LIMITED IL-2 BIOAVAILABILITY DURING PEDIATRIC RSV INFECTION

SANANEZ I; RAIDEN S; ERRA DIAZ F; DE LILLO L; GONZALEZ, F; HOLGADO P; GEFFNER J; ARRUVITO L

Congreso; Reunión conjunta de sociedades de Biociencias 2017; 2017

SAI

Background: It is well known that Respiratory Syncytial Virus, despite having slight antigenic variation, repeatedly infects throughout life reflecting a defect in the development of immunological memory. In addition, we have reported that severe RSV infection of infants induced a dramatic reduction in the frequency of peripheral blood regulatory T cells (Tregs). Because IL-2 is crucial for both, the development of T cell memory and the maintenance of Tregs, we here analyzed whether the production and/or the availability of IL-2 was affected in RSV-infected children (RSV-ch). Aims: 1) to analyze if IL-2 addition increased the expression of FOXP3 in CD4+ T cells from RSV-ch; 2) to determine the ability of CD4+ T cells from RSV-ch to produce IL-2 upon in vitro stimulation; 3) to analyze the serum levels of soluble IL-2Rα (sCD25); and 4) to explore the response of CD4+ T cells from RSV-ch to sCD25. Results: Incubation of CD4+ T cells from RSV-ch with IL-2 (20 ng/ml) markedly increased the frequency of CD4+FOXP3+ T cells (p