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Biomedical subjects

L D Papsidero

Publications and source records attributed to L D Papsidero.

43 records · Page 3Linked to original sources
PubMed1980

Isoelectric focusing--a new approach to the study of immune complexes.

Isoelectric focusing was used to examine antigen-antibody complexes. BSA : anti-BSA complexes were dissociated and antigen was separated from antibody based upon differences in pI value by isoelectric focusing (pH gradient 3--10). The recovered proteins were homogeneous as determined by immunodiffusion and polyacrylamide gel electrophoresis analyses. The technique was capable of resolving 6.4 microgram of BSA : anti-BSA complexes. More than 90% of the complexes applied to isoelectric focusing gels were dissociated and entered the gels. It was further demonstrated, by the use of complexes containing enzymes (acid phosphatase or alkaline phosphatase), that the dissociated enzymes retained their native pI as well as enzymatic activities. The isoelectric focusing technique, therefore, represents a new and effective approach to the dissociation of antigen-antibody complexes.

Animals↗
PubMed1980

Quantitation of prostate-specific antigen in serum by a sensitive enzyme immunoassay.

A sensitive sandwich-type enzyme immunoassay has been developed for quantitation of a human prostate-specific antigen (PA). With this method, PA at a concentration as low as 0.10 ng/ml can be detected. The assay was reproducible as within and between assays yielded a coefficient of variation of 5.7% and 4.6%, respectively. Only human prostate tissues (n = 31) were shown to contain PA. No PA was detected in other human normal or tumor tissues (n = 13). PA was not detectable in sera from normal females (n = 17) or female cancer patients (n = 25). A mean +/- S.D. of 0.47 +/- 0.661 ng/ml (ranging from less than 0.10 to 2.6) ws obtained from a group of 51 normal males. Sera from male patients with nonprostatic cancer contained a similar range of PA as that of normal males. Patients with prostate cancer (371 of 442) and benign prostatic hypertrophy (13 of 19) were shown to have elevated levels of circulating PA. Although no quantitative difference in PA levels was found between the benign prostatic hypertrophy group and Stage A of prostatic cancer, patients with Stages C and D prostatic cancer exhibited significantly elevated levels of PA qualitatively and quantitatively. These results therefore indicate that PA is a histiotypic product of the prostate and may be of use as an adjunctive tool in diagnostic procedures of prostate cancer.

Antigens↗
PubMed1980

Isolation of prostatic acid phosphatase-binding immunoglobulin G from human sera and its potential for use as a tumor-localizing reagent.

A human immunoglobulin that binds prostatic acid phosphatases (PAP) was isolated from the serum of normal individuals by affinity chromatography using a PAP-Sepharose solid adsorbent. The yield of isolated protein, termed PAP-binding globulin (PAPBG), ranged from 4.7 to 16.3 microgram/ml serum. As shown by immunoelectrophoresis, PAPBG is a gamma-globin of restricted electrophoretic heterogeneity. PAPBG was shown to bind radiolabeled PAP by radioimmune precipitation, and an association constant of 5.0 x 10(4) M-1 was calculated. As determined by immunofluorescence, PAPBG was shown to react with human prostatic tumor cell lines. No binding was detected to other tumor cells examined including those from cultures of human breast, thyroid, pancreas, or normal fibroblasts.

Acid Phosphatase↗
PubMed1980

A prostate antigen in sera of prostatic cancer patients.

A prostate antigen has been detected by a rocket immunoelectrophoresis technique in 17 of 219 sera obtained from patients with advanced prostatic cancer. Sera from 175 patients with nonprostatic cancers, including those with late-stage disease of the breast, lung, colon, rectum, stomach, and pancreas, were antigen negative as were 20 samples each from normal adults and age-matched males. Antigen in sera showed immunological identity with antigen in prostate tissue as determined by immunoprecipitation peak enhancement experiments. Using antibody affinity chromatography and radioimmunoprecipitation techniques, the antigen in sera was purified and subjected to sodium dodecyl sulfate electrophoresis; it exhibited a molecular weight of approximately 36,000, similar to that of antigen isolated from prostatic tissue.

Acid Phosphatase↗
PubMed1979

Immune complexes in breast cancer patients as detected by C1q binding.

Levels of Clq binding activity have been measured in the sera of patients with benign and malignant breast disease. Cancer patients showed significantly higher binding activity than patients with gross fibrocystic disease. Clq binding levels were not related to levels of carcinoembryonic antigen, or rheumatoid factor. The Clq reactive material was identified as being precipitable with Protein A, and predominantly eluted in gel filtration fractions with a molecular weight of approximately 1 x 10(6). These studies indicate that Clq binding level may be of use in the differential diagnosis of benign and malignant breast disease.

Antibodies, Neoplasm↗
PubMed1978

Identification of a breast tumor-associated orosomucoid by concanavalin A affinity chromatography.

Con A-Sepharose affinity chromatography was utilized to examine the glycoproteins in phosphosaline extracts of normal and breast tumor tissues and breast patient sera. In extracts of normal breast tissue, normal sera and patient sera, all glycoproteins were eluted from the Con A-Sepharose with a linear gradient of 0.0-0.5 M alpha-methylmannose. Using breast tumor extracts, a glycoprotein peak which could not be eluted as with normal tissue extracts was observed. This tightly-binding peak could be eluted from the Con A-Sepharose with acetate buffer containing 1.0 M KCl. Polyacrylamide electrophoresis of this tightly-binding glycoprotein peak revealed one major glycoprotein and four minor glycoproteins. The major glycoprotein obtained from electrophoresis represented about 60% of the Con A-Sepharose tightly-binding protein and reacted with antiserum to human orosomucoid (alpha 1-acid glycoprotein). All glycoproteins isolated from tumor tissue extracts appeared to represent normal serum constituents as they were retained on an immunoadsorbent containing antibodies to normal serum proteins. The possible significance of the isolated tumor-associated orosomucoid is discussed.

Adenocarcinoma↗