title: Dynamic changes in lymphocyte GRK2 levels in cardiac transplant patients: a biomarker for left ventricular function.
abstract: G protein-coupled receptor kinase 2 (GRK2), which is upregulated in the failing human myocardium, appears to have a role in heart failure (HF) pathogenesis. In peripheral lymphocytes, GRK2 expression has been shown to reflect myocardial levels. This study represents an attempt to define the role for GRK2 as a potential biomarker of left ventricular function in HF patients. We obtained blood from 24 HF patients before and after heart transplantation and followed them for up to 1 year, also recording hemodynamic data and histological results from endomyocardial biopsies. We determined blood GRK2 protein by Western blotting and enzyme-linked immunosorbent assay. GRK2 levels were obtained before transplant and at first posttransplant biopsy. GRK2 levels significantly declined after transplant and remained low over the course of the study period. After transplantation, we found that blood GRK2 significantly dropped and remained low consistent with improved cardiac function in the transplanted heart. Blood GRK2 has potential as a biomarker for myocardial function in end-stage HF.
authors.affiliation: Department of Medicine, Division of Cardiology, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Raphael E
authors.initials: RE
authors.lastname: Bonita
authors.forename: Philip W
authors.initials: PW
authors.lastname: Raake
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Otis
authors.forename: J Kurt
authors.initials: JK
authors.lastname: Chuprun
authors.forename: Talya
authors.initials: T
authors.lastname: Spivack
authors.forename: Abhijit
authors.initials: A
authors.lastname: Dasgupta
authors.forename: David J
authors.initials: DJ
authors.lastname: Whellan
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Mather
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Koch
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism*; D015153:Blotting, Western; D003600:Cytosol / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D054769:G-Protein-Coupled Receptor Kinase 2 / Q000378:metabolism*; D006333:Heart Failure / Q000097:blood / Q000628:therapy*; D016027:Heart Transplantation / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D008214:Lymphocytes / Q000166:cytology; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D016277:Ventricular Function, Left
chemical_list: D015415:Biomarkers; C496567:GRK2 protein, human; D054769:G-Protein-Coupled Receptor Kinase 2