Extracorporeal Photopheresis as an Antirejection Prophylaxis in Kidney Transplant Recipients: Preliminary Results

The role of efferocytosis and transplant rejection: Strategies in promoting transplantation tolerance using apoptotic cell therapy and/or synthetic particles

Recently, efforts have been made to recognize the precise reason(s) for transplant failure and the process of rejection utilizing the molecular signature. Most transplant recipients do not appreciate the unknown length of survival of allogeneic grafts with the existing standard of care. Two noteworthy immunological pathways occur during allogeneic transplant rejection. A nonspecific innate immune response predominates in the early stages of the immune reaction, and allogeneic antigens initiate a donor-specific adaptive reaction. Though the adaptive response is the major cause of allograft rejection, earlier pro-inflammatory responses that are part of the innate immune response are also regarded as significant in graft loss. The onset of the innate and adaptive immune response causes chronic and acute transplant rejection. Currently employed immunosuppressive medications have shown little or no influence on chronic rejection and, as a result, on overall long-term transplant survival. Furthermore, long-term pharmaceutical immunosuppression is associated with side effects, toxicity, and an increased risk of developing diseases, both infectious and metabolic. As a result, there is a need for the development of innovative donor-specific immunosuppressive medications to regulate the allorecognition pathways that induce graft loss and to reduce the side effects of immunosuppression. Efferocytosis is an immunomodulatory mechanism with fast and efficient clearance of apoptotic cells (ACs). As such, AC therapy strategies have been suggested to limit transplant-related sequelae. Efferocytosis-based medicines/treatments can also decrease the use of immunosuppressive drugs and have no detrimental side effects. Thus, this review aims to investigate the impact of efferocytosis on transplant rejection/tolerance and identify approaches using AC clearance to increase transplant viability.

Mode of action, indications and recommendations on extracorporeal photopheresis (ECP)

Extracorporeal photopheresis (ECP) has gained importance in the treatment of several diseases. Initially introduced as a new therapeutic modality for the treatment of patients with cutaneous T-cell lymphoma, the indications for the use of ECP have expanded to include hematology and transplantation immunology. Extracorporeal photopheresis has found its place in the treatment plan of cutaneous T-cell lymphoma, systemic sclerosis, graft-versus-host disease, organ transplantation such as heart and lung, sometimes as first-line therapy and very often in combination with various systemic immunosuppressive therapies. The procedure basically consists of three steps: leukapheresis, photoactivation and reinfusion. The following article presents possible theories about the mechanism of action, which is not yet fully understood, and discusses the five most common indications for ECP treatment with corresponding therapy recommendations.

Wirkweise, Indikationen und Therapieempfehlungen der extrakorporalen Photopherese (ECP)

Die extrakorporale Photopherese (ECP) hat in jüngster Zeit bei der Behandlung verschiedener Krankheiten an Bedeutung gewonnen. Ursprünglich als neue Therapie zur Behandlung von Patienten mit kutanem T‐Zell‐Lymphom vorgestellt, hat sich der Indikationsbereich für die ECP auf Hämatologie und Transplantationsimmunologie erweitert. Die ECP hat ihren festen Platz im Therapieplan bei kutanen T‐Zell‐Lymphomen, systemischer Sklerose, Graft‐versus‐Host‐Erkrankung, Organtransplantationen wie Herz und Lunge, teilweise als Erstlinientherapie und sehr häufig in Kombination mit verschiedenen systemischen immunsuppressiven Therapien. Das Verfahren besteht im Wesentlichen aus drei Schritten: Leukapherese, Photoaktivierung und Reinfusion. Im folgenden Artikel werden die noch nicht vollständig verstandenen Wirkmechanismen dargestellt, die fünf häufigsten Indikationen für die Behandlung mit ECP diskutiert und Therapieempfehlungen für die jeweilige Indikation gegeben.

Novel insights in the clinical management of hyperimmune patients before and after transplantation

Despite improvements in anti-Human Leucocyte Antigens antibody detection, identification, and characterization offer a better in peri-operative management techniques, antibodies remain a serious cause of morbidity and mortality for patients both before and after organ transplantation. Hyperimmune patients are disadvantaged by having to wait longer to receive an organ from a suitably matched donor. They could benefit from desensitization protocols in both pre- and post-transplantation period. Clinical studies are underway to highlight which best desensitization strategies could be assure the best outcome in both heart and kidney transplantation. Although most clinical evidence about desensitization strategies by using anti-CD20 monoclonal antibodies, proteasome inhibitors, anti-CD38 monoclonal antibodies, interleukin-6 blockade, cysteine protease and complement inhibitors, comes from kidney transplantation studies, many of the debated novel concepts can be easily applied to desensitization also in heart transplantation. Here, we discuss the candidates and recipients' management by using most common standard of care and novel therapeutics, desensitization endpoints, and strategies for future studies.

Pre-transplant infusion of donor leukocytes treated with extracorporeal photochemotherapy induces immune hypo-responsiveness and long-term allograft survival in murine models

Recipients of solid organ transplantation (SOT) rely on life-long immunosuppression (IS), which is associated with significant side effects. Extracorporeal photochemotherapy (ECP) is a safe, existing cellular therapy used to treat transplant rejection by modulating the recipient’s own blood cells. We sought to induce donor-specific hypo-responsiveness of SOT recipients by infusing ECP-treated donor leukocytes prior to transplant. To this end, we utilized major histocompatibility complex mismatched rodent models of allogeneic cardiac, liver, and kidney transplantation to test this novel strategy. Leukocytes isolated from donor-matched spleens for ECP treatment (ECP-DL) were infused into transplant recipients seven days prior to SOT. Pre-transplant infusion of ECP-DL without additional IS was associated with prolonged graft survival in all models. This innovative approach promoted the production of tolerogenic dendritic cells and regulatory T-cells with subsequent inhibition of T-cell priming and differentiation, along with a significant reduction of donor-specific T-cells in the spleen and grafts of treated animals. This new application of donor-type ECP-treated leukocytes provides insight into the mechanisms behind ECP-induced immunoregulation and holds significant promise in the prevention of graft rejection and reduction in need of global immune suppressive therapy in patients following SOT.

Immunogenic and immunotolerogenic effects of extracorporeal photopheresis in high immunological risk kidney recipients. A single center case series

The immunomodulatory effects of extracorporeal photopheresis (ECP) have been used for the treatment of T-cell mediated disorders, such as rejection in organ transplantation. Currently, it is an established therapy for heart and lung rejection, but not for kidney transplantation (KT), where experience is limited. In addition, some data suggest that ECP could generate an immune response against infections, thus being an alternative for the treatment of rejection in case of active or high-risk of infection. In the present study, we analyze four cases of use of ECP as concomitant therapy in patients with KT and high risk of opportunistic infections due to the high burden of immunosuppression throughout their renal diseases. Two patients had concomitant viral infection (cytomegalovirus and BK virus, respectively) and three patients were on treatment for graft rejection. In the two patients with active viral infection, the infection was successfully controlled during ECP treatment. In all cases, ECP has been shown to be a safe procedure, without complications.

Photopheresis Abates the Anti-HLA Antibody Titer and Renal Failure Progression in Chronic Antibody-Mediated Rejection

Simple Summary

The most common cause of late allograft failure is chronic active antibody-mediated rejection (ABMR), but no effective therapy is available. Different immunosuppressive drugs in combination with procedures that remove serum antibodies have been used and the results have not shown to improve graft and patient outcome, but only an increased risk of adverse events. Extracorporeal pho-topheresis (ECP) is leukapheresis-based immunomodulatory therapy not associated with adverse effect, in which lymphocytes treat-ed with 8-methoxypsoralen (8-MOP) are irradiated with ultraviolet-A (UVA) ex vivo and re-infused into the patient. In this study we investigated therapeutic long-term effect of ECP in patients with biopsy proved chronic ABMR.

Abstract

Objective: Chronic renal antibody-mediated rejection (ABMR) is a common cause of allograft failure, but an effective therapy is not available. Extracorporeal photopheresis (ECP) has been proven successful in chronic lung and heart rejection, and graft versus host disease. The aim of this study was to evaluate the effectiveness of ECP in chronic ABMR patients. Patients and Methods: We investigated ECP treatment in 14 patients with biopsy-proven chronic ABMR and stage 2–3 chronic renal failure. The primary aim was to e valuate the eGFR lowering after 1 year of ECP therapy. The ECP responders (R) showed eGFR reduction greater than 20% vs the basal levels. We also evaluated the effectiveness of ECP on proteinuria, anti-HLA antibodies (HLAab), interleukin 6 (IL-6) serum levels, and CD3, CD4, CD8, CD19, NK, Treg and T helper 17 (Th17) circulating cells. Results: Three patients dropped out of the study. The R patients were eight (72.7%) out of the 11 remaining patients. Because ECP was not associated with any adverse reaction, the R patients continued such treatment for up to 3 years, showing a persisting eGFR stabilization. Twenty four hour proteinuria did not increase in the R patients over the follow-up when compared to the non-responder patients (NR). In the R patients, the HLAab levels were reduced and completely cleared in six out of eight patients when compared with the NR patients. The NR HLAab levels also increased after the discontinuation of the ECP. The ECP in the R patients showed a decrease in CD3, CD4, CD8, CD19, and NK circulating cells. The ECP treatment in the R patients also induced Tregs and Th17 cell increases, and a decrease of the IL-6 serum levels. Conclusions: ECP abates the HLAab titer and renal failure progression in patients with chronic renal ABMR, modulating the immune cellular and humoral responses.

European dermatology forum: Updated guidelines on the use of extracorporeal photopheresis 2020 - Part 2

Background

Following the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T‐cell lymphoma published in 1983, this technology has received continued use and further recognition for additional earlier as well as refractory forms. After the publication of the first guidelines for this technology in the JEADV in 2014, this technology has maintained additional promise in the treatment of other severe and refractory conditions in a multidisciplinary setting. It has confirmed recognition in well‐known documented conditions such as graft‐vs.‐host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection including lung, heart and liver and to a lesser extent inflammatory bowel disease.

Materials and methods

In order to further provide recognized expert practical guidelines for the use of this technology for all indications, the European Dermatology Forum (EDF) again 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. All authors had the opportunity to review each contribution as it was added.

Results and conclusion

These updated 2020 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. The guidelines were divided into two parts: PART I covers Cutaneous T‐cell lymphoma, chronic graft‐vs.‐host disease and acute graft‐vs.‐host disease, while PART II will cover scleroderma, solid organ transplantation, Crohn’s disease, use of ECP in paediatric patients, atopic dermatitis, type 1 diabetes, pemphigus, epidermolysis bullosa acquisita and erosive oral lichen planus.

Extracorporeal photopheresis for the treatment of graft rejection in 33 adult kidney transplant recipients

Background - Extracorporeal photopheresis (ECP) has shown encouraging results in the prevention of allograft rejection in heart transplantation. However, the role of ECP in kidney transplant (KT) rejection needs to be determined. Methods - This multicentre retrospective study included 33 KT recipients who were treated with ECP for allograft rejection (23 acute antibody-mediated rejections (AMRs), 2 chronic AMRs and 8 acute cellular rejections (ACRs)). The ECP indications were KT rejection in patients who were resistant to standard therapies (n = 18) or in patients for whom standard therapies were contraindicated because of concomitant infections or cancers (n = 15). Results - At 12 months (M12) post-ECP, 11 patients (33%) had a stabilization of kidney function with a graft survival rate of 61%. The Banff AMR score (g + ptc + v) was a risk factor for graft loss at M12 (HR 1.44 [1.01-2.05], p < 0.05). The factorial mixed data analysis identified 2 clusters. Patients with a functional graft at M12 tended to have cellular and/or chronic rejections. Patients with graft loss at M12 tended to have acute rejections and/or AMR; higher serum creatinine levels; DSA levels and histologic scores of AMR; and a longer delay between the rejection and ECP start than those of patients with functional grafts. Conclusions - ECP may be helpful to control ACR or moderate AMR in KT recipients presenting concomitant opportunistic infections or malignancies when it is initiated early.

Extracorporeal Photopheresis for Bronchiolitis Obliterans Syndrome After Lung Transplantation

BACKGROUND

Lung transplantation is a therapeutic option for select patients with end-stage lung disease. However, successful lung transplantation is hampered by chronic lung allograft dysfunction, in particular bronchiolitis obliterans syndrome (BOS). Although there is no approved or standard treatment for BOS, which may have several distinct phenotypes, extracorporeal photopheresis (ECP) has shown promising results in patients who develop BOS refractory to azithromycin treatment.

METHODS

We reviewed all relevant clinical data indexed on PubMed from 1987 to 2017 to evaluate the role of ECP in patients with BOS.

RESULTS

Seven small studies investigated the immunomodulatory effects of ECP in patients after solid organ transplant, and 12 studies reported clinical data specific to ECP therapy for BOS. Studies indicate that ECP triggers an apoptotic cellular cascade that exerts various immunomodulatory effects mediated via increases in anti-inflammatory cytokines, a decrease in proinflammatory cytokines, and an increase in tolerogenic regulatory T cells. Clinical evidence derived from relatively small single-center studies suggests that ECP therapy is associated with improvement or stabilization in lung function and sustainable, statistically significant, decreases in the rate of lung function decline in patients with BOS. Additionally, when adverse event data were reported, ECP was generally well tolerated. None of the comparative studies were randomized.

CONCLUSIONS

Immunomodulation mediated via ECP is a rational therapeutic option that may improve clinical outcomes in patients with BOS, particularly in the context of in-depth patient phenotyping as part of a stratified approach to treatment; good quality randomized controlled trials are needed to confirm observational findings.

The role of extracorporeal photopheresis in the management of cutaneous T-cell lymphoma, graft-versus-host disease and organ transplant rejection: a consensus statement update from the UK Photopheresis Society

Extracorporeal photopheresis (ECP) has been used for over 35 years in the treatment of erythrodermic cutaneous T‐cell lymphoma (CTCL) and over 20 years for chronic and acute graft‐versus‐host disease (GvHD) and solid organ transplant rejection. ECP for CTCL and GvHD is available at specialised centres across the UK. The lack of prospective randomised trials in ECP led to the development of UK Consensus Statements for patient selection, treatment schedules, monitoring protocols and patient assessment criteria for ECP. The recent literature has been reviewed and considered when writing this update. Most notably, the national transition from the UVAR XTS^® machine to the new CELLEX machine for ECP with dual access and a shorter treatment time has led to relevant changes in these schedules. This consensus statement updates the previous statement from 2007 on the treatment of CTCL and GvHD with ECP using evidence based medicine and best medical practise and includes guidelines for both children and adults.

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.

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.

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.

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.