Immunologic regulatory effects of human umbilical cord blood‐derived mesenchymal stem cells in a murine ovalbumin asthma model

Summary Background Mesenchymal stem cells ( MSC s) have multiple immunomodulatory properties and hold therapeutic potential for inflammatory diseases. However, the therapeutic and immunologic effects of human umbilical cord blood‐derived MSC s (hu MSC s) remain largely unexamined for asthma. Objective This study was to investigate the immunomodulatory properties of hu MSC s in an ovalbumin ( OVA )‐induced murine asthma model. Methods Mice were injected intraperitoneally with OVA and an aluminium hydroxide adjuvant. hu MSC s were administered via the tail vein (5×10 5 cells/100 uL) to female BALB /c mice prior to the initial OVA challenge. The effects of hu MSC s were assessed by investigating airway hyperresponsiveness, histological changes, inflammatory cell numbers, serum allergen‐specific antibodies, cytokine production in spleen, lung tissue, and bronchoalveolar lavage ( BAL ) fluid as well as expansion of regulatory T cells. Results Administration of hu MSC s significantly reduced methacholine bronchial hyperresponsiveness and eosinophil counts in BAL cells. Similarly, there was a significant decrease in serum OVA ‐specific IgE and IgG1 levels along with Th2 cytokine production ( IL ‐4, IL ‐5, and IL ‐13) in the lung and spleen tissues, whereas increased percentage of regulatory T cells was observed after treatment with hu MSC s. Conclusions Our results suggest that hu MSC treatment reduces OVA ‐induced allergic inflammation, which could be mediated by regulatory T cells.