Anthrax is an acute infectious disease caused by the spore-forming bacterium Bacillus anthracis. Timely administration of antibiotics approved for the treatment of anthrax disease may prevent associated morbidity and mortality. However, any delay in initiating antimicrobial therapy may result in increased mortality, as inhalational anthrax progresses rapidly to the toxemic phase of disease.
View Article and Find Full Text PDFDevelopment of anthrax countermeasures that may be used concomitantly in a postexposure setting requires an understanding of the interaction between these products. Anthrax immune globulin intravenous (AIGIV) is a candidate immunotherapeutic that contains neutralizing antibodies against protective antigen (PA), a component of anthrax toxins. We evaluated the interaction between AIGIV and BioThrax (anthrax vaccine adsorbed) in rabbits.
View Article and Find Full Text PDFKu is a heterodimer composed of p70 and p80, and is the regulatory subunit of DNA-dependent protein kinase. As a multifunctional DNA-binding protein complex, Ku plays important roles in DNA damage repair through non-homologous end joining and in V(D)J recombination. In addition, Ku has also been implicated in various biological functions including growth control, cell proliferation, cell cycle, chromosome maintenance, transcriptional regulation, apoptosis, and viral infection.
View Article and Find Full Text PDFWe have demonstrated previously that new blood vessel formation induced by angiogenic growth factors in onplants placed on the chorioallantoic membrane (CAM) of the chick embryos is critically dependent on the cleavage of fibrillar collagen by a previously unidentified interstitial collagenase. In the present study we have used a quantitative CAM angiogenesis system to search for and functionally characterize host avian collagenases responsible for the collagen remodeling associated with angiogenesis. Among the matrix metalloproteinases (MMPs) identified in the CAM onplant tissue, the chicken MMP-13 (chMMP-13) was the only enzyme whose induction and expression coincided with the onset of angiogenesis and blood vessel formation.
View Article and Find Full Text PDFWe have previously used a subtractive immunization (SI) approach to generate monoclonal antibodies (mAbs) against proteins preferentially expressed by the highly metastatic human epidermoid carcinoma cell line, M(+)HEp3. Here we report the immunopurification, identification and characterization of SIMA135/CDCP1 (subtractive immunization M(+)HEp3 associated 135 kDa protein/CUB domain containing protein 1) using one of these mAbs designated 41-2. Protein expression levels of SIMA135/CDCP1 correlated with the metastatic ability of variant HEp3 cell lines.
View Article and Find Full Text PDFMany serine proteases play important regulatory roles in complex biological systems, but only a few have been linked directly with capillary morphogenesis and angiogenesis. Here we provide evidence that serine protease activities, independent of the plasminogen activation cascade, are required for microvascular endothelial cell reorganization and capillary morphogenesis in vitro. A homology cloning approach targeting conserved motifs present in all serine proteases, was used to identify candidate serine proteases involved in these processes, and revealed 5 genes (acrosin, testisin, neurosin, PSP and neurotrypsin), none of which had been associated previously with expression in endothelial cells.
View Article and Find Full Text PDFMammalian urokinase-type plasminogen activator (uPA) is produced as a stable single polypeptide chain zymogen and requires a distinct proteolytic cleavage to become an active, two-chain enzyme. In contrast, chicken uPA, both native and recombinant, is found predominantly as a two-chain, active enzyme even in the absence of plasmin, a physiological activator. Here we show that the proclivity to autoactivate is not a unique property of the chicken uPA catalytic domain but requires sequences distinct from and independent of the serine protease domain.
View Article and Find Full Text PDFA quantitative assessment of rate-limiting steps in metastasis has always been challenging because of the difficulty of detecting small tumor cell populations. We have developed a highly sensitive assay for monitoring the metastatic dissemination of human tumor cells in the chick embryo and used this assay to investigate the relative efficacy of sequential stages in the metastatic cascade for two malignant human tumor cells lines, HEp3 and HT1080. This assay is based on the real-time PCR amplification of human alu sequences and exhibits a high sensitivity (25 cells/lung) with a large linear range (50-100,000 cell/lung).
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