A panel of monoclonal antibodies directed against a specific and important growth regulator is being developed. Hybridomas will be isolated, characterized, and cloned. Further characterization of the resultant monoclonal antibodies will be carried out to identify which will be most useful for (a) setting up an ELISA- based system, (b) identifying the active site of the growth regulator, and (c) purifying said protein from a recombinant system. In addition, polyclonal antibodies will be utilized t validate the feasibility of developing diagnostic assays based on the measurement of this growth regulator.The major long term commercial use of such a panel of monoclonal antibodie will be as primary reagents in a ELISA-type system to monitor treatment of postmenopausal osteoporosis, wound healing, and breast cancer; such treatment is based upon the growth regulator being developed by BioGrowth, Inc. In addition, the monoclonal antibodies can form the basis of a diagnostic test for certain growth-related disturbances and be used as research tools to better define and improve BioGrowth's product.National Institute of Allergy and Infectious Diseases (NIAID)