Human adipose mesenchymal stem cells modulate myeloid cells toward an anti-inflammatory and reparative phenotype: role of IL-6 and PGE2.

Background: Mesenchymal stem cells (MSCs) activate the endogenous immune regulatory system, inducing a therapeutic effect in recipients. MSCs have demonstrated the ability to modulate the differentiation of myeloid cells toward a phagocytic and anti-inflammatory profile. Allogeneic, adipose-derived MSCs (ASCs) have been investigated for the management of complex perianal fistula, with darvadstrocel being the first ASC therapy approved in Europe in March 2018.

Role of tissue factor in the procoagulant and antibacterial effects of human adipose-derived mesenchymal stem cells during pneumosepsis in mice.

Background: Adult mesenchymal stem cells (MSCs) improve the host response during experimental sepsis in animals. MSCs from various sources express a procoagulant activity that has been linked to the expression of tissue factor. This study sought to determine the role of tissue factor associated with adipose-derived MSCs (ASCs) in their procoagulant and antibacterial effects during pneumonia-derived sepsis.

Dissecting Allo-Sensitization After Local Administration of Human Allogeneic Adipose Mesenchymal Stem Cells in Perianal Fistulas of Crohn's Disease Patients.

Adipose mesenchymal stem cells (ASC) are considered minimally immunogenic. This is due to the low expression of human leukocyte antigens I (HLA-I), lack of HLA-II expression and low expression of co-stimulatory molecules such as CD40 and CD80. The low rate of observed immunological rejection as well as the immunomodulatory qualities, position ASC as a promising cell-based therapy for the treatment of a variety of inflammatory indications.

Human Adipose-Derived Mesenchymal Stem Cells Modify Lung Immunity and Improve Antibacterial Defense in Pneumosepsis Caused by Klebsiella pneumoniae.

Adult mesenchymal stem cells exert immunomodulatory effects that might improve the host response during sepsis. Knowledge on the effect of adipose-derived mesenchymal stem cells (ASCs) in sepsis is limited. Klebsiella (K.

Human cardiac stem cells inhibit lymphocyte proliferation through paracrine mechanisms that correlate with indoleamine 2,3-dioxygenase induction and activity.

Transplantation of allogeneic human cardiac/stem progenitor cells (hCSCs) is currently being tested in several phase I/II clinical trials as a novel and promising therapy for restoration of myocardial tissue function in acute myocardial infarction (AMI) patients. Previous findings demonstrate that these cells have an immune suppressive profile interacting with different populations from the immune system, resulting in overall attenuation of myocardial inflammation. However, transplanted hCSCs are still recognized and cleared from the injured site, impairing long retention times in the tissue that could translate into a higher clinical benefit.

Intravenous Infusion of Human Adipose Mesenchymal Stem Cells Modifies the Host Response to Lipopolysaccharide in Humans: A Randomized, Single-Blind, Parallel Group, Placebo Controlled Trial.

In experimental models, mesenchymal stem cells (MSCs) can modulate various immune responses implicated in the pathogenesis of sepsis. Intravenous injection of lipopolysaccharide (LPS) into healthy subjects represents a model with relevance for the host response to sepsis. To explore the use of MSCs in sepsis, we determined their effect on the response to intravenous LPS in a randomized study in 32 healthy subjects with four treatment arms: placebo or allogeneic adipose MSCs (ASCs) intravenously at either 0.

Comparative Analysis between the In Vivo Biodistribution and Therapeutic Efficacy of Adipose-Derived Mesenchymal Stromal Cells Administered Intraperitoneally in Experimental Colitis.

Mesenchymal stem cells (MSCs) have emerged as a promising treatment for inflammatory diseases. The immunomodulatory effect of MSCs takes place both by direct cell-to-cell contact and by means of soluble factors that leads to an increased accumulation of regulatory immune cells at the sites of inflammation. Similar efficacy of MSCs has been described regardless of the route of administration used, the inflammation conditions and the major histocompatibility complex context.

Human Cardiac-Derived Stem/Progenitor Cells Fine-Tune Monocyte-Derived Descendants Activities toward Cardiac Repair.

Cardiac repair following MI relies on a finely regulated immune response involving sequential recruitment of monocytes to the injured tissue. Monocyte-derived cells are also critical for tissue homeostasis and healing process. Our previous findings demonstrated the interaction of T and natural killer cells with allogeneic human cardiac-derived stem/progenitor cells (hCPC) and suggested their beneficial effect in the context of cardiac repair.

Biodistribution and Efficacy of Human Adipose-Derived Mesenchymal Stem Cells Following Intranodal Administration in Experimental Colitis.

Mesenchymal stem cells (MSCs) have a large potential in cell therapy for treatment of inflammatory and autoimmune diseases, thanks to their immunomodulatory properties. The encouraging results in animal models have initiated the translation of MSC therapy to clinical trials. In cell therapy protocols with MSCs, administered intravenously, several studies have shown that a small proportion of infused MSCs can traffic to the draining lymph nodes (LNs).

Intralymphatic Administration of Adipose Mesenchymal Stem Cells Reduces the Severity of Collagen-Induced Experimental Arthritis.

Mesenchymal stem cells (MSCs) are multipotent stromal cells with immunomodulatory properties. They have emerged as a very promising treatment for autoimmunity and inflammatory diseases such as rheumatoid arthritis. Previous studies have demonstrated that MSCs, administered systemically, migrate to lymphoid tissues associated with the inflammatory site where functional MSC-induced immune cells with a regulatory phenotype were increased mediating the immunomodulatory effects of MSCs.

Identification of Potential Plasma microRNA Stratification Biomarkers for Response to Allogeneic Adipose-Derived Mesenchymal Stem Cells in Rheumatoid Arthritis.

The ability to identify and stratify patients that will respond to specific therapies has been transformational in a number of disease areas, particularly oncology. It is anticipated that this will also be the case for cell-based therapies, particularly in complex and heterogeneous diseases such as rheumatoid arthritis (RA). Recently, clinical results with expanded allogenic adipose-derived mesenchymal stem cells (eASCs) have indicated clinical efficacy in highly refractory RA patients.

Adipose-derived mesenchymal stromal cells modulate experimental autoimmune arthritis by inducing an early regulatory innate cell signature.

Modulation of innate immune responses in rheumatoid arthritis and other immune-mediated disorders is of critical importance in the clinic since a growing body of information has shown the key contribution of dysregulated innate responses in the progression of the disease. Mesenchymal stromal cells (MSCs) are the focus of intensive efforts worldwide due to their key role in tissue regeneration and modulation of inflammation. In this study, we define innate immune responses occurring during the early course of treatment with a single dose of expanded adipose-derived MSCs (eASCs) in established collagen-induced arthritis.

T Lymphocyte Prestimulation Impairs in a Time-Dependent Manner the Capacity of Adipose Mesenchymal Stem Cells to Inhibit Proliferation: Role of Interferon γ, Poly I:C, and Tryptophan Metabolism in Restoring Adipose Mesenchymal Stem Cell Inhibitory Effect.

The immunomodulatory properties of mesenchymal stem/stromal cells (MSCs) make them an attractive therapeutic tool to treat chronic inflammatory diseases, such as rheumatoid arthritis or Crohn's disease. These indications are characterized by a chronic activation of immune cells that perpetuates the disease. In vitro, when adipose mesenchymal stem cells (ASCs) are cultured with T lymphocytes at the time of stimulation, their proliferation is inhibited.

Mesenchymal stem cells as a therapeutic tool to treat sepsis.

Sepsis is a clinical syndrome caused by a deregulated host response to an infection. Sepsis is the most frequent cause of death in hospitalized patients. Although knowledge of the pathogenesis of sepsis has increased substantially during the last decades, attempts to design effective and specific therapies targeting components of the derailed host response have failed.

Survival and biodistribution of xenogenic adipose mesenchymal stem cells is not affected by the degree of inflammation in arthritis.

Background: Application of mesenchymal stem/stromal cells (MSCs) in treating different disorders, in particular osteo-articular diseases, is currently under investigation. We have already documented the safety of administrating human adipose tissue-derived stromal MSCs (hASCs) in immunodeficient mice. In the present study, we investigated whether the persistence of MSC is affected by the degree of inflammation and related to the therapeutic effect in two inflammatory models of arthritis.

Immunomodulatory Potential of Human Adipose Mesenchymal Stem Cells Derived Exosomes on in vitro Stimulated T Cells.

In the recent years, it has been demonstrated that the biological activity of mesenchymal stem cells (MSCs) is mediated through the release of paracrine factors. Many of these factors are released into exosomes, which are small membranous vesicles that participate in cell-cell communication. Exosomes from MSCs are thought to have similar functions to MSCs such as repairing and regeneration of damaged tissue, but little is known about the immunomodulatory effect of these vesicles.

Human adipose tissue-derived mesenchymal stromal cells promote B-cell motility and chemoattraction.

Background Aims: Mesenchymal stromal cells hold special interest for cell-based therapy because of their tissue-regenerative and immunosuppressive abilities. B-cell involvement in chronic inflammatory and autoimmune pathologies makes them a desirable target for cell-based therapy. Mesenchymal stromal cells are able to regulate B-cell function; although the mechanisms are little known, they imply cell-to-cell contact.

Tryptophan concentration is the main mediator of the capacity of adipose mesenchymal stromal cells to inhibit T-lymphocyte proliferation in vitro.

Background Aims: Mesenchymal stromal cells (MSCs) have immunomodulatory properties that are mediated by cell-to-cell interactions and paracrine effects through soluble factors, among which tryptophan (Trp) conversion into kynurenine (Kyn) through the enzymatic activity of indoleamine 2,3-dioxygenase has been proven to be of special relevance. However, the respective role of Trp depletion and/or Kyn accumulation on the inhibition of T-cell proliferation by MSCs remains unclear.

Methods: The effect of supplementation with increasing concentrations of Trp on the capacity of MSCs to inhibit T-lymphocyte proliferation in vitro was investigated.

White paper on how to go forward with cell-based advanced therapies in Europe.

The current White paper summarizes the discussions and exchange of experiences during the first European Interdisciplinary Summit on Cell-Based ATMPs held in Vienna, Austria, May 02-03, 2013. The meeting was supported by the Research Networking Programme REMEDIC (regenerative medicine) funded by the European Science Foundation and by the British Medical Research Council. To improve the competitiveness of Europe in the field of cell-based Advanced Medicinal Therapy Products (ATMPs), the following key issues were identified during the meeting: removal of national hurdles in the European Union, harmonization of national and subnational differences in Hospital Exemption rules, improved treatment algorithms for reimbursement, better knowledge on the mode of action, predictive preclinical efficacy and safety testing, need for innovative systems for preclinical testing, appropriate product characterization, manufacturing with cost of goods in mind, and appropriate design of clinical trials.

Adipose mesenchymal stromal cell function is not affected by methotrexate and azathioprine.

Given their capacity to modulate the immune response, adipose mesenchymal stem or stromal cells (ASCs) have been used as therapeutic tools to treat chronic inflammatory and autoimmune diseases both in preclinical and clinical studies. Patients enrolled in such clinical trials are often concomitantly treated with immunomodulatory drugs such as methotrexate (MTX) or azathioprine (AZA). Therefore it is necessary to investigate the possible impact of these drugs on ASC function to learn if there are any interactions that would affect the therapeutic effects of either component and thus the clinical outcome of the trials.

Toll-like receptors as modulators of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) have differentiation and immunomodulatory properties that make them interesting tools for the treatment of degenerative disorders, allograft rejection, or inflammatory and autoimmune diseases. Biological properties of MSCs can be modulated by the inflammatory microenvironment they face at the sites of injury or inflammation. Indeed, MSCs do not constitutively exert their immunomodulating properties but have to be primed by inflammatory mediators released from immune cells and inflamed tissue.

Mesenchymal stem cells as therapeutic agents of inflammatory and autoimmune diseases.

Interest and expectations on therapies based on adult mesenchymal stem/stromal cells (MSCs) for inflammatory and autoimmune diseases have remarkably grown in recent years, supported by encouraging data demonstrating their immunomodulatory properties and therapeutic effects in experimental animal models. Despite extensive research, our knowledge on areas of importance for their clinical use such as the mechanism/s of action, the route, dosing and timing of administration, the cell fate and distribution in vivo, the safety and efficacy of allogeneic MSCs treatments, remain insufficient. A better understanding of MSCs biology is required to ensure that the therapeutic efficacy, as observed in animal models, can be successfully translated in clinical trials.

Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair: International Cartilage Repair Society Recommendations Based on Current Scientific Evidence and Standards of Clinical Care.

Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products.

Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field.