Tamm-Horsfall protein in lymph nodes.

We found masses of amorphous waxy pale staining material in the peripheral sinuses of lymph nodes removed with renal tumors. The material was histochemically and immunohistochemically identical to Tamm-Horsfall protein. It was found also in tubular casts, renal tubules, and intrarenal lymphatics in the resected kidneys. Tamm-Horsfall protein was restricted to the compressed residual kidney and was not seen in the tumors. Under certain circumstances Tamm-Horsfall protein escapes from the tubules into the renal interstitium and may produce a local inflammatory reaction. It also gains access to intrarenal lymphatics and thence to regional lymph nodes. This may be relevant to the evolution of an antibody response.