ cells in lymph nodes were analysed by flow cytometry and in skin by a delayed-type hypersensivity test. Results: S. typhi porins induced a higher expression of MHC-II and CD40 in skin, in contrast, CD86 and PD-L1 expression were not increased. Porins induced an increased number of CD86+ cells in skin despite CD40+ and PD-L1+ cells were not increased. Porins induced an increased number of migratory dendritic cells in lymph nodes which had an activated phenotype. Conidia specific total T CD4+ cells, central memory T CD4+ cells and effector memory T CD4+ cells, were increased in lymph nodes by porins coimmunization. The cellular response in skin induced by conidia-porins was higher. Conclusion: Intradermal immunization with S. typhi porins induced early activation of epidermal dendritic cells and recruitment of antigen-presenting cells to skin, also promoted migration of skin dendritic cells that are able to generate memory T CD4+ cells in lymph nodes and skin, inducing systemic immune responses.