The objective of this proposal is to study the biochemical and immunological properties of a naturally occurring, glycosylated alpha interferon produced by peri-implantation caprine conceptuses. Interferons (IFN) elicit a series of effects on their target cells that include resistance to virus, inhibition of cell growth, alterations in immune function and changes in cell-surface antigen composition. These biological effects suggest IFN may be useful in treatment of human diseases including cancer. However, a number of side effects result from recombinant human IFN treatment regimens including fever, local pain and shivering. Recombinant human IFN also reduces serum estradiol, testosterone and thyroid hormone concentrations but has a stimulatory effect on adrenal steroidogenesis. It is not known whether the conceptus interferons possess similar adverse effects. Conceptuses will be flushed from uteri on Day 18 of pregnancy and individually cultured in 100 mm petri dishes containing a total volume of 15 ml of a modified Eagle's minimum essential medium. Purification of the conceptus IFN from caprine conceptus conditioned culture medium will be accomplished using anion exchange and gel filtration chromatography. The glycosylated and nonglycosylated forms of the cTP-1 complex will be further purified using HPLC and lectin affinity chromatography. Molecular weight variants isolated from this purification schema will be tested in vitro for antiviral and antiproliferative activity. The biological relevance of the carbohydrate portion of the cTP-1 complex will be evaluated. An amino acid sequence of the cTP-1 complex will be obtained and compared to other alpha IFN. Preparations will be made to recombinantly produce this conceptus IFN.