PAWG Pilot Study on Quantification of SARS-CoV-2 Monoclonal Antibody - Part 1

• Published in: Metrologia 2022-01, Vol.59 (1A), p.8001
• Main Authors: Mi, W, Josephs, R D, Melanson, J E, Dai, X, Wang, Y, Zhai, R, Chu, Z, Fang, X, Thibeault, M-P, Stocks, B B, Meija, J, Bedu, M, Martos, G, Westwood, S, Wielgosz, R I, Liu, Q, Teo, T L, Liu, H, Tan, Y J, Öztuğ, M, Saban, E, Kinumi, T, Saikusa, K, Schneider, R J, Weller, M G, Konthur, Z, Jaeger, C, Quaglia, M, Mussell, C, Drinkwater, G, Giangrande, C, Vaneeckhoutte, H, Boeuf, A, Delatour, V, Lee, J E, O'Connor, G, Ohlendorf, R, Henrion, A, Beltrão, P J, Scapin, S M Naressi, Sade, Y B
• Format: Article
• Language: English
• Subjects: Agreements; Amino acids; Coronaviruses; COVID-19; Glycoproteins; Immune system; Immunoglobulins; Laboratories; Leucine; Mathematical analysis; Metrology; Monoclonal antibodies; Pandemics; Peptides; Phenylalanine; Proline; Proteins; Severe acute respiratory syndrome coronavirus 2; Uncertainty; Valine; Viral diseases; Viruses; Working groups
• ISSN: 0026-1394; 1681-7575
• DOI: 10.1088/0026-1394/59/1A/08001

Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P216, was coordinated by the Chinese National Institute of Metrology (NIM), National Research Council of Canada (NRC) and the Bureau International des Poids et Mesures (BIPM). Eleven Metrology Institutes or Designated Institutes and the BIPM participated in the first phase of the pilot study (Part 1). The purpose of this pilot study was to develop measurement capabilities for larger proteins using a recombinant humanized IgG monoclonal antibody against Spike glycoprotein of SARS-CoV-2 (Anti-S IgG mAb) in solution. The first phase of the study was designed to employ established methods that had been previously studies by the CCQM Protein Analysis Working Group, involving the digestion of protein down to the peptide or amino acid level. The global coronavirus pandemic has also led to increased focus on antibody quantitation methods. IgG are among the immunoglobulins produced by the immune system to provide protection against SARS-CoV-2. Anti-SARS-CoV-2 IgG can therefore be detected in samples from affected patients. Antibody tests can show whether a person has been exposed to the SARS-CoV-2, and whether or not they potentially show lasting immunity to the disease. With the constant spread of the virus and the high pressure of re-opening economies, antibody testing plays a critical role in the fight against COVID-19 by helping healthcare professionals to identify individuals who have developed an immune response, either via vaccination or exposure to the virus. Many countries have launched large-scale antibody testing for COVID-19. The development of measurement standards for the antibody detection of SARS-CoV-2 is critically important to deal with the challenges of the COVID-19 pandemic. In this study, the SARS-CoV-2 monoclonal antibody is being used as a model system to build capacity in methods that can be used in antibody quantification. Amino acid reference values with corresponding expanded uncertainty of 36.10 ± 1.55 mg/kg, 38.75 ± 1.45 mg/kg, 18.46 ± 0.78 mg/kg, 16.20 ± 0.67 mg/kg and 30.61 ± 1.30 mg/kg have been established for leucine, valine, phenylalanine, isoleucine and proline, respectively. Agreement between nearly all laboratories was achieved for the amino acid analysis within 2 to 2.5 %, with one participant achieving markedly higher results due to a technical issue found in their procedure; this re