TLR4-dependent GM-CSF protects against lung injury in Gram-negative bacterial pneumonia.

Toll-like receptors (TLRs) are required for protective host defense against bacterial pathogens. However, the role of TLRs in regulating lung injury during Gram-negative bacterial pneumonia has not been thoroughly investigated. In this study, experiments were performed to evaluate the role of TLR4 in pulmonary responses against Klebsiella pneumoniae (Kp).

Stachybotrys chartarum-induced hypersensitivity pneumonitis is TLR9 dependent.

Hypersensitivity pneumonitis (HP), an inflammatory lung disease, develops after repeated exposure to inhaled particulate antigen and is characterized by a vigorous T helper type 1-mediated immune response, resulting in the release of IL-12 and interferon (IFN)-γ. These T helper type 1 cytokines may participate in the pathogenesis of HP. Stachybotrys chartarum (SC) is a dimorphic fungus implicated in a number of respiratory illnesses, including HP.