IMMUNOMODULATORY EFFECTS OF DIFFERENT INTRAVENOUS IMMUNOGLOBULIN PREPARATIONS IN CHRONIC LYMPHOCYTIC LEUKEMIA

COLADO, ANA; CORDINI, GREGORIO; GIORDANO, MIRTA N.; ELÍAS, ESTEBAN ENRIQUE; MORANDE, PABLO E; GAMBERALE, ROMINA; SARAPURA MARTÍNEZ, VALERIA JUDITH; BEZARES, FERNANDO R.; BORGE, MERCEDES

CABA

Congreso; LXVIII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA; 2020

Hypogammaglobulinemia is the most frequent immune defect inchronic lymphocytic leukemia (CLL). Although CLL patients usuallyhave low serum levels of IgG, IgM and IgA, most standard immunoglobulin(Ig) preparations contain > 95% of IgG. Pentaglobin is an Igpreparation of intravenous application (IVIg) enriched with IgM andIgA, with the potential benefit to restore Ig levels of all isotypes. Becausestandard IVIg preparations have well-documented immunomodulatoryeffects, we aimed to evaluate the effect of Pentaglobin(IVIgGMA) and a standard IVIg preparation (IVIgG) on leukemic andT cells from CLL patients.Peripheral blood mononuclear cells from CLL patients were used.T and B cell activation, induced by immobilized anti-CD3 mAb oranti-IgM mAb respectively, was evaluated by flow cytometry (FC).T cell proliferation in response to anti-CD3 mAb or IL-15 was determinedby FC using the CFSE dilution assay. We also evaluated byFC the effect of IVIg preparations on T and B cell apoptosis inducedby the BCL-2 inhibitor used for CLL treatment, venetoclax. Experimentswere done in presence of IVIgG, IVIgGMA or HSA (ct).We found that IVIgG impaired CD25, CD69 and PD-1 expression(n=9, p