Enhanced Chemiluminescence Immunoassay Research Articles

Novel highly sensitive chemiluminescence immunoassay for quantitation of durvalumab using a signal enhanced horseradish peroxidase-luminol-hydrogen peroxide reaction for detection system

Durvalumab (DUR) is a human monoclonal antibody used for the immunotherapy of lung cancer. It is a novel immune-checkpoint inhibitor, which blocks the programmed death 1 (PD-1) and programmed death-ligand 1 (PD-L1) proteins and works to promote the normal immune responses that attack tumor cells. To support the pharmacokinetic (PK) studies, therapeutic drug monitoring (TDM) and refining the safety profile of DUR, an efficient assay is required, preferably immunoassay. This study describes, for the first time, the development and validation of a novel enhanced chemiluminescence immunoassay (CLIA) with high sensitivity and selectivity for the quantitation of DUR in plasma samples. The assay protocol was conducted in 96-microwell plates and involved the non-competitive binding reaction of DUR to its specific antigen (PD-L1 protein). The immune complex of DUR with PD-L1 formed on the inner surface of the assay plate wells was quantified by a chemiluminescence (CL)-producing horse radish peroxidase (HRP) reaction. The reaction employed 4-(1,2,4-triazol-1-yl)phenol (TRP) as an efficient enhancer of the HRP-luminol–hydrogen peroxide (H2O2) CL reaction. The optimum protocol of the proposed CLIA was established, and its validation parameters were assessed as per the guidelines for the validation of immunoassays for bioanalysis. The working dynamic range of the assay was 10–800 pg mL–1 with a limit of detection (LOD) of 10.3 pg mL–1. The assay enables the accurate and precise quantitation of DUR in human plasma at a concentration as low as 30.8 pg mL–1. The CLIA protocol is simple and convenient; an analyst can analyze several hundreds of samples per working day. This high throughput property enables the processing of many samples in clinical settings. The proposed CLIA has a significant benefit in the quantitation of DUR in clinical settings for assessment of its PK, TDM and refining the safety profile.

Clinical value of serum and tissue AGR2 for diagnosis and prognosis in epithelial ovarian cancer.

Purpose: To clarify the value of AGR2 for diagnosis and prognosis in epithelial ovarian cancer (EOC). Methods: Serum AGR2 from 203 subjects were detected by ELISA, while CA125 and HE4 were determined by enhanced chemiluminescence immunoassay. The diagnostic efficacy was assessed using receiver operating characteristic curves. Tissue microarray was employed to compare tissue AGR2. Results: Combined detection of AGR2, CA125 and HE4 improved the diagnostic specificity in the discrimination of EOC from healthy controls. Serum AGR2 was significantly higher, while CA125 and HE4 were significantly lower in EOC patients post-operatively. Low AGR2 expression may predict poorer prognosis. Conclusion: Incorporation of AGR2 improved the specificity of CA125 and HE4 in EOC diagnosis, and may act as a tumor suppressor whose low expression in EOC patients predicted poorer outcomes.

Reverse algorithm for screening of syphilis and trends in prevalence among blood donors in Coastal Karnataka.

Transfusion transmissible syphilis is caused by Treponema pallidum; blood donors are traditionally screened with non-treponemal antibody tests to ensure transfusion safety. Detection of specific antibodies against T. pallidum is employed in reverse algorithm screening. We aim to analyze the utility of the reverse algorithm screening strategy for T. pallidum and to determine the prevalence trends among blood donors in our centre. The study was conducted in a Transfusion Centre catering to the 2030 bedded Tertiary Care Centre in coastal Karnataka in two timelines from 2012 to 2014, and 2019 to 2020, respectively. A fully automated Enzyme-Linked Immunosorbent Assay and Enhanced Chemiluminescence Immunoassay, which detect both IgM and IgG antibodies against T.pallidum were used in the study. Blood donor data from 2008 to 2020 were also analyzed to observe the trend in prevalence rate of syphilis among blood donors. Among 26329 and 388 blood donors screened with ELISA and ECI, 134 (0.51%) and 9 (2.3%) were reactive to T. pallidum antibodies respectively. TPHA confirmed that 104 and 9 donors were reactive from each of the ELISA and ECI reactive donor groups. The increase in the prevalence of syphilis was observed with the use of reverse algorithm compared to the traditional strategy. The prevalence of syphilis in the present study ranged from 0.02 to 0.28%. The reverse algorithm screening can give a better result with a positive predictive value of 77.61% and 88.9% for ELISA and ECI. respectively Our study found that the use of reverse algorithm might increase the blood discard rate slightly but adds on to safety of blood components.

Effects of Short-term and Long-termUse of Lithium on Thyroid Hormones in Nepalese Patients with Bipolar Disorder

Background: Lithium has been used for decades as mood-stabilizing agents in the management of bipolar disorder and other condition with a manic component. However, some studies have also reported varying degrees of thyroid abnormalities associated with lithium therapy and effect of such therapy on thyroid function is unclear in this part of world. Therefore, we aimed to determine the effect of long term use of lithium on thyroidfunctionin the individual with bipolar disorder receiving lithium therapy.
 Methods: A total of 75 bipolar disorder patients (24 males, 51 females) who are under lithium therapy and equal number of control were recruited for this study. Diagnosis of bipolar disorder was made by psychiatrist according to ICD-10-DCR guidelines and DSM-IV criteria. Serum fT3, fT4 and TSH were measured by enhanced chemiluminescence immunoassay. Statistical analysis was performed using SPSS 20.0 version.
 Results: The prevalence of primary hypothyroidism and subclinical hypothyroidism were found significantly increased in lithium treated group (12% and 17%, respectively) which was further increased with duration of treatment. The mean fT3 and fT4 concentration is low in lithium treated group compared to control group.Butmean TSH level was found significantlyhigher in lithium treated group compared to control (9.67±12.47 vs. 3.41±3.69, p<0.005).
 Conclusion: Our findings indicate that use of lithium therapy is associated with higher degree of primary hypothyroidism and subclinical hypothyroidism and female are more susceptible for the thyroid dysfunction associated with lithium therapy.

HUBUNGAN ASUPAN BESI HEME DAN NON-HEME KADAR FERRITIN PADA CALON PENGANTIN PEREMPUAN DI KOTA PADANG

Women of childbearing age are prone to anemia, especially iron-deficiency anemia. The outcome might be seen in the high maternal mortality rate in the Padang city (16 cases. Serum ferritin can be used as an initial indicator to determine iron deficiency. A decrease in serum ferritin levels can be influenced by iron intake. This study aimed to determine the relationship between heme and non-heme iron intake with ferritin serum concentration in women’s bride candidates in Padang City. This analytical study with a cross-sectional design involved 30 bride candidates, 20-30 years old. Iron intake were collected using the Semi-Quantitative Food Frequency Questionnaire (SQ-FFQ), and serum ferritin levels were measured using the Enhanced ChemiLuminescence Immuno Assay (ECLIA) method. Data were analyzed using the Pearson correlation coefficient test. The results showed the mean of heme and non-heme iron intake was 2.76 ± 0.90 mg/day and 3.83 ± 0.97 mg/day, respectively, and the mean of serum ferritin levels was 46.27 ± 27.61 ng/ml. The test showed no significant correlation between heme (r=0.094, p=0.622) and non-heme iron (r=-0.179, p=0.345) intake with serum ferritin levels. This study concludes that there is no relationship between heme and non-heme iron intake with serum ferritin levels on bride candidates in Padang City. Therefore, to prevent the incidence of anemia during pregnancy, it is highly recommended for the brides to increase their iron intake from both animal and vegetable sources.

Head-to-head comparison of Enzyme Linked Immunosorbent Assay (ELISA) and Enhanced Chemiluminescence Immunoassay (ECLIA) for the detection of Transfusion Transmitted Disease (TTD) Markers; HIV, HCV and HBV in blood donors, in India

Safe blood transfusion being the cornerstone of any Blood Transfusion Services requires meticulous testing for Transfusion Transmitted Disease (TTD) markers in donated blood. We performed head-to-head comparison of ELISA and ECLIA for detection of TTD markers for Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV) and Hepatitis B Virus (HBV) in 10,164 Indian blood donors. All concordant reactive, discordant reactive and concordant non-reactive samples were re-confirmed using Individual Donor-Nucleic Acid Amplification Test (ID-NAT) as the ‘gold standard’ test. 223 samples were found reactive; out of which 93 (four HIV, 34 HCV and 55 HBV) samples were concordant reactive and tested positive by both methods while 130 discordant reactive samples were reactive either by ELISA or ECLIA. Out of 130 discordant reactive samples ELISA-reactive and ECLIA-non-reactive samples for HIV, HCV and HBV were 15, eight, and 29 respectively while ECLIA-reactive ELISA-non-reactive samples for HIV, HCV and HBV were 39, 36 and three respectively. Sensitivity of ECLIA and ELISA was 100 % for all three TTD markers, while specificity was 99.62 % and 99.85 % for HIV; 99.64 % and 99.84 % for HCV and 99.97 % and 99.70 % for HBV respectively. Strength of agreement and Kappa Statistics for ECLIA and ELISA compared to the gold standard test was poor and fair for HIV (k = 0.169 and 0.347), moderate and good for HCV (k = 0.539 and 0.763), and very good and good for HBV (k = 0.973 and 0.783). According to this study, it can be concluded both the testing techniques; ELISA and ECLIA have 100 % sensitivity for the detection for HBV, HCV and HIV in blood donors and therefore, either can be used for TTD screening in blood banks in India.

The clinical value of the combined detection of sEGFR, CA125 and HE4 for epithelial ovarian cancer diagnosis.

This study aims to investigate the clinical value of combined detection of serum soluble epidermal growth factor receptor (sEGFR), cancer antigen 125 (CA125), and human epididymis protein 4 (HE4) in the diagnosis of epithelial ovarian cancer (EOC). From December 2017 to October 2018, the serum samples were obtained from the Affiliated Hospital of Xuzhou Medical University, with 30 patients as EOC group, 30 patients with benign ovarian neoplasms as benign group, and 17 healthy subjects as healthy group. Besides, among 30 EOC patients, 9 serum samples were obtained from pre-operative and post-operative EOC patients. The levels of serum sEGFR were detected by enzyme-linked immunosorbent assay (ELISA), while CA125 and HE4 were detected by enhanced chemiluminescence immunoassay (ECLIA). The diagnostic value was evaluated by receiver operating characteristic (ROC) curve analysis. The levels of serum sEGFR, CA125, and HE4 in EOC group were significantly higher than those in benign group (p<0.05) and healthy group (p<0.05). When using a single tumor marker, the CA125 shows the highest sensitivity (93.30%) and HE4 shows the highest specificity (97.87%). The specificity of combined detection of serum sEGFR, CA125, and HE4 was 100%, which was significantly higher than that using a single tumor marker. The area under the ROC curve (AUC) of combined detection of serum sEGFR, CA125, and HE4 (0.965) was much higher than that of the single detection and higher than that of combined detection of CA125 and HE4 (0.940). Moreover, the level of serum sEGFR in post-operative EOC group was significantly lower than that in the corresponding pre-operative EOC group (p<0.05). Our study shows that combined detection of serum sEGFR, CA125, and HE4 increases the specificity and efficiency in EOC diagnosis, indicating that sEGFR could be a potential biomarker for the diagnosis and prognosis of EOC.

A study of thyroid profile in depression

A study of thyroid profile in depression - IJCBR- Print ISSN No: - 2394-6369 Online ISSN No:- 2394-6377 Article DOI No:- 10.18231/j.ijcbr.2019.064, International Journal of Clinical Biochemistry and Research-Int J Clin Biochem Res

Visualization of Latent Fingermarks by Enhanced Chemiluminescence Immunoassay and Pattern Recognition.

Herein we report the combination of enzyme-linked immunoassay and pattern recognition analysis for extracting both chemical and spatial information from latent fingermarks (LFMs). The development approach basically involves two steps, namely, specific recognition of protein and polypeptide secretions present in the ridge residues of LFMs by horseradish peroxidase (HRP)-labeled antibodies and the HRP-catalyzed chemiluminescent (CL) reaction between luminol and H2O2. The emitted light can spatially resolve the ridges, generating a bright image against the dark object surface for visualization of an LFM. Meanwhile, thanks to the molecular specificity of the immunoassay step, the emission also provides us additional information on the existence of specific substances in LFMs. The developed LFMs are further processed by a set of digital image processing procedures. Quantitative analysis based on minutia features shows that even poorly developed fingermarks can be matched successfully. This work offers the promise of facilitating cross-disciplinary studies between data-processing approaches and fingermark development techniques, such as the extraction of more information from LFM evidence, as well as the establishment of evaluation criteria for an enhancement technique.

Insignificant Correlation between Thyroid Hormone and Antithyroid Peroxidase Antibodies in Alopecia Areata Patients in Northern Rajasthan.

Background:Alopecia areata (AA) is a common, recurrent form of nonscarring alopecia which often presents as circumscribed patches of spontaneous hair loss. The global prevalence of this disease varies from 0.1% to 0.2% in general population and 7–30 cases per 1000 dermatological patients. The etiology of AA still remains uncertain; however, genetic or environmental factor and autoimmunity are claimed responsible for it. Various autoimmune diseases, such as Hashimoto's thyroiditis, diabetes mellitus, vitiligo, and lupus erythematosus, have been reported in association with AA.Aim:The index study was aimed at estimation of serum T3, T4, thyroid-stimulating hormone, and antithyroid peroxidase (TPO) antibodies.Material and Methods:Similar age/sex-matched AA patients and controls (110 in each group). Enhanced chemiluminescence immunoassay for thyroid profile and anti-TPO antibody level estimation in veinous blood sample.Observations:The mean/standard deviation (SD) of T3 was 3.30 ± 0.84 pg/ml in AA while 3.27 ± 0.67 pg/ml in controls (P = 0.302). Serum mean/SD of T4 level was1.23 ± 0.76 ng/dl in AA patients while 1.17 ± 0.34 ng/dl in controls (P = 0.522). The mean/SD of anti-TPO levels in AA patients was 21.52 ± 35.09 while 56.43 ± 140.72 in controls (P = 0.136).Limitation:The limitation of this study was moderate number of AA patients and different genotype of study population.Conclusion:Occurrence of thyroid dysfunction and evidence of anti-TPO antibodies in AA is rare event in this study population.

Tacrolimus decreases insulin sensitivity without reducing fasting insulin concentration: a 2-year follow-up study in kidney transplant recipients

New Onset Diabetes after Transplantation (NODAT) is defined as sustained hyperglycemia developing in patients without diabetes history before transplantation. A cohort study was performed to access the effects of tacrolimus on insulin secretion and insulin sensitivity and consequently in the development of NODAT in kidney transplant recipients. Then, we further investigated the association between NODAT and single-nucleotide polymorphisms of IRS-1 and IRS-2 in renal allograft recipients. One hundred and fifty-eight kidney transplant patients, receiving tacrolimus as the base immunosuppressant, were divided into two groups: with or without NODAT. Plasma levels of fasting insulin concentration (FINS) and C-peptide were determined by enhanced chemiluminescence immunoassay and ADVIA Centaur C peptide assay, respectively. The genotypes of Gly1057Asp in IRS-2 and Gly972Arg in IRS-1 were detected through polymerase chain reaction fragment length polymorphism in NODAT and non-NODAT patients. It was found that the concentrations of fasting plasma insulin and C-peptide in NODAT and non-NODAT patients treated with tacrolimus were higher than that in healthy volunteers (p < 0.05). Fasting plasma insulin concentration in NODAT was significantly elevated compared with than that in non-NODAT group (p < 0.05). But there are no statistical differences in fasting plasma C-peptide concentrations between NODAT and non-NODAT groups. The allele and genotype frequencies of IRS-2 Gly1057Asp and IRS-1 Gly972Arg in NODAT patients were not significantly different from non-NODAT patients (p > 0.05). In conclusion, insulin resistance is the primary cause of tacrolimus-induced NODAT. The IRS-2 Gly1057Asp and IRS-1 Gly972Arg genotypes are not related to NODAT.

Association of low 25-hydroxyvitamin D levels with the frailty syndrome in an aged population: results from the KORA-age Augsburg study.

Older adults often suffer from vitamin D deficiency and from the frailty syndrome charac-terized by different physical limitations, complicating independent everyday life. Previous studies have suggested a relationship between vitamin D status and the frailty syndrome, but results have been partly inconsistent, particularly regarding the shape of the association. Therefore, our aim was to further assess the association of 25-hydroxyvitamin D (25(OH)D) serum levels and frailty in older participants. Cross-sectional population-based study. The study population included 478 men and 462 women of the KORA (COoperative health research in the Region of Augsburg)-Age study born before 1944 examined in 2009. Classification of participants into different frailty states was performed according to the following criteria: weight loss, exhaustion, physical inactivity, slowness, and weakness. PARTICIPANTS who met 1-2 or ≥ 3 of the 5 criteria were classified as prefrail or frail, respectively. Total 25(OH)D was measured in non-fasting serum samples with an enhanced chemiluminescence immunoassay. Sequential logistic regression models adjusted for age, sex, season, lifestyle factors, diseases and biomarkers including parathyroid hormone (PTH) were calculated. High levels of 25(OH)D were inversely associated with being prefrail (N=351) or frail (N=38) in the model adjusted for age, sex, season and lifestyle factors. Compared to levels <15 ng/ml, odds ratios (ORs) (95% confidence intervals (CIs) were 0.52 (0.34-0.78) for levels of 15-<20 ng/ml, 0.55 (0.37-0.81) for levels of 20-<30 ng/ml and 0.32 (0.21-0.51) for levels ≥ 30 ng/ml. Additional adjustment for potential mediators including PTH only slightly attenuated these associations. For single frailty-components, significantly decreased ORs were found for exhaustion, physical inactivity and slowness comparing 25(OH)D levels ≥ 30 ng/ml with levels <15 ng/ml. Subjects with 25(OH)D serum levels ≥ 15 ng/ml were less frequently prefrail or frail.

Abstract 4704: Correlation between serum cytokine/angiogenic factors (CAFs) and tumor markers in testicular germ cell tumor patients.

Abstract Background: There is an unmet need for noninvasive markers to identify patients with TGCTs most likely to benefit from treatment and to measure the effects of therapies. Cytokines can be easily identified and they have an important role on tumor initiation, growth, and progression. Prognostic and predictive values of 52 plasma CAFs in patients with metastatic renal cell carcinoma were recently investigated. Our endpoint was to find out relationship between established tumor markers beta-human choriogonadrotropin (HCG) and alphafetoprotein (AFP) with CAFs. Methods: We enrolled 47 patients with TGCTs treated by 1st line platinum based systemic chemotherapy. All patients received G-CSF support after chemotherapy (44 patients pegfilgrastim, 3 patients filgrastim). Fifty one plasma CAFs were analyzed before the 1st (47 patients) and before the 2nd cycle of chemotherapy (22 patients) using multiplex bead arrays (Human Group I and II cytokine panels and TGF beta by Bio-Plex 200 system, Bio-Rad Laboratories, Hercules, CA). HCG and AFP were measured by enhanced chemiluminescence immunoassay. CAFs were correlated to pretreatment serum levels of HCG and AFP. Spearman's correlation test was used to analyze the relationship between CAFs and tumor markers. We considered p &amp;lt;0.05 to be significant. Results: Median pretreatment AFP and HCG were 2.6 U/ml (range 0.9-13936.0 U/ml) and 5.5 mIU/ml (range 0.0-564261.0 mIU/ml), respectively. By the correlation analyses 4 from 51 pretreatment plasma CAFs were negatively and one positively correlated to pretreatment AFP. Negatively correlated CAFs were TGF-b1 (p=0.041), TGF-b3 (p=0.040), IL-7 (p=0.039) and G-CSF (p=0.016), positive correlation between pretreatment MIF (p=0.005) and pretreatment values of AFP was observed. We investigated, that pretreatment HCG had positive correlation to IL-2Ra (p=0.031), MIG (p=0.015), SCGF-b (p=0.045) and b-NGF (p=0.017), there was no negative elevation of pretreatment CAFs in correlation with pretreatment HCG. Additionally, we calculated ratio between pretreatment and postreatment values of CAFs. We investigated, that pretreatment HCG positively correlated to ratio values of several CAFs (IL-2Ra, p=0.009; IL-16, p=0.046; IL-18, p=0.014; SCGF-b, p=0.018; CTACK, p=0.004) and pretreatment AFP to RANTES (p=0.035), no negative relationships were observed. Conclusions: Several serum CAFs with significant correlation to pretreatment AFP and HCG were identified in this study. We suppose that this finding may be useful for further investigations, biological and clinical consequences of this correlation have to be find out. This work was supported by the Slovak Research and Development Agency under the contract No. APVV-0016-11. Citation Format: Daniela Svetlovska, Michal Mego, Dana Cholujova, Paulina Gronesova, Patrik Palacka, Usakova Vanda, Vera Miskovska, Bibiana Vetrakova-Krakovska, Jan Luha, Jozef Mardiak. Correlation between serum cytokine/angiogenic factors (CAFs) and tumor markers in testicular germ cell tumor patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4704. doi:10.1158/1538-7445.AM2013-4704

Need for nucleic Acid testing in countries with high prevalence of transfusion-transmitted infections.

Introduction. In India, family/replacement donors still provide more than 45% of the collected blood. With increasing voluntary blood donation and the still-prevalent infectious diseases in donors, we need to augment transfusion-transmitted infections (TTIs) testing before use. Our study was aimed to know the seroprevalence of TTIs among the donors of Rajasthan and the need for newer technologies like nucleic acid testing (NAT). Materials and Methods. Enhanced chemiluminescence immunoassay (ECi) was used for detection of HBsAg, anti-HIV, and anti-HCV in donor serum. 50% of the blood units which were negative on ECi were randomly selected and subjected to NAT testing for HBV, HCV, and HIV. Results. The total seroprevalence of TTIs is 2.62%. Of the randomly selected donor units negative by ECi, 8 turned out to be reactive on NAT testing: 4 were voluntary and 4 were family/replacement donors. Combined NAT yield (NAT reactive/seronegative) for HIV, HCV, and HBV was 0.034% (1 in 2972 donations). All the 8 reactive samples were positive for HBV DNA. Conclusion. In countries with a high prevalence of TTIs like India there are likely to be a significant number of window period donations that can be identified by NAT which may be implemented in blood centers allover India with serological testing to provide safe blood and cost alone should not be a deterrent to the government and implementing agencies.

Ultrasensitive detection of porcine circovirus type 2 using gold(iii) enhanced chemiluminescence immunoassay

Porcine circovirus type 2 (PCV2) is associated with many diseases especially postweaning multisystemic wasting syndrome (PMWS), which has brought huge economic loss to the swine industry worldwide. Viral detection will pave the way for this disease prevention. Herein, we developed a facile, rapid and ultrasensitive method for detection of PCV2 based on gold(III) enhanced chemiluminescence immunoassay (CLIA). The gold(III), dissolved from the gold nanoparticle-monoclonal antibody conjugate, served as an analyte for the indirect measurement of PCV2. Under the optimal conditions, the detection limit for the detection of PCV2 was 1.71 x 10(3) copies mL(-1). Moreover, the CLIA signal can be further enhanced by using hydroxylamine-amplified gold nanoparticles, and the limit of detection was as low as 2.67 x 10(2) copies mL(-1). Compared with conventional polymerase chain reaction (PCR), the proposed method has good sensitivity and reliability in analysis of 36 serum samples, and showed great potential in virus assays.

Serum Concentration of Vitamin D and Parathyroid Hormone After Living Kidney Donation

Background Metabolic consequences resulting from loss of renal mass in living kidney donors remain uncertain. There is recent focus on the changes in the active form of vitamin D because it is an agent for cancer regulation. The objective of the study was to measure serum concentrations of 1,25-dihydroxycholecalciferol, parathyroid hormone and insulin-like growth factor-1 (IGF-1) in living donors after kidney donation. Patients and Methods Forty living kidney donors reported for follow-up visits. Their mean age was 46.14 years. They were women in 52.5% of cases. The mean observation period was 65.6 months. Serum 1,25(OH) 2D 3 and IGF-1 concentrations were measured by radioimmunoassay after extraction. Serum intact parathyroid hormone (PTH) was quantified using an enhanced chemiluminescence immunoassay system. Results 1,25-dihydroxycholecalciferol deficiency in 57.5% patients after nephrectomy was the most important change we noted. No correlation was observed between 1,25(OH) 2D 3 and PTH. A decreased serum IGF-1 concentration was observed in 17.5% of donors. However, decreases in both serum IGF-1 and 1,25(OH) 2D 3 concentrations were observed in 12.5% of donors. Conclusion Prospective studies may be essential to determine metabolic changes after nephrectomy among living kidney donors.

Evaluation of the ELISA and the enhanced chemiluminescence immunoassay in use to determine the serum markers for liver fibrosis

To evaluate the detection method of ELISA and Enhanced Chemiluminescence Immunoassay (ECLIA) in use to determine serum hyaluronate acid (HA), laminin (LN), type IV collagen (IV-C) and type III procollagen (PC III). 253 patients with chronic hepatitis B were determined the four liver fibrosis serum markers with both the ECLIA and ELISA, and then compared with pathology results separately. Both the detection results of ELISA and ECLIA can reflect that the patient's liver fibrosis from hepatitis to liver cirrhosis aggravated gradually. Compared with ELISA, the results of ECLIA and pathology have a better correlation. The detection of four liver fibrosis serum markers by ECLIA could indicate the better the response of the state of live fibrosis.

Gold(iii) enhanced chemiluminescence immunoassay for detection of antibody against ApxIV of Actinobacillus pleuropneumoniae

We report, for the first time, a chemiluminescence immunoassay (CLIA) method based on AuCl(4)(-)-enhanced luminol chemiluminescence (CL) reaction for the highly sensitive detection of ApxIV antibody of Actinobacillus pleuropneumoniae (APP). The AuCl(4)(-), which was the dissolution product of the gold nanoparticle-rabbit anti-pig IgG conjugate, served as an analyte in the CL reaction for the indirect measurement of antibody against ApxIV. The optimal condition of gold dissolution was composed of a 5.0 x 10(-2) M HCl, 1.5 x 10(-2) M NaCl, and 2.5 x 10(-4) M Br(2) solution. Under the optimal conditions, a good correlation between the relative CL photon counting and the dilution coefficient of serum was obtained in the dilution range of 1:160-1:40 000. Based on the analysis of clinical samples, the results indicated that CLIA had remarkable advantages in terms of reliability and practical use compared with indirect hemagglutination (IHA) and enzyme-linked immunosorbent assays (ELISA). The proposed method provided a new tool for the indirect determination of antibody against ApxIV in pig serum samples and showed great potential for numerous applications in immunoassays.

Laboratory evaluation of a fully automated chemiluminescence immunoassay for rapid detection of HBsAg, antibodies to HBsAg, and antibodies to hepatitis C virus.

The performance of a fully automated, random access, enhanced chemiluminescence immunoassay (Ortho/ECi) for the detection of antibody to hepatitis C virus (HCV) (anti-HCV), HBsAg, and antibody to HBsAg (anti-HBsAg), in human serum was compared to a Abbott second-generation enzyme immunoassay (EIA 2.0). The Ortho/ECi assays employ an immunometric technique with enhanced chemiluminescence for optimal assay performance. With regard to the study of clinical laboratory performance, six groups of sera prescreened with Abbott EIAs were assayed: anti-HCV-negative samples (n = 318), anti-HCV-positive samples (n = 177), anti-HBsAg-negative samples (n = 241), anti-HBsAg-positive samples (n = 239), HBsAg-positive samples (n = 158), and HBsAg-negative samples (n = 312). Sera with discrepant results in the two serological assays were resolved by confirmatory tests. Sera with indeterminate results by one or more confirmatory tests were evaluated by reviewing medical records. The overall concordance between the Ortho/ECi assay and the Abbott EIA were 97.78, 93.54, and 97.66% for anti-HCV antibodies, anti-HBsAg antibodies, and HBsAg, respectively. After resolving the discrepancies, the specificities of the new assay for anti-HCV and anti-HBsAg antibodies and HBsAg were 98.1, 92.8, and 100%, respectively. The sensitivities of the new assay for anti-HCV, anti-HBsAg, and HBsAg were 100, 98.8, and 97.4%, respectively. In conclusion, The Ortho/ECi assays for diagnosis of HCV and hepatitis B virus (HBV) infections are highly specific and sensitive assays. The rapid turnaround time, random access, full automation, and high throughput make it an effective assay system for clinical laboratory diagnosis of HCV and HBV infections.

Low free thyroxine concentrations and deficient nocturnal surge of thyroid-stimulating hormone in haemodialysed patients compared with undialysed patients.

There is little information on the differences in pituitary-thyroid function between undialysed and haemodialysed patients. Serum concentrations of free thyroxine (T(4)) and free triiodothyronine (T(3)), measured by enhanced chemiluminescence immunoassay, and thyroid-stimulating hormone (TSH) were compared in undialysed (n=22) and haemodialysed patients (n=85). The response of the serum TSH concentration to exogenously administered thyrotropin-releasing hormone (TRH) and circadian variation in serum TSH were also studied in the two groups. Serum free T(4) concentration was significantly lower in haemodialysed than in undialysed patients (1.02+/-0.02 vs 1.33+/-0.06 ng/dl, P<0.0001). Serum concentrations of free T(3) and TSH were essentially the same for the two groups. The response of serum TSH concentration to TRH was basically the same. Serum TSH concentration in undialysed patients during the night and in the morning were 142.4+/-15.4% and 121.7+/-4.1% of that during the day, the differences being significantly different. A nocturnal surge of TSH was not observed in haemodialysed patients. Low serum free T(4) concentration and a deficient nocturnal surge of TSH were found in haemodialysed patients compared with undialysed patients. The deficient nocturnal surge of TSH may contribute to the lower serum free T(4) concentration in haemodialysed patients.