Evaluation of the technical performance of novel holotranscobalamin (holoTC) assays in a multicenter European demonstration project
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Anne L. Morkbak
Abstract
A commercially available holotranscobalamin (holo-TC) radioimmunoassay (RIA) (Axis-Shield, Dundee, Scotland) was evaluated in four laboratories and compared with a holoTC ELISA run in one laboratory. The performance of the holoTC RIA assay was comparable in three of the four participating laboratories. The results from these three laboratories, involving at least 20 initial runs of “low”, “medium” and “high” serum-based controls (mean holoTC concentrations 34, 60 and 110pmol/L, respectively) yielded an intra-laboratory imprecision of 6–10%. No systematic inter-laboratory deviations were observed on runs involving 72 patient samples (holoTC concentration range 10–160pmol/L). A fourth laboratory demonstrated higher assay imprecision for control samples and systematic deviation of results for the patient samples. Measurement of holoTC by ELISA showed an imprecision of 4–5%, and slightly higher mean values for the controls (mean holoTC concentrations 40, 70 and 114pmol/L, respectively). Comparable results were obtained for the patient samples. The long-term intra-laboratory imprecision was 12% for the holoTC RIA and 6% for the ELISA. In conclusion, it would be prudent to check the calibration and precision prior to starting to use these holoTC assays in research or clinical practice. The results obtained using the holoTC RIA were similar to those obtained using the holoTC ELISA assay.
References
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©2005 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Homocysteine research – where do we stand and where are we going?
- Hyperhomocysteinemia and arteriosclerosis: historical perspectives
- Homocysteine and heart failure: a review of investigations from the Framingham Heart Study
- Homocysteine and vascular disease in diabetes: a double hit?
- Reduced adenosine receptor stimulation as a pathogenic factor in hyperhomocysteinemia
- Effects of homocysteine on vascular and tissue adenosine: a stake in homocysteine pathogenicity?
- Anti-N-homocysteinylated protein autoantibodies and cardiovascular disease
- Carotid narrowing degree and plasma thiol levels in carotid endarterectomy patients
- Impairment of homocysteine metabolism in patients with retinal vascular occlusion and non-arteritic ischemic optic neuropathy
- Hyperhomocysteinaemia in chronic kidney disease: focus on transmethylation
- Hyperhomocysteinemia and macromolecule modifications in uremic patients
- Hyperhomocysteinemia and response of methionine cycle intermediates to vitamin treatment in renal patients
- Vitamin B12 deficiency is the dominant nutritional cause of hyperhomocysteinemia in a folic acid-fortified population
- Homocysteine, folic acid and vitamin B12 in relation to pre- and postnatal health aspects
- Evaluation of the technical performance of novel holotranscobalamin (holoTC) assays in a multicenter European demonstration project
- A laboratory algorithm with homocysteine as the primary parameter reduces the cost of investigation of folate and cobalamin deficiency
- Betaine: a key modulator of one-carbon metabolism and homocysteine status
- Molecular targeting by homocysteine: a mechanism for vascular pathogenesis
- Anti-inflammatory compound resveratrol suppresses homocysteine formation in stimulated human peripheral blood mononuclear cells in vitro
- Homocysteine in relation to cognitive performance in pathological and non-pathological conditions
- Homocysteine and B vitamins in mild cognitive impairment and dementia
- Homocysteine, type 2 diabetes mellitus, and cognitive performance: The Maine-Syracuse Study
- Plasma homocysteine levels in L-dopa-treated Parkinson's disease patients with cognitive dysfunctions
- Homocysteine – a newly recognised risk factor for osteoporosis
- Relation between homocysteine and biochemical bone turnover markers and bone mineral density in peri- and post-menopausal women
- Elevated levels of asymmetric dimethylarginine (ADMA) as a marker of cardiovascular disease and mortality
- Measurement of asymmetric dimethylarginine in plasma: methodological considerations and clinical relevance
- Concentrations of homocysteine, related metabolites and asymmetric dimethylarginine in preeclamptic women with poor nutritional status
- Asymmetric dimethylarginine, homocysteine and renal function – is there a relation?
- Interactions between folate and aging for carcinogenesis
- The potential cocarcinogenic effect of vitamin B12 deficiency
- The vegetarian lifestyle and DNA methylation
Articles in the same Issue
- Homocysteine research – where do we stand and where are we going?
- Hyperhomocysteinemia and arteriosclerosis: historical perspectives
- Homocysteine and heart failure: a review of investigations from the Framingham Heart Study
- Homocysteine and vascular disease in diabetes: a double hit?
- Reduced adenosine receptor stimulation as a pathogenic factor in hyperhomocysteinemia
- Effects of homocysteine on vascular and tissue adenosine: a stake in homocysteine pathogenicity?
- Anti-N-homocysteinylated protein autoantibodies and cardiovascular disease
- Carotid narrowing degree and plasma thiol levels in carotid endarterectomy patients
- Impairment of homocysteine metabolism in patients with retinal vascular occlusion and non-arteritic ischemic optic neuropathy
- Hyperhomocysteinaemia in chronic kidney disease: focus on transmethylation
- Hyperhomocysteinemia and macromolecule modifications in uremic patients
- Hyperhomocysteinemia and response of methionine cycle intermediates to vitamin treatment in renal patients
- Vitamin B12 deficiency is the dominant nutritional cause of hyperhomocysteinemia in a folic acid-fortified population
- Homocysteine, folic acid and vitamin B12 in relation to pre- and postnatal health aspects
- Evaluation of the technical performance of novel holotranscobalamin (holoTC) assays in a multicenter European demonstration project
- A laboratory algorithm with homocysteine as the primary parameter reduces the cost of investigation of folate and cobalamin deficiency
- Betaine: a key modulator of one-carbon metabolism and homocysteine status
- Molecular targeting by homocysteine: a mechanism for vascular pathogenesis
- Anti-inflammatory compound resveratrol suppresses homocysteine formation in stimulated human peripheral blood mononuclear cells in vitro
- Homocysteine in relation to cognitive performance in pathological and non-pathological conditions
- Homocysteine and B vitamins in mild cognitive impairment and dementia
- Homocysteine, type 2 diabetes mellitus, and cognitive performance: The Maine-Syracuse Study
- Plasma homocysteine levels in L-dopa-treated Parkinson's disease patients with cognitive dysfunctions
- Homocysteine – a newly recognised risk factor for osteoporosis
- Relation between homocysteine and biochemical bone turnover markers and bone mineral density in peri- and post-menopausal women
- Elevated levels of asymmetric dimethylarginine (ADMA) as a marker of cardiovascular disease and mortality
- Measurement of asymmetric dimethylarginine in plasma: methodological considerations and clinical relevance
- Concentrations of homocysteine, related metabolites and asymmetric dimethylarginine in preeclamptic women with poor nutritional status
- Asymmetric dimethylarginine, homocysteine and renal function – is there a relation?
- Interactions between folate and aging for carcinogenesis
- The potential cocarcinogenic effect of vitamin B12 deficiency
- The vegetarian lifestyle and DNA methylation
