P H Pfeifer1, M S Kawahara, T E Hugli. 1. The Futhan/EDTA tubes are produced by Terumo Europe and can be purchased from PerSeptive Biosystems, 500 Old Connecticut Path, Framingham, MA 01701, USA.
Abstract
BACKGROUND: Ongoing in vitro complement (C) activation in citrate or EDTA plasma has prevented an accurate analysis of C-activation products generated in vivo. The aim of this study was to characterize handling and storage conditions required to prevent in vitro C activation in blood and plasma samples collected with Futhan/EDTA. METHODS: Biotrak(TM) RIAs were used to quantitatively measure C3a and C4a in blood and/or plasma samples from healthy individuals (controls) and from liver transplant patients. Blood samples were routinely drawn into either EDTA (1 g/L) tubes or into tubes containing both EDTA (1 g/L) and Futhan (0.1 g/L) and immediately centrifuged at 2000g for 15 min at 4 degrees C. RESULTS: In controls, C4a, but not C3a, in fresh samples (time 0) was higher in EDTA plasma than in Futhan/EDTA plasma (n = 20; P = 0.002). Futhan/EDTA prevented C3a and C4a generation in blood and plasma samples held at room temperature (22-23 degrees C) for 1 h and in plasma held for 24 h at 4 degrees C or -70 degrees C. The mean C3a concentration (1.76 mg/L; n = 19) at time 0 in EDTA plasma samples from liver transplant patients was significantly higher than for controls (0.34 mg/L; n = 11). In these patients, the mean C3a in EDTA samples increased to 13.8 mg/L after 60 min at room temperature, but there was no change in the C3a concentration of an EDTA plasma from a control. In the patients, C3a concentrations were lower in Futhan/EDTA plasma than in EDTA at time 0 and after 60 min at room temperature (1.40 and 2.02 mg/L, respectively). The mean patient C4a was 4.02 mg/L in EDTA plasma at time 0 vs 0.24 mg/L for controls; it increased to 16.9 mg/L after 60 min at room temperature compared with 0.76 mg/L for controls. The mean patient C4a was 0.83 mg/L in Futhan/EDTA plasma at time 0 vs 0.1 mg/L for controls. Neither patient nor control C4a concentrations increased vs time in Futhan/EDTA. CONCLUSION: The combination of Futhan (0.1 g/L) and EDTA (1 g/L) eliminates in vitro C activation.
BACKGROUND: Ongoing in vitro complement (C) activation in citrate or EDTA plasma has prevented an accurate analysis of C-activation products generated in vivo. The aim of this study was to characterize handling and storage conditions required to prevent in vitro C activation in blood and plasma samples collected with Futhan/EDTA. METHODS: Biotrak(TM) RIAs were used to quantitatively measure C3a and C4a in blood and/or plasma samples from healthy individuals (controls) and from liver transplant patients. Blood samples were routinely drawn into either EDTA (1 g/L) tubes or into tubes containing both EDTA (1 g/L) and Futhan (0.1 g/L) and immediately centrifuged at 2000g for 15 min at 4 degrees C. RESULTS: In controls, C4a, but not C3a, in fresh samples (time 0) was higher in EDTA plasma than in Futhan/EDTA plasma (n = 20; P = 0.002). Futhan/EDTA prevented C3a and C4a generation in blood and plasma samples held at room temperature (22-23 degrees C) for 1 h and in plasma held for 24 h at 4 degrees C or -70 degrees C. The mean C3a concentration (1.76 mg/L; n = 19) at time 0 in EDTA plasma samples from liver transplant patients was significantly higher than for controls (0.34 mg/L; n = 11). In these patients, the mean C3a in EDTA samples increased to 13.8 mg/L after 60 min at room temperature, but there was no change in the C3a concentration of an EDTA plasma from a control. In the patients, C3a concentrations were lower in Futhan/EDTA plasma than in EDTA at time 0 and after 60 min at room temperature (1.40 and 2.02 mg/L, respectively). The mean patientC4a was 4.02 mg/L in EDTA plasma at time 0 vs 0.24 mg/L for controls; it increased to 16.9 mg/L after 60 min at room temperature compared with 0.76 mg/L for controls. The mean patientC4a was 0.83 mg/L in Futhan/EDTA plasma at time 0 vs 0.1 mg/L for controls. Neither patient nor control C4a concentrations increased vs time in Futhan/EDTA. CONCLUSION: The combination of Futhan (0.1 g/L) and EDTA (1 g/L) eliminates in vitro C activation.
Authors: Laura R La Bonte; Betsy Dokken; Grace Davis-Gorman; Gregory L Stahl; Paul F McDonagh Journal: Diab Vasc Dis Res Date: 2009-07 Impact factor: 3.291
Authors: Eveline Y Wu; Elizabeth A McInnis; Sonia Boyer-Suavet; Carmen E Mendoza; Lydia T Aybar; Kristin B Kennedy; Caroline J Poulton; Candace D Henderson; Yichun Hu; Susan L Hogan; Peiqi Hu; Hong Xiao; Patrick H Nachman; J Charles Jennette; Ronald J Falk; Donna O Bunch Journal: Arthritis Rheumatol Date: 2019-10-08 Impact factor: 10.995