Locally applied mesenchymal stromal cells (MSCs) have the capacity to promote the healing of perianal fistulas in Crohn's disease (CD) and are under clinical development for the treatment of... Show moreLocally applied mesenchymal stromal cells (MSCs) have the capacity to promote the healing of perianal fistulas in Crohn's disease (CD) and are under clinical development for the treatment of proctitis in ulcerative colitis (UC). Despite these clinical advances, the mechanism of action of local MSC therapy in inflammatory bowel disease (IBD) is largely unknown. We hypothesized that the local cytokine environment in IBD patients affects the immunomodulatory properties of MSCs. To evaluate this, 11 cytokines were analyzed in inflamed tissues obtained from CD and UC patients. Based on the identified cytokine profiles 4 distinct cytokine mixtures that mimic various inflammatory IBD environments were established. Next, MSCs were cultured in the presence of either of these 4 cytokine mixtures after which the expression of immunomodulatory and tissue regenerative molecules and the capacity of MSCs to modulate T-cell proliferation and dendritic cell (DC) differentiation were assessed. Our data show that MSCs respond, in a cytokine-specific manner, by upregulation of immunomodulatory and tissue regenerative molecules, including cyclooxygenase-2, indoleamine 2,3-dioxygenase, and transforming growth factor-beta 1. Functional studies indicate that MSCs exposed to a cytokine profile mimicking one of the 2 UC cytokine milieus were less effective in inhibition of DC differentiation. In conclusion, our data indicate that cytokine mixes mimicking the local cytokine milieus of inflamed UC colonic or CD fistulas tissues can differentially affect the immunomodulatory and tissue regenerative characteristics of MSCs. These data support the hypothesis that the local intestinal cytokine milieu serves as a critical factor in the efficacy of local MSC treatment. Show less
Helm, D. van der; Barnhoorn, M.C.; Jonge-Muller, E.S.M. de; Molendijk, I.; Hawinkels, L.J.A.C.; Coenraad, M.J.; ... ; Verspaget, H.W. 2019
Hematopoietic stem cell transplantation (HSCT) and mesenchymal stromal (MSC) cell therapy are currently under investigation as novel therapies for inflammatory bowel diseases (IBD). Hematopoietic... Show moreHematopoietic stem cell transplantation (HSCT) and mesenchymal stromal (MSC) cell therapy are currently under investigation as novel therapies for inflammatory bowel diseases (IBD). Hematopoietic stem cells are thought to repopulate the immune system and reset the immunological response to luminal antigens. MSCs have the capacity to differentiate into a wide variety of distinct cell lineages and to suppress immune responses in vitro and in vivo. The main goal of this thesis was to study the safety, feasibility, and applicability of stem cell therapy in IBD. Chapter 2 concludes that autologous HSCT appears to be safe and can be an alternative strategy for Crohn__s disease patients with severe and therapy resistant disease. Data from the phase I study described in Chapter 3 demonstrates that MSCs isolated from Crohn__s disease patients have similar characteristics compared to MSCs from healthy donors and that administration of autologous bone marrow derived MSCs appears to be safe and feasible in the treatment of refractory Crohn__s disease. Chapter 4 shows that MSC phenotype and function are not affected by therapeutic concentrations of drugs commonly used in the treatment of IBD. Chapter 5 demonstrates that IFN-_ activation of MSCs increases their immunosuppresive capacities and importantly, their therapeutic efficacy in vivo. Show less