Synergismus zwischen Mycofenolatmofetil und mesenchymalen Stammzellen in einem F1-Maus-Model

Organtransplantationen stellen für viele Erkrankungen, die mit dem endgültigen Funktionsverlust eines Organs verbunden sind, die einzige kurative Behandlungsoption dar. Um Abstoßungen und damit den Organverlust zu vermeiden ist eine medikamentöse immunsuppressive Therapie nach Transplantation unumgänglich. Trotz enormer Fortschritte im Bereich der medikamentösen Immunsuppression in den letzten Jahrzehnten haben diese Medikamente weiterhin starke Nebenwirkungen. In der Ära der Stammzelltherapie versprechen Mesenchymale Stammzellen einen vielversprechenden Behandlungsansatz. Neben ihren proliferativen Eigenschaften besitzen MSC auch immunmodulatorische Fähigkeiten. Während der vollständige Mechanismus dieser Immunmodulation noch unklar ist, konnte in murinen Überlebensversuchen bereits gezeigt werden, dass MSC das Transplantatüberleben verlängern können. Für diese Arbeit wurde ein f1-Maus-Model gewählt um den Nachweis eines antiproliferativen Effektes von MSC alleine zu erbringen und einen synergistischen Effekt mit verschiedenen medikamentösen Immunsuppressiva zu untersuchen. Hierzu wurden den Versuchstieren der f1-Generation Splenozyten der Parentalgeneration injiziert, welche in den Versuchstieren eine T-Zell-Antwort im Sinne einer Graft-versus-Host-Disease orchestrierten. Durch Fluoreszenzmarkierung wurden diese Effektorzellen nach 48 Stunden identifiziert und einer durchflusszytometrischen Aufarbeitung mit anschließender Proliferationsanalyse zugeführt. Nach Etablierung des Models wurde zunächst der Effekt einer MSC Gabe 24 Stunden vor Effektorzellinjektion auf die T-Zell-Proliferation untersucht. Anschließend wurde die T-Zell-Antwort einer medikamentösen immunsuppressiven Therapie mit Mycofenolat Mofetil, Ciclosporin und Sirolimus durch wiederholte Applikation der Medikamente in unterschiedlicher Dosierung nach Injektion der Effektorzellen unterworfen. Abschließend folgte die Untersuchung eines synergistischen Effektes einer kombinierten Therapie mit MSC und medikamentöser Immunsuppression. Die MSC-Monotherapie zeigte hierbei eine reduzierte Proliferation der Effektorzellen, wobei die Proliferationsanalyse darauf hindeutet, dass sowohl die Aktivierung der T-Zellen, als auch die Proliferationsgeschwindigkeit nach dem Einsatz allogener MSC signifikant verringert werden. In der Monotherapie mit MMF, Ciclosporin und Sirolimus konnte für jedes der Immunsuppressiva eine dosisabhängige Proliferationshemmung nachgewiesen werden. Abschließend konnte für die Kombinationstherapie mit MSC und MMF ein signifikanter synergistischer Effekt auf die Proliferationshemmung der CD4-T-Zellen gezeigt werden, der über das Ausmaß der jeweiligen Monotherapie hinausging, während dies weder für die Kombinationstherapie mit Ciclosporin noch mit Sirolimus gelang

Ileo-right hemi-colonic cervical pull-up on a non-supercharged ileocolic arterial pedicle: A technical and case report

Esophageal reconstruction can be challenging when stomach and colon are not anatomically intact and their use as esophageal substitutes is therefore limited. Innovative individual approaches are then necessary to restore the intestinal passage. We describe a technique in which a short stump of the right hemicolon and 25 cm of ileum on a long, non-supercharged, fully mobilized ileocolic arterial pedicle were used for esophageal reconstruction to the neck. In this case, a 65 year-old male patient had accidentally indigested hydrochloric acid which caused necrosis of his upper digestive tract. An emergency esophagectomy, gastrectomy, duodenectomy, pancreatectomy and splenectomy had been performed in an outside hospital. A cervical esophagostomy and a biliodigestive anastomosis had been created and a jejunal catheter for enteral feeding had been placed. After the patient had recovered, a reconstruction of his food passage via the left and transverse colon failed for technical reasons due to an intraoperative necrotic demarcation of the colon. Our team then faced the situation that only a short stump of the right hemi-colon was left in situ when the patient was referred to our center. After intensified nutritional therapy, we reconstructed this patient's food passage with the right hemicolon-approach described herein. After treatment of a postoperative pneumonia, the patient was discharged from hospital on the 26th postoperative day in a good clinical condition on an oral-only diet. In conclusion, individual approaches for long-segment reconstruction of the esophagus can be technically feasible in experienced hands. They do not always require arterial supercharging or free intestinal transplantation

First-in-Human Case Study: Multipotent Adult Progenitor Cells for Immunomodulation After Liver Transplantation

Mesenchymal stem cells and multipotent adult progenitor cells (MAPCs) have been proposed as novel therapeutics for solid organ transplant recipients with the aim of reducing exposure to pharmacological immunosuppression and its side effects. In the present study, we describe the clinical course of the first patient of the phase I, dose-escalation safety and feasibility study, MiSOT-I (Mesenchymal Stem Cells in Solid Organ Transplantation Phase I). After receiving a living-related liver graft, the patient was given one intraportal injection and one intravenous infusion of third-party MAPC in a low-dose pharmacological immunosuppressive background. Cell administration was found to be technically feasible; importantly, we found no evidence of acute toxicity associated with MAPC infusions

Features of synergism between mesenchymal stem cells and immunosuppressive drugs in a murine heart transplantation model

Background: Mesenchymal stem cells (MSCs) can be used for immunomodulation therapy after solid organ transplantation. Here, we focus on the immunoregulatory potential of combination therapies of MSCs and classic pharmacotherapy to mediate acceptance of solid organ grafts. Methods: To determine which drugs influence the immunosuppressive effect of MSCs, we assessed the interaction of MSCs and common clinical immunosuppresants (MMF, sirolimus [Srl], and ciclosporin A [CiA]) in a parent-into-F1 cell transfer model. In this model, the transfer of parental strain T cells into semi-allogeneic F1 recipients induces a graft-versus-host reaction (GvHR). Re-isolated CFSE-labelled T lymphocytes were analyzed by flow cytometry. These findings were compared to a fully allogeneic heart transplantation model. Results: We found that MSC treatment alone had no significant effect on allograft survival of heterotopic heart grafts. However, MSCs combined with short-term mycophenolate mofetil (MMF) significantly prolonged graft survival. Quantitative analysis of three different MSC - drug combinations in the F1 model revealed, that only the MSC-MMF combination led to a super-additive immunosuppressive effect. We also investigated the effect of MMF and CiA on IFNγ production of stimulated lymphocytes and found that MMF left the expression of IFNγ unaffected, whereas CiA completely abolished the production of IFNγ. Conclusion: Our data show that the type of concurrent immunosuppression strongly influences the immunosuppressive effect of MSC, most likely through differential secretion of IFNγ. A regimen combining MSCs and MMF was most immunosuppressive

Differential effects of heat-inactivated, secretome-deficient MSC and metabolically active MSC in sepsis and allogenic heart transplantation

Mesenchymal stem cells (MSCs) are used in various clinical and preclinical models for immunomodulation. However, it remains unclear how the immunomodulatory effect of MSC is communicated. MSC-induced immunomodulation is known to be mediated through both MSC-secreted cytokines and direct cell-cell interactions. Recently, it has been demonstrated that metabolically inactive, heat-inactivated MSCs (HI-MSCs) have similar anti-inflammatory capacities in LPS-induced sepsis compared with viable MSC. To further investigate the immunomodulatory effects of MSC, we introduced MSC and HI-MSC in two animal models with different immunological causes. In the first model, allogeneic hearts were transplanted from C57BL/6 mice to BALB/c recipients. MSC in combination with mycophenolate mofetil (MMF) significantly improved graft survival compared with MMF alone, whereas the application of HI-MSC had no effect on graft survival. We revealed that control MSC dose-dependently inhibited CD3(+) and CD8(+) T-cell proliferation in vitro, whereas HI-MSC had no effect. In the second model, sepsis was induced in mice via cecal ligation and puncture. HI-MSC treatment significantly improved the overall survival, whereas control MSCs had no effect. in vitro studies demonstrated that HI-MSCs are more effectively phagocytosed by monocytes than control MSCs and induced cell death in particular of activated CD16(+) monocytes, which may explain the immune protective effect of HI-MSC in the sepsis model. The results of our study demonstrate that MSC-mediated immunomodulation in sepsis is dependent on a passive recognition of MSC by monocytes, whereas fully functional MSCs are required for inhibition of T-cell-mediated allograft rejection

Recurrent necrotizing cellulitis, multi-organ autoimmune disease and humoral immunodeficiency due to a novel NFKB1 frameshift mutation

Background: Mutations in NFKB1(nuclear factor of kappa light polypeptide gene enhancer in B-cells 1) are associated with a variety of clinical symptoms, including lymphadenopathy, splenomegaly, hepatomegaly, autoimmune haemolytic anaemia, arthralgia, recurrent respiratory tract infections and post-operative necrotizing cellulitis. Case presentation: We describe a case of a 47-year-old man, who presented with deep necrotizing cellulitis after incision of a submucous abscess by a dentist. Surgical intervention led to a massive progress. Pyoderma gangraenosum (PG) was diagnosed clinically and confirmed histopathologically. High dose corticosteroids and intravenous immunoglobulins (IVIG) improved wound healing dramatically. Until now, immune mediated inflammation events not only affected the skin, but also multiple inner organs, i.e. the heart, lungs and gut. Sequencing of all coding exons of NFKB1 revealed a heterozygous 1bp deletion in exon 23 predicting a frameshift starting at codon Ala891 and resulting in a subsequent stop codon at position 6 in the new reading frame: NM_003998.4: c.2671del; p.(Ala891Glnfs*6) Acute episodes were always successfully treated with corticosteroids, IVIG and concomitant antibiotics. To prevent further exacerbations, the patient receives IVIG once a month, low-dose corticosteroids and methotrexate. Conclusion: This is the first case of a patient with recurrent necrotizing cellulitis and immune mediated multi organ involvement (heart, lungs, intestine) carrying the novel frameshift mutation c.2671del (p. Ala891Glnfs*6) in NFKB1 effectively treated with IVIG, low-dose corticosteroids and methotrexate