Resumen de Innate lymphocyte/ly6Chi monocyte crosstalk promotes klebsiella pneumoniae clearance
Huizhong Xiong, James W. Keith, Dane W. Samilo
Increasing antibiotic resistance among bacterial pathogens has rendered some infections untreatable with available antibiotics. Klebsiella pneumoniae, a bacterial pathogen that has acquired high-level antibiotic resistance, is a common cause of pulmonary infections. Optimal clearance of K. pneumoniae from the host lung requires TNF and IL-17A. Herein, we demonstrate that inflammatory monocytes are rapidly recruited to the lungs of K. pneumoniae-infected mice and produce TNF, which markedly increases the frequency of IL-17-producing innate lymphoid cells. While pulmonary clearance of K. pneumoniae is preserved in neutrophil-depleted mice, monocyte depletion or TNF deficiency impairs IL-17A-dependent resolution of pneumonia. Monocyte-mediated bacterial uptake and killing is enhanced by ILC production of IL-17A, indicating that innate lymphocytes engage in a positive-feedback loop with monocytes that promotes clearance of pneumonia. Innate immune defense against a highly antibiotic-resistant bacterial pathogen depends on crosstalk between inflammatory monocytes and innate lymphocytes that is mediated by TNF and IL-17A.
