title: CXCL13 in idiopathic pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.
abstract: BACKGROUND
  Chemokine CXC ligand 13 (CXCL13) has been implicated in perivascular inflammation and pulmonary vascular remodeling in patients with idiopathic pulmonary artery hypertension (IPAH). We wondered whether CXCL13 may also play a role in chronic thromboembolic pulmonary hypertension (CTEPH) and whether serum levels of CXCL13 might serve as biomarkers in these conditions.
  
  
  METHODS
  Lung tissue from patients with IPAH or CTEPH was immunostained for CXCL13. Serum samples were obtained from patients with IPAH (n = 42) or CTEPH (n = 50) and from healthy controls (n = 13). Serum CXCL13 concentrations were measured by enzyme-linked immunosorbent assay technology and were evaluated for associations with markers of disease severity and survival.
  
  
  RESULTS
  CXCL13 was expressed in pulmonary vascular lesions and lymphocytes of patients with IPAH and inoperable CTEPH, respectively. Serum CXCL13 was elevated in patients compared to healthy controls [median, interquartile range, 83 (55,114) pg/ml versus 40 (28, 48) pg/ml; p < 0.001]. Serum CXCL13 showed only weak and inconsistent correlations with markers of inflammation or disease severity. In both populations, patients with serum CXCL13 above the median of the respective groups did not have a higher risk of death than patients with lower serum CXCL13.
  
  
  CONCLUSIONS
  CXCL13 was overexpressed in pulmonary vascular lesions of patients with IPAH and CTEPH, and increased serum concentrations were found in patients with IPAH and CTEPH, suggesting a potential pathogenic role of CXCL13 in both diseases. However, given the weak associations between serum CXCL13 and markers of disease severity and outcome, CXCL13 is unlikely to become a promising biomarker in these patient populations.
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany. Olsson.karen@mh-hannover.de.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Olsson
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany. Olle.sandra@yahoo.com.
authors.forename: Sandra
authors.initials: S
authors.lastname: Olle
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany. Fuge.jan@mh-hannover.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Fuge
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany. Welte.tobias@mh-hannover.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Welte
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany. Hoeper.marius@mh-hannover.de.
authors.forename: Marius M
authors.initials: MM
authors.lastname: Hoeper
authors.affiliation: Department of Pediatric Nephrology, Hannover Medical School, Hannover, Germany. Lerch.christian@mh-hannover.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Lerch
authors.affiliation: Department of Pathology, Hannover Medical School, Hannover, Germany. Maegel.lavinia@mh-hannover.de.
authors.forename: Lavinia
authors.initials: L
authors.lastname: Maegel
authors.affiliation: Department of Nephrology, Hannover Medical School, Hannover, Germany. Haller.hermann@mh-hannover.de.
authors.forename: Hermann
authors.initials: H
authors.lastname: Haller
authors.affiliation: Department of Pathology, Hannover Medical School, Hannover, Germany. Jonigk.danny@mh-hannover.de.
authors.forename: Danny
authors.initials: D
authors.lastname: Jonigk
authors.affiliation: Department of Nephrology, Hannover Medical School, Hannover, Germany. Schiffer.lena@mh-hannover.de.
authors.forename: Lena
authors.initials: L
authors.lastname: Schiffer
mesh_terms: D017677:Age Distribution; D000368:Aged; D015415:Biomarkers / Q000097:blood; D054382:Chemokine CXCL13 / Q000097:blood*; D002908:Chronic Disease; D065627:Familial Primary Pulmonary Hypertension / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011655:Pulmonary Embolism / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D015996:Survival Rate
chemical_list: D015415:Biomarkers; C110663:CXCL13 protein, human; D054382:Chemokine CXCL13