PT  - JOURNAL ARTICLE
AU  - Bhola Kumar Dahal
AU  - Djuro Kosanovic
AU  - Josef Messinger
AU  - Yvan Fischer
AU  - Katrin Hoffmann
AU  - Jochen Antel
AU  - Bettina Husen
AU  - Nina Hanke
AU  - Stephanie Mayet
AU  - Hossein Ardeschir Ghofrani
AU  - Norbert Weissmann
AU  - Friedrich Grimminger
AU  - Werner Seeger
AU  - Ralph Schermuly
TI  - Role of mast cells and chymase in pulmonary vascular remodeling
DP  - 2011 Sep 01
TA  - European Respiratory Journal
PG  - p1524
VI  - 38
IP  - Suppl 55
4099  - http://erj.ersjournals.com/content/38/Suppl_55/p1524.short
4100  - http://erj.ersjournals.com/content/38/Suppl_55/p1524.full
SO  - Eur Respir J2011 Sep 01; 38
AB  - Rationale: Mast cells (MCs) are implicated in chronic inflammation and tissue remodeling. However, a systematic investigation of pulmonary MCs/MC chymase is yet missing in idiopathic pulmonary arterial hypertension (IPAH) and chronic obstructive pulmonary disease (COPD).Methods: Lung tissues obtained from donors, and IPAH and COPD patients undergoing lung transplantation were formalin-fixed and paraffin-embedded, followed by toluidine blue (TB) staining for MCs and immunostaining for MC chymase. Total and perivascular MCs were determined by counting MCs under light microscope equipped with computerized morphometric system. Perivascular MCs were categorized as granulated and degranulated and an index of granulation (IOG) [(number of granulated/degranulated MCs)] was determined.Results: Pulmonary MCs were prevalent in IPAH and COPD patients; furthermore, perivascular MC count was significantly increased in the resistance vessels of patients (p<0.05 vs donors). Notably, the IOG was decreased by about 8 and 5 folds in IPAH and COPD patients, respectively (vs donors). Chymase-positive MCs were increased by 16 and 10 folds in IPAH and COPD patients, respectively (vs donors). The perivascular chymase-positive MCs were significantly increased in IPAH and COPD patients (p<0.05 vs donors). Interestingly, the chymase-positive MC subpopulations were about 42% and 48% of the MCs in IPAH and COPD patients, respectively; whereas it was 10% in donors.Conclusion: The chymase released from activated perivascular MCs may potentially contribute to the pulmonary vascular remodeling in IPAH and COPD. Future studies are essential to substantiate the findings and to elucidate underlying pathomechanisms.