In particular, TNF-α and IL-1 signaling from macrophages triggers the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) pathway, which perpetuates the inflammatory environment of RA through a host of downstream cascades including the recruitment of additional immune cells, induction of T-cell differentiation, and increased bone resorption [21–23]. Here, TNF is linked to rheumatoid arthritis.