title: The influence of different anticoagulants and time-delayed sample processing and measurements on human monocyte subset and monocyte-platelet aggregate analyses.
abstract: Measuring human monocyte subsets (CD14++CD16-, CD14++CD16+, and CD14 + CD16++) and subset-specific monocyte-platelet aggregates (MPA) is vulnerable to analytical bias due to unavailability of a standardized methodology. We aimed to address this issue by focusing on the impacts of time-delayed sample processing and measurement between two commonly used anticoagulants.
  
  
  
  Ethylenediaminetetraacetic acid (EDTA)- and sodium citrate (SC)-anticoagulated blood samples from 12 healthy donors were subject to either delayed (2-h delay, kept at 4°C) or immediate processing (without fixation) before four-color flow cytometry (FCM) analysis.
  
  
  
  In SC-anticoagulated samples, a 2-h delay in sample processing contributed to a significant decrease in CD14++CD16- monocyte percent and a reciprocal increase in CD14++CD16+ monocytes, as well as increases in all three subset-specific MPA. Similar slight, but non-significant changes were observed in EDTA-treated samples. In samples processed immediately and stored at 4°C, delayed measurement at 0, 1, 3, and 5 h after processing led to a time-dependent decrease in CD14++CD16- monocyte percent and a reciprocal increase in CD14++CD16+ subset in SC-treated, but not in EDTA-treated, samples. Moreover, a time-dependent increase in all three subset-specific MPA was observed in SC-treated samples, which, to a lesser extent, was only observed in CD14++CD16+ MPA in EDTA-treated samples after storage at 4°C for 3-5 h after processing.
  
  
  
  We recommend EDTA for anticoagulation. Additionally, sample should be stored at 4°C and processing and measuring should be performed within 2 h after harvest and 3 h after processing, respectively. © 2016 International Clinical Cytometry Society.
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.|Department of Respiratory and Critical Care Medicine, Pingjin Hospital, Tianjin, China.
authors: Wen-Jie
authors: WJ
authors: Ji
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Rui-Yi
authors: RY
authors: Lu
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Jun-Xiang
authors: JX
authors: Liu
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Yong-Qiang
authors: YQ
authors: Ma
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Shan
authors: S
authors: Zeng
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Rui
authors: R
authors: Shi
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Ji-Hong
authors: JH
authors: Zhao
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Shao-Bo
authors: SB
authors: Chen
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Xin
authors: X
authors: Zhou
authors: Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China.
authors: Yu-Ming
authors: YM
authors: Li
mesh_terms: D000925:Anticoagulants / Q000494:pharmacology*; D001792:Blood Platelets / Q000166:cytology* / Q000187:drug effects*; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000378:metabolism; D009000:Monocytes / Q000166:cytology* / Q000187:drug effects*; D017452:Receptors, IgG / Q000378:metabolism; D013997:Time Factors
chemical_list: D000925:Anticoagulants; D018950:Lipopolysaccharide Receptors; D017452:Receptors, IgG
keywords: anticoagulation; flow cytometry; monocyte subsets; monocyte-platelet aggregates/platelet-monocyte aggregates; sample preparation