C-Kit+ cells can modulate asthmatic condition via differentiation into pneumocyte-like cells and alteration of inflammatory responses via ERK/NF-ƙB pathway.

Objectives: The exact role of the progenitor cell types in the dynamic healing of asthmatic lungs is lacking. This investigation was proposed to evaluate the effect of intratracheally administered rat bone marrow-derived c-kit+ cells on ovalbumin-induced sensitized male rats. Materials and Methods: Forty rats were randomly divided into 4 groups; healthy rats received phosphate-buffered saline (PBS) (C); sensitized rats received PBS (S); PBS containing C-kit- cells (S+C-kit-); and PBS containing C-kit+ cells (S+C-kit+). After two weeks, circulatory CD4+/CD8+ T-cell counts and pulmonary ERK/NF-ƙB signaling pathway as well as the probability of cellular differentiation were assessed. Results: The results showed that transplanted C-Kit+ cells were engrafted into pulmonary tissue and differentiated into epithelial cells. C-Kit+ cells could increase the number of CD4+ cells in comparison with the S group (P<0.001); however, they diminished the level of CD8+ cells (P<0.01). Moreover, data demonstrated increased p-ERK/ERK ratio (P<0.001) and NF-ƙB level (P<0.05) in sensitized rats compared with the C group. The administration of C-kit+, but not C-Kit-, decreased p-ERK/ERK ratio and NF-ƙB level compared with those of the S group (P<0.05). Conclusion: The study revealed that C-Kit+ cells engrafted into pulmonary tissue reduced the NF-ƙB protein level and diminished p-ERK/ERK ratio, leading to suppression of inflammatory response in asthmatic lungs.

Systemic administration of c-Kit+ cells diminished pulmonary and vascular inflammation in rat model of chronic asthma.

BACKGROUND: To circumvent some pitfalls related to acute status, chronic model of asthma is conceived to be more suitable approach to guarantee the conditions which are similar to human pulmonary disease. Here, possible therapeutic mechanisms were monitored by which c-kit+ bone marrow cells can attenuate vascular inflammation in rat model of chronic asthma. RESULTS: Data revealed c-Kit+ cells could significantly reduce pathological injures in asthmatic rats via modulating the expression of IL-4, INF-γ, ICAM-1 and VCAM-1 in lung tissues and TNF-α, IL-1ß and NO levels in BALF (p < 0.001 to p < 0.05). Besides, c-Kit+ cells reduced increased levels of VCAM-1 evaluated by immunohistochemistry staining. In contrast to c-Kit+ cells, c-Kit- cells could not exert beneficial effects in the asthmatic conditions. CONCLUSION: Overall, we found that systemic administration of C-kit positive cells can diminish pulmonary and vascular inflammation of chronic asthmatic changes in a rat model. These cells are eligible to suppress inflammation and nitrosative stress in lung tissue coincides with the reduction of pathological changes. These data indicate that C-kit positive cells be used as an alternative cell source for the amelioration of asthmatic changes.

C-Kit+ progenitors restore rat asthmatic lung function by modulation of T-bet and GATA-3 expression.

NEW FINDINGS: What is the central question of this study? The aim of the experiment was to highlight the regenerative capacity of bone marrow Kit+ cells in the restoration of asthmatic pulmonary function in the rat model. What is the main finding and its importance? Data showed that these cells were recruited successfully to the asthmatic niche after intratracheal administration and accelerated the regeneration of asthmatic lungs by the modulation of inflammation via the control of Gata3 and Tbx21 expression, leading to decreased tracheal responsiveness to methacholine and reduction of pathological remodelling. ABSTRACT: Allergic asthma is a T helper (Th) 2 immunological disorder with consequential uncontrolled inflammatory responses. There is an increasing demand to use new methods for the treatment of asthma based on modulation of the Th2-to-Th1 ratio in favour of the Th1 population. Accordingly, we decided to evaluate the effects of intratracheal administration of Kit+ bone marrow cells on tracheal responsiveness and the expression of Gata3 and Tbx21 genes. Forty male Wistar rats were allocated  randomly  into four experimental groups: healthy rats (control group), sensitized rats (OVA group), sensitized rats receiving Kit- cells (OVA+Kit- group) and sensitized rats receiving Kit+ cells (OVA+Kit+ group). Total and differential white blood cell counts, tracheal responsiveness to cumulative methacholine concentrations and histopathological analysis were evaluated. The results showed a statistically significant increase in total white blood cell, eosinophil and neutrophil counts, tracheal contractility, Gata3 expression and prototypical histopathology of asthma. Along with these conditions, we found that the number of lymphocytes was decreased and expression of Tbx21 diminished in sensitized rats compared with control animals. Monitoring of labelled tagged cells confirmed successful engraftment of transplanted cells in pulmonary tissue. Juxtaposition of Kit+ cells changed the blood leucogram closer to the control values. Kit+ cells increased the expression of Tbx21 and suppressed Gata3 (P < 0.05). In the OVA+Kit+ group, tracheal responsiveness was improved coincident with increased pulmonary regeneration. In conclusion, this study showed that intratracheal administration of bone marrow-derived Kit+ cells, but not Kit- cells, could be effective in the alleviation of asthma, presumably by the modulation of Gata3 and Tbx21.