Maintenance of patency after vascular trauma by topical irrigation with a peptide homologous to the carboxy-terminus of the fibrinogen gamma chain.

Synthetic peptides with amino acid sequences homologous to the carboxy-terminal sequence of the gamma chain of human fibrinogen were evaluated for their capacity to inhibit thrombus development. A 21-residue peptide effectively inhibited surface-mediated fibrin clot propagation in vitro. Since this effect was localized to the surface, we proceeded with in vivo evaluation, using site-specific topical application only. In a rat model of arterial trauma and microvascular repair, topical application of the 21-residue peptide significantly reduced the rate of thrombosis to 17%, as compared with a control rate of 83%; in comparison, a 12-residue homologue reduced the thrombosis rate only modestly to 61%, which was not significant compared with the control rate. These results indicate the feasibility of antithrombotic therapy with topically applied agents, an approach that may obviate the use of systemic anticoagulation in extremity-replantation surgery.

Prognostic value of cell surface antigens using immunoperoxidase methods in bladder carcinoma.

The presence of blood group cell surface antigens in carcinoma of the bladder has been shown to be associated with a relatively benign clinical course, whereas the absence of these antigens is often indicative of tumor recurrences and invasion. In practice, however, detection of these antigens using the SRCA test in tissue sections and urine specimens has been associated with some difficulties especially for O blood group individuals. We have used immunoperoxidase methods for detection of these tumor markers in tissue sections and/or urine specimens of normal individuals and patients with carcinoma of the bladder. The result were then compared with those obtained by SRCA test. Our present study indicates that the lectin antilectin immunoperoxidase method is a more sensitive and superior test for detecting antigen H in tissue sections as well as urine and/or bladder-washing specimens. It has clearly reduced the false negative test results and predicted subsequent recurrences and invasion more accurately in patients with bladder tumors. For best results in group A and B patients, both tests probably should be performed and compared.

Localization of human A, B and H isoantigens in Cynomolgus monkey tissues.

The presence and distribution of human A, B and H isoantigens were demonstrated in Cynomolgus monkey (Macaca fascicularis) by means of red cell adherence test. Although no human antigens were found on primate erythrocytes, various epithelial tissues revealed the presence of A, B or H antigenic substance. The distribution and localization was similar to that found in human tissues. Majority of specimens from each individual animal possessed only 1 human type isoantigen with the exception of the salivary and sweat glands, where all animals showed the presence of H antigen in addition to other specificity, and of Brunner's gland, where all sections reacted positively also for A antigen.

The cell surface antigens of bladder washing specimens in patients with bladder tumors, a new approach.

The blood group antigens A, B and O(H) are present on the cell surface of many tissues, including the urothelium. It has been shown that loss of these antigens from the surface of tumor cells correlated with subsequent development of invasion. Since the specific red cell adherence test demonstrates the presence or absence of these antigens the test may have an important prognostic and screening value. We have examined bladder washing specimens from patients with bladder tumors and normal controls for this phenomenon. The results in patients with bladder tumors were then compared to original biopsy specimens for the presence or absence of cell surface antigens. The study indicates that our technique presents a simple, reliable test that may be significant in screening as well as followup of patients with bladder cancer.

Distribution of H antigen in persons of blood groups A, B, and AB.

The distribution of H antigen in tissues of persons of blood groups A, B, and AB was examined. H antigen could be demonstrated in all tissues in which the isologous antigens A and B were demonstrated, although some cells demonstrated isologous but not H antigen. In most tissues, areas were seen that demonstrated H antigen but not the isologous antigen. This was especially true in Brunner's glands of the duodenum and esophageal glands, where the amount of H antigen was apparently greater than the amount of the isologous antigen. Since the results varied greatly from tissue to tissue, it was not possible to interpret the data with respect to the biochemical pathways of blood group antigen formation.