Efficacy and safety of mesenchymal stromal cells in preclinical models of acute lung injury: a systematic review protocol

NMDAR activation attenuates the protective effect of BM-MSCs on bleomycin-induced ALI via the COX-2/PGE2 pathway

N-methyl-d-aspartate (NMDA) receptor (NMDAR) activation mediates glutamate (Glu) toxicity and involves bleomycin (BLM)-induced acute lung injury (ALI). We have reported that bone marrow-derived mesenchymal stem cells (BM-MSCs) are NMDAR-regulated target cells, and NMDAR activation inhibits the protective effect of BM-MSCs on BLM-induced pulmonary fibrosis, but its effect on ALI remains unknown. Here, we found that Glu release was significantly elevated in plasma of mice at d 7 after intratracheally injected with BLM. BM-MSCs were pretreated with NMDA (the selective agonist of NMDAR) and transplanted into the recipient mice after the BLM challenge. BM-MSCs administration significantly alleviated the pathological changes, inflammatory response, myeloperoxidase activity, and malondialdehyde content in the damaged lungs, but NMDA-pretreated BM-MSCs did not ameliorate BLM-induced lung injury in vivo. Moreover, NMDA down-regulated prostaglandin E2 (PGE2) secretion and cyclooxygenase (COX)-2 expression instead of COX-1 expression in BM-MSCs in vitro. We also found that NMDAR1 expression was increased and COX-2 expression was decreased, but COX-1 expression was not changed in primary BM-MSCs of BLM-induced ALI mice. Further, the cultured supernatants of lipopolysaccharide (LPS)-pretreated RAW264.7 macrophages were collected to detect inflammatory factors after co-culture with NMDA-pretreated BM-MSCs. The co-culture experiments showed that NMDA precondition inhibited the anti-inflammatory effect of BM-MSCs on LPS-induced macrophage inflammation, and PGE2 could partially alleviate this inhibition. Our findings suggest that NMDAR activation attenuated the protective effect of BM-MSCs on BLM-induced ALI in vivo. NMDAR activation inhibited COX-2 expression and PGE2 secretion in BM-MSCs and weakened the anti-inflammatory effect of BM-MSCs on LPS-induced macrophage inflammation in vitro. In conclusion, NMDAR activation attenuates the protective effect of BM-MSCs on BLM-induced ALI via the COX-2/PGE2 pathway. Keywords: Acute Lung Injury, BM-MSCs, NMDA receptor, COX-1/2, PGE2.

Sex-based analysis of treatment responses in animal models of sepsis: a preclinical systematic review protocol

BACKGROUND

The importance of investigating sex- and gender-dependent differences has been recently emphasized by major funding agencies. Notably, the influence of biological sex on clinical outcomes in sepsis is unclear, and observational studies suffer from the effect of confounding factors. The controlled experimental environment afforded by preclinical studies allows for clarification and mechanistic evaluation of sex-dependent differences. We propose a systematic review to assess the impact of biological sex on baseline responses to disease induction as well as treatment responses in animal models of sepsis. Given the lack of guidance surrounding sex-based analyses in preclinical systematic reviews, careful consideration of various factors is needed to understand how best to conduct analyses and communicate findings.

METHODS

MEDLINE and Embase will be searched (2011-present) to identify preclinical studies of sepsis in which any intervention was administered and sex-stratified data reported. The primary outcome will be mortality. Secondary outcomes will include organ dysfunction, bacterial load, and IL-6 levels. Study selection will be conducted independently and in duplicate by two reviewers. Data extraction will be conducted by one reviewer and audited by a second independent reviewer. Data extracted from included studies will be pooled, and meta-analysis will be conducted using random effects modeling. Primary analyses will be stratified by animal age and will assess the impact of sex at the following time points: pre-intervention, in response to treatment, and post-intervention. Risk of bias will be assessed using the SYRCLE's risk-of-bias tool. Illustrative examples of potential methods to analyze sex-based differences are provided in this protocol.

DISCUSSION

Our systematic review will summarize the current state of knowledge on sex-dependent differences in sepsis. This will identify current knowledge gaps that future studies can address. Finally, this review will provide a framework for sex-based analysis in future preclinical systematic reviews.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022367726.

Emodin Protects Against Lipopolysaccharide-Induced Acute Lung Injury via the JNK/Nur77/c-Jun Signaling Pathway

Background: Acute lung injury (ALI) is a serious inflammatory disease with clinical manifestations of hypoxemia and respiratory failure. Presently, there is no effective treatment of ALI. Although emodin from Rheum palmatum L. exerts anti-ALI properties, the underlying mechanisms have not been fully explored.

Purpose: This study aimed to investigate the therapeutic effect and mechanism of emodin on LPS-induced ALI in mice.

Methods: RAW264.7 cells and zebrafish larvae were stimulated by LPS to establish inflammatory models. The anti-inflammatory effect of emodin was assessed by ELISA, flow cytometric analysis, and survival analysis. In vitro mechanisms were explored by using Western blotting, luciferase assay, electrophoretic mobility shift assay (EMSA), and small interfering RNA (siRNA) approach. The acute lung injury model in mice was established by the intratracheal administration of LPS, and the underlying mechanisms were assessed by detecting changes in histopathological and inflammatory markers and Western blotting in lung tissues.

Results: Emodin inhibited the inflammatory factor production and oxidative stress in RAW264.7 cells, and prolonged the survival of zebrafish larvae after LPS stimulation. Emodin suppressed the expression levels of phosphorylated JNK at Thr183/tyr182 and phosphorylated Nur77 at Ser351 and c-Jun, and increased the expression level of Nur77 in LPS-stimulated RAW264.7 cells, while these regulatory effects of emodin on Nur77/c-Jun were counteracted by JNK activators. The overexpression of JNK dampened the emodin-mediated increase in Nur77 luciferase activity and Nur77 expression. Moreover, the inhibitory effect of emodin on c-Jun can be attenuated by Nur77 siRNA. Furthermore, emodin alleviated LPS-induced ALI in mice through the regulation of the JNK/Nur77/c-Jun pathway.

Conclusions: Emodin protects against LPS-induced ALI through regulation on JNK/Nur77/c-Jun signaling. Our results indicate the potential of emodin in the treatment of ALI.

Definition and Characteristics of Mesenchymal Stromal Cells in Preclinical and Clinical Studies: A Scoping Review

Mesenchymal stromal cells (MSCs) are widely used in preclinical and clinical research. Despite minimal criteria to define MSCs provided by the International Society for Cell and Gene Therapy (ISCT), concerns have been raised about inconsistent descriptions of cell products used. To address the question "How are MSCs currently defined and characterized?" we conducted a scoping review on original MSC preclinical and clinical studies published over a 3-month period. Selected studies identified from a systematic search of MEDLINE and Embase were categorized as follows: Clinical, Animal, Biology, or Biomaterial studies. Data were extracted from a randomly selected subsample of studies. We extracted information, including epidemiological characteristics of studies, study design, ISCT criteria, and MSC characterization and culture condition. A total of 1053 articles were included and among them, 318 articles were analyzed. Overall, 18% of the articles explicitly referred to the ISCT minimal criteria for MSC. MSC characteristics and culture conditions were inconstantly reported (eg, viability assay reported in only 18% of the articles). Only 20% of documents reported at least 1 functional assay. Clinical studies showed inconsistent completeness in reporting relevant information on the MSC characterization and cell manufacturing processes. These results suggest that further development and implementation of a consensus definition of MSCs and reporting guidelines are needed to enhance rigor, reproducibility, and transparency in MSC research.

Physalin B ameliorates inflammatory responses in lipopolysaccharide-induced acute lung injury mice by inhibiting NF-κB and NLRP3 via the activation of the PI3K/Akt pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Physalin B (PB) is an active constituent of Physalis alkekengi L. var. Franchetii, which is a traditional medicine for clearing heat and detoxification, resolving phlegm, and diuresis. It has been commonly applied to treat sore throat, phlegm-heat, cough, dysuria, pemphigus, and eczema.

AIM OF STUDY

Physalin B has shown efficacy as an anti-acute lung injury (ALI) agent previously; however, its mechanisms of action remain unclear. In the present study, we established a lipopolysaccharide-induced septic ALI model using BALB/c mice to further confirm the therapeutic potential of PB and to assess the underlying molecular mechanisms.

MATERIALS AND METHODS

We used 75% ethanol and macroporous resin for extraction, separation, and enrichment of PB. The LPS-induced ALI mouse model was used to determine anti-inflammatory effects of PB. The severity of acute lung injury was evaluated by hematoxylin and eosin staining, wet/dry lung ratio, and myeloperoxidase (MPO) activity in lung tissue. An automatic analyzer was used to measure the arterial blood gas index. Protein levels of pro-inflammatory cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung tissue was measured using an ELISA. Quantitative RT-PCR was used to measure changes in RNA levels of pro-inflammatory cytokines in the lungs. A fluorometric assay kit was used for determination of apoptosis-related factors to assess anti-apoptotic effects of PB. Western blotting was used to assess levels of key pathway proteins and apoptosis-related proteins. Connections between the pathways were tested through inhibitor experiments.

RESULTS

Pretreatment with PB (15 mg kg^-1 d^-1, i.g.) significantly reduced lung wet/dry weight ratios and MPO activity in blood and BALF of ALI mice, and it alleviated LPS-induced inflammatory cell infiltration in lung tissue. The levels of pro-inflammatory factors TNF-α, IL-6, and IL-1β and their mRNA levels in blood, BALF, and lung tissue were reduced following PB pretreatment. PB pretreatment also downregulated the apoptotic factors caspase-3, caspase-9, and apoptotic protein Bax, and it upregulated apoptotic protein Bcl-2. The NF-κB and NLRP3 pathways were inhibited through activation of the PI3K/Akt pathway due to PB pretreatment, whereas administration of PI3K inhibitors increased activation of these pathways.

CONCLUSIONS

Taken together, our results suggest that the anti-ALI properties of PB are closely associated with the inactivation of NF-κB and NLRP3 by altering the PI3K/Akt pathway. Furthermore, our findings provide a novel strategy for application of PB as a potential agent for treating patients with ALI. To the best of our knowledge, this is the first study to elucidate the underlying mechanism of action of PB against ALI.

Direct comparison of different therapeutic cell types susceptibility to inflammatory cytokines associated with COVID-19 acute lung injury

Background

Although 90% of infections with the novel coronavirus 2 (COVID-19) are mild, many patients progress to acute respiratory distress syndrome (ARDS) which carries a high risk of mortality. Given that this dysregulated immune response plays a key role in the pathology of COVID-19, several clinical trials are underway to evaluate the effect of immunomodulatory cell therapy on disease progression. However, little is known about the effect of ARDS associated pro-inflammatory mediators on transplanted stem cell function and survival, and any deleterious effects could undermine therapeutic efficacy. As such, we assessed the impact of inflammatory cytokines on the viability, and paracrine profile (extracellular vesicles) of bone marrow-derived mesenchymal stromal cells, heart-derived cells, and umbilical cord-derived mesenchymal stromal cells.

Methods

All cell products were manufactured and characterized to established clinical release standards by an accredited clinical cell manufacturing facility. Cytokines and Extracellular vesicles in the cell conditioned media were profiled using proteomic array and nanoparticle tracking analysis. Using a survey of the clinical literature, 6 cytotoxic cytokines implicated in the progression of COVID-19 ARDS. Flow cytometry was employed to determine receptor expression of these 6 cytokines in three cell products. Based on clinical survey and flow cytometry data, a cytokine cocktail that mimics cytokine storm seen in COVID-19 ARDS patients was designed and the impact on cytokine cocktail on viability and paracrine secretory ability of cell products were assessed using cell viability and nanoparticle tracking analysis.

Results

Flow cytometry revealed the presence of receptors for all cytokines but IL-6, which was subsequently excluded from further experimentation. Despite this widespread expression, exposure of each cell type to individual cytokines at doses tenfold greater than observed clinically or in combination at doses associated with severe ARDS did not alter cell viability or extracellular vesicle character/production in any of the 3 cell products.

Conclusions

The paracrine production and viability of the three leading cell products under clinical evaluation for the treatment of severe COVID-19 ARDS are not altered by inflammatory mediators implicated in disease progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02699-7.

Salidroside Protects Against Influenza A Virus-Induced Acute Lung Injury in Mice

Influenza A virus infections can cause acute lung injury (ALI) in humans; thus, the identification of potent antiviral agents is urgently required. Herein, the effects of salidroside on influenza A virus-induced ALI were investigated in a murine model. BALB/c mice were intranasally inoculated with H1N1 virus and treated with salidroside. The results of this study show that salidroside treatment (30 and 60 mg/kg) significantly attenuated the H1N1 virus-induced histological alterations in the lung and inhibited inflammatory cytokine production. Salidroside also decreased the wet/dry ratio, viral titers, and Toll-like receptor 4 expression in the lungs. Therefore, salidroside may represent a potential therapeutic reagent for the treatment of influenza A virus-induced ALI.

Immunophenotypic characterization and therapeutics effects of human bone marrow- and umbilical cord-derived mesenchymal stromal cells in an experimental model of sepsis

Sepsis is a complicated multi-system disorder characterized by a dysregulated host response to infection. Despite substantial progress in the understanding of mechanisms of sepsis, translation of these advances into clinically effective therapies remains challenging. Mesenchymal Stromal Cells (MSCs) possess immunomodulatory properties that have shown therapeutic promise in preclinical models of sepsis. The therapeutic effects of MSCs may vary depending on the source and type of these cells. In this comparative study, the gene expression pattern and surface markers of bone marrow-derived MSCs (BM-MSCs) and umbilical cord-derived MSCs (UC-MSCs) as well as their therapeutic effects in a clinically relevant mouse model of polymicrobial sepsis, cecal ligation and puncture (CLP), were investigated. The results showed remarkable differences in gene expression profile, surface markers and therapeutic potency in terms of enhancing survival and pro/anti-inflammatory responses between the two MSC types. BM-MSCs improved survival concomitant with an enhanced systemic bacterial clearance and improved inflammatory profile post CLP surgery. Despite some improvement in the inflammatory profile of the septic animals, treatment with UC-MSCs did not enhance survival or bacterial clearance. Overall, the beneficial therapeutic effects of BM-MSCs over UC-MSCs may likely be attributed to their pro-inflammatory function, and to some extent anti-inflammatory features, reflected in their gene expression pattern enhancing macrophage polarization to M1/M2 phenotypes resulting in a balanced pro- and anti-inflammatory response against polymicrobial sepsis.

A streamlined proliferation assay using mixed lymphocytes for evaluation of human mesenchymal stem cell immunomodulation activity

BACKGROUND

Mesenchymal stromal cells (MSCs) have been proposed for treatment of acute respiratory distress syndrome (ARDS), graft versus host disease (GVHD), wound healing and trauma. A consensus is building that immunomodulation by MSCs is important for therapeutic potential. MSCs suppress peripheral blood mononuclear cell (PBMC) proliferation in vitro, potentially reflecting an ability to suppress PBMC inflammatory responses in vivo. Current mixed lymphocyte reaction (MLR) assays commonly used to evaluate MSC potency generally rely on either direct co-culture or indirect culture using transwell systems for monitoring the proliferation of isolated PBMCs in the presence of mitotically inactive MSCs. Proliferation of PBMCs is monitored by several methods, including incorporation of radiolabeled nucleotides, BRDU labeling and ELISA assay or flow cytometry of carboxyfluorescein labeled PBMCs. Here we present a streamlined assay using MSCs in a direct co-culture system with unmodified MSCs using a luminescent ATP assay to evaluate both PBMC and MSC proliferation/survival.

METHODS

PBMCs were isolated from fresh anti-coagulated whole blood by centrifugation over Ficoll-Paque in LeucoSep tubes. Isolated PBMCs from 8 to 10 donors were pooled and cryopreserved at 1 × 10⁷/ml in 50% RPMI medium,10% DMSO, 40% human AB serum. MSCs derived from bone marrow, adipose tissue or umbilical cord (BM-MSC, Ad-MSC, UC-MSC, respectively) were serially diluted starting at 50-60,000 cells/well and cultured in 96 well plates for 4-48 h in their respective medium. On Day 0, MSCs were washed, resuspended in PBMC media (RPMI with 10% FBS, 2 mM Glutamine, 10 mM HEPES, pH 7.4) and incubated with or without 150,000 freshly thawed pooled PBMCs/well, in the presence or absence of phytohemagglutinin A (PHA, 0-5 μg/ml). Proliferation of both MSCs (adherent) and PBMCs (non-adherent) was assessed by quantitation of ATP levels using the bioluminescent reagent Cell Titer-Glo (Promega). Culture supernatant contained PBMC, while washed adherent cells were primarily MSCs. Both cell types were incubated for 30 min with an equal volume of Cell Titer-Glo reagent and then assayed in white plates on a luminescence plate reader.

RESULTS

PBMC proliferation in response to PHA stimulation resulted in a robust increase in ATP by 72 h, with >6 fold increase over unstimulated PBMCs, which showed no increase. MSC proliferation was decreased <20% at the highest PHA concentrations. Co-culture with MSCs suppressed PBMC proliferation dependent upon MSC passage number, source, and prior growth conditions. Total time to complete the ATP assay was under an hour including incubations. With minimal manipulations in the assay, intra- and inter- assay variations averaged 11.1 and 15.7% respectively.

CONCLUSIONS

Direct co-culture of live unmodified MSCs with freshly thawed pooled PBMCs gives a robust determination of immunosuppression by MSCs with unparalleled ease. Graded responses can be determined, allowing comparison of potency between MSC preparations as in comparisons between freshly thawed and cultured MSCs as well as interferon-γ licensed MSCs. With the 96 well plate assay, far fewer PBMCs are generally required than in a typical flow cytometry determination. This streamlined assay can be performed within 72 h, without irradiating cells and without specialized equipment.

Forsythoside A inhibits adhesion and migration of monocytes to type II alveolar epithelial cells in lipopolysaccharide-induced acute lung injury through upregulating miR-124

Acute lung injury (ALI) is a severe disease for which effective drugs are still lacking at present. Forsythia suspensa is a traditional Chinese medicine commonly used to relieve respiratory symptoms in China, but its functional mechanisms remain unclear. Therefore, forsythoside A (FA), the active constituent of F. suspensa, was studied in the present study. Inflammation models of type II alveolar epithelial MLE-12 cells and BALB/c mice stimulated by lipopolysaccharide (LPS) were established to explore the effects of FA on ALI and the underlying mechanisms. We found that FA inhibited the production of monocyte chemoattractant protein-1 (MCP-1/CCL2) in LPS-stimulated MLE-12 cells in a dose-dependent manner. Moreover, FA decreased the adhesion and migration of monocytes to MLE-12 cells. Furthermore, miR-124 expression was upregulated after FA treatment. The luciferase report assay showed that miR-124 mimic reduced the activity of CCL2 in MLE-12 cells. However, the inhibitory effects of FA on CCL2 expression and monocyte adhesion and migration to MLE-12 cells were counteracted by treatment with a miR-124 inhibitor. Critically, FA ameliorated LPS-induced pathological damage, decreased the serum levels of tumor necrosis factor-α and interleukin-6, and inhibited CCL2 secretion and macrophage infiltration in lungs in ALI mice. Meanwhile, administration of miR-124 inhibitor attenuated the protective effects of FA. The present study suggests that FA attenuates LPS-induced adhesion and migration of monocytes to type II alveolar epithelial cells though upregulating miR-124, thereby inhibiting the expression of CCL2. These findings indicate that the potential application of FA is promising and that miR-124 mimics could also be used in the treatment of ALI.

Protective effect of Chrysanthemum morifolium Ramat. ethanol extract on lipopolysaccharide induced acute lung injury in mice

BACKGROUND

To evaluate the effect of Chrysanthemum morifolium Ramat. ethanol extract (CEE) on lipopolysaccharide induced acute lung injury in mice.

METHODS

The ninety C57BL/6 J male mice randomly divided into five groups: control, model and CEE (50, 100, 200 mg/kg) groups for 7 days oral administration. At the last administration, all mice except control were intratracheal instilled with lipopolysaccharide (LPS, 3 mg/kg) for establish the acute lung injury. Then lung histopathologic, lung wet/dry weight, white blood cells, lymphocytes, neutrophils were detected. The pro-inflammation cytokine tumor necrosis factor-α (TNF-α), interleukin (IL)-6, anti-inflammatory cytokine transforming growth factor-β1 (TGF-β1), IL-10 and the marker of antioxides ability total-antioxidant capacity (T-AOC), malondialdehyde (MDA) in lung tissue were measured.

RESULTS

The result showed that CEE could improve lung histopathological injury, reduce the ratio of wet/dry lung weight and lung index, inhibit the increased number of white blood cells, lymphocytes and neutrophils, and reduce the increased levels of TNF-α and IL-6. While CEE also significantly increased the levels of TGF-β1 and IL-10. Furthermore, CEE also markedly increased the activity of T-AOC, and decreased the contents of MDA with a dose-dependent manner.

CONCLUSIONS

The study exhibited that CEE has a potential protective effect on lipopolysaccharide induced acute lung injury in mice, the action mechanism of CEE may through balance of the pro-inflammatory and anti-inflammatory factors, and the oxygen free radicals inhibition.

Mesenchymal stromal/stem cells modulate response to experimental sepsis-induced lung injury via regulation of miR-27a-5p in recipient mice

Introduction

Mesenchymal stromal cell (MSC) therapy mitigates lung injury and improves survival in murine models of sepsis. Precise mechanisms of therapeutic benefit remain poorly understood.

Objectives

To identify host-derived regulatory elements that may contribute to the therapeutic effects of MSCs, we profiled the microRNAome (miRNAome) and transcriptome of lungs from mice randomised to experimental polymicrobial sepsis-induced lung injury treated with either placebo or MSCs.

Methods and results

A total of 11 997 genes and 357 microRNAs (miRNAs) expressed in lungs were used to generate a statistical estimate of association between miRNAs and their putative mRNA targets; 1395 miRNA:mRNA significant association pairs were found to be differentially expressed (false discovery rate ≤0.05). MSC administration resulted in the downregulation of miR-27a-5p and upregulation of its putative target gene VAV3 (adjusted p=1.272E-161) in septic lungs. In human pulmonary microvascular endothelial cells, miR-27a-5p expression levels were increased while VAV3 was decreased following lipopolysaccharide (LPS) or tumour necrosis factor (TNF) stimulation. Transfection of miR-27a-5p mimic or inhibitor resulted in increased or decreased VAV3 message, respectively. Luciferase reporter assay demonstrated specific binding of miR-27a-5p to the 3′UTR of VAV3. miR27a-5p inhibition mitigated TNF-induced (1) delayed wound closure, increased (2) adhesion and (3) transendothelial migration but did not alter permeability. In vivo, cell infiltration was attenuated by intratracheal coinstillation of the miR-27a-5p inhibitor, but this did not protect against endotoxin-induced oedema formation.

Conclusions

Our data support involvement of miR-27a-5p and VAV3 in cellular adhesion and infiltration during acute lung injury and a potential role for miR-27a-based therapeutics for acute respiratory distress syndrome.

Alveolar Type 2 Epithelial Cells as Potential Therapeutics for Acute Lung Injury/Acute Respiratory Distress Syndrome

Acute lung injury/acute respiratory distress syndrome is a common clinical illness with high morbidity and mortality, which is still one of the medical problems urgently needed to be solved. Alveolar type 2 epithelial cells are an important component of lung epithelial cells and as a kind of stem cells, they can proliferate and differentiate into alveolar type 1 epithelial cells, thus contributing to lung epithelial repairment. In addition, they synthesize and secrete all components of the surfactant that regulates alveolar surface tension in the lungs. Moreover, alveolar type 2 epithelial cells play an active role in enhancing alveolar fluid clearance and reducing lung inflammation. In recent years, as more advanced approaches appear in the field of stem and progenitor cells in the lung, many preclinical studies have shown that the cell therapy of alveolar type 2 epithelial cells has great potential effects for acute lung injury/acute respiratory distress syndrome. We reviewed the recent progress on the mechanisms of alveolar type 2 epithelial cells involved in the damaged lung repairment, aiming to explore the possible therapeutic targets in acute lung injury/acute respiratory distress syndrome.

Mesenchymal Stem/Stromal Cell Production Compliant with Good Manufacturing Practice: Comparison between Bone Marrow, the Gold Standard Adult Source, and Wharton's Jelly, an Extraembryonic Source

Many clinical trials report mesenchymal stem/stromal cells (MSCs) efficacy in various indications. Therefore, standardization of MSC production becomes necessary. MSC properties are impacted by tissue origin, especially if they are from extraembryonic tissue or adult sources. For this reason, we evaluated the impact of MSC tissue origin on production. Methods: Three productions of MSC from Wharton’s Jelly (WJ) or from bone marrow (BM) were performed according to good manufacturing practice. The identity (phenotype, differentiation, and clonogenic capacities), safety (karyotype, telomerase activity, sterility, and donor qualification), and functionality (viability, mixed lymphocyte reaction) of each cell batch were analyzed. Results: Slight differences between MSC sources were observed for phenotype, telomerase activity, and clonogenic capacities. Conclusion: Both sources have made it possible to quickly and easily obtain clinical grade MSC. However, as availability of the source is thought to be essential, WJ seems more advantageous than BM.

Liang-Ge-San, a Classic Traditional Chinese Medicine Formula, Attenuates Lipopolysaccharide-Induced Acute Lung Injury Through Up-Regulating miR-21

Background: Acute lung injury (ALI) is a life-threatening disease without effective chemotherapy at present. Liang-Ge-San (LGS) is a famous traditional Chinese medicine formula, which is used to treat ALI in China. However, only a few studies have addressed the mechanisms of LGS in ALI. Purpose: To evaluate the anti-inflammatory effects of LGS on lipopolysaccharide (LPS)-induced ALI, and to explore its underlying molecular mechanism. Methods: Murine RAW264.7 cells were treated with LGS and LPS (1 μg/ml). The generation of IL-6, TNF-α, IL-1β was detected by ELISA. The protein expressions of STAT3 and P-STAT3 (Tyr705) were determined by Western blotting and fluorescence confocal microscopy. STAT3 transcriptional activity was investigated by luciferase reporter gene assay. qPCR was used to detect the expressions of microRNA-21 (miR-21), STAT3, and IL-6. DSS cross-linking assay was used to assess the change of STAT3 dimer. In vivo anti-inflammatory effects of LGS were evaluated in an ALI mouse model induced by tracheal instillation of LPS (3 mg/kg). The anti-ALI effects were evaluated by ELISA, qPCR, Western blotting, BCA, and H&E assays. Results: LGS suppressed LPS-stimulated IL-6, TNF-α, and IL-1β generation in murine macrophages RAW264.7. Moreover, LGS down-regulated protein levels of P-STAT3 (Tyr705) and STAT3, inhibited STAT3 transcriptional activity, and up-regulated miR-21. Furthermore, blockage of miR-21 antagonized the inhibitory effects of LGS on the production of IL-6 and the expressions of P-STAT3 (Tyr705) and STAT3 as well as the formation of STAT3 dimer. Critically, LGS up-regulated the expression of miR-21 and inhibited the protein expressions of STAT3 and P-STAT3 (Tyr705) to reduce the release of IL-6 and inflammatory cell infiltration as well as the degree of edema in LPS-induced ALI mice. Conclusion: LGS inhibited LPS-induced ALI through up-regulating miR-21 and subsequently inhibiting the STAT3 signaling pathway, thereby decreasing the release of IL-6.

3-Dehydroandrographolide protects against lipopolysaccharide-induced inflammation through the cholinergic anti-inflammatory pathway

Acute lung injury (ALI) is a deadly disease without effective chemotherapy, so far. Traditional Chinese medicine andrographis herba is frequently used in the treatment of respiratory diseases. In searching for natural anti-ALI components from andrographis herba, the activities of 3-dehydroandrographolide (3-DA), a new natural andrographolide product from andrographis herba were evaluated. In this study, murine macrophage RAW 264.7 cells and BALB/c mice were treated with LPS (lipopolysaccharide, 100 ng/ml in vitro; 3 mg/kg, intratracheal) to establish inflammation models. 3-DA attenuated the release of pro-inflammatory cytokines IL-6 and TNF-α, inhibited the degradation and phosphorylation of IκBα, and suppressed the nuclear translocation of NF-κB p65 as well as the phosphorylation of Akt at Ser473 in LPS-stimulated RAW 264.7 macrophage cells. Furthermore, 3-DA increased α7nAchR expression level and bound with α7nAchR. More importantly, the anti-inflammatory effects of 3-DA were counteracted in the presence of α7nAchR siRNA or methyllycaconitine (MLA, a α7nAchR specific inhibitor), suggesting that α7nAchR is a potential target in the anti-inflammatory effects of 3-DA. Besides, 3-DA significantly inhibited inflammation in LPS-induced ALI mice, which was associated with the decrease of lung water content and inflammatory cytokines, the inhibition of neutrophil and macrophage infiltration, and activation of the NF-κB/Akt signaling pathway. Moreover, these protective effects were attenuated by the treatment of MLA. Taken together, 3-DA alleviates LPS-induced inflammation via the cholinergic anti-inflammatory pathway in vitro and in vivo. These findings provide a rationale for the role of the cholinergic anti-inflammatory pathway in inflammation and the promising clinical application of 3-DA to treat ALI.

Mesenchymal stem cells: A double-edged sword in radiation-induced lung injury

Radiation therapy is an important treatment modality for multiple thoracic malignancies. However, radiation‐induced lung injury (RILI), which is the term generally used to describe damage to the lungs caused by exposure to ionizing radiation, remains a critical issue affecting both tumor control and patient quality of life. Despite tremendous effort, there is no current consensus regarding the optimal treatment approach for RILI. Because of a number of functional advantages, including self‐proliferation, multi‐differentiation, injury foci chemotaxis, anti‐inflammation, and immunomodulation, mesenchymal stem cells (MSCs) have been a focus of research for many years. Accumulating evidence indicates the therapeutic potential of transplantation of MSCs derived from adipose tissue, umbilical cord blood, and bone marrow for inflammatory diseases, including RILI. However, reports have also shown that MSCs, including fibrocytes, lung hematopoietic progenitor cells, and ABCG²⁺ MSCs, actually enhance the progression of lung injuries. These contradictory results suggest that MSCs may have dual effects and that caution should be taken when using MSCs to treat RILI. In this review, we present and discuss recent evidence of the double‐edged function of MSCs and provide comments on the prospects of these findings.

Manufacturing Differences Affect Human Bone Marrow Stromal Cell Characteristics and Function: Comparison of Production Methods and Products from Multiple Centers

Human bone marrow stromal cells (BMSCs, also known as bone marrow-derived mesenchymal stem cells) are manufactured using many different methods, but little is known about the spectrum of manufacturing methods used and their effects on BMSC characteristics and function. Seven centers using, and one developing, Good Manufacturing Practices (GMP) processes were surveyed as to their production methods. Among the seven centers, all used marrow aspirates as the starting material, but no two centers used the same manufacturing methods. Two to four BMSC lots from each center were compared using global gene expression. Among the twenty-four BMSC lots from the eight centers intra-center transcriptome variability was low and similar among centers. Principal component analysis and unsupervised hierarchical clustering analysis separated all the lots from five centers into five distinct clusters. BMSCs from six of the eight centers were tested for their ability to form bone and support hematopoiesis by in vivo transplantation (defining features of BMSCs). Those from all six centers tested formed bone, but the quantity formed was highly variable and BMSCs from only three centers supported hematopoiesis. These results show that differences in manufacturing resulted in variable BMSC characteristics including their ability to form bone and support hematopoiesis.

Adipose-Derived Mesenchymal Stem Cells for Treatment of Airway Injuries in A Patient after Long-Term Exposure to Sulfur Mustard

OBJECTIVE

Sulfur mustard (SM) is a potent mutagenic agent that targets several organs, particularly lung tissue. Changes in morphological structure of the airway system are associated with chronic obstructive pulmonary deficiency following exposure to SM. Although numerous studies have demonstrated pathological effects of SM on respiratory organs, unfortunately there is no effective treatment to inhibit further respiratory injuries or induce repair in these patients. Due to the extensive progress and achievements in stem cell therapy, we have aimed to evaluate safety and potential efficacy of systemic mesenchymal stem cell (MSC) administration on a SM-exposed patient with chronic lung injuries.

MATERIALS AND METHODS

In this clinical trial study, our patient received 100×106cells every 20 days for 4 injections over a 2-month period. After each injection we evaluated the safety, pulmonary function tests (PFT), chronic obstructive pulmonary disease (COPD) Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), Borg Scale Dyspnea Assessment (BSDA), and 6 Minute Walk Test (6MWT). One-way ANOVA test was used in this study which was not significant (P>0.05).

RESULTS

There were no infusion toxicities or serious adverse events caused by MSC administration. Although there was no significant difference in PFTs, we found a significant improvement for 6MWT, as well as BSDA, SGRQ, and CAT scores after each injection.

CONCLUSION

Systemic MSC administration appears to be safe in SM-exposed patients with moderate to severe injuries and provides a basis for subsequent cell therapy investigations in other patients with this disorder (Registration Number: IRCT2015110524890N1).

Salidroside Protects Lipopolysaccharide-Induced Acute Lung Injury in Mice

Salidroside (SDS) has been reported to have anti-inflammatory properties. The objective of this study was to investigate the protective effect of SDS on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. BALB/c mice were pretreated with SDS 1 hour before intranasal instillation of LPS. Seven hours after LPS administration, the myeloperoxidase in histology of lungs, lung wet/dry ratio, and inflammatory cells in the bronchoalveolar lavage fluid (BALF) were determined. The levels of pro-inflammatory cytokines, tumor necrosis factor α (TNF-α), interleukin-1β (IL 1β), and IL-6 in the BALF were measured by enzyme-linked immunosorbent assay. The expression of Toll-like receptor 4 (TLR4), inhibitor of nuclear factor-kappa B (IκB-α), and nuclear factor-kappa B (NF-κB) p65 was detected by Western blot. The SDS reduced the inflammatory cells in BALF, decreased the wet/dry ratio of lungs, attenuated the LPS-induced histological alterations in the lung, and inhibited the production of TNF-α, IL-1β, and IL-6. Western blot showed that SDS efficiently inhibited the phosphorylation of IκB-α, p65 NF-κB, and the expression of TLR4. These data show that the anti-inflammatory effects of SDS (at least 20 mg/kg) against LPS-induced ALI due to its ability to inhibit TLR4 mediated the NF-κB signaling pathways. The SDS may represent a novel strategy for treating LPS-induced ALI.

The Devil Is in the Details: Incomplete Reporting in Preclinical Animal Research

Incomplete reporting of study methods and results has become a focal point for failures in the reproducibility and translation of findings from preclinical research. Here we demonstrate that incomplete reporting of preclinical research is not limited to a few elements of research design, but rather is a broader problem that extends to the reporting of the methods and results. We evaluated 47 preclinical research studies from a systematic review of acute lung injury that use mesenchymal stem cells (MSCs) as a treatment. We operationalized the ARRIVE (Animal Research: Reporting of In Vivo Experiments) reporting guidelines for pre-clinical studies into 109 discrete reporting sub-items and extracted 5,123 data elements. Overall, studies reported less than half (47%) of all sub-items (median 51 items; range 37-64). Across all studies, the Methods Section reported less than half (45%) and the Results Section reported less than a third (29%). There was no association between journal impact factor and completeness of reporting, which suggests that incomplete reporting of preclinical research occurs across all journals regardless of their perceived prestige. Incomplete reporting of methods and results will impede attempts to replicate research findings and maximize the value of preclinical studies.

Human Influenza Virus Infections

Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.

Human Influenza Virus Infections

Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.

Mesenchymal Stem Cells after Polytrauma: Actor and Target

Mesenchymal stem cells (MSCs) are multipotent cells that are considered indispensable in regeneration processes after tissue trauma. MSCs are recruited to damaged areas via several chemoattractant pathways where they function as “actors” in the healing process by the secretion of manifold pro- and anti-inflammatory, antimicrobial, pro- and anticoagulatory, and trophic/angiogenic factors, but also by proliferation and differentiation into the required cells. On the other hand, MSCs represent “targets” during the pathophysiological conditions after severe trauma, when excessively generated inflammatory mediators, complement activation factors, and damage- and pathogen-associated molecular patterns challenge MSCs and alter their functionality. This in turn leads to complement opsonization, lysis, clearance by macrophages, and reduced migratory and regenerative abilities which culminate in impaired tissue repair. We summarize relevant cellular and signaling mechanisms and provide an up-to-date overview about promising future therapeutic MSC strategies in the context of severe tissue trauma.

Human Mesenchymal Stem Cells Genetically Engineered to Overexpress Brain-derived Neurotrophic Factor Improve Outcomes in Huntington's Disease Mouse Models

Huntington's disease (HD) is a fatal degenerative autosomal dominant neuropsychiatric disease that causes neuronal death and is characterized by progressive striatal and then widespread brain atrophy. Brain-derived neurotrophic factor (BDNF) is a lead candidate for the treatment of HD, as it has been shown to prevent cell death and to stimulate the growth and migration of new neurons in the brain in transgenic mouse models. BDNF levels are reduced in HD postmortem human brain. Previous studies have shown efficacy of mesenchymal stem/stromal cells (MSC)/BDNF using murine MSCs, and the present study used human MSCs to advance the therapeutic potential of the MSC/BDNF platform for clinical application. Double-blinded studies were performed to examine the effects of intrastriatally transplanted human MSC/BDNF on disease progression in two strains of immune-suppressed HD transgenic mice: YAC128 and R6/2. MSC/BDNF treatment decreased striatal atrophy in YAC128 mice. MSC/BDNF treatment also significantly reduced anxiety as measured in the open-field assay. Both MSC and MSC/BDNF treatments induced a significant increase in neurogenesis-like activity in R6/2 mice. MSC/BDNF treatment also increased the mean lifespan of the R6/2 mice. Our genetically modified MSC/BDNF cells set a precedent for stem cell-based neurotherapeutics and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis, Alzheimer's disease, and some forms of Parkinson's disease. These cells provide a platform delivery system for future studies involving corrective gene-editing strategies.

Stem/progenitor cells in endogenous repairing responses: new toolbox for the treatment of acute lung injury

The repair of organs and tissues has stepped into a prospective era of regenerative medicine. However, basic research and clinical practice in the lung regeneration remains crawling. Owing to the complicated three dimensional structures and above 40 types of pulmonary cells, the regeneration of lung tissues becomes a great challenge. Compelling evidence has showed that distinct populations of intrapulmonary and extrapulmonary stem/progenitor cells can regenerate epithelia as well as endothelia in various parts of the respiratory tract. Recently, the discovery of human lung stem cells and their relevant studies has opened the door of hope again, which might put us on the path to repair our injured body parts, lungs on demand. Herein, we emphasized the role of endogenous and exogenous stem/progenitor cells in lungs as well as artificial tissue repair for the injured lungs, which constitute a marvelous toolbox for the treatment of acute lung injury. Finally, we further discussed the potential problems in the pulmonary remodeling and regeneration.

Systematic review and meta-analysis of efficacy of mesenchymal stem cells on locomotor recovery in animal models of traumatic brain injury

Introduction

The therapeutic potential of mesenchymal stem cells (MSCs) for traumatic brain injury (TBI) is attractive. Conducting systematic review and meta-analyses based on data from animal studies can be used to inform clinical trial design. To conduct a systematic review and meta-analysis to (i) systematically review the literatures describing the effect of MSCs therapy in animal models of TBI, (ii) determine the estimated effect size of functional locomotor recovery after experimental TBI, and (iii) to provide empirical evidence of biological factors associated with greater efficacy.

Methods

We conducted a systematic search of PubMed, EMBASE, and Web of Science and hand searched related references. Studies were selected if they reported the efficacy of MSCs in animal models of TBI. Two investigators independently assessed the identified studies. We extracted the details of individual study characteristics from each publication, assessed study quality, evaluated the effect sizes of MSCs treatment, and performed stratified meta-analysis and meta-regression, to assess the influence of study design on the estimated effect size. The presence of small effect sizes was investigated using funnel plots and Egger’s tests.

Results

Twenty-eight eligible controlled studies were identified. The study quality was modest. Between-study heterogeneity was large. Meta-analysis showed that MSCs exert statistically significant positive effects on sensorimotor and neurological motor function. For sensorimotor function, maximum effect size in studies with a quality score of 5 was found in the weight-drop impact injury TBI model established in male SD rats, to which syngeneic umbilical cord-derived MSCs intracerebrally at cell dose of (1–5) × 10⁶ was administered r 6 hours following TBI, using ketamine as anesthetic agent. For neurological motor function, effect size was maximum for studies with a quality score of 5, in which the weight-drop impact injury TBI models of the female Wistar rats were adopted, with administration syngeneic bone marrow-derived MSCs intravenously at cell dose of 5 × 10⁶ at 2 months after TBI, using sevofluorane as anesthetic agent.

Conclusions

We conclude that MSCs therapy may improve locomotor recovery after TBI. However, additional well-designed and well-reported animal studies are needed to guide further clinical studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0034-0) contains supplementary material, which is available to authorized users.

Specific subsets of mesenchymal stroma cells to treat lung disorders--finding the Holy Grail

Accumulating studies, both in animals and human clinical trials with mesenchymal stroma cells (MSC) support the hypothesis of therapeutic effects of these cells in various disorders. However, despite success in immune-mediated disorders such as Crohns' disease, lung disorders such as chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary disease (IPF) treated with MSC have so far not yielded a revolutionary effect on clinical symptoms. Promising data on immunomodulatory effects in COPD have kept nourishing the research into finding specific traits of MSC beneficial in disease. A heterogeneous population of injected cells might drown a potential therapeutic role of a specific group of MSC. Thus careful analysis of MSC regarding their molecular capabilities such as delivering specific therapeutic vesicles to the environment, or plain cytokine/chemokine fingerprinting might prove useful in augmenting therapies against lung diseases.