Photopheresis for the prevention of rejection in cardiac transplantation. Photopheresis Transplantation Study Group

Current Expectations for Cardiac Transplantation in Patients With Congenital Heart Disease

Congenital heart disease accounts for 40% of pediatric heart transplants and presents unique challenges to the transplant team. Suitability for transplantation is defined in part by degree of sensitization, pulmonary vascular resistance, and hepatic reserves. The incremental transplant risk for patients with congenital heart disease occurs within the first 3 months, after which survival is equivalent to transplantation for cardiomyopathy. Single ventricle with prior palliation, and especially the failing Fontan, carry the highest risk for transplantation and are least amenable to bridging with mechanical circulatory support. More effective bridging to transplant with mechanical circulatory support will require improvements in the adverse event profile of available pumps and the introduction of miniaturized continuous flow technology. The major barriers to routine long-term survival are chronic allograft failure and allograft vasculopathy. Despite these many challenges, continuing improvements in the care of pediatric heart transplant patients have pushed the median posttransplant survival past 15 years for children and to 20 years for infants.

Extracorporeal Photopheresis in the Treatment of Persistent Rejection in a Pediatric Lung Transplant Recipient

Lung transplantation is an accepted therapy for children with end-stage lung disease. One-year lung transplant survival rates of 86% have been reported by the United Network for Organ Sharing. Allograft rejection is a common cause of death following transplantation. Extracorporeal photopheresis is a novel therapy used to treat solid-organ rejection; this therapy involves separating the leukocyte-rich fraction from whole blood, treating with psoralen and ultraviolet light A exposure. The objective of therapy is to reverse progressive and persistent rejection. Working collaboratively with an institution that offers extracorporeal photopheresis may provide an alternative or additional therapy in the management of ongoing rejection following solid-organ transplantation.

Current diagnostic and treatment strategies for cardiac allograft vasculopathy

Heart transplantation remains the most durable treatment for end-stage heart disease that is not amenable to coronary revascularization or anti-arrhythmic therapies. Cardiac allograft vasculopathy (CAV) remains one of the main contributors to morbidity and mortality post heart transplant. Nonimmune and immune factors that influence CAV can be modified after a heart transplant. Given the potential silent nature of CAV in the denervated heart, early diagnosis of CAV is critical. Diagnosis and treatment of CAV remain key areas of investigation to improve patient care and quality of life post heart transplant. While repeat heart transplantation is an option in the treatment of significant CAV, outcomes following retransplantation are inferior to outcomes following first heart transplant. Repeat heart transplantation is limited to a select group of patients after index heart transplant.

Extracorporeal photopheresis as an immunomodulatory agent: Haematocrit-dependent effects on natural killer cells

The GvHD is a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Extracorporeal photopheresis (ECP) represents an alternative therapeutic strategy to immunosuppressive therapy. Although ECP is used since 1990s, the mechanism of action has not yet been completely clarified. We analyzed cells collected from 20 ECP procedures of 4 patients affected by chronic GvHD and, for comparison, Peripheral Blood Mononuclear Cells (PBMCs) of 10 healthy donors undergoing from same type of photochemiotherapy, evaluating by flow cytometry, the effects before and after photoactivation with 8-MOP. The analysis showed a significant increase in cell death after ECP in particular in CD4 T lymphocytes as described in literature correlated with haematocrit value. Most interesting data emerge from the analysis of cytotoxic activity of NK cells, using flow cytometry analysis of surface expression of CD107a in the presence of target cells (K562). In all analyzed samples it was possible to document a statistically significant reduction of the cytotoxic activity of NK cells after photoactivation. The decrease of the cytotoxic activity was related to hematocrit value of leukoapheresis: in fact, lower HCT values were associated with a more marked reduction of cytotoxic activity. The study confirms literature data about the increase of cellular mortality induce by ECP. Furthermore, for the first time it is demonstrated that the ECP exerts a marked and significant inhibitory effect on the cytotoxic activity of NK cells. Our study suggests that lower values of hematocrit are associated with better treatment outcome.

Induction of anti-tumor CD8 T cell responses by experimental ECP-induced human dendritic antigen presenting cells

Extracorporeal photochemotherapy (ECP), or photopheresis, is distinguished by the specificity of the clinically potent immunologic reactions it initiates or regulates. The selectivity of ECP-induced immunoprotection for the malignant clone in cutaneous T cell lymphoma (CTCL), and for the pathogenic clones in allograft rejection and graft-versus-host disease (GVHD), has suggested a central mechanistic role for dendritic antigen presenting cells (DC). Discovery of ECP's induction of monocyte-derived DC, via monocyte signaling by ECP-plate activated platelets, and the absolute dependency of experimental ECP on such induced DC, supports that premise. Herein, we show that ECP-induced DC are capable of stimulating CD8 T cell responses to tumor antigens with which they are loaded. They internalize an antigen-specific melanoma-associated protein then present it onto a class I major histocompatibility, which then stimulates expansion of anti-tumor CD8 T cell populations. We conclude that ECP-induced DC prominently contribute to its initiation of anti-tumor immunity and raise the possibility that the therapy may be applicable to the immunotherapeutic management of a broader spectrum of cancers.

Concise Review: Mechanisms Behind Apoptotic Cell-Based Therapies Against Transplant Rejection and Graft versus Host Disease

The main limitations to the success of transplantation are the antigraft response developed by the recipient immune system, and the adverse side effects of chronic immunosuppression. Graft-versus-host disease (GVHD) triggered by donor-derived T lymphocytes against the recipient tissues is another serious obstacle in the field of hematopoietic stem cell transplantation. Several laboratories have tested the possibility of promoting antigen (Ag)-specific tolerance for therapy of graft rejection, GVHD, and autoimmune disorders, by developing methodologies that mimic the mechanisms by which the immune system maintains peripheral tolerance in the steady state. It has been long recognized that the silent clearance of cells undergoing apoptosis exerts potent immune-regulatory effects and provides apoptotic cell-derived Ags to those Ag-presenting cells (APCs) that internalize them, in particular macrophages and dendritic cells. Therefore, in situ-targeting of recipient APCs by systemic administration of leukocytes in early apoptosis and bearing donor Ags represents a relatively simple approach to control the antidonor response against allografts. Here, we review the mechanisms by which apoptotic cells are silently cleared by phagocytes, and how such phenomenon leads to down-regulation of the innate and adaptive immunity. We discuss the evolution of apoptotic cell-based therapies from murine models of organ/tissue transplantation and GVHD, to clinical trials. We make emphasis on potential limitations and areas of concern of apoptotic cell-based therapies, and on how other immune-suppressive therapies used in the clinics or tested experimentally likely also function through the silent clearance of apoptotic cells by the immune system. Stem Cells 2016;34:1142-1150.

Extracorporeal photopheresis after heart transplantation

The addition of extracorporeal photopheresis (ECP) to a standard immunosuppressive drug therapy after heart transplantation in clinical studies has shown to be beneficial, for example, by reducing acute rejection, allograft vasculopathy or CMV infection. However, the protocols varied considerably, have a predetermined finite number of ECP treatments and adjuvant immunosuppressive regimens used in combination with ECP have differed significantly. Furthermore, there are scarce data to guide which patients should be treated with ECP and when or who would benefit further if ECP were to be continued long term to increase the safety by reducing immunosuppressive drug toxicities without losing efficacy. The knowledge of the tolerance-inducing effects of ECP-like upregulation of regulatory T cells and of dendritic cells may allow to develop a strategy to monitor immunomodulation effects of ECP to further identify ECP responders, the optimal individual ECP schedule and whether ECP therapy can replace or reduce immunosuppressive drug therapy.

Novel immunosuppressive strategies for composite tissue allografts

PURPOSE OF REVIEW

Vascularized composite tissue allografts (CTAs) provide excellent restorative options for patients with limb loss and other deformities. Acute rejection remains common with CTA and immunosuppression is used in an attempt to prevent rejection. This has created ethical debates regarding the use of intensive immunosuppression for a nonlife-saving procedure. This highlights the need for newer immunosuppressive strategies for CTA, which are described in this review.

RECENT FINDINGS

Recent studies have looked into immunomodulation and tolerance to decrease toxicity of immunosuppression. Both strategies have had some success but have their own limitations. Although immunomodulation and decrease in immunosuppression decreases toxicity, it has been associated with higher rates of rejection. Induction of tolerance has achieved some initial success, but the initial conditioning regimens are associated with significant morbidity.

SUMMARY

Although recent advancements have been made in the immunosuppressive strategies in CTA, the ideal immunosuppression strategy with low toxicity and infection risk but with the ability to prevent acute and chronic rejection is yet to be discovered.

A concise review on extracorporeal photochemotherapy: Where we began and where we are now and where are we going!

Currently, more than 1080 peer-reviewed papers are displayed on PubMed when initiating a search for therapeutic indications and mechanisms of action of extracorporeal photochemotherapy (ECP). This concise review focuses mainly on some prevalent and traditional treatment-resistant disorders with an emphasis on immunologic complications emerging from stem cell and solid organ transplantation.

Extracorporeal photopheresis in heart transplant rejection

Up to 25% of heart transplant recipients develop rejection requiring intervention. While the majority respond to augmentation of immunomodulatory drug therapy, a subset of patients will remain refractory. Extracorporeal photopheresis (ECP) appears particularly useful in the management of select heart transplant recipients at risk of rejection, with recurrent rejection, or rejection associated with hemodynamic compromise. This chapter summarizes the current clinical experience of ECP in heart transplantation. ECP appears to favorably affect both the cellular and humoral arms of the immune response to the allograft and promote a tolerogenic profile. These immunomodulatory effects also appear to decrease development of cardiac allograft vasculopathy. ECP is generally well tolerated with few adverse effects and low infection risk.

Extracorporeal photopheresis as a therapy for autoimmune diseases

Systemic autoimmune diseases (AID) have multiorgan, heterogeneous clinical presentations and are characterized by dysregulation of the immune system, immunodeficiency, irreversible organ damage and increased morbidity and mortality. Preventing or decreasing flares of AID correlate with durable disease control, significant reduction of inflammation and prevention of disability or therapy-related toxicity. There is an urgent need for better treatment of severe, therapy-refractory AID. Extracorporeal photopheresis (ECP) is a cell-based immunomodulatory treatment which has been extensively used in variety of autoimmune disorders for the last two decades. ECP treatment is FDA approved for the treatment of cutaneous T-cell lymphoma (CTCL) with particularly promising results seen in graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HCT). Prolonged therapy is safe, well tolerated and allows reduction of systemic immunosuppression in therapy-refractory patients. Both clinical and experimental evidence suggest that ECP mechanism of action is characterized by apoptosis and phagocytosis of activated cells by antigen-presenting cells (APC), secretion of anti-inflammatory cytokines and stimulation of regulatory T cells (Tregs). The focus of this paper is to review the current evidence of ECP use in the treatment of AID. Here, we summarize the experience of nine major AID from 65 published reports. The key findings demonstrate substantial evidence of ECP feasibility, safety and in some AID also promising efficacy. However, the role of ECP in AID therapy is not established as most published studies are retrospective with limited number of patients and the trials are small or poorly standardized. The available data support future investigations of ECP as a therapeutic modality for the treatment of AID in well-designed prospective clinical studies. J

National Institutes of Health State of the Science Symposium in Therapeutic Apheresis: scientific opportunities in extracorporeal photopheresis

The clinical use of extracorporeal photopheresis (ECP) for accepted indications such as graft-versus-host disease, transplant rejection, and cutaneous T-cell lymphoma continues to increase. Expanded applications for ECP, such as the treatment of select autoimmune diseases, are being explored. Extracorporeal photopheresis's capacity to both immunotolerize in the autoreactive setting, while immunizing against a lymphoma is unusual and suggestive of a unique mechanism. It is likely that ECP's induction of dendritic cells is key to its efficacy in both of these settings, but exactly how ECP impacts other immune components and their interactions is not fully understood. Further basic science research is necessary to elucidate how these dissimilar cellular activities are functionally integrated. On the clinical side, collaborative multicenter trials designed to recognize the principal variables controlling therapeutic responses and improve prognostic indicators may enable tailoring devices, treatment schedules, and doses to the needs of the individual patients or diseases. This review describes our current understanding of how ECP influences the immune system, reviews the existing clinical applications of ECP, and explores areas for future basic science and clinical research as presented at the National Institutes of Health State of the Science Symposium in Therapeutic Apheresis in November 2012.

Immunosuppression following heart transplantation: prospects and challenges

Immunosuppression after heart transplantation has significantly reduced the incidence of cellular rejection and improved patient outcomes with the routine use of calcineurin inhibitors. Antimetabolites and proliferation signal inhibitors add to the improvement in patient outcomes, particularly with respect to the reduced burden of cardiac allograft vasculopathy. Patients with antibody sensitization are potentially at higher risk of postoperative complications. Sensitized patients are undergoing heart transplantation with increased frequency, in part due to the emergence of ventricular assist device use as a bridge to heart transplantation. Despite improvements in immunosuppressive therapies, many challenges face physicians and patients, which will further refine and improve care of the post-heart transplant patient.

Lung transplant immunosuppression - time for a new approach?

Outcomes after lung transplantation remain worse compared to other solid organ transplants, which is in large part due to high rates of graft rejection. Despite emerging data that immune responses to lungs differ from other organs, immunosuppression for lung transplant recipients is still based on strategies established for recipients of other grafts. There exists an urgent need to develop immunosuppressive strategies for lung transplant recipients that take the unique immunological features of this organ into account.

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: technique, established and novel indications

Extracorporeal photopheresis (ECP) has had a major impact in the treatment of various conditions in the past 25 years. Although it was initially developed for the treatment of patients with resistant cutaneous T cell lymphoma (CTCL), this therapy was later used to treat recipients of solid organs and stem cell transplants with rejection or graft-versus-host disease (GVHD), respectively. A significant number of patients with CTCL can achieve long term remission with ECP therapy. Those patients with heart or lung transplants may experience fewer or shorter rejection episodes following ECP. Furthermore, patients that respond to ECP can generally reduce the dose of immunosuppression medication, thus minimizing the morbidity caused by drugs such as corticosteroids and calcineurin inhibitors. While the exact mechanism of action of ECP is not well-understood, evidence suggests that reinfusion of the patient's apoptotic white blood cells, the ultimate product of ECP, promotes immunomodulatory events that are beneficial in patients with CTCL, transplant rejection, GVHD, and possibly other inflammatory conditions.

Immunological monitoring of extracorporeal photopheresis after heart transplantation

Extracorporeal photopheresis (ECP) has been used as a prophylactic and therapeutic option to avoid and treat rejection after heart transplantation (HTx). Tolerance-inducing effects of ECP such as up-regulation of regulatory T cells (T(regs)) are known, but specific effects of ECP on regulatory T cell (T(reg)) subsets and dendritic cells (DCs) are lacking. We analysed different subsets of T(regs) and DCs as well as the immune balance status during ECP treatment after HTx. Blood samples were collected from HTx patients treated with ECP for prophylaxis (n = 9) or from patients with histologically proven acute cellular rejection (ACR) of grade ≥ 1B (n = 9), as well as from control HTx patients without ECP (HTxC; n = 7). Subsets of T(regs) and DCs as well as different cytokine levels were analysed. Almost 80% of the HTx patients showed an effect to ECP treatment with an increase of T(regs) and plasmacytoid DCs (pDCs). The percentage of pDCs before ECP treatment was significantly higher in patients with no ECP effect (26·3% ± 5·6%) compared to patients who showed an effect to ECP (9·8% ± 10·2%; P = 0·011). Analysis of functional subsets of CD4⁺CD25(high)CD127(low) T(regs) showed that CD62L-, CD120b- and CD147-positive T(regs) did not differ between the groups. CD39-positive T(regs) increased during ECP treatment compared to HTxC. ECP-treated patients showed higher levels for T helper type 1 (Th1), Th2 and Th17 cytokines. Cytokine levels were higher in HTx patients with rejection before ECP treatment compared to patients with prophylactic ECP treatment. We recommend a monitoring strategy that includes the quantification and analysis of T(regs), pDCs and the immune balance status before and up to 12 months after starting ECP.

ECP and solid organ transplantation

Since its introduction in photomedicine in 1983 ECP (extracorporeal photopheresis) has over the past decades been established as a safe and effective treatment approach for the palliative management of patients with cutaneous T-cell lymphoma, the Sezary syndrome variant in particular. Subsequently its effectiveness has been well documented in a number of additional T-cell-mediated diseases, particularly in the treatment and prevention of acute and chronic graft-vs. -host disease. More recently, ECP has been successfully used to treat acute heart allograft rejection and chronic allograft dysfunction after lung transplantation without increasing infectious complications. As recently documented ECP was also used as a part of CNI (calcineurin inhibitors) sparing or staggering protocols. For this group of patients it is proposed that its efficacy may be partly attributed through direct induction of lymphocyte apoptosis (Tambur et al., 2000) [1] and subsequent production of regulatory T cells (Treg) (Lamioni et al., 2007) [2,3] without causing general immunosuppression. However, the exact indications for use of ECP within this framework are not yet finalized.

Pediatric therapeutic apheresis: rationale and indications for plasmapheresis, cytapheresis, extracorporeal photopheresis, and LDL apheresis

Apheresis refers to the removal of a component of the blood and is performed using a group of medical technologies in which peripheral blood is processed by an instrument that separates the various components. The selected component is isolated while the remainder is returned to the patient. The rationale behind therapeutic apheresis is to remove the pathogenic components from the circulation. Apheresis is also used for peripheral hematopoietic progenitor cell collection. The procedure can be safely performed in most children with modifications to account for smaller pediatric blood volumes.

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.

Mechanistic insights into extracorporeal photochemotherapy: efficient induction of monocyte-to-dendritic cell maturation

Extracorporeal photochemotherapy (ECP) is a widely used immunotherapy for cutaneous T cell lymphoma, as well as immunomodulation of graft-versus-host disease (GVHD) and transplanted organ rejection. ECP's mechanism encompasses large-scale physiologic platelet induction of dendritic cells (DCs). The normal bidirectional immunologic talents of DCs likely contribute heavily to ECP's capacity to immunize against tumor antigens, while also suppressing transplant immunopathology. Our understanding of how ECP physiologically induces monocyte-to-DC maturation can enhance the treatment's potency, potentially broaden its use to other cancers and autoimmune disorders and tailor its application to individual patients' diseases. ECP's next decade is filled with promise.

Bronchiolitis obliterans syndrome: the Achilles' heel of lung transplantation

Lung transplantation is a therapeutic option for patients with end-stage pulmonary disorders. Unfortunately, chronic lung allograft dysfunction (CLAD), most commonly manifest as bronchiolitis obliterans syndrome (BOS), continues to be highly prevalent and is the major limitation to long-term survival. The pathogenesis of BOS is complex and involves alloimmune and nonalloimmune pathways. Clinically, BOS manifests as airway obstruction and dyspnea that are classically progressive and ultimately fatal; however, the course is highly variable, and distinguishable phenotypes may exist. There are few controlled studies assessing treatment efficacy, but only a minority of patients respond to current treatment modalities. Ultimately, preventive strategies may prove more effective at prolonging survival after lung transplantation, but their remains considerable debate and little data regarding the best strategies to prevent BOS. A better understanding of the risk factors and their relationship to the pathological mechanisms of chronic lung allograft rejection should lead to better pharmacological targets to prevent or treat this syndrome.

Vascularized composite tissue allotransplantation--state of the art

Vascularized composite tissue allotransplantation is a viable treatment option for injuries and defects that involve multiple layers of functional tissue. In the past 15 yr, more than 150 vascularized composite allotransplantation (VCA) surgeries have been reported for various anatomic locations including - but not limited to - trachea, larynx, abdominal wall, face, and upper and lower extremities. VCA can achieve a level of esthetic and functional restoration that is currently unattainable using conventional reconstructive techniques. Although the risks of lifelong immunosuppression continue to be an important factor when evaluating the benefits of VCA, reported short- and long-term outcomes have been excellent, thus far. Acute rejections are common in the early post-operative period, and immunosuppression-related side effects have been manageable. A multidisciplinary approach to the management of VCA has proven successful. Reports of long-term graft losses have been rare, while several factors may play a role in the pathophysiology of chronic graft deterioration in VCA. Alternative approaches to immunosuppression such as cellular therapies and immunomodulation hold promise, although their role is so far not defined. Experimental protocols for VCA are currently being explored. Moving forward, it will be exciting to see whether VCA-specific aspects of allorecognition and immune responses will be able to help facilitate tolerance induction.

A prospective interventional study on the use of extracorporeal photopheresis in patients with bronchiolitis obliterans syndrome after lung transplantation

BACKGROUND

The aim of this prospective study was to evaluate the efficacy and safety of extracorporeal photopheresis (ECP) in patients with bronchiolitis obliterans syndrome (BOS) after lung transplantation and to identify factors predicting treatment response.

METHODS

The study was performed at a single center and consisted of a cohort of 1,012 lung transplant recipients (November 1989-June 2010). A total of 194 patients developed BOS after a mean of 1,293 ± 1,008 days (range, 99-4,949 days) and received established treatment, and 51 patients received additional ECP.

RESULTS

Thirty-one (61%) of the ECP-treated patients responded to the therapy and showed sustained stabilization (forced expiratory volume in 1 second range, -5% to 5% vs baseline at start of ECP) of lung function over 6 months. Responders to ECP showed significantly greater survival and less need for retransplantation (p = 0.001) than non-responders. Factors associated with an inferior treatment response were cystic fibrosis as underlying lung disease and a longer time between transplantation and development of BOS. No side effects were observed after ECP. Compared with BOS patients not treated with ECP, the ECP responders showed an improved graft survival (p = 0.05).

CONCLUSIONS

These results confirm and suggest that early use of ECP could be an effective adjunct treatment for patients who develop BOS after lung transplantation.

New issues in heart transplantation for heart failure

OPINION STATEMENT

Heart transplantation is the preferred therapy for patients with end-stage heart failure with refractory symptoms despite optimal medical and device therapy. The major impediment to survival is rejection and infection in the short term and cardiac allograft vasculopathy and malignancy in the long term. Current therapies are focused on the prevention and treatment of rejection and limiting the long-term problems of cardiac allograft vasculopathy and malignancy. Advances in monitoring assays now allow better assessment of rejection and the level of immune response. This will allow clinicians, in the future, to tailor current therapies to the needs of individual heart transplant recipients to maximize benefit and minimize toxicity.

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.

Nonpharmacologic treatment of chronic graft-versus-host disease in children and adolescents

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for many children with life-threatening diseases. One of the most significant long-term complications of transplantation is chronic graft-versus-host disease (cGVHD). Although the rates of cGVHD after HSCT are lower in the pediatric population than in adults, cGVHD remains a significant cause of morbidity and mortality. Medicines used to prevent and treat cGVHD remain unsatisfactory, with protracted use of immune suppression necessary and high rates of first-line treatment failure. Efforts to improve salvage treatment are urgently required. Nonpharmacologic strategies attempt to modulate the cellular inflammation response and possibly allow reduction or cessation of immunosuppressive drugs. Mesenchymal stromal cells (MSC) have been shown in vitro to mediate a wide variety of immune responses. MSC have been used in the prophylaxis of acute GVHD (aGVHD) and for the treatment of established steroid refractory aGVHD and, more recently, in the management of cGVHD. Extracorporeal photochemotherapy (ECP) has shown promising efficacy in graft-versus-host disease, and may allow a significant reduction in the use of systemic steroids and other immunosuppressants, reducing long-term morbidity and mortality. The accumulated experience shows ECP to be well tolerated, with no clinically significant side effects.

Therapeutic apheresis for renal disorders

This review summarizes the clinical evidence and practical details for the use of plasmapheresis and other apheresis modalities for each indication in nephrology. Updated information on the molecular biology and immunology of each renal disease is discussed in relation to the rationale for apheresis therapy and its place amid other available treatments. Autoantibody-mediated diseases, such as anti-GBM (anti-glomerular basement membrane) glomerulonephritis (GN), ANCA (antineutrophil cytoplasmic antibody)-related GN and the antibody-mediated type of TTP (thrombotic thrombocytopenic purpura), and alloantibody-mediated diseases such as kidney transplant sensitization and humoral rejection, can be treated by various plasmapheresis methods. These include standard plasmapheresis with a replacement volume, or plasmapheresis with online plasma purification using adsorption columns or secondary filtration. However, it should be noted that the pathogenic molecules implicated in FSGS (focal segmental glomerulosclerosis), myeloma cast nephropathy, and perhaps other diseases are too small to be removed by most online purification methods. A great majority of controlled trials and series on which evidence-based treatment recommendations are made were performed using centrifugal plasmapheresis; it is presumed that membrane-separation plasmapheresis is equally efficacious. For some rarer diseases, such as MPGN (membranoproliferative GN) type 2 with factor H abnormalities or C3Nef (C3 nephritic factor) autoantibodies, there are only a few case reports, but enough scientific understanding to warrant a trial of plasmapheresis in severe cases. Photopheresis, which is effective for cell-mediated rejection in heart and lung transplantation, has not yet found a place in the routine treatment of kidney transplant rejection.