Extracorporeal photopheresis for the treatment of steroid refractory acute GVHD

Modified extracorporeal photopheresis with cells from a healthy donor for acute graft-versus-host disease in a mouse model

Background

Graft-versus-host disease (GvHD) is a major challenge after hematopoietic stem cell transplantation but treatment options for patients are still limited. In many cases first-line treatment with glucocorticoids is not successful. Among second-line therapies the extracorporeal photopheresis (ECP) is frequently performed, due to induction of selective tolerance instead of general immunosuppression. However, for some patients with severe acute GvHD the leukapheresis step of the ECP procedure is physically exhausting and limits the number of ECP cycles.

Methods

We hypothesized that leukocytes from healthy cell donors could be used as a replacement for ECP leukocytes gained from the GvHD patient. For this purpose we used a well established mouse model of acute GvHD. The ECP therapy was based on cells with the genetic background of the initial donor of the stem cell transplantation. As a precondition we developed a protocol representing conventional ECP in mice equivalent to clinical used ECP setup.

Results

We could demonstrate that conventional, clinically derived ECP setup is able to alleviate acute GvHD. By using leukocytes obtained from healthy mice with the bone marrow donor’s genetic background we could not observe a statistically significant therapeutic effect.

Conclusions

Conventional human ECP setup is effective in the mouse model of severe acute GvHD. In addition we could not prove that ECP cells from healthy mice with bone marrow donor’s genetic background are as effective as ECP cells derived from GvHD mice. Based on our findings, new questions arise for further studies, in which the cellular characteristics for ECP mediated immune tolerance are a matter of investigation.

Guidelines on the use of extracorporeal photopheresis

BACKGROUND

After the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma was published in 1983 with its subsequent recognition by the FDA for its refractory forms, the technology has shown significant promise in the treatment of other severe and refractory conditions in a multi-disciplinary setting. Among the major studied conditions are graft versus host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection and inflammatory bowel disease.

MATERIALS AND METHODS

In order to provide recognized expert practical guidelines for the use of this technology for all indications the European Dermatology Forum (EDF) proceeded to address these questions in the hands of the recognized experts within and outside the field of dermatology. This was done using the recognized and approved guidelines of EDF for this task.

RESULTS AND CONCLUSION

These guidelines provide at present the most comprehensive available expert recommendations for the use of extracorporeal photopheresis based on the available published literature and expert consensus opinion.

Extracorporeal photopheresis (photochemotherapy) in the treatment of acute and chronic graft versus host disease: immunological mechanisms and the results from clinical studies

Extracorporeal photopheresis (ECP) is an immunomodulatory alternative for treatment of graft versus host disease (GVHD). The blood is then separated into its various components through apheresis; buffy coat cells are thereafter treated with 8-methoxypsoralen before exposure to ultraviolet light and finally reinfused into the patient. There is a general agreement that this treatment has an anti-GVHD effect, but the mechanisms of action behind this effect are only partly understood. However, altered maturation of dendritic cells (DC) and thereby indirect modulation of T-cell reactivity seems to be one important mechanism together with DC-presentation of antigens derived from apoptotic donor T cells and induction of regulatory T cells. The treatment has been best studied in patients with chronic GVHD (both pediatric and adult patients), but most studies are not randomized and it is difficult to know whether the treatment is more effective than the alternatives. The clinical studies of ECP in adults with acute GVHD are few and not randomized; it is not possible to judge whether this treatment should be a preferred second- or third-line treatment. There is no evidence for increased risk of leukemia relapse or suppression of specific graft versus leukemia reactivity by this treatment, so specific antileukemic immunotherapy may still be possible. Thus, even though the treatment seems effective in patients with GVHD, further clinical (especially randomized) as well as biological studies with careful standardization of the treatment are needed before it is possible to conclude how ECP should be used in acute and chronic GVHD.

Extracorporeal photopheresis combined with pentostatin in the conditioning regimen for canine hematopoietic cell transplantation does not prevent GVHD

Extracorporeal photopheresis (ECP) and the purine analog pentostatin exert potent immunomodulatory effects. We evaluated the use of these treatment modalities to prevent GVHD in a canine model of unrelated dog leukocyte Ag-mismatched hematopoietic cell transplantation, after conditioning with 920 cGy TBI. We have shown previously in this model that 36/40 dogs given MTX alone as postgrafting immunosuppression engrafted and that 25 of 40 dogs had severe GVHD and median survival of 21 days. In the current study, nine dogs received conditioning with 920 cGy TBI and postgrafting MTX either with ECP on days -2 to -1 alone (n=5) or ECP on days -6 and -5 combined with two doses of pentostatin (days -4 to -3) (n=4). Seven of nine dogs achieved engraftment. Six dogs developed severe acute GVHD (four in the group with ECP alone and two with pentostatin and ECP). We failed to demonstrate a positive impact of ECP and pentostatin for the prevention of GVHD compared with historical control dogs.

Autologous apoptotic cells preceding transplantation enhance survival in lethal murine graft-versus-host models

Acute graft-versus-host disease (GVHD) is induced by alloreactivity of donor T cells toward host antigens presented on antigen-presenting cells (APCs). Apoptotic cells are capable of inducing tolerance by altering APC maturation. Apoptosis can be induced by extracorporeal photopheresis (ECP). We demonstrate that the use of ECP as a prophylaxis prior to conditioning significantly improves survival (P < .0001) after bone marrow transplantation (BMT) by inhibiting the initiation phase of acute GVHD in a murine BMT model. ECP-treated autologous splenocytes resulted in immune tolerance in the host, including reduced dendritic cell activation with decreased nuclear factor-κB engagement, increased regulatory T-cell (Treg) numbers with enhanced expression of cytolytic T lymphocyte-associated antigen 4, potentiating their suppressive function. The protective effect required host production of interleukin-10 and host Tregs. Conventional T cells that entered this tolerant environment experienced reduced proliferation, as well as a reduction of tissue homing and expression of activation markers. The induction of this tolerant state by ECP was obviated by cotreatment with lipopolysaccharide, suggesting that the inflammatory state of the recipient prior to treatment would play a role in potential clinical translation. The use of prophylactic ECP may provide an alternative and safe method for immunosuppression in the bone marrow transplant setting.

Treatment and management of graft-versus-host disease: improving response and survival

Graft-versus-host disease (GVHD) is a significant cause of morbidity and mortality following allogenic haematopoietic stem-cell transplantation and thus the focus of much ongoing research. Despite considerable advances in our understanding of the pathophysiology, diagnosis and predisposing factors for both acute and chronic forms of the disease, a standardised therapeutic strategy is still lacking. There is good evidence for initial treatment of both acute and chronic forms of the disease with corticosteroid therapy. However, the most effective approach to steroid-refractory disease remains controversial, with current practice based mainly on smaller studies and varying considerably between local institutions. Timely diagnosis, multidisciplinary working and good supportive care, including infection prophylaxis, are clearly important in optimizing response and survival in such patients. It is hoped that in the future systematic research strategies and the identification of novel therapeutic targets may improve outcome further. The following review aims to outline some of the existing options for the treatment and management of acute and chronic GVHD.

Extracorporeal photopheresis for treatment of adults and children with acute GVHD: UK consensus statement and review of published literature

Extracorporeal photopheresis (ECP) has been used for over 20 years to treat acute GVHD (aGVHD) and chronic GVHD. Evidence on the efficacy of response in aGVHD has continued to accrue and data suggest that there is a good response and prolonged survival in both children and adults with grade II-IV aGVHD. Unlike chronic GVHD where treatment schedules are typically one or two times monthly for 12-18 months, patients with aGVHD respond rapidly to an intense weekly treatment schedule for 8 weeks, typically allowing steroids to be discontinued without flare-ups of aGVHD. Maintenance ECP therapy is generally not required. Many centres across Europe and United States treat aGVHD with ECP as second-line therapy and responses are excellent in a subset of patients. Unlike other second-line therapies, ECP is not immunosuppressive and has no reported drug interactions. Importantly, ECP does not have a negative impact on the graft-versus-malignancy effect of the transplant. This statement aims to select those patients most likely to respond to treatment and summarises treatment and monitoring schedules for the management of aGVHD in adult and paediatric patients to ensure the correct patients are treated with the optimal protocol for efficacy.

Extracorporeal photopheresis in the management of graft-versus-host disease

QUESTION

Is there a benefit associated with the use of extracorporeal photopheresis (ecp) compared with other treatment options for patients who have received allogeneic stem-cell transplantation (sct) and are experiencing graft-versus-host disease (gvhd), if response rate, survival, or improvement in symptoms are the outcomes of interest?

PERSPECTIVES

After allogeneic sct, gvhd is a common complication historically categorized as either acute (agvhd: onset ≤100 days post-transplantation) or chronic (cgvhd: >100 days post-transplantation). Graft-versus-host disease occurs when the donor's immune cells recognize the host patient's tissues and organs as foreign and attack them, causing a multitude of problems, often in liver, gastrointestinal system, and skin. Photopheresis is one therapy that has emerged since the early 2000s for the management of steroid-refractory gvhd because of its steroid-sparing ability, low associated toxicity, and efficacy in some clinical settings. The present recommendation report summarizes the available data about photopheresis for the treatment of gvhd and provides recommendations on its use.

METHODOLOGY

The medline (Ovid) database was systematically searched for January 1995 to August 2013, and the best available evidence was used to draft recommendations relevant to adult and pediatric patients in Ontario who have received allogeneic sct and are experiencing gvhd. Draft recommendations were first reviewed by clinical and methodology experts before undergoing internal review. Final approval of this practice guideline report was obtained from both the Stem Cell Transplant Steering Committee and the Report Approval Panel of the Program in Evidence-Based Care.

RECOMMENDATIONS

These recommendations apply to adult and pediatric patients who have received an allogeneic sct and are experiencing gvhd: ecp is an acceptable therapy for the treatment of steroid-dependent or refractory agvhd in adult and pediatric patients.ecp is an effective therapy for the treatment of steroid-dependent or refractory cgvhd in adult and pediatric patients.

QUALIFYING STATEMENT

In Ontario, ecp is currently a covered therapy for patients with steroid-refractory gvhd who meet certain eligibility criteria.

Extracorporeal photopheresis: a useful therapy for patients with steroid-refractory acute graft-versus-host disease but not for the prevention of the chronic form

BACKGROUND

Extracorporeal photopheresis (ECP) has been used successfully to treat severe steroid-refractory acute and chronic graft-versus-host disease (aGVHD, cGVHD) since the late 1990s.

OBJECTIVES

To evaluate retrospectively the efficacy and safety of ECP in patients with aGVHD. We also assessed whether ECP may play a role in the prevention of cGVHD.

PATIENTS AND METHODS

Nine consecutive patients with allografts with aGVHD grade II-III, as defined by consensus criteria, and refractory to steroids, were treated with ECP. ECP was started at a median interval of 46·3 days (range 10-70) from aGVHD onset. Patients were treated initially on two consecutive days (one cycle) at 1-week intervals until improvement and then every 2 weeks. Treatment was then tapered off individually. To evaluate statistical relationships with outcome after 30, 60 and 90 days of ECP, all clinical and historical variables of the patients before treatment were analysed.

RESULTS

All patients survived and responded within 90 days. The average aGVHD score was 1·72 at aGVHD onset, 2·44 when ECP was started and then gradually declined to 0·44 on day 90. At the same time, the average dose of methylprednisolone declined from 2·22 mg kg(-1) to 0·27 mg kg(-1) (day 90), while the average dose of ciclosporin declined from 2·46 mg kg(-1) to 0·77 mg kg(-1) (day 90). Six of nine patients showed a complete skin response after 90 days of treatment. All patients with liver and gastrointestinal tract involvement had complete responses after 90 days, apart from one patient. All our patients developed cGVHD, seven of nine while still on maintenance regimen (6-13 months after haematopoietic stem cell transplantation, HSCT) and the other two patients after suspension of ECP (6 and 9 months after HSCT).

CONCLUSIONS

ECP is effective in patients with mild to moderate steroid-refractory aGVHD (grade II-III). On the other hand, ECP did not prevent the development of cGVHD in our patients.

Acute graft-versus-host disease: are we close to bringing the bench to the bedside?

Graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplant (AHSCT) associated with significant morbidity and mortality. This review focuses on the pathophysiology, prevention, and treatment of acute GVHD. Specifically, we explain how new discoveries in immunology have expanded our understanding of GVHD, in which tissue damage from chemotherapy or radiation results in cytokine release, activating T cells, resulting in proliferation and differentiation, trafficking to target organs, and tissue destruction and inflammation. Insights into the mechanisms of this disease relate directly to the development of preventive strategies and therapies, such as immunosuppression, calcineurin inhibitors, T-cell depletion, CCR5 antagonists, gut decontamination, extracorporeal photopheresis, and more. Understanding the immunobiology of GVHD and developing effective preventions and treatments are critical to the continuing success of AHSCT.

Extracorporeal photopheresis in the treatment of graft-versus-host disease: evidence and opinion

Despite significant advances in prevention and treatment strategies, graft-versus-host disease remains the most significant cause of morbidity and nonrelapse mortality after allogeneic hematopoietic cellular transplantation. Corticosteroids remain the standard frontline therapy for graft-versus-host disease; however, a considerable number of patients will not respond adequately and others will be significantly affected by adverse effects. Extracorporeal photopheresis is one of several secondary therapies which have shown promise in the clinical setting. While the procedure itself has been around for over 20 years, our understanding of the mechanisms from which therapeutic benefits are seen, and the population they are seen in, remains limited. In this article, we review the use of extracorporeal photopheresis for the treatment of graft-versus-host disease including details covering the procedure's mechanism of action, safety profile and clinical efficacy data.

Gastrointestinal acute graft-versus-host disease in children: histology for diagnosis, mesenchymal stromal cells for treatment, and biomarkers for prediction of response

Steroid-nonresponsive acute graft-versus-host disease (aGVHD) after hematopoietic stem cell transplantation carries a poor prognosis. Various groups have reported beneficial effects of mesenchymal stromal cell (MSC) infusion as salvage treatment. Response to treatment is typically evaluated using the diagnostic clinical criteria for aGVHD. In this study, we evaluated the usefulness of additional gastrointestinal biopsy specimens paired with serum biomarkers. In a cohort of 22 pediatric patients, persistent or recurrent diarrhea was seen in 18 children treated with MSC infusion for steroid-refractory aGVHD. To exclude other causes of gastrointestinal pathology, patients were biopsied for histological analysis. Eight of 12 patients exhibited residual tissue damage and villous atrophy, but no active aGVHD. Serum biomarkers have been identified as an alternative tool for monitoring the response to aGVHD treatment. The value of biomarkers for inflammation, tissue, and endothelial cell damage was evaluated in our cohort. Although predictive of response to treatment and survival, these markers lack the necessary specificity and sensitivity to predict response to MSC therapy. Objective endpoints for clinical trials on the treatment of steroid-refractory aGVHD remain to be defined. Thus, we recommend including biopsies and biomarkers to discriminate between ongoing aGVHD and postinflammatory malabsorption.

Advances in the treatment of acute graft-versus-host disease

Allogeneic hematopoietic stem cell transplantation (HSCT) has been widely used for the treatment of hematologic malignant and non-malignant hematologic diseases and other diseases. However, acute graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic transplantation. Acute GVHD may occur in 30% of transplant recipients, which is a syndrome of erythematous skin eruption, cholestatic liver disease and intestinal dysfunction, resulting from the activation of donor T lymphocytes by host antigen-presenting cells, resulting in an immune-mediated inflammatory response. Recent scientific advances in the understanding of the pathogenesis involved in the development of acute GVHD and clinical investigation have provided more effective therapeutic strategies for acute GVHD. This review focuses on major scientific and clinical advances in the treatment of acute GVHD.

Prospective qualitative and quantitative non-invasive evaluation of intestinal acute GVHD by contrast-enhanced ultrasound sonography

Intestinal acute GVHD (I-aGVHD) is a life-threatening complication after allografting. Non-invasive bed-side procedures to evaluate extension and treatment response are still lacking. We hypothesized that, during I-aGVHD, contrast-enhanced ultrasound sonography (CEUS) could detect microcirculation changes (MVC) of the bowel wall (BW) and help to monitor treatment response. We prospectively employed CEUS in 83 consecutive patients. Of these, 14 patients with biopsy-proven intestinal GVHD (I-GVHD) were defined as the study group, whereas 16 patients with biopsy-proven stomach GVHD (U-GVHD) without intestinal symptoms, 6 normal volunteers and 4 patients with neutropenic enterocolitis were defined as the control group. All patients were evaluated with both standard ultrasonography (US) and CEUS at the onset of intestinal symptoms, during clinical follow-up and at flare of symptoms. Standard US revealed BW thickening of multiple intestinal segments, useful to determine the extension of GVHD. CEUS showed MVC, which correlated with GVHD activity, treatment response, and predicted flare of intestinal symptoms. US and CEUS findings were superimposable at diagnosis and in remission. CEUS was, however, more sensitive and specific to identify subclinical activity in patients with clinical relevant improvement. These findings were not observed in the control groups. CEUS is a non-invasive, easily reproducible bed-side tool useful to monitor I-aGVHD.

Combination cell therapy using mesenchymal stem cells and regulatory T-cells provides a synergistic immunomodulatory effect associated with reciprocal regulation of TH1/TH2 and th17/treg cells in a murine acute graft-versus-host disease model

Mesenchymal stem cells (MSCs) have been considered to be an ideal cellular source for graft-versus-host disease (GVHD) treatment due to their unique properties, including tissue repair and major histocompatibility complex (MHC)-unmatched immunosuppression. However, preclinical and clinical data have suggested that the immunomodulatory activity of MSCs is not as effective as previously expected. This study was performed to investigate whether the immunomodulatory capacity of MSCs could be enhanced by combination infusion of regulatory T (Treg) cells to prevent acute GVHD (aGVHD) following MHC-mismatched bone marrow transplantation (BMT). For GVHD induction, lethally irradiated BALB/c (H-2(d)) mice were transplanted with bone marrow cells (BMCs) and spleen cells of C57BL/6 (H-2(b)) mice. Recipients were injected with cultured recipient-derived MSCs, Treg cells, or MSCs plus Treg cells (BMT + day 0, 4). Systemic infusion of MSCs plus Treg cells improved clinicopathological manifestations and survival in the aGVHD model. Culture of MSCs plus Treg cells increased the population of Foxp3(+) Treg cells and suppressed alloreactive T-cell proliferation in vitro. These therapeutic effects were associated with more rapid expansion of donor-type CD4(+)CD25(+)Foxp3(+) Treg cells and CD4(+)IL-4(+) type 2 T-helper (Th2) cells in the early posttransplant period. Furthermore, MSCs plus Treg cells regulated CD4(+)IL-17(+) Th17 cells, as well as CD4(+)IFN-γ(+) Th1 cells. These data suggest that the combination therapy with MSCs plus Treg cells may have cooperative effects in enhancing the immunomodulatory activity of MSCs and Treg cells in aGVHD. This may lead to development of new therapeutic approaches to clinical allogeneic hematopoietic cell transplantation.

Current practice in diagnosis and treatment of acute graft-versus-host disease: results from a survey among German-Austrian-Swiss hematopoietic stem cell transplant centers

To assess current clinical practice in diagnosis and treatment of acute graft-versus-host disease (aGVHD), we performed a survey among German, Austrian, and Swiss allogeneic hematopoietic stem cell transplantation (allo-HSCT) centers. Thirty-four of 72 contacted centers (47%) completed both the diagnostic and therapeutic sections of the survey, representing 65% of allo-HSCT activity within the participating countries in 2011. Three pediatric centers answered as requested only the diagnostic part of the survey. In the presence of diarrhea and decreased oral intake after engraftment, only 4 centers (12%) do not perform any endoscopy before the start of immunosuppressive treatment. In case of a skin rash with the differential diagnosis of drug reaction, only 12 centers (35%) perform a skin biopsy up front, whereas 19 do so after failure of systemic steroids. In the presence of rapidly increasing cholestasis occurring without any other signs of aGVHD, 11 centers (32%) perform a liver biopsy up front and 14 only after failure of steroid treatment, whereas 9 centers do not perform a liver biopsy at all. Twenty centers (59%) use a percutaneous approach, 12 a transvenous approach, and 1 mini-laparoscopy for liver biopsies. First-line treatment of cutaneous aGVHD stage 1 consists of topical treatment alone in 17 of 31 responding centers (61%), whereas isolated cutaneous aGVHD stage III is treated with systemic steroids (prednisolone below 0.5 mg/kg/day n = 2, 0.5 to 1.0 mg/kg/day n = 10, above 1.0 to 2.5 mg/kg/day n = 19) without or with topical agents (steroids n = 10; calcineurin inhibitors n = 3). In gastrointestinal manifestations of aGVHD, 9 centers (29%) add topical to systemic steroids, and 3 consider topical steroids as the only treatment for mild gastrointestinal and cutaneous aGVHD. The choice of agent for second-line treatment as well as the sequence of administration are extremely heterogeneous, most likely due to a lack of convincing data published. Most frequently used are mycophenolate mofetil (n = 14) and extracorporeal photopheresis (n = 10). Our survey also demonstrates that clinicians chose salvage therapies for steroid-refractory aGVHD based on their centers' own clinical experience.

Concise review: acute graft-versus-host disease: immunobiology, prevention, and treatment

Graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplant (AHSCT) associated with significant morbidity and mortality. This review focuses on the pathophysiology, clinical features, prevention, and treatment of acute GVHD. Specifically, we explain how new discoveries in immunology have expanded our understanding of GVHD, in which tissue damage from chemotherapy or radiation results in cytokine release, which activates T cells, resulting in proliferation and differentiation, trafficking to target organs, and tissue destruction and inflammation. Insights into the mechanisms of this disease relate directly to the development of preventive strategies and therapies, such as immunosuppression, T-cell depletion, calcineurin inhibitors, CCR5 antagonists, gut decontamination, extracorporeal photopheresis, and more. We also discuss how GVHD affects the gut, liver, and skin, as well as diagnosis, grading, and scoring. We end by examining future directions of treatment, including new immunomodulators and biomarkers. Understanding the immunobiology of GVHD and developing effective preventions and treatments are critical to the continuing success of AHSCT.

Extracorporeal photopheresis in 62 patients with acute and chronic GVHD: results of treatment with the COBE Spectra System

In this retrospective analysis, 30 patients with acute GVHD (aGVHD) and 32 patients with chronic GVHD (cGVHD) treated with extracorporeal photopheresis (ECP) performed by the COBE Spectra System were evaluated. After 3 months of ECP treatment, a CR and PR were observed in 9 (30%) and 6 (20%) patients with aGVHD and in 2 (6%) and 12 (38%) patients with cGVHD. In 16 (53%) patients with aGVHD and 9 (28%) with cGVHD ECP treatment was already stopped after 3 months. One (3%) patient with aGVHD and 7 (22%) patients with cGVHD received new additional immunosuppressive therapy started during the first 3 months of ECP treatment and were classified as 'nonresponder' with regard to ECP. Of these patients a PR was achieved in one patient with aGVHD and in three patients with cGVHD. Steroids could be tapered by 50 in 83% of patients with aGVHD and in 29% of patients with cGVHD after 3 months of ECP treatment. Patients with aGVHD achieving a CR or PR showed a significant improved OS after allo-SCT (P=0.019). ECP is associated with significant response rates and successful reduction of steroids in patients with GVHD.

First- and second-line systemic treatment of acute graft-versus-host disease: recommendations of the American Society of Blood and Marrow Transplantation

Despite prophylaxis with immunosuppressive agents or a variety of other approaches, many patients suffer from acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation. Although consensus has emerged supporting the use of high-dose methylprednisolone or prednisone for initial treatment of aGVHD, practices differ among centers with respect to the initial glucocorticoid dose, the use of additional immunosuppressive agents, and the approach to withdrawal of treatment after initial improvement. Despite many studies, practices vary considerably with respect to the selection of agents for treatment of glucocorticoid-resistant or refractory GVHD. Investigators and clinicians have recognized the lack of progress and lamented the absence of an accepted standard of care for secondary treatment of aGVHD. The American Society of Blood and Marrow Transplantation has developed recommendations for treatment of aGVHD to be considered by care providers, based on a comprehensive and critical review of published reports. Because the literature provides little basis for a definitive guideline, this review also provides a framework for the interpretation of previous results and the design of future studies.

Clinical Results of Extracorporeal Photopheresis

Extracorporeal photopheresis (ECP) is a combination of leukapheresis and photodynamic therapy in which blood is treated with photoactivable drugs which are then activated with ultraviolet light and re-infused to the patient. It has been used successfully for more than 30 years in the treatment of erythrodermic cutaneous T-cell lymphoma (CTCL) and over 20 years for chronic graft-versus-host disease (GVHD). ECP has also shown promising results in the treatment of acute GVHD and other T-cell-mediated diseases, including systemic sclerosis, treatment and prevention of solid organ rejection, and more recently Crohn's disease. The use of ECP may allow a significant reduction or even discontinuation of corticosteroids and/or other immunosuppressants, thus leading to reduced long-term morbidity and mortality and improved overall survival. ECP is a well-tolerated therapy. No significant side effects have been reported during the last 30 years. It has been shown that ECP is not associated with an increased incidence of infections, malignancies, or recurrence of underlying malignant disease, neither during short-term nor during long-term therapy.

Extracorporeal photopheresis, a therapeutic option for cutaneous T-cell lymphoma and immunological diseases: state of the art

INTRODUCTION

Extracorporeal photopheresis (ECP) has been extensively used for the treatment of immune-mediated diseases for over 20 years and has a consistent and predictable safety profile with long-term use. Documenting the efficacy of ECP as therapeutic treatment has long been a matter of importance for physicians.

AREAS COVERED

The authors reviewed publications in this field with the goal of providing an overview of this therapeutic approach.

EXPERT OPINION

ECP is efficacious in a high percentage of those cutaneous T-cell lymphoma patients who have circulating malignant T cells in the context of a still-near-normal immune competence. From the side of graft-versus-host disease (GVHD), the use of ECP showed a clinical benefit in patients with steroid-refractory acute GVHD (aGVHD) and it is believed that ECP deserves to be evaluated as part of a combination strategy in first-line therapy of aGVHD. In chronic GHVD, the published data show that ECP can be effective in extensive and long-standing disease even when treatment is initiated at an advanced stage after conventional immunosuppressive and corticosteroid therapy has failed. ECP should be considered most beneficial for patients with predominantly mucocutaneous chronic GVHD. The fields of application of the procedure could be vast, and could also include autoimmune and metabolic diseases. The most important methodological issues which affect ECP evaluation is that the large majority of data about ECP result from single-arm observational series and the significant efficacy is mainly based on small and retrospective studies. ECP has never been proved to offer any survival advantage in a context of a randomized trial and the above-mentioned limitation also affects the accuracy of many biological modifications observed during ECP. Starting from these considerations, the need of a prospective randomized study becomes increasingly urgent.

Secondary treatment of acute graft-versus-host disease: a critical review

Management of steroid-resistant or steroid-refractory acute graft-versus-host disease (aGVHD) poses one of the most vexing and difficult problems faced by transplantation physicians. In the current study, we used 10 criteria to evaluate 67 reports describing secondary treatment of patients with aGVHD. The goal of this exercise was not only to provide a critical summary of the literature but also to offer suggestions that could improve future studies. Areas especially in need of improvement include the use of a consistent treatment regimen, the assessment of response at a consistent prespecified time point, consideration of concomitant treatment in assessing response, documentation that selection bias was minimized, and the use of methods that test a formal statistical hypothesis based on a contemporaneous or historical benchmark. Our results suggest that previous published reports collectively offer little guidance in discerning the most effective treatments for patients with steroid-resistant or steroid-refractory aGVHD. Adherence to the proposed criteria in future reports would enable meaningful comparisons across studies and thereby accelerate progress in evaluating new treatments for patients with aGVHD.

Clinical tolerance in allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) has been a curative therapeutic option for a wide range of immune hematologic malignant and non-malignant disorders including genetic diseases and inborn errors. Once in the host, allogeneic transplanted cells have not only to ensure myeloid repopulation and immunological reconstitution but also to acquire tolerance to host human leukocyte antigens via central or peripheral mechanisms. Peripheral tolerance after allogeneic HSCT depends on several regulatory mechanisms aimed at blocking alloimmune reactivity while preserving immune responses to pathogens and tumor antigens. Patients transplanted with HSCT represent an ideal model system in humans to identify and characterize the key cellular and molecular players underlying these mechanisms. The knowledge gained from these studies has allowed the development of novel therapeutic strategies aimed at inducing long-term peripheral tolerance, which can be applicable not only in allogeneic HSCT but also in autoimmune diseases and solid-organ transplantation. In the present review, we describe Type 1 regulatory T cells, initially discovered and characterized in chimeric patients transplanted with human leukocyte antigen-mismatched HSCT, and how their presence correlates to tolerance induction and maintenance. Furthermore, we summarize different cell therapy approaches with regulatory T cells, designed to facilitate tolerance induction, minimizing pharmaceutical interventions.

Extracorporeal photopheresis in addition to pentostatin in conditioning for canine hematopoietic cell transplantation: role in engraftment

Extracorporeal photopheresis (ECP) and the purine analog pentostatin exert potent immunomodulatory effects, but have not been evaluated for their ability to enhance engraftment of hematopoietic stem cells. We evaluated, in a canine model of dog leukocyte antigen (DLA)-identical hematopoietic cell transplantation (HCT), whether ECP in combination with pentostatin could enhance engraftment using a nonmyeloablative regimen consisting of 100 cGy TBI and postgrafting immunosuppression with mycophenolate mofetil and CYA. We have shown previously that with 100 cGy TBI alone as conditioning, all of the six dogs rejected their grafts 2-12 weeks after HCT. With the addition of pentostatin to 100 cGy TBI, 6 of 10 dogs rejected their graft. We now tested the additional use of ECP alone (n=2) or ECP and 3-6 doses of pentostatin (n=7) before 100 cGy TBI and HCT. Eight out of nine dogs rejected their grafts within 6-11 weeks after HCT. Compared with data without ECP, we failed to demonstrate a positive impact of the use of either ECP or pentostatin for prevention of rejection.

Guidelines on the use of therapeutic apheresis in clinical practice--evidence-based approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence-based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence-based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed.

Pathogenesis and management of graft-versus-host disease

Allogeneic hematopoietic cell transplantation (HCT) is an important therapeutic option for various malignant and nonmalignant conditions. As allogeneic HCT continues to increase, greater attention is given to improvements in supportive care, infectious prophylaxis, immunosuppressive medications, and DNA-based tissue typing. However, graft versus host disease (GVHD) remains the most frequent and serious complication following allogeneic HCT and limits the broader application of this important therapy. Recent advances in the understanding of the pathogenesis of GVHD have led to new approaches to its management, including using it to preserve the graft versus leukemia effect following allogeneic transplant. This article reviews the important elements in the complex immunologic interactions involving cytokine networks, chemokine gradients, and the direct mediators of cellular cytotoxicity that cause clinical GVHD, and discusses the risk factors and strategies for management of GVHD.

Pentostatin for treatment of steroid-refractory acute GVHD: a retrospective single-center analysis

Acute GVHD (aGVHD) remains a major cause of mortality in patients undergoing allo-SCT. In particular, the outcome of those patients who fail first-line therapy with glucocorticosteroids is poor. Preliminary reports suggested that the purine analogue pentostatin might be effective for treatment of steroid-refractory aGVHD. Here, we report on our single-center experience with pentostatin in this condition. From 2005 to 2008, a total of 24 consecutive patients, who had undergone first-line salvage treatment for steroid-refractory aGVHD of the gastrointestinal tract with pentostatin, were identified from 301 patients allografted during that period and retrospectively analyzed. Response to treatment, defined as CR or very good PR (VGPR), was observed in nine patients (38%), with a median time to response of 10 days. Although pentostatin was associated with only moderate myelosuppressive toxicity, if any, 2-year survival was only 17% with five of the nine responders dying from infection (four patients) or recurrent GVHD (one patient). We conclude that pentostatin is a moderately effective therapy for steroid-refractory aGVHD, showing response and outcome rates similar to other clinically used regimens.

[Four cases of photopheresis treatment for cutaneous lupus erythematosus refractory to standard therapy]

BACKGROUND

Photopheresis is a leucopheresis procedure in which cells are photoactivated by psoralen and then irradiated by ultraviolet A. We report four cases of women with refractory cutaneous lupus erythematosus (LE) who responded to this treatment.

PATIENTS AND METHODS

We treated one patient with subacute LE having a contraindication to antimalarials and to thalidomide and three patients with chronic LE (lupus panniculitis, lupus tumidus and disseminated discoid LE) refractory to treatment with hydroxychloroquine, chloroquine, thalidomide and dapsone, and also, in some cases, to oral and intravenous corticosteroids, methotrexate, colchicine, acitretine, sulfasalazine, mycophenolate mofetil and intravenous immunoglobulin. Treatment consisted of two 4-hour sessions fortnightly. Only antimalarials were continued during photopheresis.

RESULTS

Photopheresis had a positive effect on all four patients. We noticed complete remission in two patients and interruption of progression followed by partial remission in the other two after a mean delay of two to three months of treatment. All treatments other than antimalarials were stopped.

DISCUSSION

Photopheresis appears to be an effective treatment option in patients with cutaneous LE. Due to its high cost, it should nevertheless remain an exceptional therapeutic option restricted to patients with cutaneous LE resistant to standard therapy.

Management of acute graft-versus-host disease in children

Acute graft-versus-host disease (aGVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT) in children. Although 30% to 50% of children respond to corticosteroids as initial therapy, the optimal initial or second-line therapies have not yet been determined. Newer approaches with combination therapy, novel agents, monoclonal antibodies, and/or cellular therapies show some promise but require prospective well-designed trials that include children to establish their efficacy. This article reviews the clinical presentation, treatment, and practical management guidelines for children with aGVHD.

Acute graft-versus-host disease: new treatment strategies

PURPOSE OF REVIEW

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT), despite improvements in our understanding of its pathophysiology as well as the generation of new monoclonal antibodies, immunomodulatory chemotherapy, cellular therapeutics and supportive care. Herein, we review therapies that have proven effective as well as newer agents that have recently improved GVHD response rates and survival following HCT.

RECENT FINDINGS

Novel approaches to prevent or treat GVHD are often based on evidence from experimental models. Our understanding of the pathophysiology of GVHD may lead to the development of innovative strategies that target both soluble and cellular effectors. Among such agents are sirolimus, anti-tumor necrosis factor antibodies, anti-LFA-3-IgG fusion protein, extracorporeal photopheresis, mesenchymal stem cells and regulatory T cells.

SUMMARY

Obstacles to the improvement of HCT include the tight linkage between GVHD toxicity and the beneficial graft-versus-leukemia (GVL) effect, as well as the impairment of immune reconstitution by immunomodulatory drugs leading to life-threatening infections. The design of newer phase I/II clinical trials are underway. Future therapies are likely to include modulation of cell types that play key roles in the GVH process, including regulatory T cells, dendritic cells, natural killer T cells and B cells.

Recent advances in hematopoietic stem cell transplantation and perspectives of RNAi applications

In adults, the bone marrow compartment contains hematopoietic stem cells (HSCs) which can differentiate into progenitors with more restricted lineage potential and generate all cellular elements of the blood. HSCs for stem cell transplantation can be obtained by bone marrow collection, mobilization into peripheral blood followed by apheresis, or use of stem cells from cord blood. Currently, hematopoietic stem cell transplantation (SCT) is used to treat patients with various hematological diseases. Although substantial progress has been made, a number of challenges can limit the efficacy of HSC transplantation, including the occurrence of graft-versus-host disease (GvHD) in allogeneic stem cell transplantation (ASCT), the susceptibility of patients to opportunistic infections and relapse of malignancies after SCT. Recent studies indicate that small interfering RNAs (siRNAs) can specifically and efficiently interfere with the expression of oncogenic genes. Therefore, the possibility of interfering with the expression of these proteins in hematopoietic cells may offer a new option to correct cell differentiation and function. In addition to the generation of T cells restricted by nonself MHC as reviewed by Stauss and colleagues in 1999, the modulation of NK cell receptor expression and T-cell activation is a new strategy that could limit GvHD. This chapter reviews the recent advances in ASCT and discusses the potential application of RNAi in hematopoietic cells.

Extracorporeal photo-apheresis for the treatment of steroid-resistant graft versus host disease

Acute and chronic graft versus host disease are frequent and potentially severe complications of allogeneic hematopoietic stem cell transplantation and are among the leading causes of non-relapse transplant-related mortality. For patients with steroid refractory disease, prognosis is particularly poor and although a variety of treatment options are available, responses are commonly transient and the side effects often intolerable. Since it was first introduced for the treatment of cutaneous T-cell lymphoma, extracorporeal photo-apheresis has been utilized as an immunomodulatory therapy for certain autoimmune diseases and solid organ transplant rejection. Recently, extracorporeal photo-apheresis has become a promising alternative for patients with graft versus host disease with disabling or potentially lethal complications. Here we review the experience of extracorporeal photo-apheresis for the treatment of steroid refractory acute and chronic graft versus host disease based on the current literature.

Emerging drugs for acute graft-versus-host disease

The number of allogeneic hematopoietic cell transplantations (HCT) continues to increase. More than 15,000 allogeneic transplantations are performed annually. The graft-versus-leukemia/tumor effect during allogeneic HCT effectively eradicates many hematological malignancies. The development of novel strategies that use donor leukocyte infusions, nonmyeloablative conditioning and umbilical cord blood transplantation have helped expand the indications for allogeneic HCT over the past several years, especially among older patients. Yet the major complication of allogeneic HCT, graft-versus-host disease, remains lethal and limits wider application of allogeneic HCT. In this article, we review current practice and recent advances made in prevention and treatment of graft-versus-host disease.