TLR2 and pneumococcal pneumonia: Indeed, it has been shown that the early production of proinflammatory cytokines, such as IL-6 and TNF-α, in alveolar macrophages was reduced with age in a murine pneumococcal pneumonia model, and the reduced cytokine production was due to age-related impairment in the TLR2 signaling pathway rather than expression of TLRs [27].