The lower airways microbiota and antimicrobial peptides indicate dysbiosis in sarcoidosis

Rationale: The role of the pulmonary microbiome in sarcoidosis is unknown.Objectives: The objectives of the current study was to: 1) Examine whether the pulmonary fungal and bacterial microbiota differed in patients with sarcoidosis compared with controls. 2) Examine whether there was an association between the microbiota and levels of the antimicrobial peptides (AMPs) in protected bronchoalveolar lavage (PBAL), indicating an interaction with the innate immune response.Methods: 35 sarcoidosis patients and 35 healthy controls underwent bronchoscopy and were sampled with oral wash (OW), protected BAL (PBAL) and left protected sterile brushes (LPSB).

The fungal ITS1 region and the V3V4 region of the bacterial 16SrDNA gene were sequenced. Bioinformatic analyses were performed with QIIME 2. The AMPs secretory leucocyte protease inhibitor (SLPI) and human beta defensins 1 and 2 (hBD-1 & hBD-2), were measured in PBAL by enzyme linked immunosorbent assay (ELISA).Measurements and Main Results: Aspergillus dominated the PBAL samples in sarcoidosis.