W. E. Fibbe

Differential immunomodulatory effects of fetal versus maternal multipotent stromal cells.

Protective mechanisms are likely to be present at the fetomaternal interface because fetus-specific alloreactive T cells present in the decidua do not harm the fetus. We tested the immunosuppressive capacity of maternal and fetal multipotent stromal cells (MSC). Single cell suspensions were made from second-trimester amnion, amniotic fluid, and decidua. Culture-expanded cells were identified as MSC based on phenotype and multilineage potential. Coculture of MSC in a primary mixed lymphocyte culture of unrelated responder-stimulator combinations resulted in a dose-dependent inhibition of proliferation. Fetal MSC demonstrated a significantly higher inhibition compared with maternal MSC. This stronger inhibition by fetal MSC was even more prominent in a secondary mixed lymphocyte reaction (MLR) with primed alloreactive T cells. Analysis of cytokine production revealed that fetal MSC produced significantly more interleukin (IL)-10 and vascular endothelial growth factor than maternal MSC. Cell-cell contact is needed for part of the inhibitory effects of MSC. In addition, soluble factors play a role because blocking experiments with anti-IL-10 revealed that the inhibition of the MLR response by fetal MSC is mainly mediated by IL-10. For maternal MSC, other soluble factors seem to be involved. Fetal MSC derived from the fetomaternal interface have a stronger inhibitory effect on naive and antigen-experienced T cells compared with maternal MSC, which is probably related to their higher IL-10 production.

Cost analysis and quality of life assessment comparing patients undergoing autologous peripheral blood stem cell transplantation or autologous bone marrow transplantation for refractory or relapsed non-Hodgkin's lymphoma or Hodgkin's disease: A prospective randomised trial

The cost-effectiveness of autologous peripheral blood stem cell transplantation (PBSCT) compared with autologous bone marrow transplantation (ABMT) for refractory or relapsed non-Hodgkins lymphoma (NHL) or Morbus Hodgkin (MH) was assessed. Costs were determined from the induction chemotherapy regimen up to 3 months after discharge from hospital following the transplantation. Quality of life was measured by the EuroQol, the Rotterdam Symptom Checklist (RSCL) and the SF-36. Patients were randomised according to a 2:1 ratio to undergo either PBSCT or ABMT. 62 patients underwent PBSCT and 29 ABMT. Costs of the transplantation period were significantly lower in the PBSCT group (15008 Euros) than in the ABMT group (19000 Euros). Significant differences in quality of life were all in favour of PBSCT and emerged using the RSCL, both on 14 days after the transplantation and three months after discharge. We conclude that PBSCT is associated with lower costs and a better quality of life than ABMT for patients with refractory or relapsed NHL or MH.

t(5;12)(q31;p12) A clinical entity with features of both myeloid leukemia and chronic myelomonocytic leukemia

We report two patients with a myeloproliferative disorder (Philadelphia chromosome-negative chronic myeloid leukemia) and t(5;12)(q31;p12). Until now, only three cases of a translocation (5;12)(q31;p12) have been reported. All investigators had problems classifying their patients disease into one of the well-defined entities of either MPD or myelodysplastic disorders. We postulate that this translocation may represent a subgroup of patients with features of both chronic myeloid leukemia and chronic myelomonocytic leukemia (CMMoL).

Comparison of allogeneic T cell-depleted peripheral blood stem cell and bone marrow transplantation: effect of stem cell source on short- and long-term outcome.

We report the results of a retrospective single-center study comparing engraftment, acute and chronic GVHD, relapse and survival in patients with malignant hematological disorders transplanted with allogeneic peripheral blood stem cells (alloPBSCT, n = 40) or bone marrow cells (alloBMT, n = 42). All transplants were T cell depleted by in vitro incubation with the Campath-1 monoclonal antibody. Primary graft failure occurred in none of the patients receiving an alloPBSCT compared with 3/42 of the recipients of an alloBMT. In addition, two patients in the alloBMT group showed no platelet engraftment. Recipients of PBSC had a more rapid recovery of neutrophils (median 14 days) compared to BM transplant recipients (median 32 days). Platelet recovery was also accelerated in PBSC recipients compared to BM recipients (11 vs 38 days). There was an increase in the incidence of grade II acute GVHD and chronic GVHD in patients after alloPBSCT (18% and 23%, respectively) compared to patients receiving alloBMT (5% and 8%, respectively). The 2-year cumulative incidence of relapse was similar in both groups (47%). At 6 months after transplantation, transplant-related mortality (TRM) was lower in PBSCT recipients than in BMT recipients. However, at a follow-up of 3 years TRM was similar in both groups. The disease-free survival rate at 3 years after transplantation did not differ between the groups (42% for PBSCT and 41% for BMT recipients). Our results indicate that T cell-depleted alloPBSCT compared to alloBMT is associated with a more rapid hematopoietic reconstitution and a decreased TRM at 6 months follow-up after transplantation. However, at a follow-up of 3 years, no sustained survival benefits were observed. Bone Marrow Transplantation (2001) 27, 1053–1058.

Safety of allogeneic bone marrow derived mesenchymal stromal cell therapy in renal transplant recipients: the neptune study

BackgroundMesenchymal stromal cells (MSC) may serve as an attractive therapy in renal transplantation due to their immunosuppressive and reparative properties. While most studies have used autologous MSCs, allogeneic MSCs offer the advantage of immediate availability for clinical use. This is of major importance for indications where instant treatment is needed, for example allograft rejection or calcineurin inhibitor toxicity. Clinical studies using allogeneic MSCs are limited in number. Although these studies showed no adverse reactions, allogeneic MSCs could possibly elicit an anti-donor immune response, which may increase the incidence of rejection and impact the allograft survival in the long term. These safety issues should be addressed before further studies are planned with allogeneic MSCs in the solid organ transplant setting.Methods/design10 renal allograft recipients, 18–75xa0years old, will be included in this clinical phase Ib, open label, single center study. Patients will receive two doses of 1.5xa0×xa0106 per/kg body weight allogeneic bone marrow derived MSCs intravenously, at 25 and 26xa0weeks after transplantation, when immune suppression levels are reduced. The primary end point of this study is safety by assessing biopsy proven acute rejection (BPAR)/graft loss after MSC treatment. Secondary end points, all measured before and after MSC infusions, include: comparison of fibrosis in renal biopsy by quantitative Sirius Red scoring; de novo HLA antibody development and extensive immune monitoring; renal function measured by cGFR and iohexol clearance; CMV and BK infection and other opportunistic infections.DiscussionThis study will provide information on the safety of allogeneic MSC infusion and its effect on the incidence of BPAR/graft loss.Trial registration: NCT02387151

Autologous bone marrow derived mesenchymal stromal cell therapy in combination with everolimus to preserve renal structure and function in renal transplant recipients

BackgroundKidney transplantation has improved survival and quality of life for patients with end-stage renal disease. Despite excellent short-term results due to better and more potent immunosuppressive drugs, long-term survival of transplanted kidneys has not improved accordingly in the last decades. Consequently there is a strong interest in immunosuppressive regimens that maintain efficacy for the prevention of rejection, whilst preserving renal structure and function. In this respect the infusion of mesenchymal stromal cells (MSCs) may be an interesting immune suppressive strategy. MSCs have immune suppressive properties and actively contribute to tissue repair. In experimental animal studies the combination of mammalian target of rapamycin (mTOR) inhibitor and MSCs was shown to attenuate allo immune responses and to promote allograft tolerance. The current study will test the hypothesis that MSC treatment, in combination with the mTOR inhibitor everolimus, facilitates tacrolimus withdrawal, reduces fibrosis and decreases the incidence of opportunistic infections compared to standard tacrolimus dose.Methods/design70 renal allograft recipients, 18–75 years old, will be included in this Phase II, open label, randomized, non-blinded, prospective, single centre clinical study. Patients in the MSC treated group will receive two doses of autologous bone marrow derived MSCs IV (target 1,5x106, Range 1-2x106 million MSCs per/kg body weight), 7xa0days apart, 6 and 7xa0weeks transplantation in combination with everolimus and prednisolone. At the time of the second MSC infusion tacrolimus will be reduced to 50% and completely withdrawn 1xa0week later. Patients in the control group will receive everolimus, prednisolone and standard dose tacrolimus. The primary end point is to compare fibrosis by quantitative Sirius Red scoring of MSC treated and untreated groups at 6xa0months compared to 4xa0weeks post-transplant. Secondary end points include: composite end point efficacy failure (Biopsy Proven Acute Rejection, graft loss or death); renal function and proteinuria; opportunistic infections; immune monitoring and “subclinical” cardiovascular disease groups by assessing echocardiography in the different treatment groups.DiscussionThis study will provide information whether MSCs in combination with everolimus can be used for tacrolimus withdrawal, and whether this strategy leads to preservation of renal structure and function in renal recipients.Trial registrationhttp://www.clinicaltrials.gov/NCT02057965.

A phase I study for intravenous autologous mesenchymal stromal cell administration to patients with severe emphysema

BACKGROUNDnMesenchymal stromal cells (MSCs) may reduce inflammation and promote tissue repair in pulmonary emphysema.nnnAIMnTo study the safety and feasibility of bone marrow-derived autologous (BM-) MSC intravenous administration to patients with severe emphysema.nnnDESIGNnA phase I, prospective open-label study registered at ClinicalTrials.gov as NCT01306513 Eligible patients had lung volume reduction surgery (LVRS) on two separate occasions. During the first LVRS bone marrow was collected, from which MSCs were isolated and expanded ex vivo After 8 weeks, patients received two autologous MSC infusions 1 week apart, followed by the second LVRS procedure at 3 weeks after the second BM-MSC infusion.nnnMETHODSnUp to 3 weeks after the last MSC infusion adverse events were recorded. Using immunohistochemistry and qPCR for analysis of cell and proliferation markers, emphysematous lung tissue obtained during the first surgery was compared with lung tissue obtained after the second surgical session to assess BM-MSC effects.nnnRESULTSnFrom 10 included patients three were excluded: two did not receive MSCs due to insufficient MSC culture expansion, and one had no second surgery. No adverse events related to MSC infusions occurred and lung tissue showed no fibrotic responses. After LVRS and MSC infusions alveolar septa showed a 3-fold increased expression of the endothelial marker CD31 (P u2009= u20090.016).nnnCONCLUSIONSnAutologous MSC treatment in severe emphysema is feasible and safe. The increase in CD31 expression after LVRS and MSC treatment suggests responsiveness of microvascular endothelial cells in the most severely affected parts of the lung.

Differentiation of follicular lymphoma cells after autologous bone marrow transplantation and haematopoietic growth factor treatment

A patient with follicular lymphoma developed a striking but transient plasmacytosis in blood and bone marrow with paraproteinaemia after treatment by autologous bone marrow transplantation and interleukin-3 (IL-3). By immunophenotyping, cytogenetics and Southern blotting, we proved that the plasma cells were clonally related to the original lymphoma cells. This event was preceded by fever accompanied by high IL-6 concentrations. The patient recovered spontaneously and had a long-lasting remission. We speculate that the bone marrow-derived malignant B cells were stimulated by IL-3 and IL-6 into terminally differentiated plasma cells.

Factors influencing release of granulocyte‐macrophage colony‐stimulating activity from human mononuclear phagocytes*

Mononuclear phagocytes play an important role in the regulation of hematopoiesis, not only by producing regulatory monokines such as prostaglandins, tumor necrosis factor and interleukin‐1 (IL‐1), but also by the production of colony‐stimulating activity (CSA). Previously, we have demonstrated that granulocyte‐macrophage CSA (GM‐CSA) production by mononuclear phagocytes can be induced by IL‐1. In the present study, the influence of culture conditions on the production of GM‐CSA was studied. It was found that both human sera and fetal bovine sera contain constituents — at present undefined — that induce GM‐CSA production. These factors are distinct from IL‐1 and lipopolysaccharide. In selected experiments, no GM‐CSA‐inducing effect of serum was found, suggesting that the effect may be donor‐related. GM‐CSA release in the presence of serum could be reduced by 40% after incubation of mononuclear phagocytes at low cell concentrations in methylcellulose, indicating that intimate cell‐cell contact is an additional factor that enhances GM‐CSA release.

Impaired effector memory T-cell regulation facilitates graft versus host disease in CCR7-deficient bone marrow transplant chimeras.

Background. The development of graft versus host disease (GvHD) is one of the major challenges of bone marrow transplantations (BMTs). Although clinical symptoms of GvHD share many features with auto immune diseases, the underlying mechanisms remain unclear. Here, we examined the effects of hematopoietic CC-chemokine receptor (CCR)7 deficiency on the development of GvHD. Methods. Lethally irradiated C57BL/6 mice were transplanted with bone marrow cells derived from wild-type or CCR7−/− C57BL/6 donor mice. Results. Unlike littermate controls, CCR7−/− chimeras develop overt GvHD-like symptoms within 6 weeks after transplantation. Circulating CD4+ and CD8+ T-cell populations of CCR7−/− chimeras were enriched in effector memory T cells. CCR7− CD62L+ regulatory T-cell expansion, which typically occurs after BMT was markedly delayed in CCR7−/− chimeras. Furthermore, GvHD-like reactions did not occur after cotransplantation of wild-type and CCR7−/− bone marrow, showing that CCR7 is critically required for tolerance induction and prevention of GvHD. Conclusions. We are the first to demonstrate that lack of CCR7 results in delayed regulatory T-cell expansion. This results in insufficient control of effector memory T-cell expansion, which eventually leads to severe tissue damage. Conceivably, therapies aimed at boosting CD4+ CD62L+ regulatory T-cell expansion after BMT could help to control GvHD.