Highly sensitive enzyme immunoassay of proinsulin immunoreactivity with use of two monoclonal antibodies

Kjems, Lise; Röder, Michael; Dinesen, Bo; Hartling, Svend G; Jørgensen, P. N.; Binder, Christian

doi:10.1093/clinchem/39.10.2146

Cited by 51 publications

(20 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Total serum proinsulin was measured using a two-site monoclonal ELISA technique. 22 After removal of proinsulin by PEG precipitation, C-peptide was determined by radioimmunoassay in duplicate, using antiserum M1221 (Novo Nordisk A/S, Copenhagen, Denmark). 23 Glycosylated haemoglobin (HbA 1C ) was analysed by a HPLC method.…”

Section: Study Design and Assay Methodsmentioning

confidence: 99%

Effect of pancreas transplantation and immunosuppression on proinsulin secretion

et al. 1998

View full text Add to dashboard Cite

Insulin resistance and increased demand for insulin secretion occur after successful pancreas transplantation. To investigate the potential effects of immunosuppression and pancreas transplantation on fasting beta-cell function, we studied fasting proinsulin and 32,33 split proinsulin secretion cross-sectionally and longitudinally in segmental pancreatic graft recipients (SPx, n = 18); in whole-pancreas graft recipients (WPx, n = 13); in nondiabetic kidney transplant recipients (Kx, n = 14) and in normal subjects (Ns, n = 14). Basal insulin secretion rates were significantly increased in SPx 15.8 (1.7), WPx 24.4 (4.5) and Kx 22.1 (2.1) vs Ns 9.7 (1.6) pmol min(-1) l(-1), p < 0.05, mean (SEM). Total proinsulin, intact proinsulin and 32,33 split proinsulin concentrations were significantly higher in all the transplanted groups than in normal subjects (p < 0.05), whereas the total proinsulin to C-peptide ratio and the 32,33 split proinsulin ratio were higher in SPx than in WPx, Kx and Ns (< 0.05). In the longitudinal study, beta-cell function in terms of proinsulin secretion remained stable for 1 year. In conclusion, fasting glucose homeostasis in pancreas-kidney transplant recipients is obtained at the expense of increased proinsulin secretion and increased insulin secretion rates, primarily induced by immunosuppression. In segmental pancreas graft recipients, increased fasting proinsulin and 32,33 split proinsulin relative to the number of beta-cells transplanted indicate more stress on the residual beta-cell and therefore higher secretory demand than in whole pancreas transplant recipients.

show abstract

Section: Study Design and Assay Methodsmentioning

confidence: 99%

Effect of pancreas transplantation and immunosuppression on proinsulin secretion

et al. 1998

View full text Add to dashboard Cite

show abstract

“…The detection limit was 5 pmol/L. The proinsulin level was measured in a similar manner by using another sensitive 2-site sandwich ELISA [21] . The detection limit in human sera was 0.25 pmol/L.…”

Section: Study Patientsmentioning

confidence: 99%

Association of human carboxypeptidase E exon5 gene polymorphisms with angiographical characteristics of coronary atherosclerosis in a Chinese population

Wang

Zhang

Yang

et al. 2008

Acta Pharmacologica Sinica

View full text Add to dashboard Cite

Aim: To explore the association between 801C>T and 847C>T polymorphisms of the human carboxypeptidase E (CPE) gene exon5, which could cause hyperproinsulinemia, and the angiographical characteristics of coronary atherosclerosis. Methods: In total, 1044 consecutive patients who underwent coronary angiography for suspected or known coronary atherosclerosis were examined with respect to their genotypes, insulin, proinsulin level, and other risk factors of coronary atherosclerosis. The angiographical characteristics of coronary atherosclerosis (ie the severity of coronary heart disease) were defined by Gensini's score (GS) system. Results: The results showed that the genotype frequencies of CC, CT, and TT at 801C>T locus were significantly different among the patients of the 4 groups who were classified by quartile values of GS (P=0.033). However, the frequency of the 847T allele was 0 for all the patients. The ordinal logistic regression analysis revealed that the increased risk of angiographical characteristics of coronary atherosclerosis were associated with CPE 801CT/TT variant genotypes [adjusted odds ratio (OR)=1.23, 95% confidence interval (CI) =0.93‐1.63 for 801CT and adjusted OR=3.13, 95% CI=1.18–8.28 for 801TT] compared with the 801CC wild‐type homozygotes. A stratification analysis showed that the effects of the CPE 801TT genotype were more evident among subgroups with relatively older (>=60 years) patients, males, and smokers. Furthermore, an analysis of covariance controlling age, sex, and body mass index indicated that differences of blood glucose, insulin, insulin resistance, and the proinsulin level between 801C>T genotype groups were not statistically significant. Conclusion: These findings indicate that the 801C>T polymorphism in the CPE exon5 gene may contribute to the angiographical characteristics of coronary atherosclerosis in the Chinese population.

show abstract

“…It appears, however, that the absolute levels of serum proinsulin were increased in the two patients when compared to the controls (ME, 45 pmol IF'; KS, 95 pmol I-'; control group, 3.6 f 0.3 pmol I-') and to values from 38 fasting healthy subjects (median 4.0pmol I-'. range 2.1-12.6pmol I-') published in the original proinsulin assay study (29). Calculating the fasting proinsulin/insulin ratio, a severe increase was found in patient KS (0.63) compared to that of patient ME (0.16) and the controls (0.16 f 0.07).…”

Section: Characterization Of Subjectsmentioning

confidence: 92%

“…The immunoassay is specific, and no proinsulin or 32-33 or desoxy-31-32 proinsulin splits are detected by the assay. Serum Cpeptide and serum proinsulin were analysed by radioimmunoassay (RIA) and ELISA techniques, respectively (27)(28)(29). H b AI, was measured by a highperformance liquid chromatography method (normal range 4.1-6.4%).…”

Section: Other Analytical Proceduresmentioning

confidence: 99%

Studies of insulin resistance in congenital generalized lipodystrophy*

Søvik¹,

Vestergaard²,

Trygstad

et al. 1996

Acta Paediatrica

View full text Add to dashboard Cite

Two well‐characterized patients with congenital, generalized lipodystrophy have been studied by the euglycaemic hyperinsulinaemic clamp technique in combination with indirect calorimetry. Furthermore, glycogen synthase in muscle biopsies was studied in one patient with regard to enzyme activity, immunoreactive protein and mRN A levels. The patients had fasting hyperinsulinaemia, and the rate of total glucose disposal was severely impaired, primarily due to a decreased non‐oxidative glucose metabolism. In the patient studied with muscle biopsy, the expected activation of glycogen synthase by insulin did not occur. In both patients there was severely increased hepatic glucose output in the basal state, suggesting a failure of insulin to suppress hepatic gluconeogenesis. During insulin infusion a substantially elevated rate of lipid oxidation remained in the patients, in contrast to the almost completely suppressed lipid oxidation in the controls. It is concluded that patients with congenital generalized lipodystrophy may present severe insulin resistance with regard to hepatic glucose production as well as muscle glycogen synthesis and lipid oxidation. The results suggest a postreceptor defect in the action of insulin in congenital generalized lipodystrophy. The further localization of such a defect is hampered by the still incomplete understanding of the pathways that link insulin‐stimulated tyrosine phosphorylation to the ultimate action of insulin upon target cells.

show abstract

Highly sensitive enzyme immunoassay of proinsulin immunoreactivity with use of two monoclonal antibodies

Cited by 51 publications

References 0 publications

Effect of pancreas transplantation and immunosuppression on proinsulin secretion

Effect of pancreas transplantation and immunosuppression on proinsulin secretion

Association of human carboxypeptidase E exon5 gene polymorphisms with angiographical characteristics of coronary atherosclerosis in a Chinese population

Studies of insulin resistance in congenital generalized lipodystrophy*

Contact Info

Product

Resources

About