title: mRNA levels of CD31, CD144, CD146 and von Willebrand factor do not serve as surrogate markers for circulating endothelial cells.
abstract: Circulating endothelial cells (CEC) are considered a promising marker to determine the extent of vascular damage. However, currently available and validated CEC enumeration assays are laborious, time consuming and costly, which limits their clinical utility. Here, we evaluated the feasibility of quantifying mRNA levels of the endothelium-associated markers CD31, CD144, CD146 and von Willebrand factor (vWf) in peripheral blood (PB) of healthy donors, patients, and human umbilical veins by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and their use as surrogate markers for CEC. Whole blood samples and CD146+ cell-enriched fractions were assessed for mRNA and protein expression of CD31, CD144, CD146 and vWf by RT-PCR and flow cytometry, respectively. We showed the feasibility to detect endothelial mRNA isolated from HUVEC numbers as low as 10. However, no endothelial mRNA could be measure in whole blood samples, and only low levels of CD31 and CD146 mRNA were detected in suspensions of isolated CEC with numbers up to 4,450 CEC per sample. We conclude that mRNA levels of CD31, CD144, CD146 and vWf in whole blood as detected by real time RT-PCR cannot be used as biomarkers for end-stage endothelial cells such as CEC.
authors.affiliation: Laboratory of Translational Tumorimmunolgy, Department of Medical Oncology, Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, The Netherlands.
authors.forename: Michiel H
authors.initials: MH
authors.lastname: Strijbos
authors.forename: Brigitte A
authors.initials: BA
authors.lastname: van Krimpen
authors.forename: Reno
authors.initials: R
authors.lastname: Debets
authors.forename: Jaco
authors.initials: J
authors.lastname: Kraan
authors.forename: Stefan
authors.initials: S
authors.lastname: Sleijfer
authors.forename: Jan Willem
authors.initials: JW
authors.lastname: Gratama
authors.forename: Cor H J
authors.initials: CH
authors.lastname: Lamers
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000235:genetics*; D017209:Apoptosis; D015415:Biomarkers / Q000097:blood; D051929:CD146 Antigen / Q000235:genetics; D015820:Cadherins / Q000235:genetics*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D005240:Feasibility Studies; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D018189:Immunomagnetic Separation; D008297:Male; D008875:Middle Aged; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000235:genetics*; D012333:RNA, Messenger / Q000097:blood*; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000378:metabolism*; D014841:von Willebrand Factor / Q000235:genetics*; D000099152:Cadherin 5
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; D051929:CD146 Antigen; D015820:Cadherins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D014841:von Willebrand Factor; D000099152:Cadherin 5; C497902:MCAM protein, human