SDF-1/CXCR4 axis enhances the immunomodulation of human endometrial regenerative cells in alleviating experimental colitis

Abstract

Endometrial regenerative cells (ERCs) are a new type of mesenchymal-like stromal cells, and their therapeutic potential has been tested in a variety of disease models. SDF-1/CXCR4 axis plays a chemotaxis role in stem/stromal cell migration. The aim of the present study was to investigate the role of SDF-1/CXCR4 axis in the immunomodulation of ERCs on the experimental colitis. The immunomodulation of ERCs in the presence or absence of pretreatment of SDF-1 or AMD3100 was examined in both in vitro cell culture system and dextran sulphate sodium-induced colitis in mice. The results showed that SDF-1 increased the expression of CXCR4 on the surface of ERCs. As compared with normal ERCs, the SDF-1-treated, CXCR4 high-expressing ERCs more significantly suppressed dendritic cell population as well as stimulated both type 2 macrophages and regulatory T cells in vitro and in vivo. Meanwhile, SDF-1-pretreated ERCs increased the generation of anti-inflammatory factors (e.g., IL-4, IL-10) and decreased the pro-inflammatory factors (e.g., IL-6, TNF-α). In addition, SDF-1-pretreated CM-Dil-labeled ERCs were found to engraft to injured colon. Our results may suggest that an SDF-1-induced high level of CXCR4 expression enhances the immunomodulation of ERCs in alleviating experimental colitis in mice.

Stromal Cell-Derived Factor-1 Enhances the Therapeutic Effects of Human Endometrial Regenerative Cells in a Mouse Sepsis Model

“…To investigate the effect of SDF-1 on the expression of CXCR4 on ERC surface, ERCs, which had been divided into 24-well plate (5 × 10 4 cells/well), were cocultured with two concentrations of SDF-1 (0 ng/ml, 50 ng/ml) for 72 hours at 37°C (n = 6/concentration). And as verified previously, SDF-1 at 50 ng/ml can maximize the CXCR4 expression stimulated by SDF-1 coculture on the surface of ERCs [9]. Then, ERCs were labeled with CXCR4 antibody (anti-CD184-PE, BioLegend, San Diego, USA), and the percentage of CXCR4 + ERCs was measured using flow cytometry.…”

“…Also, SDF-1/CXCR4 plays an important role in the migration of MSC to the injury sites [23]. More importantly, verified by previous literatures, CXCR4 is considered to express on the surface of ERCs and can be stimulated to a higher expression after ERCs cocultured with SDF-1 [9]. Given previous researches, SDF-1/CXCR4 signaling pathway is expected to play a vital role in affecting ERCs migration, secretion, and immune regulation.…”

“…SDF-1/CXCR4 pathway plays a vital role in mesenchymal stem cells migration, secretion [28], and immune regulation [29]. It has been also proven in several studies that human ERCs are able to migrate to the injured sites in mice and play a therapeutic role in immunoregulation [9,13]. However, the role of SDF-1/CXCR4 pathway in the therapeutic effects of ERCs needs to be elucidated in more disease models.…”

“…For AMD3100-pretreated ERCs, ERCs were cocultured with AMD3100 (an antagonist of CXCR4 receptor, 5 mg/kg) (Selleckchem, Shanghai, China) solution for 30 minutes before injection, as described by previous literature [9] and product specifications. For SDF-1-pretreated ERCs, ERCs were cocultured with SDF-1 solution (50 ng/ml) (PeproTech, Rocky Hill, USA) for 72 hours before injection, which can maximize the CXCR4 expression stimulated by SDF-1 coculture on the surface of ERCs, as verified previously [9]. In addition, the ERCs after coculture with SDF-1 and AMD3100 had been washed with PBS five times to eliminate the effects of residual SDF-1 and AMD3100 on the experiment.…”

“…They demonstrated that ERCs have the ability to self-regenerate and differentiate into specific cell lines in appropriate medium [8]. It is worth noting that ERCs have many advantages in clinical applications, including noninvasive acquisition methods, sufficient sources, high reproductive rate, multidirectional differentiation potential, immunomodulatory ability, and large-scale amplification without morphological variation [9]. Furthermore, ERCs do not express MHC class I molecules and only express low levels of MHC class II molecules [10], which enables ERCs with low immunogenicity to function smoothly in mice without rejection.…”