) INNATE IMMUNITY AGAINST TRYPANOSOMA CRUZI IN IMMUNIZED ANIMALS IS AFFECTED BY SEXUAL DIMORPHISM

CAMILA BULFONI BALBI; MA. FLORENCIA PACINI; BRENDA DINATALE; FLORENCIA GONZÁLEZ; ELIANA BORGNA; ESTEFANIA PROCHETTO; CECILIA FARRÉ; GUSTAVO CHAPO; IVÁN MARCIPAR; GABRIEL CABRERA; ANA ROSA PÉREZ

Mar del Plata

Congreso; LXX REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA (SAI) & 3ER CONGRESO FRANCO-ARGENTINO DE INMUNOLOGÍA (FAIC); 2022

Sociedad Argentina de Inmunologia

Vaccine efficacy may be modulated by different parameters like sex,among others; so, the inclusion of both sexes becomes relevant.Typically, vaccine studies against T. cruzi (Tc) have been focusedon adaptive response evaluation. We previously showed that anasal vaccine formulated with Trans-sialidase (TS) plus c-di-AMPwas immunogenic, in terms of adaptive response, while females (F)showed better responses than males (M). Here we aim to evaluatepossible variations in the innate response induced in F and M infected BALB/c mice previously immunized with our vaccine. We mainlyfocused on cells resembling myeloid-derived suppressor cells (rMDSC). For this, mice (n=5/group) were intranasally immunized in 3doses, one every 2 weeks with 10 µg of TS emulsified in c-di-AMPadjuvant (TS+c-di-AMP). Other groups of mice were treated withsaline (S), TS or c-di-AMP alone. Fifteen days after the last immunization, mice were orally challenged with 3000 Tc. Both rMDSC lineages (rG-MDSC: CD11b+Ly6C+/lowLy6G+; rM-MDSC: CD11b+Ly6C+/lowLy6G-) were evaluated at 21 days post-infection (dpi) by flow cytometry. Parasitemia and clinical score were recorded until 50 dpi.Overall, M mice showed increased parasitemias compared to theanalogous groups of F (i.e.,17 dpi TS+c-di-AMP, p