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.

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.

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.

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.

Human adipose-derived stem cells impair natural killer cell function and exhibit low susceptibility to natural killer-mediated lysis.

Human adipose-derived stem cells (hASCs) have been successfully used in treating numerous diseases. However, several aspects need to be considered, particularly in the context of allogeneic cell therapy. To better understand hASCs-host interactions, we studied the phenotype of hASCs and their modulatory effect on natural killer (NK) cells by using bone marrow-mesenchymal stem cells (hBM-MSCs) as a reference.

A population of CD19highCD45R-/lowCD21low B lymphocytes poised for spontaneous secretion of IgG and IgA antibodies.

Ab responses to selected Ags are produced by discrete B cell populations whose presence and functional relevance vary along the ontogeny. The earliest B lineage-restricted precursors in gestational day 11 mouse embryos display the CD19(+)CD45R/B220(-) phenotype. Phenotypically identical cells persist throughout gestation and in postnatal life, in parallel to the later-arising, CD19(+)CD45R(+) B cells.