RETRACTED ARTICLE: Overexpressing p130/E2F4 in mesenchymal stem cells facilitates the repair of injured alveolar epithelial cells in LPS-induced ARDS mice

Abstract

Background Low differentiation rates of mesenchymal stem cells (MSCs) limit their therapeutic effects on patients in clinical studies. Our previous study demonstrated that overexpressing p130 or E2F4 affected the multipotential differentiation of MSCs, and the underlying mechanism was attributed to the regulation of the G1 phase. Improving the efficiency of MSC differentiation into epithelial cells is considered to be a new method. Therefore, this study was conducted to evaluate the effects of overexpressing p130 or E2F4 in MSCs on improving re-epithelization in lipopolysaccharide (LPS)-induced ARDS animals. Methods Mouse MSCs (mMSCs) stably transfected with p130 and E2F4 were transplanted intratracheally into LPS-induced ARDS mice. After 7 and 14 days, the mice were sacrificed, and the histopathology of the lungs was assessed by haematoxylin-eosin staining and lung injury scoring. Homing and differentiation of mMSCs were analysed by labelling and tracking mMSCs with NIR815 dye and immunofluorescent staining. Surfactant proteins A and C and occludin in the lungs were assessed by western blot. Permeability was evaluated by analysing the protein concentration of BALF using ELISA. Alveolar fluid clearance was assessed by absorbance measurements of BALF. Lung fibrosis was assessed by Masson’s trichrome staining and Ashcroft scoring. Results The engraftment of mMSCs overexpressing p130 or E2F4 led to attenuated histopathological impairment of the lung tissue, and the lung injury scores of the LPS+mBM-MSC-p130 and LPS+mBM-MSC-E2F4 groups were also decreased ( p < 0.05). Overexpression of p130 or E2F4 also increased the retention of mMSCs in the lung ( p < 0.05), increased differentiation into type II alveolar epithelial cells ( p < 0.05), and improved alveolar epithelial permeability ( p < 0.05). Additionally, mMSCs overexpressing p130 or E2F4 inhibited lung fibrosis according to the deposition of collagen and the fibrosis score in the lungs ( p < 0.05). Conclusion Overexpressing p130 or E2F4 in mMSCs could further improve the injured structure and function of epithelial cells in the lungs of ARDS mice as a result of improved differentiation of mMSCs into epithelial cells. Electronic supplementary material The online version of this article (10.1186/s13287-019-1169-1) contains supplementary material, which is available to authorized users.

Overexpression of TGFβ1 in murine mesenchymal stem cells improves lung inflammation by impacting the Th17/Treg balance in LPS-induced ARDS mice

“…According to Masson's staining or speci c mRNA expression, MSCs overexpressing TGFβ1 did not signi cantly increase pulmonary brosis in ARDS mice. In addition, our previous study also found that mMSCs could further improve the epithelial injury and pulmonary brosis of ARDS mice by increasing differentiation into type II epithelial cells through p130/E2F4 pathway 15 , indicating that there might be no side effects related to MSCs transplantation.…”

“…The mBM-MSC (1×10 6 /well seeded in six-well cell culture plates) were transduced with viral supernatant at a multiplicity of infection (MOI) of 160:1 for 24 hours. Then, the stable cell lines were harvested after selection using blasticidin (BSD; InvivoGen) at the minimal lethal concentration (6 μg/mL) as previously described 15 and cultured in normal culture medium for 20 passages after transduction. Finally, the transduction efficiency of mBM-MSC and the percentage of eGFP-positive cells were evaluated by fluorescence microscopy and flow cytometry (FCM) analysis using a FACSCalibur flow cytometer (Becton-Dickinson, Franklin Lakes, NJ, USA).…”

“…Bronchoalveolar lavage fluid (BALF) was collected by flushing 1 mL of ice-cold PBS back and forth three times through a tracheal cannula as previously described 14,15 . After centrifugation at 800 ×g for 10 minutes, total protein (TP), albumin (ALB), tumour necrosis factor-α (TNF-α), IL-1β and IL-6 concentrations in the BALF were measured by ELISA kits (Cusabio Biotech, Wuhan, China; Excell Bio, Shanghai, China).…”

“…Then, NIR815-labelled cells (5×10 5 cells) were directly administered into the trachea of the mice in different groups according to the protocol . After 1 d, 3 d and 7 d post-transplantation, three mice at each time point were sacrificed, and ex vivo lungs were imaged using a Maestro in vivo optical imaging system (excitation = 786 nm, emission =814 nm, and 4,000 ms exposure time; Caliper Life Sciences, MA, Boston, USA) 15,17 . The autofluorescence spectra were then unmixed based on their spectral patterns using Maestro 2.4 software (Caliper Life Sciences).…”

Leptin promotes methionine adenosyltransferase 2A expression in hepatic stellate cells by the downregulation of E2F‐4 via the β‐catenin pathway

“…These results pointed to an association of the β‐catenin pathway with E2F‐4. Notably, E2F‐4 was also demonstrated to be involved in inhibiting lung fibrosis …”