title: PAR-2, IL-4R, TGF-β and TNF-α in bronchoalveolar lavage distinguishes extrinsic allergic alveolitis from sarcoidosis.
abstract: Sarcoidosis (SARC) and extrinsic allergic alveolitis (EAA) share certain markers, making a differential diagnosis difficult even with histopathological investigation. In lung tissue, proteinase-activated receptor-2 (PAR-2) is primarily investigated with regard to epithelial and inflammatory perspectives. Varying levels of certain chemokines can be a useful tool for distinguishing EAA and SARC. Thus, in the present study, differences in the levels of transforming growth factor (TGF)-β1, tumor necrosis factor (TNF)-α, interleukin-4 receptor (IL-4R) and PAR-2 in bronchoalveolar lavage fluid (BALF) were compared, using an ELISA method, between 14 patients with EAA and six patients with SARC. Statistically significant higher levels of IL-4R, PAR-2 and the PAR-2/TGF-β1 and PAR-2/TNF-α ratios were observed in EAA patients as compared with SARC patients. Furthermore, the ratios of TNF-α/total protein, TGF-β1/PAR-2 and TNF-α/PAR-2 were significantly lower in EAA patients than in SARC patients. The results indicated a higher detection of PAR-2 in EAA samples in association with TNF-α and TGF-β levels. As EAA and PAR-2 in parallel belong to the Th2-mediated pathway, the results significantly indicated an association between this receptor and etiology. In addition, the results indicated that SARC is predominantly a granulomatous inflammatory disease, thus, higher levels of TNF-α are observed. Therefore, the detection of PAR-2 and investigated chemokines in BALF may serve as a useful tool in the differential diagnosis between EAA and SARC.
authors.affiliation: Department of Pathology and Molecular Medicine, Thomayer Hospital, Prague 140 59, Czech Republic ; Department of Pathology, Third Faculty of Medicine, Charles University, Prague 100 00, Czech Republic.
authors.forename: Radoslav
authors.initials: R
authors.lastname: Matěj
authors.affiliation: Department of Pathology and Molecular Medicine, Thomayer Hospital, Prague 140 59, Czech Republic.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Smětáková
authors.affiliation: Department of Respiratory Medicine, Thomayer Hospital, Prague 140 59, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Vašáková
authors.affiliation: Department of Pathology and Molecular Medicine, Thomayer Hospital, Prague 140 59, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Nováková
authors.affiliation: Department of Respiratory Medicine, Thomayer Hospital, Prague 140 59, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Sterclová
authors.affiliation: Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Prague 115 19, Czech Republic.
authors.forename: Jaromír
authors.initials: J
authors.lastname: Kukal
authors.affiliation: Department of Pathology and Molecular Medicine, Thomayer Hospital, Prague 140 59, Czech Republic ; Department No. 75, Institute of Physiology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Olejár
keywords: extrinsic allergic alveolitis; interleukin-4 receptor; proteinase-activated receptor-2; sarcoidosis; transforming growth factor-β; tumor necrosis factor-α