Introduction: IPF is characterized by aberrant extracellular matrix deposition, with altered collagen fibril organization. Collagen type XIV (COL14) facilitates 3D organization of collagen type I fibrils; whether abnormalities in COL14 are present in IPF lungs is hitherto unknown. In this study, we aimed to examine how much collagen type XIV was detected in the lung tissue of patients with IPF at protein level.

Methods: Controls (Never-smoker (n=9), ex-smoker (n=9)) and IPF (n=12) lung tissues were sectioned and stained for COL14. Scanned images were analysed as whole tissue or compartments: airway wall, bronchial epithelium and parenchyma to assess the location of deposition of collagen type XIV. The relative tissue area positive for COL14 was calculated using ImageJ.

Results: COL14 was detected in parenchyma, airway wall and bronchial epithelium in control lungs. Patients with IPF had a lower percentage area of tissue positive for COL14 (Figure 1), which was significantly lower than in controls in whole tissue and all compartments. The COL14 in ex- and never smoker control groups did not differ in any of the tissue regions.

Discussion: Our results illustrate lower proportional levels of COL14 in IPF lungs compared to both never- and ex-smokers. These results imply a lack of contribution of COL14 in IPF, which might in turn contribute to disrupted structural organization of collagen fibres.