Remission and relapse of Crohn's disease following autologous haematopoietic stem cell transplantation for non-Hodgkin's lymphoma

The Role of Inflammation in Crohn's Disease Recurrence after Surgical Treatment

Introduction

Postoperative recurrence after surgery for Crohn's disease (CD) is virtually inevitable, and its mechanism is poorly known.

Aim

To review the numerous factors involved in CD postoperative recurrence (POR) pathogenesis, focusing on single immune system components as well as the immune system as a whole and highlighting the clinical significance in terms of preventive strategies and future perspectives.

Methods

A systematic literature search on CD POR, followed by a review of the main findings.

Results

The immune system plays a pivotal role in CD POR, with many different factors involved. Memory T-lymphocytes retained in mesenteric lymph nodes seem to represent the main driving force. New pathophysiology-based preventive strategies in the medical and surgical fields may help reduce POR rates. In particular, surgical strategies have already been developed and are currently under investigation.

Conclusions

POR is a complex phenomenon, whose driving mechanisms are gradually being unraveled. New preventive strategies addressing these mechanisms seem promising.

Umbilical cord blood mononuclear cell therapy induces clinical remission of steroid-dependent or -resistant ulcerative colitis patients

To compare the efficacy and safety of umbilical cord blood mononuclear cells (CBMNC) and azathioprine (AZA) in the treatment of patients with steroid-dependent or -resistant ulcerative colitis. One hundred and six patients diagnosed with steroid-dependent or -resistant ulcerative colitis were studied retrospectively, including 36 patients treated with CBMNC and 70 treated with AZA. To reduce confounding bias due to retrospective nature of this study, the propensity score matching system was applied to equipoise the pretreatment data of two groups. After matching, 35 matched pairs (1:1) were created. The ratios of clinical remission, clinical response and endoscopic mucosal healing, Mayo score, and major complications were compared between two groups at weeks 8, 16, and 36 after treatment. The results demonstrated that the ratios of clinical remission (80% vs. 57%, P < 0.05) and mucosal healing (74% vs. 51%, P < 0.05) were significantly higher in CBMNC-treated patients compared with those in AZA-treated patients at week 8. The erythrocyte sedimentation rate was significantly decreased in CBMNC group compared with that in AZA-treated group (14.5 ± 3.9 mm/h vs. 18.0 ± 5.7 mm/h, P < 0.01) at week 8. In AZA group, 2 patients had neutropenia and 3 patients had elevated alanine aminotransferase levels, whereas no obvious side-effects were observed in CBMNC-treated group. Our results reveal that CBMNC therapy appears to be an effective and safe strategy for patients with steroid-dependent or -resistant ulcerative colitis. Further prospective studies are needed to define the potential roles and mechanisms of CBMNC in the treatment of refractory ulcerative colitis.

Autologous hematopoietic stem cells for refractory Crohn's disease

INTRODUCTION

Autologous hematopoietic stem cells are gaining ground as an effective and safe treatment for treating severe refractory Crohn's disease (CD). Autologous hematopoietic stem cell therapy (AHSCT) induces resetting of the immune system by de novo regeneration of T-cell repertoire and repopulation of epithelial cells by bone-marrow derived cells to help patients achieve clinical and endoscopic remission. Areas covered: Herein, the authors discuss the use of AHSCT in treating patients with CD. Improvements in disease activity have been seen in patients with severe autoimmune disease and patients with severe CD who underwent AHSCT for a concomitant malignant hematological disease. Clinical and endoscopic remission has been achieved in patients treated with AHSCT for CD. The only randomized trial published to date, the ASTIC Trial, did not support further use of AHSCT to treat CD. Yet, critics of this trial have deemed AHSCT as a promising treatment for severe refractory CD. Expert opinion: Even with the promising evidence presented for HSCT for refractory CD, protocols need to be refined through the collaboration of GI and hemato-oncology professionals. The goal is to incorporate safe AHSCT and restore tolerance by delivering an effective immune 'cease fire' as a treatment option for severe refractory CD.

Stem cell therapy for inflammatory bowel disease

Inflammatory bowel disease (IBD) could be curable by "immune rest" and correction of the genetic predisposition inherent in allogeneic hematopoietic stem cell transplantation. However, balancing risks against benefits remains challenging. The application of mesenchymal stem cells (MSCs) serving as a site-regulated "drugstore" is a recent concept, which suggests the possibility of an alternative treatment for many intractable diseases such as IBD. Depending on the required function of MSC, such as a cell provider, immune moderator, and/or trophic resource, MSC therapy should be optimized to maximize its therapeutic benefit. Therapeutic effects do not always require full engraftment of MSCs. Therefore, optimization of pleiotropic gut trophic factors produced by MSCs, which favoring not only regulating immune responses but also promoting tissue repair, must directly enhance new drug discoveries for treatment of IBD. Stem cell biology holds great promise for a new era of cell-based therapy, sparking considerable interest among scientists, clinicians, and patients. However, the translational arm of stem cell science remains in a relatively primitive state. Although several clinical studies using MSCs have been initiated, early results suggest several inherent problems. In each study, optimization of MSC therapy appears to be the most urgent problem, and can be resolved only by scientifically unveiling the mechanisms of therapeutic action. In the present review, the authors outline how such information would facilitate the critical steps in the paradigm shift from basic research on stem cell biology to clinical practice of regenerative medicine for conquering IBD in the near future.

Hematopoietic stem cell transplantation for non-malignant gastrointestinal diseases

Both, autologous and allogeneic hematopoietic stem cell transplantation (HSCT) can be used to cure or ameliorate a variety of malignant and non-malignant diseases. The rationale behind this strategy is based on the concept of immunoablation using high-dose chemotherapy, with subsequent regeneration of naive T-lymphocytes derived from reinfused hematopoietic progenitor cells. In addition, the use of HSCT allows for the administration of high-dose chemotherapy (whether or not combined with immunomodulating agents such as antithymocyte globulin) resulting in a prompt remission in therapy-refractory patients. This review gives an update of the major areas of successful uses of HSCT in non-malignant gastrointestinal disorders. A Medline search has been conducted and all relevant published data were analyzed. HSCT has been proved successful in treating refractory Crohn’s disease (CD). Patients with refractory celiac disease type II and a high risk of developing enteropathy associated T-cell lymphoma have shown promising improvement. Data concerning HSCT and mesenchymal SCT in end-stage chronic liver diseases are encouraging. In refractory autoimmune gastrointestinal diseases high-dose chemotherapy followed by HSCT seems feasible and safe and might result in long-term improvement of disease activity. Mesenchymal SCT for a selected group of CD is promising and may represent a significant therapeutic alternative in treating fistulas in CD.

Stem cells as treatment in inflammatory bowel disease

BACKGROUND

The Autologous Stem Cell Transplantation International Crohn's Disease (ASTIC) trial is a randomised controlled evaluation of the proposition that immunoablation and haemopoietic stem cell transplantation improves the course of Crohn's disease. Recruitment of all 48 patients in the trial will be completed in early 2012 and the results to date are descriptively presented here.

METHODS

Patients with an impaired quality of life due to active Crohn's disease, despite the administration of at least 3 immunosuppressive agents, all received mobilisation treatment (cyclophosphamide 4 g/m(2) over 2 days followed by recombinant human granulocyte colony stimulating factor (filgrastim) 10 µg/kg daily before randomisation to immediate (after 1 month) or delayed (after 1 year) immunoablation and stem cell transplantation. The conditioning regime was cyclophosphamide 50 mg/kg/day for 4 days, anti-thymocyte globulin 2.5 mg/kg/day and methylprednisolone 1 mg/kg on days 3-5. The bone marrow was reconstituted by the infusion of an unselected graft of 3-8 × 10(6)/kg CD34-positive stem cells. Results were compared 1 year after mobilisation alone or after transplantation.

RESULTS

Twelve months after stem cell transplantation (early or delayed) the Crohn's Disease Activity Index (CDAI) fell from 324 (median, interquartile range 229-411) to 161 (85-257, n = 17) compared to 351 (287-443) to 272 (214-331) following mobilisation alone (n = 11). Six patients had a normal CDAI after transplantation versus 1 after mobilisation. C-reactive protein fell from 16.6 (6.7-32.0) to 6.5 (3.5-12.5) mg/l versus 14 (8.0-27.0) to 9.0 (2.0-23.4) mg/l following mobilisation alone. The Crohn's Disease Endoscopic Index of Severity (CDEIS) (aggregate for upper and lower endoscopy) fell from 18 (10-25) to 5 (1-11) following transplantation versus 14 (12-16) to 9 (4-22) following mobilisation. Three patients achieved the goal of a normal CDAI, no drug therapy and normal upper and lower endoscopy 1 year after transplantation, but so did 1 patient following mobilisation alone. Serious adverse events were common (n = 100 to date) with 42 infective episodes requiring or prolonging hospitalisation, following both mobilisation and conditioning and transplantation. There were 7 episodes of viral (re)activation. Temporary flare of Crohn's disease activity or a need for surgery occurred in 8 patients.

CONCLUSIONS

Immunoablation and haemopoietic stem cell transplantation appear to be an effective treatment for some patients with Crohn's disease, although full results will be required for a firm conclusion. The risks are significant, making it potentially suitable for only a limited number of patients. Data from the whole trial will be needed to judge whether mobilisation alone has any benefits.

Loss of interleukin-10 signaling and infantile inflammatory bowel disease: implications for diagnosis and therapy

BACKGROUND & AIMS

Homozygous loss of function mutations in interleukin-10 (IL10) and interleukin-10 receptors (IL10R) cause severe infantile (very early onset) inflammatory bowel disease (IBD). Allogeneic hematopoietic stem cell transplantation (HSCT) was reported to induce sustained remission in 1 patient with IL-10R deficiency. We investigated heterogeneity among patients with very early onset IBD, its mechanisms, and the use of allogeneic HSCT to treat this disorder.

METHODS

We analyzed 66 patients with early onset IBD (younger than 5 years of age) for mutations in the genes encoding IL-10, IL-10R1, and IL-10R2. IL-10R deficiency was confirmed by functional assays on patients' peripheral blood mononuclear cells (immunoblot and enzyme-linked immunosorbent assay analyses). We assessed the therapeutic effects of standardized allogeneic HSCT.

RESULTS

Using a candidate gene sequencing approach, we identified 16 patients with IL-10 or IL-10R deficiency: 3 patients had mutations in IL-10, 5 had mutations in IL-10R1, and 8 had mutations in IL-10R2. Refractory colitis became manifest in all patients within the first 3 months of life and was associated with perianal disease (16 of 16 patients). Extraintestinal symptoms included folliculitis (11 of 16) and arthritis (4 of 16). Allogeneic HSCT was performed in 5 patients and induced sustained clinical remission with a median follow-up time of 2 years. In vitro experiments confirmed reconstitution of IL-10R-mediated signaling in all patients who received the transplant.

CONCLUSIONS

We identified loss of function mutations in IL-10 and IL-10R in patients with very early onset IBD. These findings indicate that infantile IBD patients with perianal disease should be screened for IL-10 and IL-10R deficiency and that allogeneic HSCT can induce remission in those with IL-10R deficiency.

Review article: stem cell therapies for inflammatory bowel disease - efficacy and safety

BACKGROUND

Drugs available for the treatment of inflammatory bowel disease fail to induce and maintain remission in a significant number of patients.

AIM

To assess the value of stem cell therapies for treatment of inflammatory bowel disease based on published studies.

METHODS

Publications were identified through a MEDLINE search using the Medical Subject Heading terms: inflammatory bowel diseases, or Crohn's disease, or ulcerative colitis, and stem cell, or stromal cell or transplant.

RESULTS

Haematopoietic stem cell therapy as a primary treatment for inflammatory bowel disease was originally supported by animal experiments, and by remissions in patients undergoing transplant for haematological disorders. Later, transplantation specifically performed for patients with refractory Crohn's disease showed long-lasting clinical remission and healing of inflammatory intestinal lesions. Use of autologous nonmyeloablative regimens and concentration of the procedures in centres with large experience are key in reducing treatment-related mortality. Initial trials of mesenchymal stem cell therapy with local injection in Crohn's perianal fistulas had positive results.

CONCLUSIONS

Autologous haematopoietic stem cell transplant changes the natural course of Crohn's disease, and may be a therapeutic option in patients with refractory disease if surgery is not feasible due to disease location or extension.

Stem cell therapeutics: potential in the treatment of inflammatory bowel disease

Stem cell therapies may be valuable in treatment of inflammatory bowel disease (IBD). Here we focus on two very different types of stem cells - hematopoietic stem cells and mesenchymal stem cells. Myeloablation and hematopoietic stem cell transplantation alter host immune response by reconstituting the recipient's blood cell lines with donor cells. Autologous hematopoietic reconstitution may "reboot" mucosal immunity to a normal baseline state, but does not alter any underlying genetic predisposition to IBD. In contrast, allogeneic hematopoietic transplantation reconstitutes all blood lineages from a tissue-matched donor who presumably does not have a genetic predisposition to IBD. Compared with autologous hematopoietic transplantation, allogeneic hematopoietic transplantation carries a much greater risk of complications, including graft-versus-host disease. Mesenchymal stem cells can give rise to cartilage, bone and fat in vitro, but do not reconstitute hematopoiesis after transplantation. Systemically infused mesenchymal stem cells appear to favorably downregulate host immune responses through poorly understood mechanisms. In addition, mesenchymal stem cells may be applied topically to help close fistulas associated with Crohn's disease. For all of these stem cell therapy applications for IBD, only cases and small series have been reported. Larger clinical trials are planned or ongoing.

Inflammatory bowel disease following solid organ transplantation

Inflammatory bowel disease (IBD) is a T cell driven inflammatory condition of the gut. Following solid organ transplantation (SOT), de novo IBD has been reported despite anti-T cell therapy for the prevention of organ rejection. This paradox is illustrated with a case report, highlighting the difficult diagnostic criteria, the potential role of Damage or Pathogen Associated Molecular Pattern Molecules [DAMPs and PAMPs] that drives aspects of ongoing inflammation within the transplanted organ as well as the intestine, and the therapeutic strategies applied. Recurrent IBD is more common than de novo IBD following transplantation, with cumulative risks ten years after orthotopic liver transplantation of 70% and 30%, respectively. Furthermore, the annual incidence of de novo IBD following solid organ transplantation has been estimated to be 206 cases/100,000 or ten times the expected incidence of IBD in the general population (approximately 20 cases/100,000). The association of IBD with other autoimmune conditions such as primary sclerosing cholangitis and autoimmune hepatitis, both common indications for liver transplantation, may play a contributory role, particularly in view of the observation that IBD is more common following liver transplant than other solid organ transplants. Recurrent IBD following transplant appears to run a more aggressive course than de novo IBD, with a higher proportion requiring colectomy for medically refractory disease. Risk factors that have been associated with development of post-transplant IBD include acute CMV infection and the use of tacrolimus.