Archive for February, 2018

Comparison of a New Multiplex Immunoassay for Measurement of Ferritin, Soluble Transferrin Receptor, Retinol-Binding Protein, C-Reactive Protein and α1-Acid-glycoprotein Concentrations against a Widely-Used s-ELISA Method

Karakochuk CD, Henderson AM, Samson KLI, Aljaadi AM, Devlin AM, Becquey E, Wirth JP, Rohner F

February 2018 – Diagnostics

Recently, a multiplex ELISA (Quansys Biosciences) was developed that measures ferritin, soluble transferrin receptor (sTfR), retinol-binding protein (RBP), C-reactive protein (CRP), α1-acid glycoprotein (AGP), thyroglobulin, and histidine-rich protein 2. Our primary aim was to conduct a method-comparison study to compare five biomarkers (ferritin, sTfR, RBP, CRP, and AGP) measured with the Quansys assay and a widely-used s-ELISA (VitMin Lab, Willstaett, Germany) with use of serum samples from 180 women and children from Burkina Faso, Cambodia, and Malaysia. Bias and concordance were used to describe the agreement in values measured by the two methods. We observed poor overall agreement between the methods, both with regard to biomarker concentrations and deficiency prevalence estimates. Several measurements were outside of the limit of detection with use of the Quansys ELISA (total n = 42 for ferritin, n = 2 for sTfR, n = 0 for AGP, n = 5 for CRP, n = 22 for RBP), limiting our ability to interpret assay findings. Although the Quansys ELISA has great potential to simplify laboratory analysis of key nutritional and inflammation biomarkers, there are some weaknesses in the procedures. Overall, we found poor comparability of results between methods. Besides addressing procedural issues, additional validation of the Quansys against a gold standard method is warranted for future research.

Thyroid Function and Growth – The Mechanisms of Iodine

Farebrother J, Rohner F

February 2018 – The Biology of the First 1,000 days

Iodine deficiency used to be highly prevalent in many parts of the world until salt iodization programs and other prevention strategies were implemented and scaled up, beginning in the 1980s in most countries. Great progress toward reducing iodine deficiency and its consequences has been achieved since; however, large numbers of people continue to be affected. This chapter examines mechanisms of iodine, thyroid hormones, and growth during the “1,000-day window”, the period between conception and when a child is 2 years of age.