TNF and common variable immunodeficiency: Bridging the innate and adaptive immune response pathways, the regulatory role of Toll-like receptors (TLRs) in CVID has been investigated, and the results pointed to an impaired TLR9-mediated signaling and IFN-α production as well as reduced generation of tumor necrosis factor (TNF)-α following induction of TLR4 expression [40].