No abstract

The matrix metalloproteinases (MMPs) have been implicated in a number of diseases involving inflammation or cellular invasion.' GM 6001 (FIG. 1) is an inhibitor of most of these enzymes with Ki's in the low nanomolar range. Though potent in vitro, this molecule is short-lived in circulation with a half-life of a few minutes.We show here that topical GM 6001 prevents the infiltration of inflammatory cells into the alkali-burned rabbit cornea and into phorbol ester-stimulated mouse skin. It thus prevents ulceration in the former and psoriasis-like inflammation and proliferation in the latter. When given systemically it blocks the infiltration of cells into the peritoneal cavity of mice stimulated with thioglycollate. Topical administration of this drug inhibits angiogenesis in the chick chorioallantoic membrane. When given intravenously, it inhibits angiogenesis in rat corneas implanted with a pellet containing tumor extract, a process requiring penetration of vascular basement membrane by endothelial cells. Finally, systemic GM 6001 increases survival of mice in a B16-Fl0 melanoma metastasis model, presumably by inhibiting cellular invasion or tumor growth.In addition to the potential for preventing direct destruction of connective tissue

The genomes of three independent isolates of feline sarcoma virus (FeSV) were compared by molecular hybridization techniques. Using complementary DNAs prepared from two strains, SM-and ST-FeSV, common complementary DNAs were selected by sequential hybridization to FeSV and feline leukemia virus RNAs. These DNAs were shown to be highly related among the three independent sarcoma virus isolates. FeSV-specific complementary DNAs were prepared by selection for hybridization by the homologous FeSV RNA and against hybridization by feline leukemia virus RNA. Sarcoma virus-specific sequences of SM-FeSV were shown to differ from those of either STor GA-FeSV strains, whereas ST-FeSV-specific DNA shared extensive sequence homology with GA-FeSV. By molecular hybridization, each set of FeSV-specific sequences was demonstrated to be present in normal cat cellular DNA in approximately one copy per haploid genome and was conserved throughout Felidae. In contrast, FeSV-common sequences were present in multiple DNA copies and were found only in Mediterranean cats. The present results are consistent with the concept that each FeSV strain has arisen by a mechanism involving recombination between feline leukemia virus and cat cellular DNA sequences, the latter represented within the cat genome in a manner analogous to that of a cellular gene.

No abstract

A method is presented whereby antigenic determinants recognized by specific monoclonal antibodies can be mapped to specific sites on a protein sequence with high resolution. Short DNase I-generated DNA fragments encoding portions of the protein of interest are molecularly cloned into the EcoRI site of the fi-galactosid.Ise gene of phage A Charon 16 so as to obtain expression of randojn protein fragments as fusion proteins. The monoclonal antibody is used to screen the phage library to isolate phage expressing the specific antigenic determinant. DNA of immunoreactive phage can be analyzed rapidly and subcloned to allow DNA sequence determination.The method is generally applicable and permits antigenic determinants of functionally interesting monoclonal antibodies to be mapped and related to specific protein &equences. We have used this procedure to determine the region of the feline leukemia virus envelope protein gp7Q recognized by a virusneutralizing monoclonal antibody, cl.25. Antibocy binding was mapped to a }4-amino acid region in the amino-terminal half of gp7O. This region way be directly involved in an essential function of the gp7O protein, perhaps in gp7O-mediated host recognition functions. Synthetic peptides derived from this region may provide useful vaccine antigens for the prevention of feline leukemia viru4-ilssociated disease in cats.