Adipose-derived stem cells and adipose-derived stem cell-conditioned medium modulate in situ imbalance between collagen I- and collagen V-mediated IL-17 immune response recovering bleomycin pulmonary fibrosis
Renato Gonçalves Felix1, Ana Livia Carvalho Bovolato1, Ondina Silvia Cotrim1, Patricia dos Santos Leão2, Sabrina Setembre Batah2, Márjorie de Assis Golim1, Ana Paula Velosa3, Walcy Teodoro3, Vanessa Martins4, Fernanda Ferreira Cruz5, Elenice Deffune1, Alexandre Todorovic Fabro2 and Vera Luiza Capelozzi4
1Botucatu Medical School, São Paulo State University, 2Department of Pathology, Ribeirão Preto Medical School, 3Rheumatology Division, 4Department of Pathology, Faculty of Medicine, University of São Paulo, São Paulo and 5Laboratory of Pulmonary Investigation, Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Brazil
Offprint requests to: Prof Vera Luiza Capelozzi, Department of Pathology, Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo 455, sala 1143, Zip code 01246-903, São Paulo, SP, Brazil. e-mail: vera.capelozzi@fm.usp.br
Summary. The immunogenic collagen V (Col V) and the proinflammatory cytokine interleukin (IL)-17 have been implicated in the pathogenesis of multiple autoimmune diseases. Col V is also up-regulated during adipogenesis and can stimulate adipocyte differentiation in vitro. Conditioned medium (CM) generated from adipose-derived mesenchymal stem cells (MSCs) reduces bleomycin (BLM)-induced lung injury in rats, suggesting a crucial role in situ of immunomodulatory factors secreted by MSCs in these beneficial effects. In the present work, we investigated this hypothesis, analyzing levels of plasma inflammatory mediators and inflammatory and fibrotic mediators in the lung tissue of BLM-injured rats after treatment with MSCs and CM. Pulmonary fibrosis was intratracheally induced by BLM. After 10 days, BLM animals were further randomized into subgroups receiving saline, MSCs, or CM intravenously. On days 14 and 21, the animals were euthanized, and the lungs were examined through protein expression of nitric oxide synthase (NOS), IL-17, transforming growth factor-β (TGF-β), vascular endothelial growth factor, endothelin-1, and the immunogenic Col V through histological quantitative evaluation and plasma levels of fibrinogen, Von Willebrand factor, and platelet-derived growth factor (PDGF). Rats that had been injected with MSCs and CM showed a significant increase in weight and significant improvements at 14 and 21 days after intravenous injection at both time points of analysis of plasma fibrinogen, PDGF, and Von Willebrand factor and NOS-2 expression, supporting an early anti-inflammatory action, thus reducing TGF-β and collagen I fibers. In contrast, intravenous injection of CM was able to significantly increase the deposition of Col V fibers and IL-17 on both day 14 and day 21 as compared with the amount observed in rats from the BLM group and MSC groups. In conclusion, this study reinforces previous observations on the therapeutic properties of MSCs and CM and is the first report to demonstrate the association of its actions with immunomodulatory biomarkers on lung tissue. We concluded that adipose-derived stem cells and adipose-derived stem cells-CM modulate an in situ imbalance between collagen I- and Col V-mediated IL-17 immune response, emerging as a promising therapeutic option for recovering from BLM pulmonary fibrosis. Histol Histopathol 35, 289-301 (2020)
Key words: Adipose-derived mesenchymal stem cells, Conditioned medium, Collagen fibers, Growth factors, Cytokines, IL-17, Bleomycin, Collagen V, Electron microscopy
DOI: 10.14670/HH-18-152