CD32 expressing CD4+ T cells during pediatric RSV infection

SANANEZ I; RAIDEN S; HOLGADO P; ERRA DIAZ F; DE LILLO L; GONZALEZ, F; URTASUN M; DAVENPORT C; CAIROLI H; GEFFNER J; ARRUVITO L

Ashville, North Caroline

Simposio; 11th International Respiratory Syncytial Viral Symposium; 2018

International RSV Symposium Committee

Background: Respiratory syncytial virus (RSV) infection represents a major burden in infants less than 12 months of age. Antibodies play a critical role in the immune response. They can act as neutralizing antibodies preventing target cell infection. Alternatively, they can interact with receptors for the Fc portion of Ig (FcR) and mediate a number of effector and immunoregulatory mechanisms. Receptors for the Fc portion of IgG (FcyR) are mainly expressed by myeloid cells as well as by NK cells and B lymphocytes. Previous studies performed in healthy adults shown that a minor fraction of CD4+ T cells (1-2%) also express FcyR II (CD32). The expression and function of CD32 on CD4+ T cells from RSV-infected infants have not been previously analyzed.Aims: 1- To analyze the expression of CD32 on CD4+ T cells from RSV severely infected infants. 2- To analyze whether CD4+ T cells bind aggregated IgG. 3 - To determine whether the expression of CD32 was associated with a particular phenotypic signature.Results: We observed an increased frequency of CD32+CD4+T cells in RSV-infected (n=22) compared with healthy infants (n=7), p