Biological and clinical aspects of soluble transferrin receptor

Abstract

Soluble transferrin receptor (sTfR), one of the main regulators of cellular iron homeostasis, is the truncated form of the tissue receptor that is encoded by the human TfR gene (chromosome 3). Serum sTfR levels are determined to detect iron deficiency (ID) in inflammatory states and in anemia of chronic disease (ACD) and to monitor the efficiency of erythropoietin (EPO) treatment. The levels of sTfR reflect the receptor density on cells (tissue iron status) and the number of cells with receptors (erythropoietic activity). Currently assays for the measurements of sTfR are standardized using different reference materials, give different results, and have different reference ranges. The recent development of a lyophilized preparation of recombinant soluble transferrin receptor (rsTfR) as a World Health Organization (WHO) reference reagent should help in the standardization of sTfR immunoassays. This article reviews the general characteristics of (s)TfR, the assays for sTfR, biological confounders in the assays, and the clinical applications for measuring sTfR.

Assessment of human iron status: A cross-sectional study comparing the clinical utility of different laboratory biomarkers and definitions of iron deficiency in daily practice

“…The aim of this study was to compare ferritin and TSAT with the sTfR/log ferritin ratio and CHr, also known as 17,18] to serve as biomarkers in patients with ID. Furthermore, separate logistic regression models, for patients without (C-reactive protein [CRP-] value ≤ 0.5 mg/dl) and with acute-phase reaction (CRP-value N 0.5 mg/dl) were used to predict functional ID in clinical practice.…”

Enhanced sandwich immunoassay using antibody-functionalized magnetic iron-oxide nanoparticles for extraction and detection of soluble transferrin receptor on a photonic crystal biosensor

“…Binding ratios were calculated in terms of sTfR:fAb-IONs molecules. The molar concentration of fAbIONs was provided by Ocean NanoTech and the molecules of sTfR were calculated by using the molecular weight (85 kDa) of sTfR (Speeckaert et al, 2010).…”

Soluble Transferrin Receptor levels of Apparently Healthy Adults in Port Harcourt, Nigeria

“…[3] Transferrin receptors are expressed on all dividing cells and its rate of synthesis is related to the cell's iron requirement. [4] There are are up to 10,000 -100,000 sTFr molecules per cell in actively dividing cells especially in erythroid precursors in the bone marrow and placental syncythiotrophoblast. sTfR concentration increases up to two folds in iron deficiency, making it an important tool for detecting early tissue iron deficiency before onset of anaemia.…”