Molecular mechanisms of TNF-α-induced apoptosis in aging human T cell subsets

TNF-α, a pro-inflammatory cytokine, exerts its biological activity by signaling via its two receptors, TNFR-1 and TNFR-2 and by activating NF-κB. NF-κB is essential for survival of many cell types; however, TNF-α also induces cell death. During human aging TNF-α production and TNF-α-induced apoptosis are increased. In this brief review, we will discuss the TNF-α-mediated signaling and various molecular mechanisms underlying increased apoptosis in T cell subsets in aged humans with a special reference to alterations in transcription factor NF-κB and Fas-associated death domain (FADD).