Neutrophils Which Migrate to Lymph Nodes Modulate CD4+ T Cell Response by a PD-L1 Dependent Mechanism

PISTORESI, MC

Frontiers in Immunology

Frontiers

Año: 2019

t is well known that neutrophils are rapidly recruited to a site of injury or infection andperform a critical role in pathogen clearance and inflammation. However, they are alsoable to interact with and regulate innate and adaptive immune cells and some stimuliinduce the migration of neutrophils to lymph nodes (LNs). Previously, we demonstratedthat the immune complex (IC) generated by injecting OVA into the footpad of OVA/CFAimmunized mice induced the migration of OVA+ neutrophils to draining LNs (dLNs).Here we investigate the effects of these neutrophils which reach dLNs on CD4+ T cellresponse. Our findings here strongly support a dual role for neutrophils in dLNs regardingCD4+ T cell response modulation. On the one hand, the CD4+ T cell population expandsafter the influx of OVA+ neutrophils to dLNs. These CD4+ T cells enlarge their proliferativeresponse, activation markers and IL-17 and IFN-g cytokine production. On the otherhand, these neutrophils also restrict CD4+ T cell expansio