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Abstract
From October 1991 to December 1992, 144 patients with bleeding peptic ulcer and stigmata of recent hemorrhage were included in a study designed to investigate, by means of endoscopic examinations repeated at 2-day intervals, the evolutionary development of stigmata of recent hemorrhage, such as visible vessels, and to determine the time required for each type of stigma to fade. Eighty-five patients underwent endoscopic follow-up until the stigmata had disappeared. A visible vessel takes about 4.1 +/- 2.1 days to disappear, requiring significantly more time than an adherent clot or an old stigma, which take 2.4 +/- 0.8 days and 2.4 +/- 1.3 days, respectively (p < .05). Bleeding does not recur after stigmata disappear. Time required for stigmata to fade is not affected by age, sex, smoking, history of peptic ulcer, ulcer location, severe bleeding, underlying systemic disease, or endoscopic local therapy. While healing, stigmata of recent hemorrhage evolve through a sequence of phases: a visible vessel may or may not appear as an adherent clot and then as a red or black flat spot before disappearing.
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Affiliation(s)
- C C Yang
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
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52
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Sheu BS, Shin JS, Chen KW, Lin XZ, Lin CY. Endoscopic removal of a large intragastric foreign body with an overtube: a case report. Zhonghua Yi Xue Za Zhi (Taipei) 1994; 54:193-7. [PMID: 7954062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
After amphetamine ingestion, a 39-year-old male attempted suicide by swallowing glass trifles, cigarette lighter and razor blades. All foreign bodies ingested were evacuated spontaneously and smoothly within one week, except for the 10-cm long lighter, which was removed by endoscopy via supplementary overtube with moderate difficulty. The subsequent clinical course was uncomplicated. More than 80% of the ingested foreign bodies which reach the stomach can be eliminated uneventfully through the gastrointestinal tract. The remainder may cause complications such as obstruction, perforation and hemorrhage. Usually the locations of obstruction are over the three anatomic narrowings of the esophagus, the pyloric ring and ileocecal valve. Perforation occurs with ingestion of long, sharp, metallic pointed objects or animal bones, and is more frequent among those who had previous abdominal surgery or intestinal diseases. Endoscopic removal as soon as possible is suggested for high risk groups, with use of the overtube method to prevent complications.
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Affiliation(s)
- B S Sheu
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, R.O.C
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53
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Hsu PI, Lin XZ, Chan SH, Lin CY, Chang TT, Shin JS, Hsu LY, Yang CC, Chen KW. Bleeding peptic ulcer--risk factors for rebleeding and sequential changes in endoscopic findings. Gut 1994; 35:746-9. [PMID: 8020797 PMCID: PMC1374870 DOI: 10.1136/gut.35.6.746] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
From September 1991 to December 1992, a prospective study was conducted to determine the risk factors and residual risk of rebleeding, and the evolutionary endoscopic changes in peptic ulcers that rebled. Emergency endoscopies were performed on 452 patients with haematemesis or a melaena, or both within 24 hours of admission. If the lesions were actively bleeding, then the patients were treated with injection sclerotherapy. A multivariate analysis of clinical, laboratory, and endoscopic variables of 204 patients with ulcer bleeding showed that hypovolaemic shock, a non-bleeding visible vessel, and an adherent clot on the ulcer base were independently significant in predicting rebleeding (p < 0.05). Considering these three factors according to the estimates of their regression coefficients showed that a non-bleeding visible vessel was the strongest predictor of rebleeding. The study of the residual risk of rebleeding after admission showed that most rebleeding episodes (94.1%), including all associated with hypovolaemic shock, surgical treatment, and death, occurred within 96 hours of admission. After this time, the residual risk of rebleeding was less than 1%. Study of the changes in endoscopic findings before and after rebleeding illustrated that all ulcers with a visible vessel or adherent clot showed at follow up endoscopy were derived from ulcers with initial major stigmata. It is concluded that hypovolaemic shock, a non-bleeding visible vessel, and an adherent clot on an ulcer base are of independent significance in predicting rebleeding. Observation for 96 hours is sufficient to detect most rebleeding episodes after an initial bleed from peptic ulcer.
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Affiliation(s)
- P I Hsu
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
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54
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Chen KW, Wu MH, Huang JJ, Yu CY. Bilateral spontaneous pneumothoraces, pneumopericardium, pneumomediastinum, and subcutaneous emphysema: a rare presentation of paraquat intoxication. Ann Emerg Med 1994; 23:1132-4. [PMID: 8185113 DOI: 10.1016/s0196-0644(94)70116-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Pneumothorax, subcutaneous emphysema, and pneumomediastinum occur frequently in critically ill patients in association with blunt or penetrating injuries or other conditions while performing Valsalva-like maneuvers. We present the case of a patient with bilateral pneumothoraces, pneumomediastinum, pneumopericardium, and subcutaneous emphysema after acute paraquat intoxication.
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Affiliation(s)
- K W Chen
- Department of Emergency Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China
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55
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Abstract
Although emphysematous pyelonephritis has been recognized for more than a hundred years, the actual etiology is still unknown. Glucose fermentation has been implicated as a mechanism of gas formation. We report a case of emphysematous pyelonephritis in which real-time ultrasonography demonstrated intravascular gas bubbles originating in the involved kidney, and passing into the inferior vena cava and hepatic veins. Gas from the affected kidney was analyzed by chromatography; the result showed hydrogen 10.5%, carbon dioxide 39%, nitrogen 49.6% and oxygen 0.8%. The clinical presentation and the results of gas analysis implicate a critical condition that bacteria proliferated rapidly by mixed acid fermentation of glucose. Additionally, the finding of gas production and transportation could explain the previous hypothesis of gas transport. In this critical situation immediate drainage with medical intervention is indicated to treat this life threatening condition.
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Affiliation(s)
- K W Chen
- Department of Emergency Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China
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56
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Chen KW, Juang JH, Huang HS, Lin JD, Huang BY, Huang MJ. Effect of gliclazide on plasma lipids and pancreatic beta cell function in non-insulin-dependent diabetes mellitus. Changgeng Yi Xue Za Zhi 1993; 16:246-50. [PMID: 8313208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Eighteen patients with non-insulin-dependent diabetes mellitus (NIDDM), who were newly diagnosed or had their oral hypoglycemic agents discontinued for more than 3 months, were studied to evaluate the effect of gliclazide on glycemic control, plasma lipids and beta cell function. The mean fasting plasma glucose (249 +/- 11 vs 170 +/- 10 mg/dl, p < 0.001), postprandial plasma glucose (353 +/- 16 vs 237 +/- 16 mg/dl, p < 0.001) and HbA1C (9.6 +/- 0.4 vs 6.5 +/- 0.3% p < 0.001) decreased significantly after 3-months of gliclazide treatment. The beta cell function showed a significant increase in fasting serum C-peptide (1.8 +/- 0.2 vs 2.1 +/- 0.3 ng/ml, p < 0.05) and an insignificant increment in serum C-peptide after glucagon stimulation (2.2 +/- 0.3 vs 2.2 +/- 0.4 ng/ml, p < 0.1). In 8 cases with an initial serum cholesterol above 200 mg/dl, the serum cholesterol decreased significantly (236 +/- 8 vs 200 +/- 12 mg/dl, p < 0.05). However, LDL-cholesterol (164 +/- 8 vs 145 +/- 13 mg, p > 0.05) and HDL-cholesterol (66 +/- 5 vs 54 +/- 9 mg, p > 0.05) showed insignificant decrease after gliclazide therapy. In 4 patients with hypertriglyceridemia, the serum triglyceride decreased (441 +/- 161 vs 239 +/- 73 mg/dl, p > 0.1), but this was not statistically significant. These findings suggest that hyperglycemia, fasting serum C-peptide levels and hypercholesteremia are significantly improved after a 3-month period of gliclazide therapy in NIDDM patients.
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Affiliation(s)
- K W Chen
- Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C
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57
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Chen KW, Tsai YL, Chen WS, Lee CY. Enzyme immunoassay for prostate-specific antigen and its diagnostic application in prostate cancer. J Formos Med Assoc 1992; 91:1039-43. [PMID: 1283838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The purpose of this study was to develop a reliable screening test for prostate cancer. Monoclonal antibodies specific to the prostate-specific antigen (PSA) were generated with an improved hybridoma technique. The hybrid cells were initially cultured in a semisolid medium containing methylcellulose and later transferred to a liquid medium for further subculture. Thirty-six out of a total 1,250 recovered colonies were shown to exhibit a high affinity to PSA by radioimmunobinding assay. Eight hybrid cell lines which secreted either IgG1 or IgG2a antibodies of a high affinity and specificity were established for evaluation. The association constants between PSA and these monoclonal antibodies were shown to range from 1 x 10(9) to 5 x 10(9) M-1. From the results of a matrix cross-matching procedure, pairs of monoclonal antibodies were identified and the corresponding epitopes assigned, and most of them could also be paired with rabbit anti-PSA in a typical sandwich enzyme immunoassay. The designated EIA procedure was performed over 90 minutes at room temperature in a two-stage incubation protocol with a sensitivity of 0.4 ng/mL. The EIA kit was shown to have little cross-reactivity with thyroid stimulating hormone, alpha-fetoprotein, carcinoembryonic antigen and prostate acid phosphatase. Preliminary evaluations with clinically defined patients' sera revealed that proper selections of antibody pairs in sandwich immunoassays are crucial to the adequate performance of the EIA kits.
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Affiliation(s)
- K W Chen
- Department of Obstetrics and Gynecology, Provincial Tao-Yuan Hospital, Taiwan, R.O.C
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58
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Abstract
PURPOSE Acute bacterial nephritis (ABN) represents localized, nonliquefied renal infection, and the subsequent alteration of tissue densities can be readily detected by computed tomography (CT). In recent literature, a variety of renal parenchymal alterations observed on CT were reported. However, previous reports on the clinical course of ABN were inconsistent and lacked correlation with radiologic findings. In this investigation, we attempt to correlate the severity of clinical manifestations with CT findings in ABN and draw some conclusions regarding the natural history, pathophysiology, and clinical management of this disease. PATIENTS AND METHODS From July 1988 to June 1991, 30 cases of ABN were evaluated at our institute. On the basis of postcontrast-enhanced CT findings, 28 cases were grouped into (1) Group I (7 cases), wedge-shaped lesions (focal or diffuse); (2) Group II (12 cases), focal mass-like lesions; and (3) Group III (9 cases), diffuse (multifocal) mass-like lesions. The clinical features and outcomes of the three groups were compared. The positive detecting rates and clinical usefulness of ultrasonographic (US) and urographic examinations were also studied in each group. RESULTS An excellent correlation can be demonstrated between the clinical parameters (including underlying diseases, maximum temperature and leukocyte count, duration of fever, flank pain, leukocytosis, and pyuria; the incidence of septic shock, diabetic ketoacidosis, and acute renal failure; and outcome) and the pattern of renal parenchymal abnormalities detected on CT. The clinical features in Group I patients displayed many similarities with those in uncomplicated acute pyelonephritis (APN) reported previously, and responded to antibiotic therapy promptly. Most patients in Group II were successfully treated with antibiotics but had a protracted clinical course with a slower clinical improvement than Group I. Only one case with a Group II lesion was noted to progress to renal abscess formation and extrarenal involvement. In comparison, 33% of the patients in Group III died despite antibiotic therapy. Our data also show that US examination is sensitive in detecting Group II ABN lesions (62% positive rate), and revealed marked renal enlargement in most Group III lesions (89%). It is therefore a useful initial imaging modality in providing information vital to clinical decision making. CONCLUSION Our experiences suggest that renal bacterial infection may show the continuum of severity from uncomplicated APN to ABN, demonstrated on postcontrast CT scan as wedge-shaped lesions to mass-like lesions, and possibly, finally to frank abscess formation. We classify ABN into three subgroups according to CT findings, and good correlation with clinical severity is demonstrated. These findings deliver valuable concepts regarding the pathophysiology and clinical management of this disease.
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Affiliation(s)
- J J Huang
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China
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59
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Chen KW, Tsai YL, Chen WS, Lien YR, Su WH, Lee CY, Hsieh CY. Binding and growth-stimulation of cervical cancer cell lines by prolactin. J Formos Med Assoc 1992; 91:804-7. [PMID: 1362121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
Two cervical cancer cell lines CC7-T and Si-Ha were employed to observe the relationship between cervical cancer and prolactin. By immunocytochemical and indirect immunofluorescent assays using two prolactin monoclonal antibodies PRL-149 and PRL-151, both cell lines with added prolactin (10 ng/mL) were noted to be positive for PRL-151, but negative for PRL-149. The control cell lines from ovarian cancer and the myeloma lines were both stained negative. By using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, it was noted that CC7-T and Si-Ha grew better in the presence of various added concentrations of prolactin, ranging from 0.1 to 1,000 ng/mL, suggesting that prolactin may enhance the growth of cervical cancer. The degree of stimulation appears to depend on cell differentiation. However, prolactin levels in the cultured supernatant were undetectable by the enzyme immunoassay (EIA) method. We postulate that prolactin can bind and stimulate the growth of some cervical cancer cell lines, probably through the prolactin receptor rather than by autocrine regulation.
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Affiliation(s)
- K W Chen
- Department of Obstetrics and Gynecology, Provincial Tao-Yuan General Hospital, Taiwan, R.O.C
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60
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Lee CY, Chen KW, Sheu FS, Tsang A, Chao KC, Ng HT. Studies of a tumor-associated antigen, COX-1, recognized by a monoclonal antibody. Cancer Immunol Immunother 1992; 35:19-26. [PMID: 1611619 PMCID: PMC11038318 DOI: 10.1007/bf01741050] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/1991] [Accepted: 11/21/1991] [Indexed: 12/27/2022]
Abstract
Monoclonal antibodies against an ovarian tumor cell line, OC-3-VGH, were generated using modified hybridoma technology. Among the seven that were selected for their high specificity and affinity to ovarian cancer cells and low cross-reactivity to most normal human tissues, RP 215 was shown to react specifically with a tumor-associated antigen, COX-1, from certain ovarian/cervical cancer cell lines. By Western blot assay, COX-1 was shown to have a subunit molecular mass of about 60 kDa and exist as an aggregate in the native state. COX-1 could also be detected in the shed medium of certain cultured tumor cells. A solid-phase sandwich enzyme-immunoassay procedure was designed for quantitative determinations of COX-1 in the shed medium or in patients' sera using RP 215 for both well-coating and the signal detection. Highly purified COX-1 was obtained from the shed medium of cultured OC-3-VGH tumor cells mainly by hydroxyapatite and immunoaffinity chromatography with RP 215 as the affinity ligand. At neutral pH, purified COX-1 also exists as an aggregate and is relatively stable at temperatures below 50 degrees C. Its immunoactivity was found to decrease with time in the presence of trypsin. However, the immunoactivity of COX-1 was not affected upon incubation with carbohydrate-digestive enzymes or concanavalin A and only partially inactivated in the presence of NaIO4 or iodoacetamide. Treatments of COX-1 with dithiothreitol and guanidine thiocyanate resulted in a complete loss of activity. Furthermore, rabbit antisera raised against purified COX-1 exhibited similar immunospecificity to that of RP 215. The results of this study suggest that COX-1 is a glycoprotein consisting of a 60 kDa subunit, which is recognized by RP 215 through its peptide determinant. Preliminary retrospective clinical studies were performed to assess the utility of a COX-1 enzyme immunoassay kit for detection and monitoring of patients with ovarian and cervical cancers.
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Affiliation(s)
- C Y Lee
- Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, Canada
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61
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Chen KW, Huang SC, Yu DC. The effects of measurement errors in the plasma radioactivity curve on parameter estimation in positron emission tomography. Phys Med Biol 1991; 36:1183-200. [PMID: 1946602 DOI: 10.1088/0031-9155/36/9/003] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of three error sources in plasma curve measurements on parameter estimation in kinetic analysis of positron emission tomography (PET) fluorodeoxyglucose (FDG) data are investigated by computer simulation. The three error sources are: (1) measurement noise in the radioactivity concentrations of plasma samples; (2) linear interpolation between adjacent plasma sampling points of the plasma time activity curve; and (3) incorrect weights used for the least-squares regression. All three error sources are found to increase the variability of the parameter estimates, with the first one a primary error source in normal PET FDG studies. The performance of five estimation methods which account for the error sources are evaluated. When the noise variances of the plasma and the tissue measurements are not known, an iterative weighting procedure is shown to give accurate and reliable estimates.
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Affiliation(s)
- K W Chen
- Division of Nuclear Medicine and Biophysics, UCLA School of Medicine, University of California, Los Angeles 90024
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62
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Abstract
Emphysematous pyelonephritis is a severe necrotizing infection that usually occurs in patients with diabetes mellitus or obstructive uropathy. Although glucose fermentation has been considered as the main cause of gas production the actual mechanism remains controversial. Compositions of gas samples from 2 patients with emphysematous pyelonephritis recently encountered were analyzed, and showed 15% hydrogen, 4.8% carbon dioxide, 60% nitrogen, 6.7% oxygen and some unknown gases in case 1, and 3.4% hydrogen, 22% carbon dioxide, 66% nitrogen and 9.8% oxygen in case 2. These results tend to implicate mixed acid fermentation of glucose as the pathway by which emphysematous urinary tract infections develop.
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Affiliation(s)
- J J Huang
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China
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63
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Kuo CY, Chen KW, Fu J, Lam KW, Lee CY. Generation of monoclonal antibodies to prostatic acid phosphatase isoenzyme 2 and application in solid-phase enzyme immunoassay. Biotechnol Appl Biochem 1989; 11:89-95. [PMID: 2650706 DOI: 10.1111/j.1470-8744.1989.tb00052.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Monoclonal antibodies specific to prostatic acid phosphatase (PAP) isoenzyme 2 were generated by using an improved hybridoma technique. After three subcutaneous immunizations and three intravenous boosters, cell fusion experiments were performed. The hybrid cells were first cultured in a semisolid medium containing methylcellulose and later transferred to a liquid medium for further subculture. Out of a total of 600 colonies recovered after two cell fusion experiments, 13 were shown to exhibit affinity to PAP isoenzyme 2 by radioimmunoassay. Nine hybrid cell lines which showed high affinity and specificity were established for further evaluation. Their immunoglobulin subclass was determined to be immunoglobulin G. The association constants between PAP isoenzyme 2 and each monoclonal antibody were determined by titration curve in radioimmunoassay (RIA). Three of them (PAP 1, PAP 03, and PAP 019) were shown to be over 1 X 10(9) M-1. From the results of a matrix cross-matching procedure, a pair of antibodies (PAP 03 and PAP 1) reacting with discrete antigenic determinants were identified for preparing a solid phase sandwich enzyme immunoassay (EIA) kit. The designed EIA procedure could be performed within 40 min in a one-stage incubation protocol. The assay time was shorter than that of other commercial RIA or EIA kits, and the sensitivity was 0.4 ng/ml which was comparable to that of RIA kits. The EIA kit was shown not to cross-react with human thyroid stimulating hormone, alpha-fetoprotein, carcinoembryonic antigen, and acid phosphatases derived from tissues other than prostate. Therefore, this design was a simple and rapid method with high sensitivity and specificity for determining PAP isoenzyme 2 in human serum.
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Affiliation(s)
- C Y Kuo
- Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada
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64
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Abstract
Monoclonal antibodies against human follicle-stimulating hormone (hFSH) were generated by using an improved hybridoma technique with a semisolid medium in methylcellulose for initial cloning. The generated monoclonal antibodies were characterized with respect to their subunit and epitope specificity as well as cross-reactivity to other glycoprotein hormones. Monoclonal antibodies of high affinity and high specificity to hFSH were finally selected for applications in sandwich enzyme immunoassay. The monoclonal antibody specific to the alpha-subunit of FSH was coated on microtiter wells and served as the first antibody. The other high-affinity monoclonal antibody specific to beta-subunit of FSH was labeled with horseradish peroxidase and served as the second antibody. This immunoassay can be performed within 70 min at room temperature and has a minimum sensitivity of 2 mIU/ml for serum sample.
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Affiliation(s)
- K W Chen
- Andrology Laboratory, University of British Columbia, Vancouver, Canada
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65
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Chow SN, Chen KW, Su SL, Tung J, Lee CY. Generation and epitope analysis of thyroid stimulating hormone-specific monoclonal antibodies for enzyme immunoassays. Biotechnol Appl Biochem 1988; 10:137-42. [PMID: 2454641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
By using an improved hybridoma technique with a semisolid medium of methylcellulose for initial cloning, numerous high affinity monoclonal antibodies against human thyroid stimulating hormone (TSH) were generated. These antibodies were characterized with respect to their subunit and epitope specificity. Epitope analysis of antibodies specific to the beta-subunit of TSH was performed by a sandwich pairing procedure. Based on the results of this analysis, it was concluded that there are four distinct TSH-specific epitopes on the beta-subunit of TSH; these are designated a, b, c, and ab. The five antibodies binding to epitopes a, b, and c are not mutually exclusive. However, the antibody binding to epitope ab prevents further binding of other antibodies to epitope a or b, but not to epitope c. This epitope analysis enabled us to combine three high affinity monoclonal antibodies, each of which reacts with epitopes a, b, and c, respectively, in a typical sandwich enzyme immunoassay. One was immobilized on polystyrene beads and the other two were conjugated with horseradish peroxidase and served as the second antibodies. This enzyme immunoassay can be performed within 90 min and with a minimum sensitivity of 0.2-0.3 microIU/ml.
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Affiliation(s)
- S N Chow
- Department of Obstetrics and Gynaecology, National Taiwan University Hospital, Taipei, Republic of China
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