The International Reference Preparation of Calcitonin, Human, for Bioassay: Assessment of material and definition of the International Unit

1980 ◽  
Vol 93 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Rose E. Gaines Das ◽  
Joan M. Zanelli
Keyword(s):  
Collaborative Study ◽  
World Health ◽  
Human Calcitonin ◽  
International Unit ◽  
International Reference ◽  
Reference Preparation ◽  
Definition Of ◽  
Health Organization ◽  
International Collaborative Study

Abstract. An international reference material is required for bioassays of preparations of synthetic human calcitonin for administration to man and for use in immunoassays. A preparation of synthetic human calcitonin in ampoules coded 70/234 (previously widely used as the MRC Research Standard) has been examined in an international collaborative study involving 7 laboratories in 6 countries. The results of 34 in vivo bioassays with two other preparations of synthetic human calcitonin showed that this preparation was suitable to serve as a standard. With the agreement of the participants in the collaborative study, the batch of ampoules, code 70/234, was established in 1978 by the World Health Organization as the International Reference Preparation of Calcitonin, Human, for Bioassay. The International Unit of human calcitonin was defined as the activity contained in one ampoule of this preparation, thus maintaining continuity of the unit of the research standard.

Establishment of the second international standards for porcine and human calcitonins: report of the international collaborative study

1993 ◽  
Vol 128 (5) ◽  
pp. 443-450 ◽  
Author(s):  
Joan M Zanelli ◽  
Rose E Gaines-Das ◽  
P Corran
Keyword(s):  
World Health Organization ◽  
Collaborative Study ◽  
International Standards ◽  
World Health ◽  
International Reference ◽  
International Standard ◽  
Reference Preparation ◽  
Health Organization ◽  
International Collaborative Study

The biological potency of calcitonins in clinical use in long-term treatment of Paget's disease of bone and, increasingly, in osteoporosis is usually expressed in international units defined by the relevant World Health Organization international reference preparation. The international reference preparations for porcine and human calcitonins were ampouled in 1970 and stocks are now exhausted. Replacement standards were ampouled in 1989 and have been evaluated and calibrated by an international collaborative study comprising 16 laboratories in 12 countries. Evaluations included high-performance liquid chromatography and in vitro bioassay; calibration of each new ampouled preparation in terms of its international reference preparation was by in vivo rat hypocalcaemia bioassay. On the basis of the results of the study and with the agreement of the participants, replacement standards were established by the Expert Committee on Biological Standardization of the World Health Organization in 1991: the international standard for porcine calcitonin (ampoule code 89/540), with an assigned potency of 0.8 international units per ampoule, and the international standard for human calcitonin, with an assigned potency of 17.5 international units per ampoule. Both international standards appeared to be sufficiently stable to serve as the international standards for in vivo biological assays. Comparison of the two species of calcitonin in the same hypocalcaemia assay showed that they were approximately equipotent when the doses were given intravenously but that the human peptide was four- to sixfold more potent than porcine calcitonin when doses were given subcutaneously, emphasizing the need to compare "like with like".

The Second International Reference Preparation of Thyroid-Stimulating Hormone, Human, for Immunoassay: calibration by bioassay and immunoassay in an international collaborative study

1985 ◽  
Vol 104 (3) ◽  
pp. 367-379 ◽  
Author(s):  
R. E. Gaines Das ◽  
A. F. Bristow
Keyword(s):  
Collaborative Study ◽  
Thyroid Stimulating Hormone ◽  
World Health ◽  
Expert Committee ◽  
International Reference ◽  
Reference Preparation ◽  
International Collaborative ◽  
Health Organization ◽  
International Collaborative Study ◽  
Second International

ABSTRACT Four batches of ampouled materials in ampoules coded 80/558, 81/502, 81/565 and 81/615 were evaluated by 22 laboratories in nine countries in an international collaborative study for their suitability to serve as a replacement for the First International Reference Preparation (IRP) of TSH, Human, for Immunoassay. The ampouled preparations were calibrated by immunoassay and bioassay. The preparation coded 80/558 had satisfactory stability and contained acceptably low levels of contamination with FSH and LH. Estimates of the immunoreactive TSH content of a set of specimens of serum in terms of 80/558 showed agreement in ranking order and no increase in variability compared with estimates made by assay against the First IRP. On the basis of these results, with the agreement of the participants in the study, and with the authorization of the Expert Committee on Biological Standardization of the World Health Organization, the preparation coded 80/558 was established in 1983 as the Second International Reference Preparation of TSH, Human, for Immunoassay, with a defined potency of 37 mi.u./ampoule. Preparations coded 81/502, 81/565 and 81/615 were found suitable to serve as working standards. J. Endocr. (1985) 104, 367–379

International Collaborative Study for the Calibration of a Proposed Reference Preparation for Thromboplastin, Human Recombinant, Plain

1998 ◽  
Vol 79 (02) ◽  
pp. 439-443 ◽  
Author(s):  
Veena Chantarangkul ◽  
Barbara Negri ◽  
Marigrazia Clerici ◽  
Pier Mannuccio Mannucci ◽  
Armando Tripodi
Keyword(s):  
Collaborative Study ◽  
Mean Value ◽  
World Health ◽  
Practical Reasons ◽  
Calibration Model ◽  
Average Value ◽  
Reference Preparation ◽  
International Collaborative ◽  
Health Organization ◽  
International Collaborative Study

SummaryStocks of the International Reference Preparation (IRP) for thromboplastin, human, plain, coded BCT/253 and held by the World Health Organization (WHO) are nearly exhausted and must be replaced. For practical reasons the choice of the replacement candidate was restricted to two available human recombinant preparations which were coded as X/95 and Y/95 and calibrated in an international collaborative study involving 19 laboratories from Europe, Australia, Canada and Argentina. To minimize the differences between routes of calibration, the two candidates were calibrated against the existing WHO-IRP from human, rabbit and bovine origin and the final ISI was the resultant average value. On the basis of predefined criteria (i.e., within- and between-laboratory precision of the calibration and the conformity to the calibration model), X/95 was the preferred candidate. The assigned ISI (SE of the mean) value is 0.940 (0.0060) and the interlaboratory coefficient of variation 4.7%.

International Collaborative Study for the Establishment of the Second International Reference Preparation of Plasmin

1983 ◽  
Vol 50 (03) ◽  
pp. 645-649 ◽  
Author(s):  
P J Gaffney ◽  
M V Mussett
Keyword(s):  
Collaborative Study ◽  
World Health ◽  
Expert Committee ◽  
Glycerol Solution ◽  
International Reference ◽  
Freeze Dried ◽  
Reference Preparation ◽  
International Collaborative ◽  
International Collaborative Study ◽  
Second International

SummaryAn international collaborative study involving seven laboratories was undertaken to assess the suitability of a freeze- dried preparation of human plasmin to replace the current International Reference Preparation (IRP) for plasmin. Chromogenic and fibrinolytic assays were used by all participating laboratories to assess the potencies of the Proposed International Reference Preparation (PIRP) and two other freeze-dried plasmins, one of human and one of porcine originThe data suggest that the PIRP is a more suitable standard for plasmin than the IRP in that the former binds to fibrin whereas only 50% of the latter binds. The PIRP compared well to other plasmin preparations and the potency assays were independent of the assay procedure and substrate used. Degradation studies indicated that the PIRP was far more stable than the glycerol solution of the IRP, surviving for 12 months at 37° C with no significant loss in either amidolytic or fibrinolytic activity. The International Committee for Thrombosis and Haemostasis (Bergamo, 1982) has recommended the use of this material as a standard and it has been established by the Expert Committee on Biological Standardization of the World Health Organization as the second International Reference Preparation for Plasmin with a defined potency of 10 International Units of Plasmin per ampoule.

scholarly journals Comparison of Pituitary and Recombinant Human Thyroid-stimulating Hormone (rhTSH) in a Multicenter Collaborative Study: Establishment of the First World Health Organization Reference Reagent for rhTSH

1999 ◽  
Vol 45 (12) ◽  
pp. 2207-2215 ◽  
Author(s):  
Brian Rafferty ◽  
Rose Gaines Das
Keyword(s):  
Recombinant Dna ◽  
Collaborative Study ◽  
Thyroid Stimulating Hormone ◽  
World Health ◽  
Human Thyroid ◽  
Reference Preparation ◽  
Bioassay Data ◽  
Health Organization ◽  
And Control ◽  
Stimulating Hormone

Abstract Background: The increasing use of recombinant-DNA-derived materials in therapy and diagnosis poses a new challenge for biological standardization, that of developing reference preparations appropriate for both the native and recombinant products. Here we report the results of an international collaborative study that was carried out under the auspices of WHO to assess the suitability of a preparation of recombinant thyroid-stimulating hormone (rTSH; 94/674) to serve as a potential standard for the calibration of diagnostic immunoassays compared with the International Reference Preparation (IRP) for human TSH (80/558). Methods: Coded samples were provided to the 33 laboratories in the study, and participants were asked to perform TSH assays currently in use in their laboratories. Twenty-eight laboratories contributed 93 immunoassays in 41 different method-laboratory combinations, and an additional 5 laboratories contributed bioassay data. All data were analyzed centrally at the National Institute for Biological Standards and Control. Results: The results obtained in different laboratories and with different assay systems revealed significant variability between estimates of rTSH relative to the IRP. These ranged from 5.51 mIU (95% limits, 3.95–7.67 mIU) per ampoule by RIA to 7.15 mIU (95% limits, 6.7–7.63 mIU) per ampoule by immunofluorometric assay. However, the results showed that the assignment of a value of 6.70 mIU per ampoule of 94/674 would give reasonable continuity with the IRP in many assay systems. Conclusions: The preparation was established as the First WHO Reference Reagent for TSH, human, recombinant, to provide a means of validating assay performance and to maintain continuity with the IRP without compromising clinical data.

Standardization for four protein analytes with the Behring Nephelometer.

1988 ◽  
Vol 34 (9) ◽  
pp. 1870-1872 ◽  
Author(s):  
S B Schotters ◽  
J H McBride ◽  
D O Rodgerson ◽  
S Higgins ◽  
M Pisa
Keyword(s):  
Human Serum ◽  
World Health Organization ◽  
Serum Proteins ◽  
World Health ◽  
International Reference ◽  
The World ◽  
Reference Preparation ◽  
Primary Standards ◽  
Health Organization ◽  
Ig G

Abstract Owing to the generally higher values observed in the initial establishment of immunoglobulins (Ig) G, A, and M assays with the Behring Nephelometer, we elected to verify five commercial protein calibrators. This initial verification was performed by standardizing the Behring Nephelometer with the World Health Organization (WHO) International Reference Preparation for Human Serum Immunoglobulins G, A, and M. The instrument was also standardized for immunoglobulins and transferrin with use of the Reference Preparation for Serum Proteins (RPSP II). Analytical recoveries of the commercial calibrators varied. Also, assigned protein concentrations in both the WHO and RPSP II preparations made them unacceptable to us as benchmark calibrators for the Behring Nephelometer. Individual proteins (IgG, IgA, IgM, and transferrin) were obtained and primary standards prepared. Both transferrin and IgG were successfully standardized. However, IgA and IgM primary standards lacked 100% antigenicity, requiring removal of nonreactive IgA and IgM or reassignment of the correct value. The problem remains to find appropriate purified materials for IgA and IgM standardization.

INTERNATIONAL REFERENCE PREPARATION OF HUMAN CHORIONIC GONADOTROPHIN FOR IMMUNOASSAY: POTENCY ESTIMATES IN VARIOUS BIOASSAY AND PROTEIN BINDING ASSAY SYSTEMS; AND INTERNATIONAL REFERENCE PREPARATIONS OF THE α AND β SUBUNITS OF HUMAN CHORIONIC GONADOTROPHIN FOR IMMUNOASSAY

1980 ◽  
Vol 84 (2) ◽  
pp. 295-310 ◽  
Author(s):  
P. L. STORRING ◽  
ROSE E. GAINES-DAS ◽  
D. R. BANGHAM
Keyword(s):  
Geometric Mean ◽  
Collaborative Study ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Considerable Heterogeneity ◽  
International Reference ◽  
Reference Preparation ◽  
Α And Β Subunits

The preparation and nature of the International Reference Preparation of Human Chorionic Gonadotrophin (HCG) for Immunoassay (IRP), as well as that of a second batch of ampoules (HCG 75/589) prepared identically from the same HCG preparation, are described. A collaborative study of these materials was carried out by 11 laboratories in eight countries, using different bioassay and immunoassay methods. Using the various in-vivo and in-vitro bioassays and receptor assays, the mean log potency estimates for each method within each laboratory of the HCG content of ampoules of the IRP, in terms of the Second International Standard of Human Chorionic Gonadotrophin for Bioassay (IS), were homogeneous and gave an overall weighted geometric mean (95% confidence limits) of 650 (632–669) International Units (i.u.)/ampoule. There was considerable heterogeneity of potency estimates of the IRP in terms of the IS both within and between many of the immunoassay systems (reflecting the impurity of the IS), and hence attempts to calibrate the IRP with immunoassay systems of different specificities were invalid. Immunoassay estimates of the HCG content of preparations of serum and urine, in terms of the IRP, showed considerable heterogeneity between assay systems (although the degree of this heterogeneity was no greater than that observed using the IS as standard), but the ranking order between preparations was consistent. Confirmation was obtained that contamination of the IRP with HCG-α and HCG-β subunits was insignificant. Accelerated degradation studies of the IRP stored at increased temperatures suggested that its stability under normal storage conditions would be satisfactory. It was agreed that the IRP was suitable to serve as an international reference preparation for immunoassay, and it was assigned a unitage of 650 i.u./ampoule on the basis of bioassay calibration. Since the ampoules of HCG (75/589) did not differ significantly from the IRP in any of the assay systems studied, it appeared to be equally suitable as a reference preparation. The International Reference Preparations of the α and β Subunits of Human Chorionic Gonadotrophin for Immunoassay are also described.

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