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B K Choe

Publications and source records attributed to B K Choe.

At least 37 records · Page 2Linked to original sources
PubMed1981

Clinical evaluation of immunological methods for detection for serum prostatic acid phosphatase.

Evaluation of serum acid phosphatase by 3 immunochemical methods (radioimmunoassay, counterimmunoelectrophoresis and immunoenzymoassay) was done in 3 groups of patients. In 42 patients wit stage D prostatic carcinoma a comparison of serum acid phosphatase determination by colorimetric assay and the 3 immunochemical methods in samples obtained before and after initiation of therapy showed an excellent correlation among the assays. Presently, we see no advantage of the immunochemical methods over the colorimetric assay in this group of patients. Among 100 patients studied in a blind fashion to detect those with unsuspected prostatic carcinoma no such cases were found. In the last group of patients with localized prostatic carcinoma staged surgically by pelvic lymphadenectomy the only elevations of serum acid phosphatase were observed in patients with extraprostatic involvement.

Acid Phosphatase↗
PubMed1980

Immunohistological approaches to human prostatic epithelial cells.

Specific anti-acid phosphatase antisera were prepared by the use of purified prostatic acid phosphatase (PAP) from prostatic tissue and lysosomal acid phosphatase (L-AcP) from diploid fibroblast (WI-38) as antigen. Since the antigenic difference between the PAP and L-AcP was established, distribution of these enzymes among various tissues and tissue culture cells was investigated by the indirect immunofluorescence method and the unlabeled antibody method [14]. The L-AcP has been detected as granules localized in a perinuclear portion of all of the epithelial cells, fibroblasts, and peripheral blood cells except erythrocytes. Presence of the PAP was limited to the prostatic epithelial cells. It is also noted that the biosynthesis of the PAP is strikingly diminished in the long-term culture of prostatic epithelial cells. However, because of the antigenic difference between the PAP and L-AcP, and because of the high concentration of PAP in the cytoplasm of prostatic epithelial cells, it is feasible to apply the anti-PAP immunofluorescence method to the identification of metastatic prostatic carcinoma cells in the biopsy materials.

Acid Phosphatase↗
PubMed1980

Double-antibody immunoenzyme assay for human prostatic acid phosphatase.

We compare the double-antibody radioimmunoassay (RIA) and immunoenzyme assay (IEA) for measuring the concentration of prostatic acid phosphatase in human serum. Experimental details and assay performance of the two methods are outlined. Mean values for 385 normal persons were 1.02 (SD 1.32) microgram/L by IEA, 2.69 (SD 1.8) microgram/L by RIA. Results of the two methods was highly correlated [r = 0.9813, y(RIA) = 0.35 x (IEA) + 0.42, p < 0.001]. If we choose x- + 2 SD as the normal range, 3-10% false positives were seen.

Acid Phosphatase↗
PubMed1978

Bone marrow acid phosphatase in staging of prostatic cancer: how reliable is it?

To evaluate the reliability of bone marrow acid phosphatase in the staging of prostatic carcinoma we analyzed 50 bone marrow samples collected at random from the hematology service at this hospital. The samples were assayed for acid phosphatase content by a colorimetric method using sodium thymolphthalein monophosphate as a substrate and by 2 immunochemical assays developed at our laboratory (counter immunoelectrophoresis and radioimmunoassay). We found a high percentage (61 per cent) of falsely positive results in patients with various hematological diseases without evidence of prostatic carcinoma by the colorimetric evaluation. All of these patients except 1 had negative immunochemical assay. Until a specific assay for prostatic acid phosphatase is developed for clinical use we caution the use of a single elevation of bone marrow acid phosphatase as a parameter of metastatic disease.

Acid Phosphatase↗
PubMed1978

Purification and characterization of human prostatic acid phosphatase.

Human prostatic acid phosphatase (orthophosphoric monoester phosphohydrase, EC 3.1.3.2) is purified to homogeneity by standard procedures which include CM-Sephadex, Con A affinity chromatography and gel filtration. The purified enzyme is antigenically specific and has a M.W. of 100,000 with subunit M.W. of 48,000. However, the enzyme exhibited charge heterogeneity. Two major electrophoretic or chromatographic isozymic forms of PAP were separated by DEAE-Sephadex chromatography and their immunochemical identity was studied by immunodiffusion before and after the neuraminidase digestion. Quantitative precipitin and inhibition experiments showed immunological identity of the two chromatographic isozymes. Immunologic specificity of this enzyme resides on the protein moiety rather than the carbohydrate residue, although the latter group is mostly responsible for the charge group heterogeneity of the enzyme.

Acid Phosphatase↗
PubMed1978

Human prostatic acid phosphatases: I. Isolation.

A new purification procedure is described for the human prostatic acid phosphatase. The procedure included carboxy-methyl-Sephadex and Concanavalin A affinity column chromatography. The purified enzyme has a high specific enzyme activity and is free from any extraneous proteins judging from immunochemical criteria and biochemical criteria such as SDS-polyacrylamide gel electrophoresis. The purified enyzme produced a monospecific anti-PAP antisera in animals and this anti-PAP antibody did not cross-react with other human acid phosphatases.

Acid Phosphatase↗
PubMed1978

Human prostatic acid phosphatases: II. A double--antibody radioimmunoassay.

A double-antibody radioimmunoassay method for prostate-specific acid phosphatase (PAP) is presented. Experimental details are outlined to assess the reproducibility and reliability of the method under assay conditions. The upper limit of the serum PAP levels in the present assay was set at 2.4 ng/100 microliter by 162 determinations of normal serum samples. The serum PAP levels of patients with nonprostatic malignant tumors fell in the normal range, whereas the levels higher than 4.0 ng/100 microliter were found in patients with prostatic carcinoma.

Acid Phosphatase↗
PubMed1978

Human prostatic acid phosphatases: III. Counterimmunoelectrophoresis for rapid identification.

When serial dilution of standard prostatic acid phosphatases (PAP) was reacted with constant amounts of anti-PAP serum by counterimmunoelectrophoresis (CIEP), the detection end point of enzyme concentration was 0.25 ng in a 10 microliter sample volume. The PAP concentrations in unknowns can be quantitated by comparing the dilution end points of reference PAP with the testing samples. Serum PAP levels were determined by a radioimmunoassay (RIA) and CIEP using normal male and female sera and serum samples from patients with prostatic cancer and nonprostatic tumors. An excellent correlation was observed between the two assay results. According to RIA data, the concentration of PAP higher than 0.4 ng per 10 microliter (or 4.0 ng per 100 microliter) signify the elevation of serum or bone marrow PAP level beyond normal range (normal value 1.6 +/- 0.8 ng/100 microliter). Thus, the CIEP assay will be a simple and reliable screening method for the serum PAP levels in the clinical diagnosis of prostatic cancer.

Acid Phosphatase↗
PubMed1978

Expression of human prostatic acid phosphatase in a pancreatic islet cell carcinoma.

The immunologic specificity of human prostatic acidphosphatase has been established by several previous investigations as well as in this study. An apparent exception to this specificity was observed--a case of pancreatic islet cell carcinoma metastasized to the liver produced acid phosphatase that was immunologically indistinguishable from the prostatic acid phosphatase. In this case, the possibility of prostatic involvement was convincingly ruled out by clinical follow-ups and by postmortem pathologic studies. Highly purified prostatic acid phosphatase and this tumor acid phosphatase exhibited very similar Km values and identical molecular weights. Immunochemical analysis of the two enzymes using antiprostatic acid phosphatase sera showed that enzymes are antigenically identical. The implications of our observation are discussed in relation to clinical application of immunoassays for prostatic phosphatase in the future and to the molecular basis of human acid phosphatase polymorphism.

Acid Phosphatase↗
PubMed1976

In vitro senescence of mammalian cells.

This review discusses the molecular and cytokinetic aspects of cellular aging of human diploid fibroblasts. Despite a large amount of data, the basis of their limited life span has not been defined. A replicative defect in aging cells lies in the mechanism(s) that initiates DNA synthesis, and the control of this mechanism(s) is mediated through an alteration in the sythesis of specific RNA and protein molecules. Two major groups of hypotheses have been offered to explain these findings. The differentiation hypotheses are based on the concept of a 'biological clock', while error hypotheses presuppose defects in genetic transcription or translation.

Aging↗
PubMed1976

Immunology of prostatic carcinoma-an overview.

The possibility of altering the course of prostatic cancer by immunologic means requires a clear understanding of the host-tumor relationship in this disease. Available data suggest that prostatic tumors contain both prostate-specific and tumor-specific antigens, although evidence on the latter is still debatable. Patients with prostatic cancer often show nonspecific depression of their cell-mediated immunocompetence, as do patients with many other forms of cancer. The question of whether prostatic cancers are immunogenic; that is, whether they elicit a specific immunologic response, remains unanswered.

Acid Phosphatase↗