Novel strategies for steroid-refractory acute graft-versus-host disease

Treatment Options in Steroid-Refractory Acute Graft-Versus-Host Disease Following Hematopoietic Stem Cell Transplantation

Objective:

To evaluate the treatment options in steroid-refractory acute graft-versus-host disease (GVHD) following hematopoietic stem cell transplantation.

Data Sources:

Literature was obtained by searching MEDLINE (1966–May 2007) and EMBASE (1980–May 2007).

Study Selection and Data Extraction:

All pertinent clinical trials, retrospective studies, case reports, and compassionate use studies were identified and evaluated for safety and efficacy of the pharmacologic agents.

Data Synthesis:

Steroid-refractory acute GVHD is associated with high rates of morbidity and mortality. Although various pharmacologic agents have been studied in the treatment of steroid-refractory acute GVHD, no treatments have been established as a salvage therapy. Preliminary data on different pharmacologic agents have been identified and evaluated for their efficacy and tolerability in the treatment of steroid-refractory acute GVHD. The effects of the pharmacologic agents varied significantly among patients: severity of the disease, involvement of different organs, and the patient's age seem to be the major factors that affect an individual's response to drug therapy. In addition, the treatments are further challenged by the high incidence of potentially fatal opportunistic infections that occur during the therapy.

Conclusions:

Selection of pharmacologic agents for the treatment of steroid-refractory acute GVHD should be based on the target organs, adverse drug reactions, and economic factors. Further studies with larger sample sizes are warranted to better understand the roles of these agents in the treatment of steroid-refractory acute GVHD.

Systematic review and meta-analysis of prospective studies for ECP treatment in patients with steroid-refractory acute GVHD

PURPOSE

The aim of this systematic review was to evaluate the efficacy and safety of extracorporeal photopheresis (ECP) treatment in patients with steroid-refractory acute graft-versus-host disease (SR-aGVHD).

METHODS

An electronic search was carried out on the MEDLINE, EMBASE, Science Citation Index (SCI), and Cochrane Library databases. We included prospective clinical trials in SR-aGVHD treated by ECP. The main endpoints consisted of mortality, exacerbation, or response.

RESULTS

Only seven studies involving 121 patients met the inclusion criteria for further review. Our analysis showed positive results of ECP for aGVHD. The overall response rate (ORR) was 0.71 and the complete response rate (CRR) was 0.71. The efficacy of ECP for skin aGVHD, liver aGVHD, and gut aGVHD were 0.86, 0.60, and 0.68, respectively. However, no sufficient evidence verifies the exact benefit in this review, because the number of patients enrolled in trials is limited and publish bias exists.

CONCLUSION

ECP is an effective therapy for skin, liver, and gut aGVHD, and large double-blind clinical trials are required to prove the outcome of this meta-analysis.

Intra-arterial methylprednisolone for severe steroid refractory gastrointestinal graft-versus-host disease

Acute graft versus host disease (GVHD) is a significant complication of bone marrow transplantation with approximately half of patients being refractory to steroids. There are numerous second-line systemic immunosuppressive treatments but the overall prognosis is poor and these therapies are associated with high mortality due to infection. An alternative approach to systemic treatment for GVHD is targeted delivery of immunosuppression. We present two pediatric cases with steroid-refractory gastrointestinal GVHD who clinically responded to intra-arterial steroid administration. We also review the literature regarding this treatment modality with a particular emphasis in children.

Intramesenteric steroid treatment for steroid- refractory gastrointestinal graft versus host disease

Currently, steroid-refractory severe gastrointestinal (GI) graft versus host disease (GVHD) is among the most important complications of allogeneic transplantation, and as yet there is no standard approach to its treatment. Herein we report two cases with steroid-refractory GI GVHD that received intramesenteric steroid treatment. In both cases the frequency and volume of diarrhea resolved completely following intramesenteric methylprednisolone (MP) injection. In conclusion, intra-arterial steroid injection might be an alternative treatment approach for steroid-refractory GI GVHD.

Conflict of interest:None declared.

Loss of endothelial thrombomodulin predicts response to steroid therapy and survival in acute intestinal graft-versus-host disease

Steroid-refractory graft-versus-host disease causes significant morbidity and mortality after allogeneic stem cell transplantation. The pathomechanism of steroid resistance is currently not understood, but it has been suggested that endothelial cell dysfunction plays a role. Endothelial thrombomodulin was quantified along with histological markers of epithelial damage and cytotoxic T cells in colon biopsies from 51 allografted patients, and retrospectively correlated with response to steroids and survival. Loss of endothelial thrombomodulin was the strongest predictor of response to steroids (P=0.02) and nonrelapse mortality (P=0.01) in multivariate analyses adjusting for T-cell infiltrates, histological grading, vessel density, disease status, donor type, and conditioning therapy. Our data provide evidence that at disease onset, loss of endothelial thrombomodulin expression rather than excessive T-cell infiltration associates with steroid-refractory graft-versus-host disease and mortality. Prospective histological investigations are now warranted to improve diagnosis and prognostication of this core complication of stem cell transplantation.

Approaches for immunological tolerance induction to stem cell-derived cell replacement therapies

The shortage of donors for organ transplantation and also to treat degenerative diseases has led to the development of the new field of regenerative medicine. One aim of this field, in addition to in vivo induction of endogenous tissue regeneration, is to utilize stem cells as a supplementary source of cells to repair or replace tissues or organs that have ceased to function owing to ageing or autoimmunity. Embryonic stem cells hold promise in this respect because of their developmental capacity to generate all tissues within the body. More recently, the discovery of induced pluripotent stem cells, somatic cells reprogrammed to a primitive embryonic-like state by the introduction of pluripotency factors, may also act as an important cell source for cell replacement therapy. However, before cell replacement therapy can become a reality, one must consider how to overcome the potential transplant rejection of stem cell-derived products. There are several potential ways to circumvent the hurdles presented by the immune system in this setting, not least the induction of immunological tolerance in the host. In this review, we consider this and other approaches for engendering acceptance of stem cell-derived tissues.

Consensus Conference on Clinical Practice in Chronic GVHD: Second-Line Treatment of Chronic Graft-versus-Host Disease

Steroid refractory chronic graft-versus-host disease (cGVHD) is associated with a significant morbidity and mortality. Although first-line treatment of cGVHD is based on controlled trials, second-line treatment is almost solely based on phase II trials or retrospective analyses. The consensus conference on clinical practice in cGVHD held in Regensburg aimed to achieve a consensus on the current evidence of treatment options as well as to provide guidelines for daily clinical practice. Treatment modalities are the use of steroids and calcineurin inhibitors as well as immunomodulating modalities (photopheresis, mTOR-inhibitors, thalidomide, hydroxychloroquine, vitamin A analogs, clofazimine), and cytostatic agents (mycophenolate mofetil, methotrexate, cyclophosphamide, pentostatin). Recent reports showed some efficacy of rituximab, alemtuzumab, and etanercept in selected patients. Moreover, tyrosine kinase inihibitors such as imatinib came into the field because of their ability to interfere with the platelet-derived growth factor (PDGF-R) pathway involved in fibrosis. An other treatment option is low-dose thoracoabdominal irradiation. Although different treatment options are available, the "trial-and-error system" remains the only way to identify the drug effective in the individual patient, and valid biomarkers are eagerly needed to identify the likelihood of response to a drug in advance. Moreover, the sparse evidence for most treatment entities indicates the urgent need for systematic evaluation of second-line treatment options in cGVHD.

Mesenchymal stem cells prevent the rejection of fully allogenic islet grafts by the immunosuppressive activity of matrix metalloproteinase-2 and -9

OBJECTIVE

Mesenchymal stem cells (MSCs) are known to be capable of suppressing immune responses, but the molecular mechanisms involved and the therapeutic potential of MSCs remain to be clarified.

RESEARCH DESIGN AND METHODS

We investigated the molecular mechanisms underlying the immunosuppressive effects of MSCs in vitro and in vivo.

RESULTS

Our results demonstrate that matrix metalloproteinases (MMPs) secreted by MSCs, in particular MMP-2 and MMP-9, play an important role in the suppressive activity of MSCs by reducing surface expression of CD25 on responding T-cells. Blocking the activity of MMP-2 and MMP-9 in vitro completely abolished the suppression of T-cell proliferation by MSCs and restored T-cell expression of CD25 as well as responsiveness to interleukin-2. In vivo, administration of MSCs significantly reduced delayed-type hypersensitivity responses to allogeneic antigen and profoundly prolonged the survival of fully allogeneic islet grafts in transplant recipients. Significantly, these MSC-mediated protective effects were completely reversed by in vivo inhibition of MMP-2 and MMP-9.

CONCLUSIONS

We demonstrate that MSCs can prevent islet allograft rejection leading to stable, long-term normoglycemia. In addition, we provide a novel insight into the mechanism underlying the suppressive effects of MSCs on T-cell responses to alloantigen.

Fototerapia na doença enxerto contra hospedeiro

FUNDAMENTOS: A doença enxerto contra hospedeiro é um dos obstáculos ao sucesso do transplante de medula óssea, e o envolvimento cutâneo é freqüente. A fototerapia é utilizada devido à intensa atividade imunomoduladora local, sendo opção terapêutica adjuvante para as lesões cutâneas resistentes à terapia convencional. OBJETIVO: Realizar análise descritiva do tratamento da doença enxerto contra hospedeiro com fototerapia (Puva ou UVB de faixa estreita). MÉTODOS: Foram atendidos nove pacientes com manifestação cutânea da doença enxerto contra hospedeiro aguda ou crônica. Seis foram tratados com Puva, terapia de primeira escolha, e três com UVB de faixa estreita. As sessões foram realizadas três vezes por semana, e a resposta terapêutica avaliada após 12 sessões. RESULTADOS: Todos os pacientes com doença enxerto contra hospedeiro aguda mostraram melhora, com desaparecimento do eritema e do edema. Naqueles com doença crônica, observaram-se involução das lesões liquenóides e melhora da mobilidade daqueles com a forma esclerodermiforme. Dois pacientes apresentaram doença de evolução grave e foram a óbito. CONCLUSÃO: A fototerapia mostrou-se efetiva no tratamento das manifestações cutâneas da doença enxerto contra hospedeiro aguda e crônica. A Puva permite o controle da doença, podendo a UVB de faixa estreita ser opção para pacientes impossibilitados de usar medicação sistêmica.

Effective delivery of antisense peptide nucleic acid oligomers into cells by anthrax protective antigen

Peptide nucleic acid (PNA) is highly stable and binds to complementary RNA and DNA with high affinity, but it resists cellular uptake, thereby limiting its bioavailability. We investigated whether protectiveantigen (PA, a non-toxic component of anthrax toxin) could transport antisense PNA oligomers into reporter cells that contain luciferase transgenes with mutant beta-globin IVS2 intronic inserts, which permit aberrant pre-mRNA splicing and impair luciferase expression. PNA oligomers antisense to mutant splice sites in these IVS2 inserts induced luciferase expression when effectively delivered into the cells. PNA 18-mers with C-terminal poly-lysine tails [PNA(Lys)(8)] demonstrated modest sequence-specific antisense activity by themselves at micromolar concentrations in luc-IVS2 reporter cell cultures. However, this activity was greatly amplified by PA. Antisense PNA(Lys)(8) with but not without PA also corrected the IVS2-654 beta-globin splice defect in cultured erythroid precursor cells from a patient with beta-thalassemia [genotype, IVS2-654(beta(0)/beta(E))], providing further evidence that anthrax PA can effectively transport antisense PNA oligomers into cells.

Graft versus host disease after liver transplantation - a single center experience and review of literature

Graft versus host disease (GvHD) after liver transplantation has an incidence of 0.1-1%. It is an infrequent but severe and mostly lethal complication. Approximately, 80 cases have been reported in literature so far. A single center experience is reported retrospectively. We performed a retrospective analysis of 1815 liver transplants in our center, transplanted over a period of 17 years. Five patients (5/1815 = 0.28%) with histologically diagnosed GvHD were included in the analysis. Onset of GvHD was between postoperative day (POD) 20 and 60. All patients developed skin rash, being the first symptom in four cases; one patient had joint pain as initial symptom. Macrochimerism was confirmed in all patients. Treatment consisted of augmentation of baseline immunosuppression (n = 4), methylprednisolone (n = 4), and T-cell depleting antibodies (n = 3). One patient received no specific therapy because of her deleterious condition. All patients died because of either haemorrhage or uncontrollable infections. In our experience, GvHD has been an extremely rare, albeit deleterious clinical condition, which was resistant to classical immunosuppressive rescue regimens.

Management of acute graft-versus-host disease

Acute graft-versus-host disease (GvHD) is a frequent complication of allogeneic haemopoietic stem cell transplantation (HSCT) and donor lymphocyte infusions (DLI). Its incidence and severity depends on several factors, such as prophylaxis method, donor/recipient matching, intensity of the conditioning regimen and composition of the graft. Significant progress has been made in recent years in understanding the pathogenesis of the disease, and some of these advances have been translated into clinical trials. First-line treatment of acute GvHD is based on corticosteroids, and produce sustained responses in 50-80% of patients depending on the initial severity. Non-responders are offered second-line therapy, with combinations of immunosuppressive agents, but 1-year survival is 30% in most large trials. New strategies explored include infusion of expanded mesenchymal stem cells (MSC), down regulation of antigen-presenting cells (APC) and suicide gene transduced T cells. Acute GvHD is complicated by severe immunodeficiency causing life-threatening infections. To date, GvHD has not been differentiated from the graft-versus-leukaemia effect. The present review will discuss some of these aspects.

Role of intra-arterial steroid administration in the management of steroid-refractory acute gastrointestinal graft-versus-host disease

We report here a case of severe steroid-refractory gastrointestinal graft-versus-host disease treated with intra-arterial administration of corticosteroids. A 53-year-old female with non-Hodgkin's lymphoma received peripheral blood hematopoietic stem cell transplant from her HLA-matched sibling. She developed grade II skin and grade IV gastrointestinal graft-versus-host disease with no hepatic involvement. Therapy with oral prednisone easily controlled her skin rash but she had profuse diarrhea that did not respond to high dose intravenous corticosteroids and denileukin diftitox. Infusion of methyl-prednisolone into superior and inferior mesenteric arteries produced dramatic improvement of diarrhea, with complete resolution of gastrointestinal graft-versus-host disease.

Update on the management of acute graft-versus-host disease

PURPOSE OF REVIEW

Acute graft-versus-host disease is one of the commonest complications after allogeneic stem cell transplantation. Recent advances in its prevention and therapy are giving new hope to patients with this disease. This review covers the major advances in prophylaxis and therapy for this problem.

RECENT FINDINGS

The use of novel approaches for prophylaxis such as posttransplant cyclophosphamide and non-methotrexate-containing regimens is discussed. The results of therapy with new agents such as pentostatin, pulse cyclophosphamide, long-wavelength ultraviolet A phototherapy, and monoclonal antibodies such as denileukin diftitox or etanercept are reviewed.

SUMMARY

Without question, outcome in patients who develop graft-versus-host disease is improving. With better supportive care, and more effective prophylaxis and therapy, these patients have an improved chance for full recovery. Patients should be enrolled, when possible, in studies aimed to prevent and treat graft-versus-host disease.

Mycophenolate Mofetil Is Effective and Well Tolerated in the Treatment of Refractory Acute and Chronic Graft-versus-Host Disease

We enrolled 11 patients with refractory graft-versus-host disease (GVHD) in a prospective trial evaluating the efficacy of mycophenolate mofetil (MMF). Four (67%) of the 6 patients with acute GVHD and all 5 patients with chronic GVHD responded to MMF. Ten (91%) of the 11 patients were able to decrease steroid use (median decrease, 86%; range, 25%-100%). After a median follow-up of 18 months (range, 1-65 months), 7 patients (64%) remained alive. The adverse events were infectious complications (36%), diarrhea (27%), and neutropenia (18%); the only patient discontinuing MMF did so because of grade 4 neutropenia. This preliminary study suggests that MMF is a well-tolerated agent and has a beneficial effect in the treatment of refractory acute and chronic GVHD.

Approaches to graft-vs-host disease

Graft-vs-host disease (GVHD) is one of the most difficult problems in stem cell transplantation. It is best considered in the context of the normal immune response. The role of the immune system is to identify and eliminate foreign antigens. In the case of GVHD, the antigens are minor histocompatibility antigens (mHA) recognized in an inflammatory milieu. The immune system cannot reasonably be expected to selectively recognize microbial antigens and ignore mHA. This approach would require the generation of selective tolerance--something that clearly occurs but which we have frustratingly little control over. While we can often treat and remit even life-threatening GVHD, the consequence has been the development of fatal opportunistic infections. The challenge is to change our style of thinking about GVHD to allow a transition from a 'nuclear winter' approach that controls GVHD at the price of infection, to a more selective patient approach that recognizes the limitations of immunosuppressive therapy.

Current status of hematopoietic stem cell transplantation after nonmyeloablative conditioning

PURPOSE OF REVIEW

Allogeneic hematopoietic stem cell transplantation was originally developed as a form of rescue from high-dose chemoradiotherapy, which is given both to eradicate malignancy and provide sufficient immunosuppression for allogeneic engraftment. However, it was observed that allogeneic immunocompetent cells transplanted with the stem cells, or arising from them, mediated therapeutic antitumor effects independent of the action of the high-dose therapy. This was termed a graft-versus-tumor effect. This has prompted the recent development of nonmyeloablative conditioning regimens for allogeneic hematopoietic stem cell transplantation that have opened the way to include elderly patients and those with comorbid conditions.

RECENT FINDINGS

Recent retrospective studies comparing hematopoietic stem cell transplantation after myeloablative or nonmyeloablative regimens suggested that the use of nonmyeloablative conditioning might be associated with lower transplant-related toxicity, lower nonrelapse mortality, and at least similar intermediate-term progression-free survival.

SUMMARY

Hematopoietic stem cell transplantation after nonmyeloablative conditioning might become the procedure of choice also for younger patients. Phase 3 studies are needed to determine outcomes for different diseases and age groups.

The influence of the conditions of hematopoietic cell transplantation on infectious complications

PURPOSE OF REVIEW

The multitude of factors that influence the risk of infection after hematopoietic cell transplantation has been further complicated by the rapid evolution of this therapy in the past 5 years. The degree to which functional immune reconstitution has been achieved reflects the equilibrium reached by the immune systems of the recipient and donor in the context of host non-hematopoietic tissue. Thus immunomodulatory influences on the recipient and the transplanted graft, both before and after hematopoietic cell transplantation, have a profound influence on the incidence and severity of infection. This review of the recent literature contributes to our understanding of how the conditions of hematopoietic cell transplantation influence the timing and nature of infectious complications.

RECENT FINDINGS

The main themes of published primary research from 2004 to the present focus on non-myeloablative conditioning regimens and their effects on immune reconstitution after hematopoietic cell transplantation.

SUMMARY

A plethora of clinical trials are ongoing, focused on the outcome after conditioning regimens designed to result in less regimen-related toxicity while preserving or enhancing the graft-versus-tumor effect. Given the infancy of these new approaches, it is not possible to make definitive statements regarding the relative risk of serious infection with each therapy. It is clear that a reduction in regimen-related non-infectious complications or mortality does not necessarily ensure a reduction in clinically significant infections. Improvements in early diagnostic and therapeutic options for these infections now bring us to an era of understanding pathogens as probes of the functional reconstitution of immunity.

Efficacy of the interleukin-2 receptor antagonist basiliximab in steroid-refractory acute graft-versus-host disease

Acute graft-versus-host disease (aGVHD) occurs in up to 80% of patients who undergo allogeneic stem cell transplantation (SCT) and contributes significantly to transplant-related mortality (TRM). We conducted a prospective phase II trial to assess the efficacy and feasibility of treating steroid-refractory aGVHD with basiliximab, a chimaeric monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor. Basiliximab was administered intravenously at a dose of 20 mg on days 1 and 4. Twenty-three patients were enrolled between October 1999 and July 2004. We found a primary overall response rate of 82.5% with four patients (17.5%) showing a complete response and 15 patients (65%) a partial response. Six patients were again treated successfully with an IL-2 receptor antagonist because of recurrence of aGVHD. The rates of infections, chronic GVHD, malignancy recurrence and 1-year TRM following immunosuppression with basiliximab were comparable with those found with other treatment modalities for aGVHD. We conclude that basiliximab is efficient and feasible for steroid-refractory aGVHD and merits further evaluation.