Quantitation of whole molecule human chorionic gonadotropin and free beta-human chorionic gonadotropin subunit in the Abbott IMx analyser.

An assay for the quantitation of the serum levels of free and whole molecule-associated beta-subunit of human chorionic gonadotropin on the Abbott IMx analyzer is described. The assay detects human beta-chorionic gonadotropin with a sensitivity of approximately 0.5 IU/l while showing no cross-reactivity with follitropin (1000 IU/l) or thyrotropin (2.0 IU/l), and 0.02% cross-reactivity with lutropin (1000 IU/l). Haemoglobin (7.50 milligrams), bilirubin (0.50 milligrams), and triacylglycerols (10.6 milligrams) did not interfere with the assay. Pooled within-run, between-run, and total assay CVs were less than or equal to 5.2%, and less than or equal to 2.7%, and less than or equal to 6.3%, respectively. Values obtained with this assay correlated well (r = 0.98, n = 228) with those values obtained using the Hybritech TandemR-R HCG (Total Beta-HCG) IRMA. The normal range of the assay was found to be less than or equal to 5 IU/l (n = 311). The assay protocol provides results for up to 23 serum samples in approximately 47.5 minutes with the ability to report the human beta-chorionic gonadotropin concentrations of 5 specimens in approximately 15.5 minutes. We conclude that this is an acceptable assay for monitoring human beta-chorionic gonadotropin levels associated with normal pregnancy, reproductive pathology, and reproductive technology such as in vitro fertilization or embryo transfer.     

Monoclonal antibodies to non-assembled alpha and beta chain of human chorionic gonadotropin (hCG)]

Using a panel of monoclonal antibodies (MCA) to human chorionic gonadotropin (hCG) and its alpha and beta subunits and additional MCA to the non-assembled, free alpha and beta chains which were produced in the course of the present experiments, it was possible to extend the previously established epitope map of hCG. Two MCAs turned out to be specific for the free alpha chain of the glycoprotein hormones (GPH) and, thus, did not react with holo hCG. Two other MCA recognized two epitopes (beta 6 and beta 7) on the free form of the hCG beta only. Again, no holo hormone cross-reaction was observed. Whereas previously only nine antigenic hCG determinants (3 alpha, 4 beta, 2c) had been demonstrated, it was now possible to distinguish fourteen epitopes (5 alpha, 5 beta, 4c). In addition, epitope maps were established for the non-assembled, free subunits of hCG. These comprise six epitopes on the alpha chain (alpha 1- alpha 6) and seven on the beta chain (beta 1- beta 7). Both so far generally accepted premises of Judith Vaitukaitis, claiming the beta chain of the GPH to be immunologically species-specific, the beta chain to be immunologically hormone-specific, were clearly disproven by demonstrating inter- and intra-species cross-reaction of some MCA. Based on the immunological topography of the holo hCG molecule and its free subunits, highly specific and sensitive immuno-enzymometric assays (IEMA) with predictable specificities were designed, measuring either non-assembled subunits alone or in combination with the intact hormones.     

Monoclonal antibodies based sandwich erythro-immunoassay and 'dot' enzyme immunoassay for human chorionic gonadotropin in urine

Two simple solid-phase sandwich immunoassays for human chorionic gonadotropin (hCG) employing monoclonal antibodies have been described. One is a sandwich erythro-immunoassay employing V-shaped well microtitration plates coated with monoclonal anti-beta-hCG antibody and monoclonal anti-alpha-hCG antibody labelled sheep erythrocytes. The second is a 'dot' enzyme immuno-assay employing dip-stick (plastic strips pasted with nitrocellulose pads) coated with monoclonal anti-beta-hCG antibody. Anti-alpha-hCG monoclonal-alkaline phosphatase conjugate was used to reveal hCG bound to solid surface. The assays can be performed by 'one-step' or 'two-step' procedures. Erythro-immunoassay as well as 'dot' enzyme immunoassay was able to detect in urine as low as 10 mIU hCG/ml. A good correlation was observed between the values obtained by these two methods as well as 'two-step' sandwich enzyme immunoassay on 47 urine samples.     

Human chorionic gonadotropin in cancer

Human chorionic gonadotropin (hCG) is mainly used for detection and monitoring of pregnancy and pregnancy-related disorders but it is also an extremely sensitive and specific marker for trophoblastic tumors of placental and germ cell origin. Thus treatment of relapsing choriocarcinomas and testicular germ cell tumors is often initiated on the basis of rising hCG levels even in the absence of clinical or histological evidence of a relapse. While these tumors mostly produce the intact heterodimeric hormone consisting of an alpha (hCGalpha), and a beta subunit (hCGbeta), many nontrophoblastic tumors produce only hCGbeta This is usually a sign of aggressive disease and elevated serum levels of hCGbeta are strongly associated with poor prognosis. Elevated serum levels are observed in 45-60% of patients with biliary and pancreatic cancer and in 10-30% of most other cancers. Methods that detect hCG and hCGbeta together are mainly used for measurement of hCG-like immunoreactivity in serum. However, the reference range for hCG is 5-8 fold higher than that for hCGbeta and thus moderately elevated levels can be identified only with a specific and sensitive hCGbeta assay.     

Importance of the intracellular detection of alpha-fetoprotein and beta-human chorionic gonadotropin in a testicular tumor using immunoperoxidase

30 patients with testicular cancer (20 seminoma, 10 non-seminomatous tumours) were investigated with respect to the determination of alpha-fetoprotein and beta-human chorionic gonadotropin in formalin-fixed slices by means of the indirect immunoperoxidase technique. The immunohistochemical method detected HCG-producing cells in 8 seminoma, whereas routine histology revealed syncytiotrophoblastic giant cells in 4 cases only. The immunohistochemical results and the serum AFT, and/or HCG values obtained by radioimmunoassay corresponded well in all patients with non-seminomatous tumours. Direct evidence of HCG production in the primary tumour can be important in therapeutic decisions, especially in patients with seminoma. The direct proof of AFP in the primary tumour might answer in the future the question of the incidence and the prognostic impact of yolk sac tumour parts in malignant teratomas.     

Monoclonal antibodies for the treatment of asthma

Asthma is a chronic inflammatory disease of the airways which can have a detrimental effect on quality of life and in extreme cases cause death. Although the majority of patients can control their asthma symptoms with a combination of steroids and beta agonists there is still a group of patients whose asthma remains symptomatic despite the best available treatment. These severe asthmatic patients represent the unmet medical need in asthma and are the focus of those developing novel monoclonal antibody based drugs. The complex networks of cytokines and cells involved in the pathology of asthma provide plenty of scope for intervention with monoclonal antibody based drugs which are able to block cytokine or chemokine receptor interactions, deplete cells expressing a specific receptor or block cell/cell interactions. At present anti-IgE (Xolair©) is the only monoclonal antibody based drug approved for the treatment of asthma. However, a number of other antibody based drugs have been clinically tested in asthma including anti-IL-5, anti-IL-4, anti-IL-13, anti-TNFα, anti-CCR3, anti-CCR4 and anti-OX40L. This review will examine the development of these monoclonal antibody based therapies. Since many of these therapies have targeted key pathways in asthma pathology these studies provide information on patient stratification and asthma pathology.     

Monoclonal antibodies for the treatment of osteoporosis

Introduction: Osteoporosis is a systemic skeletal disorder that weakens bones and increases the risk of fractures. It is caused by perturbations of bone remodeling, the coupled process whereby bone is continually resorbed and formed in small discrete units. Despite the availability of cost-effective pharmacological agents that reduce fracture risk, many patients who could benefit from treatment are not receiving it. Advances in the understanding of the molecular regulators of bone remodeling have led to the identification of new targets for therapeutic intervention. Monoclonal antibodies directed to these targets have recently been developed, providing new ways of modulating bone remodeling that may provide additional benefits beyond previously available therapy.

Areas covered: An approved fully human monoclonal antibody to receptor activator of nuclear factor-κB ligand, the principal regulator of osteoclastic bone resorption, reduces the risk of fractures in postmenopausal women with osteoporosis. Monoclonal antibodies in development include inhibitors of sclerostin and Dickhopf1, with osteoanabolic activity that may be beneficial in the treatment of osteoporosis.

Expert opinion: Monoclonal antibodies to molecular regulators of bone remodeling represent a new class of compounds for the management of osteoporosis and other skeletal disorders associated with an imbalance of bone resorption and formation.     

Monoclonal antibodies for the treatment of osteoarthritis

ABSTRACT

Introduction: Osteoarthritis (OA) is a multifactorial chronic joint disease, and so far, there are no approved disease-modifying anti-OA drugs (DMOADs). There is an urgent need to develop therapies for different phenotypes of OA. Monoclonal antibodies (mAb) may slow structural progression, control inflammation and relieve pain, and thus have the potential to be DMOADs.

Areas covered: In this review, the authors searched the literature on PubMed, EMBASE and the Cochrane Library using keywords, including mAbs, biological agents, OA and osteoarthritis, electronically up to May 2016. They also included abstracts of international conferences. Furthermore, they reviewed experimental and clinical studies of various mAbs targeting different pathological mechanisms of OA, including ADAMTS, Interleukine-1, tumour necrosis factor, never growth factor and vascular endothelial growth factor.

Expert opinion: MAbs for the treatment of OA are under intense investigation and the results for some mAbs (e.g., anti-nerve growth factor mAbs, anti- vascular endothelial growth factor mAbs) are promising. The authors believe that mAb therapy can be a targeted therapeutic approach for the treatment of OA. Future clinical trials are required to evaluate the therapeutic efficacy of these agents by the appropriate selection of specific phenotype for targeted therapy based on the mechanism of drug action.     

Perinatal outcome in pregnancies with a positive serum screening for Down's syndrome due to elevated levels of free beta-human chorionic gonadotropin.

OBJECTIVE: To evaluate the potential clinical use of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and uterine artery Doppler investigation to screen for placenta-related adverse outcome in pregnancies at positive risk for Down's syndrome at 15-18 weeks. DESIGN: A cohort of 329 consecutive pregnant women with a singleton viable pregnancy and a positive risk for Down's syndrome was retrospectively investigated. This group was obtained from an unselected population of 3952 women attending the same hospital over a 2-year period. Using the results of this first analysis, we selected a group of 26 women with unexplained high levels of free beta-hCG and followed them prospectively with monthly ultrasound and uterine artery Doppler examinations. RESULTS: In the retrospective cohort, risk ratios stratified for maternal serum beta-hCG multiple of the median (MoM) values indicated that the highest incidence of adverse pregnancy outcome was in those women with values of > or = 5.0. In the prospective study, pregnancy outcome was complicated by uteroplacental disorders in eight cases. Analysis of the Doppler investigation indicated that, in women with a very high level of hCG, an abnormally high uterine artery pulsatility index (PI) had lower sensitivity and negative predictive value than early diastolic notch, whereas the specificity and positive predictive value were higher for a high uterine artery PI. CONCLUSIONS: These findings suggest an association between a high level of maternal serum beta-hCG at 15-18 weeks, the presence of an early diastolic notch in the uterine artery flow velocity waveform and adverse pregnancy outcome due to abnormal development of the uteroplacental circulation. Young women with an unexplained high beta-hCG level would benefit, apart from detailed sonography of the fetus and/or karyotyping, from uterine Doppler investigation and counselling about the follow-up and management of placenta-related pregnancy disorders.     

Analytic evaluation of the beta-human chorionic gonadotropin assay on the Abbott IMx and Elecsys2010 for its use in doping control

OBJECTIVES: The principal objective of this study was to compare the analytical performance of the Elecsys2010 (Roche Diagnostics) system with the IMx (Abbott laboratories) system for beta-hCG assay in order to assess its possible utility as a confirmation test for the quantitative measurement of beta-hCG in urine for doping control purposes. DESIGN AND METHODS: Urine samples with spiked standard known concentrations of beta-hCG and different urine samples from athletes were used in order to determine the calibration curve stability and linearity, detection limit, total, within-run and between-run precision, and method comparison for the IMx and Elecsys2010 systems for beta-hCG assay, along with the stability of samples, at room temperature and at 4 degrees C. RESULTS: The IMx assay was linear up to 500 IU/L, whereas the Elecsys2010 assay was linear up to 1000 IU/L. The detection limit for the IMx and Elecsys2010 systems were 0.75 IU/L and 0.25 IU/L, respectively. The total precision of the IMx and Elecsys2010 systems were 相似文献   

False-positive pregnancy test after passive transfusion of beta-human chorionic gonadotropin from donor red blood cells during erythrocytapheresis

BACKGROUND: Patients transfused with blood products may passively receive soluble antibodies, proteins, and other analytes that persist during the collection, processing, and transfusion of the blood product. In this report, a female patient who received transfusion of five red blood cell (RBC) units during erythrocytapheresis later demonstrated an unexpected positive result in assays for the beta-subunit of human chorionic gonadotropin (bHCG), a screening test for pregnancy. The result caused postponement of an elective surgical procedure. A follow-up test 1 week later was negative. STUDY DESIGN AND METHODS: To investigate the possibility of passive transfusion of the hormone from a donor RBC unit, a sample from each of the units transfused was assayed for the level of bHCG. RESULTS: One of the 5 units transfused to the patient had a high level of bHCG. The observed bHCG level in the recipient was found to be comparable to the predicted level, given the donor's plasma bHCG level and accounting for the dilution factors in the preparation of the RBC unit and the erythrocytapheresis procedure and the in vivo t((1/2)) of the hormone. CONCLUSION: The donor, who was unaware of her pregnancy status at the time of donation, harbored a high bHCG level that caused the positive test result in the recipient patient's serum and urine. If an unexpected analyte or serology is detected in a recipient of a blood transfusion, it is important to consider the possibility of passive transfusion of the analyte.     

Monoclonal antibodies for brain tumour treatment

Conventional treatment of brain tumours includes surgical, radiotherapeutic and chemotherapeutic modalities. Nonetheless, the outcome of patients with brain tumours, in particular glioblastoma, remains poor. Immunotherapy with armed or unarmed monoclonal antibodies targeting tumour-specific antigens has emerged in the last two decades as a novel potential adjuvant treatment for all types of neoplasia. Many challenges to its implementation as a safe and viable therapy for brain tumours still need to be addressed; nevertheless, results from ongoing Phase I/II clinical trials are encouraging, as disease stabilisation and patient survival prolongation have been observed. Advances in preclinical and clinical research indicate that treatment of brain tumours with monoclonal antibodies can be increasingly adjusted to the characteristics of the targeted tumour and its environment. This aspect relies on the careful selection of the target antigen and corresponding specific monoclonal antibody, and antibody format (size, class, affinity), conjugation to the appropriate toxin or radioactive isotope (half-life, range), and proper compartmental administration.     

Monoclonal antibodies for brain tumour treatment

Conventional treatment of brain tumours includes surgical, radiotherapeutic and chemotherapeutic modalities. Nonetheless, the outcome of patients with brain tumours, in particular glioblastoma, remains poor. Immunotherapy with armed or unarmed monoclonal antibodies targeting tumour-specific antigens has emerged in the last two decades as a novel potential adjuvant treatment for all types of neoplasia. Many challenges to its implementation as a safe and viable therapy for brain tumours still need to be addressed; nevertheless, results from ongoing Phase I/II clinical trials are encouraging, as disease stabilisation and patient survival prolongation have been observed. Advances in preclinical and clinical research indicate that treatment of brain tumours with monoclonal antibodies can be increasingly adjusted to the characteristics of the targeted tumour and its environment. This aspect relies on the careful selection of the target antigen and corresponding specific monoclonal antibody, and antibody format (size, class, affinity), conjugation to the appropriate toxin or radioactive isotope (half-life, range), and proper compartmental administration.     

Monoclonal antibodies. Use in detection and treatment of cancer

Monoclonal antibodies are homogeneous immunoglobulin proteins produced to a preselected antigen. These antibodies react to specific sites on the antigen and, if the antigen is part of the cell surface, mediate a destructive response against that cell. The antibodies may be useful in patients with malignancy to detect tumor-related antigens in patient serum, to localize the presence of metastatic disease, and to serve as therapeutic agents. The technology of monoclonal antibodies is rapidly evolving and will soon be part of routine treatment of patients with malignancy.     

β-人绒毛膜促性腺激素光激化学发光免疫分析方法的建立

目的建立一种检测人血清β-人绒毛膜促性腺激素（β-HCG）浓度的光激化学发光免疫分析方法。方法采用2株针对不同抗原表位的抗β-HCG抗体,其中一株抗体用来包被发光微粒,另一株抗体标记生物素,以双抗体夹心法检测人血清中的β-HCG浓度,并与Beckman-Coulter公司试剂（化学发光法）进行比较。结果发光微粒浓度为100μg/mL、生物素标记抗体浓度为7μg/mL时,检测范围为0~1 000 mIU/mL,灵敏度为0.16 mIU/mL,平均回收率为100.3%,批内变异系数（CV）为0.80%~3.99%,批间CV为2.25%,与TSH、FSH和LH的交叉反应率低,稳定性较好,与化学发光法的符合率好（r=0.99）。结论光激化学发光免疫分析方法测定β-HCG具有较高灵敏度、精密度和准确性,与化学发光法的符合率较好,适用于临床测定。     

Simultaneous determination of alpha-fetoprotein and free beta-human chorionic gonadotropin by element-tagged immunoassay with detection by inductively coupled plasma mass spectrometry

BACKGROUND: An inductively coupled plasma mass spectrometry (ICP-MS)-based immunoassay has been proposed independently by Baranov et al. (Anal Chem 2002;74:1629-36) and our group, but the applicability of this method for multianalyte analysis in clinical samples has not been fully illustrated. We developed a dual-label immunoassay method for the simultaneous determination of alpha-fetoprotein (AFP) and free beta-human chorionic gonadotropin (hCGbeta) in human serum. METHODS: Monoclonal antibodies immobilized on microtiter plates captured AFP and hCGbeta, which were detected by use of Eu(3+)-labeled anti-AFP and Sm(3+)-labeled anti-hCGbeta monoclonal antibodies. Eu(3+) and Sm(3+) were dissociated from the immunocomplex with HNO(3) solution (10 mL/L) and delivered by peristaltic pump to the ICP mass spectrometer. RESULTS: The measurable ranges of AFP and hCGbeta were 4.6-500 and 5.0-170 microg/L, respectively, with detection limits of 1.2 and 1.7 microg/L (3 SD above mean of zero calibrator), respectively. The intraassay imprecision (CV) for AFP was 8.3%, 4.0%, and 2.7% at 16.3, 86, and 354 microg/L, respectively, and the interassay CV was 10%, 5.7%, and 3.5%. For hCGbeta, the intraassay CV was 5.4%, 6.4%, and 3.1%, respectively, at 10.5, 45.2, and 105 microg/L, and the interassay CV was 7.2%, 8.0%, and 3.7%. Comparison with IRMAs for AFP and hCGbeta yielded correlation coefficients (r(2)) of 0.97 and 0.95. CONCLUSIONS: Two proteins can be measured simultaneously by immunoassays using two rare earth elemental tags (Eu(3+) and Sm(3+)) and ICP-MS detection. The multielement capability and the multiple potential elemental labels make ICP-MS attractive for multianalyte immunoassays. Implementation of ICP-MS-linked immunoassays may be relatively straightforward because the labeling and immunoreaction procedures have been well developed for clinical time-resolved immunofluorometric assays.