TR-α is expressed in osteoclasts at the osteolysis-membrane interface in patients with failed hip replacement and proposed mechanism of TR action on TNF promoter activation.

<div><p>Panel A: Photomicrographs of osteolysis interface membrane-bone sections from 2 representative patients (total n=6) and stained for anti-thyroid TR-α1 and TR-α2, demonstrating nuclear staining of osteoclasts lying on bone surfaces.</p> <p>Panel B: LPS induced activation of the -238A TNF promoter allele is facilitated by the binding of TR. In contrast, the SP1 site in the -238G allele could be occupied by SP1 even in the absence of TLR stimulus, resulting in a less inducible expression of the TNF promoter.</p>