Prevention of LPS-induced acute respiratory distress syndrome in sheep by bone marrow-derived mesenchymal stem/stromal cells

Regenerative medicine in lung diseases: A systematic review

Regenerative medicine has opened the door to the exploration of new therapeutic methods for the treatment of various diseases, especially those associated with local or general disregulation of the immune system. In pulmonary diseases, new therapeutic strategies have emerged that are aimed at restoring functional lung tissue rather than alleviating symptoms. These strategies focus on tissue regeneration using stem cells and/or their derivatives or replacement of dysfunctional tissue using biomedical engineering. Animal health can directly benefit from regenerative therapy strategies and also serve as a translational experimental model for human disease. Several clinical trials have been conducted to evaluate the effects of cellular treatment on inflammatory lung disease in animals. Data reported to date show several beneficial effects in ex vivo and in vivo models; however, our understanding of the mechanisms that regenerative therapies exert on diseased tissues remains incomplete.

Effects of different concentrations of mesenchymal stem cells treatment on LPS-induced acute respiratory distress syndrome rat model

PURPOSE

This study was prospectively designed to investigate the effects of different concentrations of mesenchymal stem cells treatment on respiratory mechanics, oxygenation, hemodynamics and inflammatory response in LPS-induced acute respiratory distress syndrome (ARDS) rat model. Methods: One hundred and twenty six LPS-induced ARDS model rats (weighted 200-220 g) were randomly divided into three groups: 1) Control group (N = 42); 2) low-dose hUC-MSC treatment group (MSC group 1, 1x107 cell/kg, N = 42); 3) high-dose hUC-MSC treatment group (MSC group 2, 2x107 cell/kg, N = 42), sham operation group as healthy group (N = 15). The rats were observed closely for 24 hours after hUC-MSC treatment, and the survival rate was calculated. At 24 hours, all rats were tested for hemodynamics, blood gas analysis, heart, lung, liver and kidney functions, inflammatory factors detection in blood samples and broncho-alveolar lavage fluid (BALF). The lung tissue of the rats was collected for HE staining analysis. Results: After LPS injection, ARDS was obvious in all LPS-infused rat groups, consistent with severe acute lung injury and high death rate. However, compared with the control group, a single intravenous injection hUC-MSC at dose of 1 × 107 cells/kg (low dose group) and 2 × 107 cells/kg (high dose group) reduced the mortality of rats with LPS-induced ARDS, as well as improving the lung function, increased the arterial oxygen pressure, improved the heart function, and reduced the levels of inflammatory factors including IL-1β, IL-6, and TNF-α. In addition, the high dose MSC group showed better lung injury therapeutic effects than the low dose MSC group. Data from this study demonstrated that injection of hUC-MSC had a significant therapeutic effect in treating the rat model of LPS-induced ARDS and multiple organ function injury.

Small Ruminants and Its Use in Regenerative Medicine: Recent Works and Future Perspectives

Simple Summary

Small ruminants such as sheep and goats have been increasingly used as animal models due to their dimensions, physiology and anatomy identical to those of humans. Their low costs, ease of accommodation, great longevity and easy handling make them advantageous animals to be used in a wide range of research work. Although there is already a lot of scientific literature describing these species, their use still lacks some standardization. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models for scientific research.

Abstract

Medical and translational scientific research requires the use of animal models as an initial approach to the study of new therapies and treatments, but when the objective is an exploration of translational potentialities, classical models fail to adequately mimic problems in humans. Among the larger animal models that have been explored more intensely in recent decades, small ruminants, namely sheep and goats, have emerged as excellent options. The main advantages associated to the use of these animals in research works are related to their anatomy and dimensions, larger than conventional laboratory animals, but very similar to those of humans in most physiological systems, in addition to their low maintenance and feeding costs, tendency to be docile, long life expectancies and few ethical complications raised in society. The most obvious disadvantages are the significant differences in some systems such as the gastrointestinal, and the reduced amount of data that limits the comparison between works and the validation of the characterization essays. Despite everything, recently these species have been increasingly used as animal models for diseases in different systems, and the results obtained open doors for their more frequent and advantageous use in the future. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models, with a focus on regenerative medicine, to group the most relevant works and results published recently and to highlight the potentials for the near future in medical research.