EphA2-positive human umbilical cord-derived mesenchymal stem cells exert anti-fibrosis and immunomodulatory activities via secretion of prostaglandin E2

Therapeutic strategies to target connective tissue growth factor in fibrotic lung diseases

The treatment of interstitial lung diseases, including idiopathic pulmonary fibrosis (IPF), remains challenging as current available antifibrotic agents are not effective in halting disease progression. Connective tissue growth factor (CTGF), also known as cellular communication factor 2 (CCN2), is a member of the CCN family of proteins that regulates cell signaling through cell surface receptors such as integrins, the activity of cytokines/growth factors, and the turnover of extracellular matrix (ECM) proteins. Accumulating evidence indicates that CTGF plays a crucial role in promoting lung fibrosis through multiple processes, including inducing transdifferentiation of fibroblasts to myofibroblasts, epithelial-mesenchymal transition (EMT), and cooperating with other fibrotic mediators such as TGF-β. Increased expression of CTGF has been observed in fibrotic lungs and inhibiting CTGF signaling has been shown to suppress lung fibrosis in several animal models. Thus, the CTGF signaling pathway is emerging as a potential therapeutic target in IPF and other pulmonary fibrotic conditions. This review provides a comprehensive overview of the current evidence on the pathogenic role of CTGF in pulmonary fibrosis and discusses the current therapeutic agents targeting CTGF using a systematic review approach.

Human Umbilical Cord Mesenchymal Stem Cells in Combination with Hyaluronic Acid Ameliorate the Progression of Knee Osteoarthritis

The aim of this study is to evaluate the feasibility and usefulness of the human umbilical cord mesenchymal stem cells (hUC-MSCs) and hyaluronan acid (HA) combination to attenuate osteoarthritis progression in the knee while simultaneously providing some insights on the mitigation mechanism. In vitro, the effect of hUC-MSCs with HA treatment on chondrocyte cell viability and the cytokine profile were analyzed. Additionally, the antioxidation capability of hUC-MSCs-CM (conditioned medium) with HA towards H2O2-induced chondrocyte cell damage was evaluated. The HA addition increased the hUC-MSC antioxidation capability and cytokine secretion, such as Dickkopf-related protein 1 (DKK-1) and hepatocyte growth factor (HGF), while no adverse effect on the cell viability was observed. In vivo, the intra-articular injection of hUC-MSCs with HA to a mono-iodoacetate (MIA)-induced knee osteoarthritis (KOA) rat model was performed and investigated. Attenuation of the KOA progression in the MIA-damaged rat model was seen best in hUC-MSCs with a HA combination compared to the vehicle control or each individual element. Combining hUC-MSCs and HA resulted in a synergistic effect, such as increasing the cell therapeutic capability while incurring no observable adverse effects. Therefore, this combinatorial therapy is feasible and has promising potential to ameliorate KOA progression.

Potential surrogate quantitative immunomodulatory potency assay for monitoring human umbilical cord-derived mesenchymal stem cells production

Mesenchymal stem cells (MSCs) play an important role as immune modulator through interaction with several immune cells, including macrophages. In this study, the immunomodulatory potency of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) was demonstrated in the in vivo middle cerebral artery occlusion (MCAo)-induced brain injury rat model and in vitro THP-1-derived macrophages model. At 24 h after induction of MCAo, hUC-MSCs was administered via tail vein as a single dose. Remarkably, hUC-MSCs could inhibit M1 polarization and promote M2 polarization of microglia in vivo after 14 days induction of MCAo. Compared with THP-1-derived macrophages which had been stimulated by lipopolysaccharide, the secretion of proinflammatory cytokines, tumor necrosis factor-α (TNF-α) and interferon-γ inducible protein (IP-10), were significantly reduced in the presence of hUC-MSCs. Moreover, the secretion of anti-inflammatory cytokine, interleukin-10 (IL-10), was significantly increased after cocultured with hUC-MSCs. Prostaglandins E2 (PGE2), secreted by hUC-MSCs, is one of the crucial immunomodulatory factors and could be inhibited in the presence of COX2 inhibitor, NS-398. PGE2 inhibition suppressed hUC-MSCs immunomodulatory capability, which was restored after addition of synthetic PGE2, establishing the minimum amount of PGE2 required for immunomodulation. In conclusion, our data suggested that PGE2 is a crucial potency marker involved in the therapeutic activity of hUC-MSCs through macrophages immune response modulation and cytokines regulation. This study provides the model for the development of a surrogate quantitative potency assay of immunomodulation in stem cells production.

Effects of Human Umbilical Cord-Derived Mesenchymal Stem Cells on the Acute Cigarette Smoke-Induced Pulmonary Inflammation Model

Cigarette smoke (CS) has been reported to induce oxidative stress and inflammatory process in the lungs. However, the role of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in the regulation of pulmonary inflammation remains unclear. The objective of this study is to investigate the effects of hUC-MSCs on lung inflammation in the acute CS-induced pulmonary inflammation animal model. Eight-week-old male C57BL/6 mice were intravenously administered 3 × 10⁶, 1 × 10⁷, and 3 × 10⁷ cells/kg of hUC-MSCs as well as normal saline alone (control) after 3 days of CS exposure. Mice exposed to high-efficiency particulate air (HEPA)-filtered room air served as the CS control group. High-dose (3 × 10⁷ cells/kg) hUC-MSC administration significantly decreased tumor necrosis factor (TNF)-α in the bronchoalveolar lavage fluid (BALF) of CS-exposed mice (p < 0.05). The chemokine (CXC motif) ligand 1/keratinocyte chemoattractant (CXCL1/KC) in BALF were significantly reduced by low-dose (3 × 10⁶ cells/kg) and high-dose (3 × 10⁷ cells/kg) hUC-MSC (p < 0.05). Medium-dose hUC-MSC administration decreased interleukin (IL)-1β in lung of mice, and TNF-α and caspase-3 were decreased in the lung of CS-exposed mice by medium- and high-dose MSC (p < 0.05). Low-dose hUC-MSCs significantly elevated serum CXCL1/KC and IL-1β in CS-exposed mice (p < 0.05). Our results suggest that high-dose hUC-MSCs reduced pulmonary inflammation and had antiapoptotic effects in acute pulmonary inflammation.

hUMSCs regulate the differentiation of ovarian stromal cells via TGF-β1/Smad3 signaling pathway to inhibit ovarian fibrosis to repair ovarian function in POI rats

Objective

The basic pathological changes of primary ovarian insufficiency (POI) include ovarian tissue fibrosis and follicular development disorders. The human umbilical cord mesenchymal stem cell (hUMSC) transplantation has been shown an effective method to improve the ovarian function in POI rat model; however, the exact mechanisms are still unclear. The purpose of this study is to investigate whether the recovery of ovarian function in POI rats is related to the inhibition of tissue fibrosis following hUMSC transplantation. Furthermore, the transforming growth factor-β₁ (TGF-β₁) signaling pathway is explored to determine the mechanisms of ovarian function recovery through its inhibition of tissue fibrosis.

Methods

The primary ovarian insufficiency (POI) rat model was established by intraperitoneal injection of chemotherapy drug cisplatin (CDDP) for 7 days. The levels of serum sex hormones were measured using enzyme-linked immunosorbent assay (ELISA). The tissue fibrosis in the ovary was examined using Masson staining and Sirius red staining. The collagen fibers in the ovarian tissues were detected by Western blot analysis. To investigate the mechanisms of ovarian function recovery following hUMSC transplantation, ovarian stromal cells were isolated from the ovarian cortex of immature rats. The expression of Cytochrome P450 17A1 (Cyp17a1) and fibrosis marker of alpha smooth muscle actin (α-SMA) in ovarian stromal cells was examined using immunofluorescence analysis. Also, the protein levels of Cyp17a1 and α-SMA in ovarian stromal cells were examined by Western blot analysis. The expression of TGF-β₁ and Smad3 signals was measured by Western blot and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis.

Results

The results show that the function of the ovary in POI rats was significantly improved after hUMSC transplantation. The expression of fibrosis markers (α-SMA) and production of Collagen Type I (Collagen I) and Collagen Type III (Collagen III) in POI rats were significantly inhibited in POI rats following hUMSC transplantation. In the cultured ovarian stromal cells, the decrease of TGF-β₁ and p-Smad3 protein expression was observed in hUMSC-treated POI rats. The treatment with TGF-β₁ inhibitor of SB431542 further confirmed this signal pathway was involved in the process.

Conclusion

Our study demonstrated that the TGF-β₁/Smad3 signaling pathway was involved in the inhibition of ovarian tissue fibrosis, which contributed to the restoration of ovarian function in POI rats following hUMSC transplantation.

Comparative Proteomic Analysis Identifies EphA2 as a Specific Cell Surface Marker for Wharton's Jelly-Derived Mesenchymal Stem Cells

Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) are a valuable tool in stem cell research due to their high proliferation rate, multi-lineage differentiation potential, and immunotolerance properties. However, fibroblast impurity during WJ-MSCs isolation is unavoidable because of morphological similarities and shared surface markers. Here, a proteomic approach was employed to identify specific proteins differentially expressed by WJ-MSCs in comparison to those by neonatal foreskin and adult skin fibroblasts (NFFs and ASFs, respectively). Mass spectrometry analysis identified 454 proteins with a transmembrane domain. These proteins were then compared across the different cell-lines and categorized based on their cellular localizations, biological processes, and molecular functions. The expression patterns of a selected set of proteins were further confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting, and immunofluorescence assays. As anticipated, most of the studied proteins had common expression patterns. However, EphA2, SLC25A4, and SOD2 were predominantly expressed by WJ-MSCs, while CDH2 and Talin2 were specific to NFFs and ASFs, respectively. Here, EphA2 was established as a potential surface-specific marker to distinguish WJ-MSCs from fibroblasts and for prospective use to prepare pure primary cultures of WJ-MSCs. Additionally, CDH2 could be used for a negative-selection isolation/depletion method to remove neonatal fibroblasts contaminating preparations of WJ-MSCs.

Stem cell therapy for preventing neonatal diseases in the 21st century: Current understanding and challenges

Diseases of the preterm newborn such as bronchopulmonary dysplasia, necrotizing enterocolitis, cerebral palsy, and hypoxic-ischemic encephalopathy continue to be major causes of infant mortality and long-term morbidity. Effective therapies for the prevention or treatment for these conditions are still lacking as recent clinical trials have shown modest or no benefit. Stem cell therapy is rapidly emerging as a novel therapeutic tool for several neonatal diseases with encouraging pre-clinical results that hold promise for clinical translation. However, there are a number of unanswered questions and facets to the development of stem cell therapy as a clinical intervention. There is much work to be done to fully elucidate the mechanisms by which stem cell therapy is effective (e.g., anti-inflammatory versus pro-angiogenic), identifying important paracrine mediators, and determining the timing and type of therapy (e.g., cellular versus secretomes), as well as patient characteristics that are ideal. Importantly, the interaction between stem cell therapy and current, standard-of-care interventions is nearly completely unknown. In this review, we will focus predominantly on the use of mesenchymal stromal cells for neonatal diseases, highlighting the promises and challenges in clinical translation towards preventing neonatal diseases in the 21st century.

The effects of human umbilical cord-derived mesenchymal stem cell transplantation on endometrial receptivity are associated with Th1/Th2 balance change and uNK cell expression of uterine in autoimmune premature ovarian failure mice

Background

To explore the mechanism of human umbilical cord-derived mesenchymal stem cell (hUMSC) transplantation to improve ovarian function and the endometrial receptivity in autoimmune premature ovarian failure (POF) mice.

Methods

The POF model was established in mice treated with zona pellucida 3 polypeptide fragment (zona pellucida 3, ZP3). The hUMSCs were transplanted into the POF mice through tail vein injection. Following the transplantation, the serum hormone levels of follicle stimulating hormone (FSH), estrogen (E₂), progesterone (P), γ-interferon (IFN-γ), interleukin-2 (IL-2), and interleukin-4 (IL-4) were evaluated by ELISA analysis. Morphological changes of ovarian and uterus tissues were examined by HE staining and immunohistochemistry. The expression of Th1/Th2 cytokines of T cells in spleen and CD56⁺CD16⁻ cells (uterine natural killer cells, uNK cells) in uterine was measured by flow cytometry (FCM) and immunohistochemistry. The expression of HOXA10 in uterine endometrium was examined by immunohistochemistry and RT-PCR analysis. The pinopodes of epithelial cells in uterine endometrium were examined by scanning electron microscopy.

Results

Following hUMSC transplantation, the serum levels of E₂, P, and IL-4 were increased but FSH, IFN-γ, and IL-2 levels were decreased in POF mice. Also, the transplantation of hUMSCs caused an increase in total number of healthy follicles and decrease of atresia follicles. The expression of HOXA10 gene was significantly increased but the CD56⁺CD16⁻ uNK cells decreased in the endometrium of uterine. The ratio of Th1/Th2 cytokines was also significantly decreased.

Conclusion

The data suggest that the recovery of ovarian function and endometrial receptivity in POF mice was regulated by the balance of Th1/Th2 cytokines and expression of uNK cells in the endometrium following hUMSC transplantation.