CHARACTERIZATION OF CYTOKINE SECRETING B CELL SUBPOPULATIONSIN HUMAN TONSILS

DE ROSA, JAVIER ENRIQUE; LINDYBETH SARMIENTO VARON; ARIEL BILLORDO; PLACIDA BAZ ; PABLO FERNANDEZ; ANDRES BLANCO ; KARINA PASQUEVICH ; ELOÍSA ARANA

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017; 2017

Sociedades Biocientíficas. Sociedad Argentina de Inmunología.

Tonsils are secondary lymphoid organs which must grant immunologic protection against pathogens and tolerance against inoffensive Ags in air and food. They are mostly B-cell (Bc) maturation and differentiation sites. Bc are able to secrete multiple cytokines under different stimuli, independently of their role as Ag presenting and Ab producing cells. It is likely that alteration of the immune equilibrium activation/regulation may trigger recurrent tonsillitis (RT) and/or hypertrophy (HT) leading in turn to tonsillectomy. Hence, the aim of our work was to characterize such unconventional immunefunctions of tonsillar Bc, i.e different Bc subsets with regulatory and pro-inflammatory profiles, within the human oropharyngeal cavity. All measurements were done by FACS. We determined tonsillar Bc expression of IL6, IL8, IFN, IL5, TNF, IL21, IL10 and TGFat different time-points post stimulation. Also, we established the kinetics of appearance of IL10 (regulatory cytokine) expressing Bc (B10) and compared it with that of pro-inflammatory cytokine-expressing Bc (IL6 and IL8) for 5 patients upon 0; 16; 32 and 72 hs stimulation, via TLR9 and CD40L. The proportion of B10 increased between 16 and 72 hs in all cases. Notably, the percentage of B10 detected at the different time points depended on the cause of surgery, an issue that is addressed in a different poster in the same Congress. The results varied across individuals; hence, we showed the contour plots of a single patient and graph lines plotting the results of 5 different patients for the cytokine kinetics. Importantly, we also found a relevant proportion of IL17-expressing B cells in tonsils which is, to our knowledge, the first time that is reported in literature. Collectively, these results demonstrate that despite disease-associated changes, Bc from those damaged tonsils preserve their immune competence to secrete a number of cytokines. This study advances our understanding of the immune functions of the tonsils