CHARACTERIZATION OF EXTRAFOLLICULAR PLASMABLAST RESPONSE IN Trypanosoma cruzi INFECTION. A

FIOCCA VERNENGO, FACUNDO; GOROSITO SERRAN, MELISA; MONTES, CAROLINA L.; GAZZONI, YAMILA; BOCCARDO, SANTIAGO; MUCCI, JUAN; GRUPPI, ADRIANA; ALMADA, LAURA; BECCARIA, CRISTIAN G; BOSSIO, SABRINA N.; ACOSTA RODRIGUEZ EVA V

Congreso; Reunión anual de Sociedades de Biociencias.; 2020

SAI, SAIC, SAFIS

CHARACTERIZATION OF EXTRAFOLLICULAR PLASMABLASTRESPONSE IN Trypanosoma cruzi INFECTIONAlmada L 1 , Gazzoni Y 1 , Fiocca Vernengo F 1 , Beccaria CG 1 , Boccardo S 1 ,Gorosito Serran M, Bossio S, Mucci J 2 , Montes CL 1 , Acosta-Rodriguez EV 1 ,Gruppi A 11 Centre for Research in Clinical Biochemistry andImmunology (CIBICI)-CONICET, FCQ-Universidad Nacional de Córdoba,Argentina2 Instituto de investigaciones Biotecnológicas (IIBIO) ? CONICET.B cells are the unique population able to differentiate intoantibody-secreting-cells (ASC). The Germinal Center reaction-GC- and theextrafollicular-EF- response generate different types of ASC which provide longandshort-term humoral immunity against infections, respectively. Theparticipation of follicular T helper cells -Tfh-, is key in these processes. In ourlab, we identified a population of EF-ASC (B220 int CD138+Blimp-1+,Plasmablasts/PB) characterized by high expression of PD-L1 and CD39,present in murine infection models but not in autoimmunity or immunizations.These PB have the capability to modulate T-cell response, since chimeramodels lacking PD-L1 hi PB have an increase in TNF-IFNγ-producingPD-1+CD4+ Tcells. The aim of our work is to characterize the phenotype ofregulatory PB and the mediators involved in the PB-Tcell interactions.Therefore, B6 mice were infected with T. cruzi and splenic, lymph node andbone marrow (BM) lymphocytes were evaluated by FACS at different days postinfection (dpi). The 99% of splenic PB expressed high levels of PD-L1 andCD39 until day 23pi and this frequency was significantly reduced from day 28pi(p