Changes in the serum level of matrix metalloproteinases and surfactant proteins in patients with hypersensitivity pneumonitis

The most studied biomarkers of progressive pulmonary fibrosis (PPF) are matrix metalloproteinases (MMP) types 1, 7 and 9 and surfactant proteins A and D (SP-A and SP-D). The aim was to study the levels of MMP-1, MMP-7, MMP-9, SP-A and SP-D in the context of diagnosis of idiopathic pulmonary fibrosis (IPF) and hypersensitivity pneumonitis (HP) and the relationship of these indicators with the PPF criteria. Methods . The study included 65 patients with ILD. Analysis of computed tomography (CT) scans, spirometry, and lung diffusion capacity data were performed. PPF was established based on the diagnostic criteria of the American Thoracic Society (2022). Quantitative determination of serum SP-A levels was performed using Cloud-Clone Corp. kits. (China), SP-D and MMP-7 levels using RDS kits (USA), MMP-1 and MMP-9 levels using RayBiotech kits (USA) on the Hydro Flex enzyme immunoassay (TECAN, Austria). Statistical data processing was performed using Statistica 10.0 software. Results. A relationship between elevated MMP-7 and SP-D levels in HP and PPF criteria was found. No statistically significant differences were found between MMP-7 and SP-D levels in IPF and HP with PPF (9.03 ± 3.1 and 8.47 ± 2.61 ng/ml, respectively; p = 0.42), as well as SP-D (34.51 ± 6.12 ng/ml in IPF and 33.22 ± 8.91 ng/ml in HP with PPF; p = 0.45). Negative correlation was noted between elevated levels of SP-D and MMP-7 with FVC and DLCO during the year. Conclusion. An increase in the levels of MMP-7 and SP-D in the blood serum allows us to consider these indicators for the diagnosis of PPF in HP.