Background:Connective tissue disease-associated interstitial lung disease (CTD-ILD) is a class of refractory diseases.Non-specific treatment with hormone and immunosuppressive agents is mostly used at present, but the effect is limited and the long-term survival rate is not improved [1],while anti-fibrosis treatments (such as Pirfenidone and Nintedanib) have only recently been approved, the long-term efficacy is still unknown.Tofacitinib(TOFA), a JAK inhibitor, has recently been used to treat patients with severe dermatomyositis related interstitial pulmonary disease, with significantly improved survival rate [2-4].A basic study showed that TOFA improved interstitial pulmonary disease in mice by promoting the proliferation of myelogenic inhibitory cells [5].However, whether TOFA can affect the migration and invasion of human lung fibroblasts and further research to reveal the mechanism of its inhibition of pulmonary fibrosis has not been reported.Objectives:To investigate the anti - fibrosis effect of TOFA in CTD-ILD.Methods:Cell migration and invasion AssaysHLFs were incubated with TOFA for 72h, followed by TGF- β1 for 24h.DMEM serum-free medium was used to determine the cell density to 5. 0 × 107/L, 600 uL medium containing 10% fetal bovine serum was added to the lower compartment of Transwell chamber, and 200 uL cell suspension was added to the upper compartment.Incubate in incubator for 12 h.After fixation, staining and sealing, the cells were observed and counted under a microscope. At least 5 random field transmembrane cells were counted in each hole, and the mean value was taken.For the invasion assays, Transwell chamber coated with matrigel was used, and the cell incubation time was 16 h.Results:1. Effect of TOFA on HLFs migration function (Figure 1)Figure 1.Effect of TOFA on HLFs migration function(×200).Mean ± SEM. n = 5.The number of cells passing through the biofilm in the three groups was counted.It can be seen that TGF-β1 group significantly increased compared with control group (*P < 0.0001), and TOFA group significantly decreased compared with TGF- β1 group (#P < 0.0001), suggesting that TOFA can significantly inhibit TGF-β1- induced HLFs migration.2. Effect of TOFA on HLFs invasion function (Figure 2)Figure 2.Effect of TOFA on HLFs invasion function(×200).Mean ± SEM. n = 5.The number of cells passing through the matrigel in the three groups was counted.It can be seen that TGF-β1 group was significantly higher than the control group (*P < 0.0001), and TOFA group was significantly lower than TGF-β1 group(#P < 0.001), suggesting that TOFA can significantly inhibit the invasion function of HLFs induced by TGF-β1.Conclusion:TOFA can effectively inhibit the function of HLFs migration and invasion. Although further studies are needed to elucidate the mechanism by which TOFA inhibit the function of HLFs migration and invasion, our study suggests that TOFA has a potential therapeutic effect for CTD-ILD.References:[1]Aparicio, I.J. and J.S. Lee, Connective Tissue Disease-Associated Interstitial Lung Diseases: Unresolved Issues. Semin Respir Crit Care Med, 2016. 37(3): p. 468-76.[2]Kato, M., et al., Successful Treatment for Refractory Interstitial Lung Disease and Pneumomediastinum With Multidisciplinary Therapy Including Tofacitinib in a Patient With Anti-MDA5 Antibody-Positive Dermatomyositis. J Clin Rheumatol, 2019.[3]Kurasawa, K., et al., Tofacitinib for refractory interstitial lung diseases in anti-melanoma differentiation-associated 5 gene antibody-positive dermatomyositis. Rheumatology (Oxford), 2018. 57(12): p. 2114-2119.[4]Chen, Z., X. Wang, and S. Ye, Tofacitinib in Amyopathic Dermatomyositis-Associated Interstitial Lung Disease. N Engl J Med, 2019. 381(3): p. 291-293.[5]Sendo, S., et al., Tofacitinib facilitates the expansion of myeloid-derived suppressor cells and ameliorates interstitial lung disease in SKG mice. Arthritis Res Ther, 2019. 21(1): p. 184Disclosure of Interests:None declared
P169 Comparison of Work of Breathing: Heart failure versus Interstitial Lung Disease
