TLR4 and infection: The peptidoglycan-recognition protein has a strong affinity for Gram-positive bacteria and can also bind with Gram-negative bacteria to initiate signaling via IMD and the Toll pathway [49], whereas the suppressor of cytokine 2 is a well-known negative regulator of the JAK-STAT pathway, which checks the activity of this pathway during infection and development [50,51,52,53].