A COMPARISON OF THE HEAT STABILITY OF LONG-ACTING THYROID STIMULATOR AND HUMAN THYROID-STIMULATING HORMONE

Abstract

SUMMARY Studies of the heat stability of a human antibody against thyroglobulin showed that after heating at 70° for 10 min. its potency was reduced to 2% of the initial value. Similarly, the potency of a preparation of long-acting thyroid stimulator (LATS) was reduced to significantly less than 10% by this treatment, whereas the potency of a human thyroid-stimulating hormone (TSH) preparation was reduced only to 45%, with a lower fiducial limit of 26% for P = 0·05. It is concluded that LATS is less stable to heat than is TSH. LATS did not differ from the antibody in heat stability.