Recombinant human thyrotropin stimulates thyroid function and radioactive iodine uptake in the rhesus monkey

The administration of bovine TSH to stimulate thyroid radioactive iodine uptake to detect functioning thyroid tissue in man after surgery for thyroid cancer is rarely, if ever, used, due to allergic reactions and/or the development of TSH antibodies. Human (h) TSH would be far less likely to induce allergic reactions or TSH antibodies. Recombinant hTSH (rec-hTSH) was produced by a line of Chinese hamster ovary cells that had been transfected with cDNA for the two subunit proteins that comprise hTSH. The present study was carried out to determine the half-life of rec-hTSH in the monkey and its ability to stimulate thyroid function. The half-life of rec-hTSH after iv administration was approximately 63 min for the rapid phase and 326 min for the slow phase. After three daily im injections of 2 U rec-hTSH to two monkeys, serum T4 concentrations increased several-fold, and serum T3 increased 2-3 times above basal values. The 6 and 20 h thyroid 123I uptakes doubled after rec-hTSH administration. These results demonstrate the biological efficacy of rec-hTSH administered to the monkey and strongly suggest that rec-hTSH will be effective in stimulating thyroid function in man

Performance characteristics of five immunoassays for SARS-CoV-2: a head-to-head benchmark comparison

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic in 2020. Testing is crucial for mitigating public health and economic effects. Serology is considered key to population-level surveillance and potentially individual-level risk assessment. However, immunoassay performance has not been compared on large, identical sample sets. We aimed to investigate the performance of four high-throughput commercial SARS-CoV-2 antibody immunoassays and a novel 384-well ELISA.We did a head-to-head assessment of SARS-CoV-2 IgG assay (Abbott, Chicago, IL, USA), LIAISON SARS-CoV-2 S1/S2 IgG assay (DiaSorin, Saluggia, Italy), Elecsys Anti-SARS-CoV-2 assay (Roche, Basel, Switzerland), SARS-CoV-2 Total assay (Siemens, Munich, Germany), and a novel 384-well ELISA (the Oxford immunoassay). We derived sensitivity and specificity from 976 pre-pandemic blood samples (collected between Sept 4, 2014, and Oct 4, 2016) and 536 blood samples from patients with laboratory-confirmed SARS-CoV-2 infection, collected at least 20 days post symptom onset (collected between Feb 1, 2020, and May 31, 2020). Receiver operating characteristic (ROC) curves were used to assess assay thresholds.At the manufacturers' thresholds, for the Abbott assay sensitivity was 92·7% (95% CI 90·2–94·8) and specificity was 99·9% (99·4–100%); for the DiaSorin assay sensitivity was 96·2% (94·2–97·7) and specificity was 98·9% (98·0–99·4); for the Oxford immunoassay sensitivity was 99·1% (97·8–99·7) and specificity was 99·0% (98·1–99·5); for the Roche assay sensitivity was 97·2% (95·4–98·4) and specificity was 99·8% (99·3–100); and for the Siemens assay sensitivity was 98·1% (96·6–99·1) and specificity was 99·9% (99·4–100%). All assays achieved a sensitivity of at least 98% with thresholds optimised to achieve a specificity of at least 98% on samples taken 30 days or more post symptom onset.Four commercial, widely available assays and a scalable 384-well ELISA can be used for SARS-CoV-2 serological testing to achieve sensitivity and specificity of at least 98%. The Siemens assay and Oxford immunoassay achieved these metrics without further optimisation. This benchmark study in immunoassay assessment should enable refinements of testing strategies and the best use of serological testing resource to benefit individuals and population health.Public Health England and UK National Institute for Health Research