Hematopoietic stem cell transplantation for severe Crohn's disease

Hematopoietic Stem Cell Transplantation in Refractory Crohn's Disease: Should It Be Considered?

Hematopoietic stem cell transplantation (HSCT) is widely used in benign and malignant hematological diseases. During the last decade, HSCT, mainly autologous, also gained increasing attention in the treatment of refractory autoimmune diseases. Crohn's disease (CD) is an inflammatory bowel disease leading to transmural inflammation potentially affecting all parts of the luminal gastrointestinal tract. Despite improving therapeutic options, including various biologics, some patients are refractory to all lines of available conservative therapy, leading to increased morbidity and reduced quality of life. Apart from surgery, HSCT might be a reasonable treatment alternative for refractory CD patients. This review aims to describe the current role of HSCT in CD and discusses the procedure, the correct patient selection, the clinical efficacy from initial remission to following relapse rates, and complications of this treatment.

Stem cell transplantation for induction of remission in medically refractory Crohn's disease

BACKGROUND

Crohn's disease (CD) is an inflammatory bowel disease that causes inflammation and stricture, of any part of the mucosa and the gut wall. It forms skip lesions, sparing the areas in between the affected parts of the gastrointestinal tract. Crohn's disease could have one of three complications; fistula, intestinal obstruction due to stricture, or gastrointestinal inflammation presenting as severe diarrhoea. Stem cell therapy (SCT) is an innovative treatment that has been recently used in CD. The exact role of SCT in CD is still unclear. Stem cells modify the immunity of the patients or act as a "reset tool" for the immune system as in the case of systemically-injected stem cells, or regenerate the affected area of necrotic and inflammatory tissue as in the case of local injection into the lesion. Stem cells are a wide variety of cells including pluripotent stem cells or differentiated stem cells. The hazards range from rejection to symptomatic manifestations as fever or increase infection.  OBJECTIVES: The objective of this Cochrane systematic review is to assess the effects of stem cell transplantation compared to standard of care alone or with placebo on efficacy and safety outcomes in patients with refractory CD.

SEARCH METHODS

We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and clinical trial registries (Clinicaltrials.gov, World Health Organization-International Clinical Trials Registry Platform WHO ICTRP) from inception to 19 March 2021, without any language, publication year, or publication status restrictions. In addition, we searched references of included studies and review articles for further references. An update of the published studies was done during the writing of the review.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) that assessed the effectiveness and safety of SCT in refractory CD versus standard care alone (control) or with placebo.

DATA COLLECTION AND ANALYSIS

Two review authors (SEN and SFA) independently screened the studies retrieved from the search results for inclusion, extracted data and assessed the risk of bias. Any disagreement was resolved through a consensus between the authors. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We conducted our search on 19 March 2021 and identified 639 records. We added two records by a manual search of the published reviews on the topic to a total of 641 records. The Covidence program removed 125 duplicates making a total of 516 reports. Two review authors (SEN and SFA) screened titles and abstracts and excluded 451 records with the remaining 65 for full-text records screened independently by the two authors; only 18 studies were considered for inclusion.  We included seven RCTs with a total of 442 participants for the meta-analysis. The intervention group included 234 patients, and the control group included 208 patients. Nine trials are ongoing and, two abstracts are awaiting classification. All patients in the control and intervention groups received the standard therapy for CD. Only three studies used blinding methods for the control group in the form of a placebo, with one study of the three stated that the blinding method was inefficient. The patients and personnel were aware of the intervention in the rest of the four studies as they were open-label trials. However, the effect of unblinding was balanced by the low risk of detection bias in five of the included studies. The evidence is uncertain about the effect of SCT on achieving clinical remission as compared to control/placebo (risk ratio (RR) 1.88, 95% Confidence Interval (CI) 0.80 to 4.41; 3 studies; low-certainty evidence). The evidence is very uncertain about the effect of SCT on achieving Crohn's Disease Activity Index (CDAI) <150 at 24 weeks compared to control (RR1.02 95% CI 0.67 to 1.56; 4 studies; very-low certainty evidence). SCT is likely to achieve fistula closure as compared to the control/placebo both in the short term (RR 1.48, 95% CI 1.12 to 1.96); low-certainty evidence) and in the long term (RR 1.42, 95% CI 1.09 to 1.87; 4 studies; low-certainty evidence) follow-up. The evidence is very uncertain about the effect of SCT to cause no difference in the number of total adverse events as compared to the control/placebo (RR 0.99, 95% CI [0.88 to  1.13); 4 studies; very-low-certainty evidence). However, SCT is likely to increase the number of serious adverse events as compared to the control/placebo (RR 1.22, 95% CI 0.88 to 1.67; 7 studies; low-certainty evidence). The evidence is very uncertain about the effect of SCT to decrease the withdrawal due to adverse events as compared to the control/placebo (RR 0.78, 95% CI 0.32 to 1.89; 3 studies; very-low certainty evidence). Funding by pharmaceutical companies was found in three studies, with one including more than 50% of our studied population.

AUTHORS' CONCLUSIONS

SCT shows an uncertain effect on clinical remission with low certainty of evidence. SCT shows an uncertain effect on CDAI score to reach <150 after 24 weeks of treatment, with very low certainty evidence. SCT shows beneficial effects on fistula-closure during short and long-term follow-up with low-certainty evidence in both outcomes. There was no change in the total number of adverse events with SCT as compared to control, with very low certainty evidence. While there was a moderate effect on increasing the number of serious adverse events in the SCT group, as compared to the control with low-certainty evidence. Withdrawal due to adverse events was slightly higher in the control group with very low certainty evidence. All the participants were refractory to standard medical treatment, but the number of participants was small, this may limit the generalizability of the results. Further research is needed for validation. More objective outcomes are needed in the assessment of stem cell effectiveness in the treatment of Crohn's disease, especially the intestinal CD subtype; with standardization of the dose, methods of stem cell preparation, route of administration, and inclusion criteria to the studies to achieve clear results.

A review of hematopoietic stem cell transplantation for autoimmune diseases: multiple sclerosis, systemic sclerosis and Crohn's disease. Position paper of the Brazilian Society of Bone Marrow Transplantation

Autoimmune diseases are an important field for the development of bone marrow transplantation, or hematopoietic stem cell transplantation. In Europe alone, almost 3000 procedures have been registered so far. The Brazilian Society for Bone Marrow Transplantation (Sociedade Brasileira de Transplantes de Medula Óssea) organized consensus meetings for the Autoimmune Diseases Group, to review the available literature on hematopoietic stem cell transplantation for autoimmune diseases, aiming to gather data that support the procedure for these patients. Three autoimmune diseases for which there are evidence-based indications for hematopoietic stem cell transplantation are multiple sclerosis, systemic sclerosis and Crohn's disease. The professional stem cell transplant societies in America, Europe and Brazil (Sociedade Brasileira de Transplantes de Medula Óssea) currently consider hematopoietic stem cell transplantation as a therapeutic modality for these three autoimmune diseases. This article reviews the evidence available.

The recruitment of extra-intestinal cells to the injured mucosa promotes healing in radiation enteritis and chemical colitis in a mouse parabiosis model

Mucosal healing occurs through migration and proliferation of cells within injured epithelium, yet these processes may be inadequate for mucosal healing after significant injury where the mucosa is denuded. We hypothesize that extra-intestinal cells can contribute to mucosal healing after injury to the small and large intestine. We generated parabiotic pairs between wild-type and tdTomato mice, which were then subjected to radiation-induced enteritis and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. We now show that as compared with singleton mice, mice with a parabiotic partner were protected against intestinal damage as revealed by significantly reduced weight loss, reduced expression of pro-inflammatory cytokines, reduced enterocyte apoptosis, and improved crypt proliferation. Donor cells expressed CD45-, Sca-1+, c-kit+, and CXCR4+ and accumulated around the injured crypts but did not transdifferentiate into epithelia, suggesting that extra-intestinal cells play a paracrine role in the healing response, while parabiotic pairings with Rag1-/- mice showed improved healing, indicating that adaptive immune cells were dispensable for mucosal healing. Strikingly, ablation of the bone marrow of the donor parabionts removed the protective effects. These findings reveal that the recruitment of extra-intestinal, bone marrow-derived cells into the injured intestinal mucosa can promote mucosal healing, suggesting novel therapeutic approaches for severe intestinal disease.

Autologous Haematopoietic Stem Cell Transplantation for Refractory Crohn's Disease: Efficacy in a Single-Centre Cohort

BACKGROUND

Haematopoietic stem cell transplantation [HSCT] is considered a therapeutic option for patients with severe Crohn's disease [CD] unresponsive to currently available therapies.

METHODS

Autologous HSCT was considered for CD patients with active disease, unresponsive or intolerant to approved medications and unsuitable for surgery. After HSCT, patients were closely followed up every 6 weeks during the first 2 years and every 6 months thereafter up to 5 years. Colonoscopy and/or magnetic resonance imaging were performed at Months 6, 12, 24, and 48 after HSCT.

RESULTS

From December 1, 2007 to December 31, 2015, 37 CD patients were assessed for HSCT. Of these, 35 patients [13 within the ASTIC trial] underwent mobilisation. Six patients did not complete the transplant for various reasons and 29 patients were finally transplanted. Patients were followed up during a median of 12 months [6-60]. At 6 months, 70% of patients achieved drug-free clinical remission (Crohn's Disease Index of Severity [CDAI] < 150). The proportion of patients in drug-free remission (CDAI < 150, Simple Endoscopic activity Score [SES]-CD < 7] was 61% at 1 year, 52% at 2 years, 47% at 3 years, 39% at 4 years, and 15% at 5 years. Patients who relapsed were re-treated and 80% regained clinical remission. Six out of the 29 [21%] required surgery. One patient died due to systemic cytomegalovirus infection 2 months after transplant.

CONCLUSIONS

HSCT is a salvage therapy for patients with extensive and refractory CD. Although relapse occurs in a majority of patients within 5 years after transplant, drug responsiveness is regained and clinical remission achieved in 80% of cases.

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.

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.

Therapy with stem cells in inflammatory bowel disease

Inflammatory bowel disease (IBD) affects a part of the young population and has a strong impact upon quality of life. The underlying etiology is not known, and the existing treatments are not curative. Furthermore, a significant percentage of patients are refractory to therapy. In recent years there have been great advances in our knowledge of stem cells and their therapeutic applications. In this context, autologous hematopoietic stem cell transplantation (HSCT) has been used in application to severe refractory Crohn’s disease (CD), with encouraging results. Allogenic HSCT would correct the genetic defects of the immune system, but is currently not accepted for the treatment of IBD because of its considerable risks. Mesenchymal stem cells (MSCs) have immune regulatory and regenerative properties, and low immunogenicity (both autologous and allogenic MSCs). Based on these properties, MSCs have been used via the systemic route in IBD with promising results, though it is still too soon to draw firm conclusions. Their local administration in perianal CD is the field where most progress has been made in recent years, with encouraging results. The next few years will be decisive for defining the role of such therapy in the management of IBD.

Current and future immunomodulation strategies to restore tolerance in autoimmune diseases

Autoimmune diseases reflect a breakdown in self-tolerance that results from defects in thymic deletion of potentially autoreactive T cells (central tolerance) and in T-cell intrinsic and extrinsic mechanisms that normally control potentially autoreactive T cells in the periphery (peripheral tolerance). The mechanisms leading to autoimmune diseases are multifactorial and depend on a complex combination of genetic, epigenetic, molecular, and cellular elements that result in pathogenic inflammatory responses in peripheral tissues driven by self-antigen-specific T cells. In this article, we describe the different checkpoints of tolerance that are defective in autoimmune diseases as well as specific events in the autoimmune response which represent therapeutic opportunities to restore long-term tolerance in autoimmune diseases. We present evidence for the role of different pathways in animal models and the therapeutic strategies targeting these pathways in clinical trials in autoimmune diseases.

[Clinical trials with stem cells in digestive diseases and future perspectives]

Many techniques for isolation, expansion and handling of stem cells are being developed rapidly, and preclinical evidence has shown the possibility to use this technology for refractory diseases in the near future. Among refractory digestive diseases, Crohn's disease and liver cirrhosis may be two main diseases where stem cell therapy can be applied for anti-inflammation and regeneration of tissue. Currently, with respect to these two diseases, clinical trials using hematopoietic stem cells and mesenchymal stem cells from bone marrow or adipose tissue have shown some evidence of clinical benefits to immune modulation, suppression of inflammation and regeneration of functional cells. However, for the development of practical stem cell therapy, we need more data on underlying mechanisms, effective subpopulation of stem cells and its sources, and effective parameters for monitoring and estimation. With technical advances, the research on embryonic and induced pluripotent stem cells will also contribute to the new therapeutic strategies for digestive regenerative medicine. In the future, a variety of stem cell therapies may be therapeutic options for refractory digestive diseases, but many technical challenges remain to be solved. (Korean J Gastroenterol 2011;58:139-143).

Autologous hematopoietic stem cell transplantation in autoimmune diseases

The term 'autoimmune diseases' encompasses a spectrum of diseases whose clinical manifestations and, possibly, biological features vary widely. The results of conventional treatment are considered unsatisfactory in aggressive forms, with subsets of patients having short life expectancies. Relying on wide experimental evidence and more feeble clinical data, some research groups have used autologous hematopoietic stem cell transplantation (HSCT) in the most disabling autoimmune diseases with the aim of resetting the patient's immune system. Immunoablative conditioning regimens are preferred over their myeloablative counterparts, and some form of in vivo and/or ex vivo T-cell depletion is generally adopted. Despite 15 years' experience, published controlled clinical trials are still lacking, with the evidence so far available coming from pilot studies and registry surveys. In multiple sclerosis, clinical improvement, or at least lasting disease stabilization, can be achieved in the majority of the patients; nevertheless, the worst results are observed in patients with progressive disease, where no benefit can be expected from conventional therapy. Concerning rheumatologic diseases, wide experience has been acquired in systemic sclerosis, with long-term improvements in cutaneous disease being frequently reported, although visceral involvement remains unchanged at best. Autografting has proved to be barely effective in rheumatoid arthritis and quite toxic in juvenile idiopathic arthritis, whereas it leads to clinical remission and the reversal of visceral impairment in the majority of patients with systemic lupus erythematosus. A promising indication is Crohn's disease, in which long-term endoscopic remission is frequently observed. Growing experience with autologous HCST in autoimmune diseases has progressively reduced concerns about transplant-related mortality and secondary myelodysplasia/leukemia. Therefore, a sustained complete remission seems to be within the reach of autografting in some autoimmune diseases; in others, the indications, risks and benefits of autografting need to be better defined. Consequently, the search for new drugs should also be encouraged.

Stem cell transplantation for the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is comprised of ulcerative colitis and Crohn's disease and characterized by chronic inflammation of the intestinal tract. The etiology of IBD is still unknown. Traditional treatment mainly controls active inflammation and regulates immunologic derangements. Commonly used drugs include 5-aminosalicylic acid, glucocorticoid and immunosuppressant. Some cases of IBD require surgical treatment eventually. Due to multipe etiologies, IBD should be managed comprehensively. The appearance of biological agents, genetically modified methods, anticoagulant therapies, and stem cell transplantation therapies has made it more likely to cure IBD. Stem cell transplantation represents a new type of treatment for IBD. In this article, we review the role of stem cell transplantation in the treatment of IBD.

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.

Intestinal stem cells and epithelial-mesenchymal interactions in the crypt and stem cell niche

The intestinal epithelium contains a rapidly proliferating and perpetually differentiating epithelium. The principal functional unit of the small intestine is the crypt-villus axis. Stem cells located in the crypts of Lieberkühn give rise to proliferating progenitor or transit amplifying cells that differentiate into the 4 major epithelial cell types. The study of adult gastrointestinal tract stem cells has progressed rapidly with the recent discovery of several putative stem cell markers. Substantial evidence suggests 2 populations of stem cells: long-term quiescent (reserved) and actively cycling (primed) stem cells. These cells are in adjoining locations and are presumably maintained by the secretion of specific proteins generated in a unique microenvironment or stem cell niche surrounding each population. The relationship between these 2 populations, as well as the cellular sources and composition of the surrounding environment, remains to be defined, and is an active area of research. In this review, we will outline progress in identifying stem cells and in defining epithelial-mesenchymal interactions in the crypt. We will summarize early advances using stem cells for therapy of gastrointestinal disorders.

Stem cells as potential therapeutic targets for inflammatory bowel disease

The incidence and prevalence of Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD), are rising. According to some estimates >1 million new cases of IBD arise in the United States annually. The conventional therapies available for IBD range from anti-inflammatory drugs to immunosuppressive agents, but these therapies generally fail to achieve satisfactory results due to their side effects. Interest in a new therapeutic option, that is, biological therapy, has gained much momentum recently due to its focus on different stages of the inflammatory process. Stem cell (SC) research has become a new direction for IBD therapy due to our recent understanding of cell populations involved in the pathogenic process. To this end, hematopoietic and mesenchymal stem cells are receiving more attention from IBD investigators. The intestinal environment, with its crypts and niches, supports incoming embryonic and hematopoietic stem cells and allows them to engraft and differentiate. The above findings suggest that, in the future, SC-based therapy will be a promising alternative to conventional therapy for IBD. In this review, we discuss SCs as potential therapeutic targets for future treatment of IBD.

Inflammatory bowel disease: Moving toward a stem cell-based therapy

The incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel diseases (IBD), are rising in western countries. The modern hygienic lifestyle is probably at the root of a disease where, in genetically susceptible hosts, the intestinal commensal flora triggers dysregulated immune and inflammatory responses. Current therapies ranging from anti-inflammatory drugs to immunosuppressive regimens, remain inadequate. Advances in our understanding of the cell populations involved in the pathogenetic processes and recent findings on the regenerative, trophic and immunoregulatory potential of stem cells open new paths in IBD therapy. Hematopoietic and mesenchymal stem cells are catalyzing the attention of IBD investigators. This review highlights the pivotal findings for stem cell-based approaches to IBD therapy and collects the encouraging results coming in from clinical trials.

Inflammatory bowel disease: Moving toward a stem cell-based therapy

The incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel diseases (IBD), are rising in western countries. The modern hygienic lifestyle is probably at the root of a disease where, in genetically susceptible hosts, the intestinal commensal flora triggers dysregulated immune and inflammatory responses. Current therapies ranging from anti-inflammatory drugs to immunosuppressive regimens, remain inadequate. Advances in our understanding of the cell populations involved in the pathogenetic processes and recent findings on the regenerative, trophic and immunoregulatory potential of stem cells open new paths in IBD therapy. Hematopoietic and mesenchymal stem cells are catalyzing the attention of IBD investigators. This review highlights the pivotal findings for stem cell-based approaches to IBD therapy and collects the encouraging results coming in from clinical trials.

Concurrent inflammatory bowel disease and myelodysplastic syndrome: report of nine new cases and a review of the literature

Nine patients with concurrent myelodysplastic syndrome (MDS) and inflammatory bowel disease (IBD) were examined. Median age at diagnosis of these patients was similar to the usual age of patients at diagnosis of IBD only. There was a strong predominance of Crohn's disease (seven of nine cases), with an unusually high frequency of colorectal involvement (five of nine cases). Inflammatory bowel disease was diagnosed first in one patient, MDS first in five patients, and both diseases were diagnosed simultaneously in three patients. All patients had moderate or severe anemia. The prognosis of IBD was determined by MDS. These observations suggest that there is an unclear common pathogenesis of IBD and MDS and, consequently that patients with IBD and anemia of non-obvious origin should be evaluated for the presence of MDS.

Stem cells as potential novel therapeutic strategy for inflammatory bowel disease

Hematopoietic stem cell transplantation and mesenchymal stromal cell therapy are currently under investigation as novel therapies for inflammatory bowel diseases. Hematopoietic stem cells (HSC) are thought to repopulate the immune system and reset the immunological response to luminal antigens. Mesenchymal stromal cells (MSC) are cells that have the capacity to differentiate into wide variety of distinct cell lineages and suppress immune responses in vitro and in vivo. Recent results from animal models and early human experience in graft-versus-host disease but also Crohn's Disease suggest that ex vivo expanded MSCs may have clinically useful immunomodulatory effects.

Treatment of intractable ulcerating enterocolitis of infancy by allogeneic bone marrow transplantation

BACKGROUND & AIMS

Intractable ulcerating enterocolitis of infancy (IE) is an uncommon, autosomal-recessive, and devastating inflammatory bowel disorder that arises as a consequence of a poorly defined underlying immunologic disorder. Infants with IE suffer from recurrent severe oro-anal disease and an enterocolitis that is unresponsive to conventional immunosuppressive therapy and requires early pancolectomy to control the severity of the disease. Despite such aggressive treatment these individuals remain at high risk of Epstein-Barr virus-driven lymphomatous proliferations, including non-Hodgkin's lymphoma. The underlying genetic basis for this disease remains undefined. This report aims to describe the use of bone marrow transplantation as a treatment for this condition.

METHODS

This was a case series report.

RESULTS

We describe the successful treatment of IE by allogeneic bone marrow transplantation in 2 brothers, now aged 7 and 11 years, one of whom had developed an Epstein-Barr virus-related monomorphous B-lymphocyte lymphoproliferative disorder. This treatment has resulted in prolonged clinical remission in both boys and abrogated the need for aggressive immunosuppression.

CONCLUSIONS

Bone marrow transplantation can be used for the treatment of intractable ulcerating enterocolitis of infancy, which may support a role in other intractable inflammatory bowel conditions in the pediatric population.

Review article: Stem cell transplantation for the treatment of gastrointestinal diseases--current applications and future perspectives

BACKGROUND

Haematopoietic stem cell transplantation (HSCT) can be used to cure or ameliorate a variety of non-malignant diseases. These range from inherent defects of haematopoiesis, through metabolic diseases, to severe autoimmune diseases. The rationale for this strategy is based on the concept of immunoablation using high-dose chemotherapy, with subsequent regeneration of naïve T-lymphocytes derived from reinfused haematopoietic progenitor cells. Possibly the use of SCT allows the administration of high-dose chemotherapy resulting in a prompt remission in these therapy-refractory patients.

AIM

This review highlights the major scientific developments and defines the areas of successful use of HSCT in gastrointestinal disorders and gives a perspective on possible future applications.

METHODS

A search in the Medline has been conducted and all relevant published data were analysed.

RESULTS

HSCT has been proved successful in treating refractory Crohn's disease. A selected group of refractory coeliac patients having a high risk of developing enteropathy associated T-cell lymphoma has been recently treated with promising results. In cryptogenic cirrhosis, basic research and unpublished data concerning mesenchymal SCT are encouraging.

CONCLUSION

In refractory autoimmune gastrointestinal diseases, it seems that high-dose chemotherapy followed by HSCT is feasible and safe and might result in long-term improvement of disease activity.

Management of Perianal Crohn's Disease

Perianal manifestations of Crohn's disease usually coexist with active inflammation of other primary sites of the disease. Although treatment of active proximal disease may sometimes alleviate perianal symptoms, it is reasonable to separately treat symptomatic perianal disease. The diversity of perianal manifestations in Crohn's disease mandates a tailored, individualized approach in every case. Medical therapy is the best treatment option for hemorrhoids and anal fissures. The medical management of patients with perianal Crohn's disease includes the use of systemic antibiotics, immunosuppressive agents, and infliximab. Infliximab is now recognized as a very efficacious agent for treating fistulizing Crohn's disease, including perianal fistulae. It may also reduce the need for surgical intervention in specific cases. Abscesses and fistulae are treated by control of sepsis, resolution of inflammation and optimal preservation of continence, and quality of life. Abscesses require surgical drainage that may need to be prolonged to achieve complete healing. Fistulae may be treated medically, especially in cases of concurrent proctitis. Refractory fistulae may require surgical treatment including an occasional need for fecal diversion or proctectomy. The role of new treatment options such as natalizumab and CDP571 is evolving and requires further investigation.

Autologous hematopoietic stem cell transplantation in patients with refractory Crohn's disease

BACKGROUND & AIMS

Crohn's disease (CD) is an immunologically mediated inflammatory disease of the gastrointestinal tract. Due to a high morbidity and/or an increase in mortality in refractory cases, a new treatment approach is needed. In theory, maximum immune ablation by autologous hematopoietic stem cell transplantation (HSCT) can induce a remission.

METHODS

We conducted a phase 1 HSCT study in 12 patients with refractory CD. Candidates were younger than 60 years of age with a Crohn's Disease Activity Index (CDAI) of 250-400 despite conventional therapies including infliximab. Peripheral blood stem cells were mobilized with cyclophosphamide and granulocyte colony-stimulating factor and CD34 + enriched. The immune ablative (conditioning) regimen consisted of 200 mg/kg cyclophosphamide and 90 mg/kg equine antithymocyte globulin.

RESULTS

The procedure was well tolerated with anticipated cytopenias, neutropenic fever, and disease-related fever, diarrhea, anorexia, nausea, and vomiting. The median days for neutrophil and platelet engraftment were 9.5 (range, 8-11) and 9 (range, 9-18), respectively. The initial median CDAI was 291 (range, 250-358). Symptoms and CDAI improved before hospital discharge, whereas radiographic and colonoscopy findings improved gradually over months to years following HSCT. Eleven of 12 patients entered a sustained remission defined by a CDAI < or =150. After a median follow-up of 18.5 months (range, 7-37 months), only one patient has developed a recurrence of active CD, which occurred 15 months after HSCT.

CONCLUSIONS

Autologous HSCT may be performed safely and has a marked salutary effect on CD activity. A randomized study will be needed to confirm the efficacy of this therapy.

Stem cell transplantation for Crohn's disease

There is much interest in the possibility that haematopoietic stem cell transplantation might benefit patients with inflammatory bowel disease, with an emphasis on Crohn's disease. Case reports of patients with Crohn's disease undergoing stem cell transplantation for other reasons, or specifically for Crohn's disease, support the view that major improvements can be achieved, with even the possibility of a cure in a small number of, but certainly not all, cases. The development of Crohn's disease in a previously normal patient receiving an allogeneic transplant from an individual with the NOD2 mutation illustrates the importance of the genotype of the immune system. Population of the lamina propria by myofibroblasts with the donor's phenotype shows that non-immune mechanisms make also play a part. A clinical trial to determine the value of stem cell transplantation in Crohn's disease has been set up under the supervision of the European Group for Blood and Marrow Transplantation.

Haematopoietic stem cell transplantation for autoimmune disorders: the American perspective

The hypothesis that haematopoietic stem cell transplantation (HSCT) might be useful in treating refractory autoimmune diseases (AID) was suggested by studies in animal models and by the improvement of concurrent autoimmune diseases in patients who had undergone transplantation for haematological disorders. This concept has now been tested in a substantial number of phase I/II clinical trials of autologous HSCT. These early results are promising, even in patients who have failed on multiple standard therapies for AID. Transplantation-related toxicity has decreased with growing experience in the application of this procedure, better patient selection and the modification of treatment protocols. Randomized trials currently under way or under consideration should clarify the role of HSCT in patients with autoimmune disorders.

Novel biologics in inflammatory bowel disease

Understanding of immunologic mechanisms involved in the initiation and perpetuation of chronic inflammation has led to new therapeutic opportunities in the inflammatory bowel diseases. The term "biologics" is used to distinguish new biotechnologic therapeutics from the conventional drugs used in the treatment of immune-mediated inflammatory disorders. This article reviews novel biologic therapies that are being investigated for the treatment of Crohn's disease and ulcerative colitis.