BIOCHEMICAL AND IMMUNOLOGICAL PROPERTIES OF RELATED SMALL RUMINANT TROPHOBLAST INTERFERONS

The objectives of this study were 1) to evaluate the biochemical and i mmunological properties of caprine interferon tau (cIFN tau), 2) to de termine if intrauterine injection of recombinant ovine interferon tau (roIFN tau) extends CL life span in goats, and 3) to evaluate potentia l side effects of intramuscular (im) administration roIFN tau. Caprine IFN tau was purified, and its effects on lymphocyte proliferation wer e evaluated. Incorporation of H-3-thymidine into newly synthesized DNA was suppressed (P<0.05) by cIFN tau. Spanish goats were also fitted w ith bilateral uterine catheters at Day 7 or 8 postestrus. The received twice-daily intrauterine injections of 100 mu g roIFN tau (n=4) or ca prine proteins (n=4) from Days 14 to 18 postestrus. Intrauterine injec tion of roIFN tau extended CL life span compared with that of control goats (26.4+/-1.7 vs 17.8+/-1.9 d, respectively; P<0.01). Potential si de effects of intramuscular injections of roIFN tau were also evaluate d. Goats received 0, 1, 2 or 4 mg of roIFN tau on Days 10, 13, 16 or 1 9 of the estrous cycle. Treatment of goats with roIFN resulted in hype rthermia (P<0.01), with rectal temperatures of 40.5 degrees C recorded after 4 h and returning to normal (38.5 degrees C) after 24 h. Concom itant with the increase in rectal temperatures was a decrease (P<0.01) in plasma progesterone concentrations. Therefore, the tau interferons of goats and sheep have similar biological properties and roIFN tau h as side effects associated with other classes of interferons.