title: The influence of the blood handling process on the measurement of circulating TGF-β1.
abstract: In order to evaluate the impact of blood sample handling processes on circulating TGF-β1 levels, blood specimens were obtained from 13 healthy volunteers using different handling processes (kept at room temperature (RT) or on ice before centrifugation, using different centrifugal forces). TGF-β1 levels were measured using an enzyme-linked immunosorbent assay. A paired-T test was used for statistical analysis. The TGF-β1 level in on-ice serum was significantly lower than that in room-temperature serum (P&#60;0.001), and both were significantly higher than that found in on-ice plasma (P&#60;0.001). Compared with on-ice plasma samples, the longer the samples were kept at RT, the higher the levels of TGF-β1 in plasma (P=0.268, 0.040, and 0.0015 for 5 min, 30 min, and 60 min in RT, respectively). Compared with plasma centrifuged at 2,500×g for 30 min, the TGF-β1 levels were much lower than those found in plasma centrifuged at 1,200×g for 10 min (P=0.003); and a double centrifugation before TGF-β1 detection, significantly decreased the level (P&#60;0.001). It is suggested that the optimal sampling conditions for the detection of TGF-β1 should be plasma prepared on ice and spun down at a higher centrifugal force.
authors.affiliation: Department of Radiation Oncology, Peking Union Medical College & Chinese Academy of Medical Science, Cancer Institute and Hospital, Beijing, China.
authors.forename: Lujun
authors.initials: L
authors.lastname: Zhao
authors.forename: Luhua
authors.initials: L
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Ji
authors.forename: Mingfang
authors.initials: M
authors.lastname: Lei
authors.forename: Weizhi
authors.initials: W
authors.lastname: Yang
authors.forename: Feng-Ming
authors.initials: FM
authors.lastname: Kong
mesh_terms: D000328:Adult; D001793:Blood Preservation / Q000379:methods; D002498:Centrifugation; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D010949:Plasma / Q000737:chemistry; D015203:Reproducibility of Results; D044967:Serum / Q000737:chemistry; D013048:Specimen Handling / Q000379:methods*; D013696:Temperature; D013997:Time Factors; D053773:Transforming Growth Factor beta1 / Q000097:blood*
chemical_list: D053773:Transforming Growth Factor beta1