Development of a certified reference material for anti-β2-glycoprotein I IgG – commutability studies

AbstractObjectivesIn this paper, we describe the steps followed for the development of a certified reference material for immunoglobulin G antibodies against β2-glycoprotein I (also known as apolipoprotein H). These steps include processing of the material, commutability, the impact of dilution, the appropriate reconstitution conditions, homogeneity and stability during transport and storage.MethodsWe analysed 69 clinical samples from patients suffering from antiphospholipid syndrome with several commercial enzyme-linked immunosorbent assays (ELISA) purchased from in vitro diagnostic manufacturers.ResultsAnalysis of the results indicated that the candidate reference material can be safely freeze-dried, and that the user should carefully follow the reconstitution instructions as small changes in e.g. temperature may have unwanted effects. The statistical analysis of the commutability studies indicated that the analytical response of the reference material upon dilution is similar to that of clinical samples, and that correlation between results may differ from assay to assay. Finally yet importantly, the presented and developed candidate reference material is commutable for most assays tested, homogeneous and stable.ConclusionsImmunoglobulin G antibodies against β2-glycoprotein I are associated with a higher risk of thrombosis and pregnancy complications. Their measurement is essential for the diagnosis and monitoring of antiphospholipid syndrome. These antibodies are detected by specific immunoassays, routinely used in clinical diagnostics, but various of these methods show enormous variability, in part due to the lack of a reference material.

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The impact of uncertainty in the elemental composition of the certified reference material on gamma spectrometry

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-013-2781-7 ◽

2013 ◽

Vol 299 (1) ◽

pp. 551-558 ◽

Cited By ~ 4

Author(s):

Maurice Miller ◽

Mitko Voutchkov

Keyword(s):

Reference Material ◽

Elemental Composition ◽

Certified Reference Material ◽

Gamma Spectrometry ◽

The Impact

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Systematic comparison of δ13C measurements of testosterone and derivative steroids in a freeze-dried urine candidate reference material for sports drug testing by gas chromatography/combustion/isotope ratio mass spectrometry and uncertainty evaluation usi

Rapid Communications in Mass Spectrometry ◽

10.1002/rcm.4983 ◽

2011 ◽

Vol 25 (11) ◽

pp. 1641-1651 ◽

Cited By ~ 8

Author(s):

Ellaine Munton ◽

John Murby ◽

D. Brynn Hibbert ◽

Rebeca Santamaria-Fernandez

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Reference Material ◽

Isotope Ratio ◽

Drug Testing ◽

Isotope Ratio Mass Spectrometry ◽

Uncertainty Evaluation ◽

Candidate Reference Material ◽

Systematic Comparison ◽

Freeze Dried

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Pathophysiology of β2-glycoprotein I in antiphospholipid syndrome

Lupus ◽

10.1177/0961203310361352 ◽

2010 ◽

Vol 19 (4) ◽

pp. 379-384 ◽

Cited By ~ 17

Author(s):

E. Matsuura ◽

L. Shen ◽

Y. Matsunami ◽

N. Quan ◽

M. Makarova ◽

...

Keyword(s):

Vascular Disease ◽

Antiphospholipid Syndrome ◽

Mechanism Of Action ◽

Antiphospholipid Antibodies ◽

Physiological Role ◽

Therapeutic Strategies ◽

Physiological Functions ◽

Glycoprotein I ◽

The Impact

Since β2-glycoprotein I (β2GPI) was described as the major antigenic target for antiphospholipid antibodies, many studies have focused their attention to the physiological role of β2GPI and anti-β2GPI antibodies on autoimmune-mediated thrombosis. Studies reporting the physiological role of β2GPI have been numerous, but the exact mechanism of action(s) has yet to be completely determined. β2GPI’s epitopes for anti-β2GPI autoantibodies have been characterized, however, not all of the heterogeneous anti-β2GPI antibodies are pathogenic. The pathophysiologic role of β2GPI has been reported in the fields of coagulation, fibrinolysis, angiogenesis, and atherosclerosis. Our understanding of the impact of β2GPI, its metabolites and autoantibodies to β2GPI on these physiological functions may contribute to the development of better therapeutic strategies to treat and prevent autoimmune-mediated atherothrombotic vascular disease. Lupus (2010) 19, 379—384.

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The preparation of a certified reference material of polar pesticides in freeze-dried water (CRM 606)

Fresenius Journal of Analytical Chemistry ◽

10.1007/s002160051263 ◽

1999 ◽

Vol 363 (7) ◽

pp. 632-640 ◽

Cited By ~ 3

Author(s):

A. Martín-Esteban ◽

P. Fernández ◽

C. Cámara ◽

G. N. Kramer ◽

E. A. Maier

Keyword(s):

Reference Material ◽

Certified Reference Material ◽

Polar Pesticides ◽

Freeze Dried

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Certified Reference Material for Analytical Quality Assurance of Minor and Trace Elements in Food and Related Matrixes Based on a Typical Japanese Diet: Interlaboratory Study

Journal of AOAC International ◽

10.1093/jaoac/84.4.1202 ◽

2001 ◽

Vol 84 (4) ◽

pp. 1202-1208 ◽

Cited By ~ 4

Author(s):

Jun Yoshinaga ◽

Masatoshi Morita ◽

Masae Yukawa ◽

Kunio Shiraishi ◽

Hisao Kawamura ◽

...

Keyword(s):

Trace Elements ◽

Quality Assurance ◽

Reference Material ◽

Reference Values ◽

Certified Reference Material ◽

Analytical Quality ◽

Analytical Quality Assurance ◽

Minor And Trace Elements ◽

Freeze Dried ◽

Japanese Diet

Abstract A Certified Reference Material (CRM) was prepared at the National Institute for Environmental Studies (NIES), Japan, in collaboration with the National Institute of Radiological Sciences (NIRS), Japan, for the analytical quality assurance of minor and trace elements in food and related matrixes. The starting material for the CRM was all food served in 29 households in Japan over two 3-day periods in 1997–1998, and thus the CRM represented a typical Japanese diet. All foods (meals, snacks, and beverages) were homogenized, freeze-dried, pulverized, blended, dispensed into 1100 bottles, and sterilized. The within- and between-bottle homogeneity of the prepared CRM was satisfactory for most of the elements. The concentrations of 14 elements (Na, Mg, K, Ca, Mn, Cu, Zn, As, Se, Sr, Cd, Sn, Ba, and U) were certified based on a collaborative analysis involving NIES, NIRS, and 20 other laboratories. Reference values were given for the concentrations of 12 additional elements (P, Cl, Fe, Co, Ni, Br, Rb, Mo, I, Cs, Pb, and Th). The elements certified and those given reference values include minerals, essential trace elements, contaminant elements, and long-lived radionuclides. Thus, this CRM is of practical value in the quality assurance of element analysis of foods and diets in nutritional, environmental, and radiological research.

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AB1051 Development of a Certified Reference Material for Autoimmune Antibodies (Anti-Myeloperoxidase Immunoglobulin G in Human Serum)

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2015-eular.1596 ◽

2015 ◽

Vol 74 (Suppl 2) ◽

pp. 1250.2-1251

Author(s):

E. Monogioudi ◽

G. Martos ◽

D.P. Hutu ◽

S. Trapmann ◽

A. Wiik ◽

...

Keyword(s):

Reference Material ◽

Human Serum ◽

Certified Reference Material ◽

Immunoglobulin G ◽

Autoimmune Antibodies

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Certified reference material against PR3 ANCA IgG autoantibodies. From development to certification

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2018-1095 ◽

2019 ◽

Vol 57 (8) ◽

pp. 1197-1206 ◽

Cited By ~ 3

Author(s):

Evanthia Monogioudi ◽

Joanna Sheldon ◽

Pier Luigi Meroni ◽

Dana Petronela Hutu ◽

Heinz Schimmel ◽

...

Keyword(s):

Reference Material ◽

Certified Reference Material ◽

Certified Reference Materials ◽

Feasibility Studies ◽

Autoimmune Disorder ◽

Accurate Diagnosis ◽

Clinical Samples ◽

Appropriate Use ◽

Comparability Of Results

Abstract Background The importance of the standardisation of immunoassays for autoantibodies has been widely discussed. The appropriate use of certified reference materials (CRM) could contribute to a more accurate diagnosis and follow-up of a series of diseases such as small vessel-associated vasculitis. This is a systemic autoimmune disorder during which two autoantibodies can be present, MPO ANCA IgG and PR3 ANCA IgG. Results from different commercially available immunoassays used for PR3 ANCA IgG measurement can vary significantly. Therefore the potential for improvement using a suitable certified reference material was assessed and led to the development of a CRM. Methods Thirty clinical samples were evaluated using 10 immunoassays. The correlation between results from these assays was assessed in a pairwise manner. Feasibility studies were conducted in order to find a reference material format most suitable for the preparation of a CRM. Results The evaluation of two sets of 30 clinical samples with 10 assays showed that differences between assays can result in different interpretations for individual clinical samples. Most of the samples had the same result classification in all assays. However, six of the samples tested led to inconsistent results. Conclusions The correlation between results from clinical samples was systematically good for combinations of eight of those assays. Therefore, it should be possible to improve the comparability of results using a commutable CRM for calibration. Based on these studies, a final format for the CRM was selected and eventually produced and certified for its PR3 ANCA IgG content.

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IFCC Working Group Recommendations for Correction of Bias Caused by Noncommutability of a Certified Reference Material Used in the Calibration Hierarchy of an End-User Measurement Procedure

Clinical Chemistry ◽

10.1093/clinchem/hvaa048 ◽

2020 ◽

Vol 66 (6) ◽

pp. 769-778 ◽

Cited By ~ 3

Author(s):

W Greg Miller ◽

Jeffrey Budd ◽

Neil Greenberg ◽

Cas Weykamp ◽

Harald Althaus ◽

...

Keyword(s):

Reference Material ◽

Certified Reference Material ◽

Clinical Laboratory ◽

Metrological Traceability ◽

Measurement Procedure ◽

Clinical Samples ◽

End User ◽

Assigned Value ◽

The Difference ◽

Specific Correction

Abstract Establishing metrological traceability to an assigned value of a matrix-based certified reference material (CRM) that has been validated to be commutable among available end-user measurement procedures (MPs) is central to producing equivalent results for the measurand in clinical samples (CSs) irrespective of the clinical laboratory MPs used. When a CRM is not commutable with CSs, the bias due to noncommutability will be propagated to the CS results causing incorrect metrological traceability to the CRM and nonequivalent CS results among different MPs. In a commutability assessment, a conclusion that a CRM is commutable or noncommutable for use with a specific MP is made when the difference in bias between the CRM and CSs meets or does not meet a criterion for that specific MP when compared to other MPs. A conclusion regarding commutability or noncommutability requires that the magnitude of the difference in bias observed in the commutability assessment remains unchanged over time. This conclusion requires the CRM to be stable and no substantive changes in the MPs. These conditions should be periodically reverified. If an available CRM is determined to be noncommutable for a specific MP, that CRM can be used in the calibration hierarchy for that MP when an appropriately validated MP-specific correction for the noncommutability bias is included. We describe with examples how a MP-specific correction and its uncertainty can be developed and applied in a calibration hierarchy to achieve metrological traceability of results for CSs to the CRM’s assigned value.

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Human Urine Certified Reference Material for Arsenic Speciation

Clinical Chemistry ◽

10.1093/clinchem/46.11.1781 ◽

2000 ◽

Vol 46 (11) ◽

pp. 1781-1786 ◽

Cited By ~ 20

Author(s):

Jun Yoshinaga ◽

Amit Chatterjee ◽

Yasuyuki Shibata ◽

Masatoshi Morita ◽

John S Edmonds

Keyword(s):

Reference Material ◽

Biological Monitoring ◽

Certified Reference Material ◽

Human Urine ◽

Arsenic Speciation ◽

Arsenic Exposure ◽

Inorganic Arsenic ◽

Speciation Analysis ◽

Dimethylarsinic Acid ◽

Freeze Dried

Abstract Background: Chemical speciation analysis is essential for the biological monitoring of inorganic arsenic exposure using urine as indicator medium. There is increasing demand for a certified reference material (CRM) of urine matrix for arsenic speciation. Methods: Urine (10 L) was collected from non-occupationally exposed Japanese males. We prepared 954 bottles of urine, each containing ∼10 mL, after filtering and blending the urine stock. The urine in each bottle was freeze-dried. Between-bottle homogeneity was confirmed by measuring the concentrations of selected minor and trace elements in the material and subsequent statistical analysis. Certification was based on a collaborative analysis involving 15 laboratories. Results: Certified values were determined for arsenobetaine (0.069 ± 0.012 mg As/L), dimethylarsinic acid (0.036 ± 0.009 mg As/L), and total arsenic (0.134 ± 0.011 mg/L) as well as for total selenium (0.059 ± 0.005 mg/L) and zinc (0.62 ± 0.05 mg/L), based on the analytical values from the collaborating laboratories. Reference values are given for copper (0.010 mg/L) and lead (0.0011 mg/L), based on definitive analysis at the National Institute for Environmental Studies (NIES). Conclusions: The present CRM, NIES CRM No. 18 Human Urine, is the first human urine CRM for arsenic speciation and will be of value for analytical quality assurance of the biological monitoring of arsenic exposure.

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