Toll interacting protein, also known as TOLLIP, is an inhibitory adaptor protein .It is an inhibitory adaptor protein within Toll-like receptors (TLR). The TLR pathway is a part of the innate immune system that recognizes structurally conserved molecular patterns of microbial pathogens, leading to an inflammatory immune response.

Compared with the full-length isoform, 2 of the human proteins lack the N-terminal TBD, and 1 lacks the C2 domain. A mouse-specific isoform lacks the C-terminal CUE domain. EST database analysis suggested that full-length human TOLLIP is ubiquitously expressed. Expression of the other human variants appeared to be more restricted, with evidence for enrichment in brain.