TRANSFUSION COMPLICATIONS a-Hemoglobin stabilizing protein is not a suitable marker for a screening test for variant Creutzfeldt-Jakob disease Nigel E.J. Appleford, Kim Wilson, Fiona Houston, Lesley J. Bruce, Alex Morrison, Matthew Bishop, Kevin Chalmers, Gino Miele, Edwin Massey, Chris Prowse, Jean Manson, Robert G. Will, Michael Clinton, Ian MacGregor, and David J. Anstee BACKGROUND: A test is needed to identify blood donors who are in the preclinical phase of variant Creutzfeldt-Jakob disease (CJD). a-Hemoglobin stabi- lizing protein (AHSP; syn. ERAF, EDRF) transcript levels are reduced in the blood of mice incubating transmissible spongiform encephalopathy. STUDY DESIGN AND METHODS: Quantitative real- time polymerase chain reaction and enzyme-linked immunosorbent assay were used to measure AHSP transcript and protein levels in normal blood donors, patients with CJD, and patients with other neuronal and hematologic diseases. Temporal AHSP expression was measured in sheep incubating bovine spongiform encephalopathy (BSE). RESULTS: Quantitation of AHSP in peripheral blood from normal blood donors revealed that protein levels, but not transcript levels, are influenced by sex with higher levels found in males, suggesting posttransla- tional regulation involving the product of an X-linked gene. When AHSP mRNA and protein levels were quantitated in peripheral blood from patients with variant and sporadic CJD, no consistent differences from normal were found. Serial quantitation of AHSP in individual BSE-infected sheep did not reveal any disease-related changes. CONCLUSION: We conclude that quantitation of AHSP is not likely to be useful for detection of preclinical prion disease in man. T here is urgent need for a blood-based screen- ing test for donors in the preclinical phase of variant Creutzfeldt-Jakob disease (vCJD). a-Hemoglobin stabilizing protein (AHSP), origi- nally reported as erythroid differentiation-related factor (EDRF) and also known as erythroid-associated factor (ERAF), is a molecular chaperone that stabilizes nascent a-globin for hemoglobin A (HbA) assembly and binds free a-globin preventing toxic damage to erythroid cells. 1-3 ABBREVIATIONS: AHSP =a-hemoglobin stabilizing protein; bAHSP = bovine a-hemoglobin stabilizing protein; BSE = bovine spongiform encephalopathy; CMML = chronic myelomonocytic leukemia; CT = cycle threshold (CT); MND = motor neuron disease; MS = multiple sclerosis; PBS-T = 10 mmol/L phosphate-buffered saline-0.05 percent Tween 20; PrP = prion protein; QRT-PCR = quantitative real-time polymerase chain reaction; rbAHSP = recombinant bovine a-hemoglobin stabiliz- ing protein; rhAHSP = recombinant human a-hemoglobin sta- bilizing protein; sCJD = sporadic Creutzfeldt-Jakob disease; SNP(s) = single-nucleotide polymorphism(s); TSE(s) = transmissible spongiform encephalopathy(-ies); vCJD = variant Creutzfeldt-Jakob disease. From the Bristol Institute for Transfusion Sciences, National Blood Service, Bristol; the Institute for Animal Health, Compton; and the Scottish National Blood Transfusion Service, the National Creutzfeldt-Jakob Disease Surveillance Unit, and the Roslin Institute, Edinburgh, UK. Address reprint requests to: David J. Anstee, Bristol Institute for Transfusion Sciences, Southmead, Bristol BS10 5ND, UK; e-mail: david.anstee@nbs.nhs.uk. This work was funded by a grant from the Department of Health and National Institute for Health Research (NIHR) England (DH 007/0078). Received for publication December 22, 2007; revision received February 27, 2008, and accepted March 1, 2008. doi: 10.1111/j.1537-2995.2008.01759.x TRANSFUSION 2008;48:1616-1626. 1616 TRANSFUSION Volume 48, August 2008