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Twelve research groups participated in the ISOBM TD-3 Workshop in which the reactivity and specificity of 83 antibodies against prostate-specific antigen (PSA) were investigated. Using a variety of techniques including cross-inhibition assays, Western blotting, BIAcore, immunoradiometric assays and immunohistochemistry, the antibodies were categorized into six major groups which formed the basis for mapping onto two- and three-dimensional (2-D and 3-D) models of PSA. The overall findings of the TD-3 Workshop are summarized in this report. In agreement with all participating groups, three main antigenic domains were identified: free PSA-specific epitopes located in or close to amino acids 86-91; discontinuous epitopes specific for PSA without human kallikrein (hK2) cross-reactivity located at or close to amino acids 158-163; and continuous or linear epitopes shared between PSA and hK2 located close to amino acids 3-11. In addition, several minor and partly overlapping domains were also identified. Clearly, the characterization of antibodies from this workshop and the location of their epitopes on the 3-D model of PSA illustrate the importance of selecting appropriate antibody pairs for use in immunoassays. It is hoped that these findings and the epitope nomenclature described in this TD-3 Workshop are used as a standard for future evaluation of anti-PSA antibodies.

We reported previously that supplemental vitamin E enhances disease resistance and antibody titers and depresses bursal prostaglandin (PG) E2 in chicks. In order to determine if dietary fat composition alters PG response and interacted with vitamin E, tallow or vegetable oil high in n-6 polyunsaturated fatty acids were added to a cornsoybean meal chick diet. Comparisons were made among control cockerels and those fed diets containing safflower or corn oils or beef tallow at 3, 6 or 9% with each of these diets supplemented with 0 or 300 mg of all-rac-a-tocopheryl acetate (dla-tocophery1 acetate). In the first experiment chick antibody titers to sheep red blood cells were markedly stimulated by 6% tallow without added vitamin E. Unexpectedly, supplemental vitamin E depressed antibody titers only in the 6% tallow group. Dietary fat and supplemental vitamin E altered bursal but not splenic PGE2 values independent of inoculation. Overall, the combination of tallow and vitamin E supplementation vitamin E suppre...

The Calaveras skull, first reported in 1866, represents the earliest purported fossil human discovery in California and one of the earliest in the New World. The specimen is in the possession of the Peabody Museum, Harvard University. The validity of the original "Tertiary" age assignment was rejected by the first generation of professional American archaeologists early in the twentieth century. Radiocarbon analyses using both conventional decay counting and accelerator mass spectrometry indicate a late Holocene age for the Calaveras skull.

Microtiter immunoassays were used to determine whether a panel of 53 monoclonal antibodies submitted to the ISOBM TD-3 PSA Workshop could form assay combinations with free prostate-specific antigen (PSA) and the PSA complex with alpha1-antichymotrypsin. A panel of 6 known anti-PSA antibodies (H117, H50, H179, H164, 2E9 and 5A10) was used as labelled tracers. Epitope groups were proposed based on the ability of the Workshop antibodies to form good assay combinations with these 6 known anti-PSA antibodies. Nine of the TD-3 Workshop antibodies were found to react only with free PSA. Two additional epitope clusters were identified with 8 antibodies showing similar reactivity to antibody H117, while 11 antibodies formed a different cluster showing similar reactivity to antibody H50. Defining the nature of these immunodominant regions will be valuable in the development of more appropriate immunoassays for PSA.

The utility of circul ating mucins as breast cancer markers was first proposed by Ceriani, et al. (1) and was rapidly confirmed and expanded by many other laboratories, including those of Chu, Taylor-Papadimitriou, Hilgers and Kufe (2–5). The antibodies used in mucin assays measure epitopes expressed on or cross-reactive with the human milk-fat globule membrane (HMFG) antigens. Assays using antibodies developed in many of the above mentioned laboratories are now commercially available, and have been used with some success in moni tori ng breast cancer patients.