Experimental Modeling Of Lung Involvement Due To Systemic Sclerosis

Background: Lung injury is a satellite of a number of autoimmune pathologies. This problem is especially urgent in systemic sclerosis (SSc). Aim: To determine changes in the morphological structure of lung tissue due to SSc in an experimental study. Methods: For SSc induction the hypochlorous model [Servettaz A, et al. The Journal of Immunology, 2009 182(9), 5855-5864.] was used, but with somе modifications. Into the study were involved 30 Wistar rats (220-240g) who underwent three times a week subcutaneous administration of 0.5ml of 5% sodium hypochlorite (NaClO) solution with active chlorine concentration of 190 g/dm3 for 6 weeks in a row and control group of 20 rats. After 8 weeks they were sacrificed, lung tissue specimens were obtained and stained with hematoxylin and eosin (H&E). Magnification was x200 (Leica DM750). Results: The biopsy of lung specimens reviled the typical for SSc remodeling process in parenchyma and microcirculatory bed of the alveolar wall. Vasculitis was characterized by destructive-proliferative processes in the vessels wall with fibrinoid necrosis and thrombosis of the affected vessels. Interstitial pneumonitis was characterized by productive and sclerotic changes of the interalveolar septum, their infiltration by the lymphoid and plasma cells with partial obliteration of the alveoli. The Ashcroft score was significantly higher in the experimental group (3.7±0.6) comparing to control animals (0.6±0.1) (p<0,05). Conclusions: The NaСlO model reproduces the typical sclerodermic lesions in the lung parenchyma and could be used for further investigation of lung involvement peculiarities within this autoimmune pathology.