Tonsillar germinal center reactivity regulation and aging

JULIANA PUYSSEGUR; LINDYBETH SARMIENTO VARÓN; GONZALO HUSAIN; MARIA E. ARABOLAZA; BIBIANA P. PAOLI; ELOÍSA I. ARANA

CABA

Congreso; Congreso Anual Sociedad Argentina de Inmunología; 2021

While tonsillar hyperplasia is the most frequent cause of tonsillectomy in children younger than 10, abscesses and acute infections are responsible for most tonsillectomies in teenagers. Wherever extracellular ATP (a DAMP) becomes abundant in the body, ectonucleotidases CD39 and CD73 are considered vital in the generation of an immunosuppressive microenvironment through adenosine production. Our goal was to investigate a potential metabolic adaptation of tonsillar B cells, promoting a suppressive behavior upon years of hyperplasia due to local chronic inflammation. By analyzing tonsillar mononuclear cells (TMC) using FACS, we compared co-expression of the ectonucleotidases CD73 and CD39 on CD20+ cells at different donor ages. We found that samples from older patients presented a statistically significant higher double positive CD73+ CD39+CD20+ cell population than those from younger children (37.7%  SD 10% vs 25.8%  SD 8.8% respectively, n=40, p