Extracorporeal Photopheresis for Bronchiolitis Obliterans Syndrome After Lung Transplantation. Transplantation. 2018;102:1059-1065. [PMID: 29557913 DOI: 10.1097/tp.0000000000002168]

Early extracorporeal photopheresis treatment is associated with better survival in patients with chronic or recurrent acute lung allograft dysfunction

BACKGROUND

Due to development of chronic lung allograft dysfunction (CLAD), prognosis for patients undergoing lung transplantation (LTx) is still worse compared to other solid organ transplant recipients. Treatment options for slowing down CLAD progression are scarce with extracorporeal photopheresis (ECP) as an established rescue therapy. The aim of the study was to identify characteristics of responders and non-responders to ECP treatment, assess their survival, lung function development and by that define the subset of patients who should receive early ECP treatment.

METHODS

We performed a retrospective study of all LTx patients receiving ECP treatment at the University Hospital Zurich between January 2010 and March 2020. Patients were followed-up for a maximum period of 5 years. Mortality and lung function development were assessed by CLAD stage and by CLAD subtype before initiation of ECP treatment.

RESULTS

Overall, 105 patients received at least one ECP following LTx. A total of 57 patients (61.3%) died within the study period with a median survival of 15 months. Mortality was 57% for patients who started ECP at CLAD1, 39% for CLAD2, 93% for CLAD3, and 90% for CLAD4 (p < 0.001). Survival and lung function development was best in young patients at early CLAD stages 1 and 2. Response to ECP treatment was worst in patients with CLAD-RAS/mixed subtype (14.3%) and patients with ECP initiation in CLAD stages 3 (7.1%) and 4 (11.1%). Survival was significantly better in a subset of patients with recurrent acute allograft dysfunction and earlier start of ECP treatment (105 vs 15 months).

CONCLUSION

In this retrospective analysis of a large group of CLAD patients treated with ECP after LTx, early initiation of ECP was associated with better long-term survival. Besides a subset of patients suffering of recurrent allograft dysfunction, especially a subset of patients defined as responders showed an improved response rate and survival, suggesting that ECP should be initiated in early CLAD stages and young patients. ECP might therefore prevent long-term disease progression even in patients with CLAD refractory to other treatment options and thus prevent or delay re-transplantation.

Advances in lung transplantation: 60 years on

Lung transplantation is a well-established treatment for advanced lung disease, improving survival and quality of life. Over the last 60 years all aspects of lung transplantation have evolved significantly and exponential growth in transplant volume. This has been particularly evident over the last decade with a substantial increase in lung transplant numbers as a result of innovations in donor utilization procurement, including the use donation after circulatory death and ex-vivo lung perfusion organs. Donor lungs have proved to be surprisingly robust, and therefore the donor pool is actually larger than previously thought. Parallel to this, lung transplant outcomes have continued to improve with improved acute management as well as microbiological and immunological insights and innovations. The management of lung transplant recipients continues to be complex and heavily dependent on a tertiary care multidisciplinary paradigm. Whilst long term outcomes continue to be limited by chronic lung allograft dysfunction improvements in diagnostics, mechanistic understanding and evolutions in treatment paradigms have all contributed to a median survival that in some centres approaches 10 years. As ongoing studies build on developing novel approaches to diagnosis and treatment of transplant complications and improvements in donor utilization more individuals will have the opportunity to benefit from lung transplantation. As has always been the case, early referral for transplant consideration is important to achieve best results.

The value of extracorporeal photopheresis as an immunosuppression-modifying approach in solid organ transplantation: a potential solution to an unmet medical need

Allograft rejection is a critical issue following solid organ transplantation (SOT). Immunosuppressive therapies are crucial in reducing risk of rejection yet are accompanied by several significant side effects, including infection, malignancy, cardiovascular diseases, and nephrotoxicity. There is a current unmet medical need with a lack of effective minimization strategies for these side effects. Extracorporeal photopheresis (ECP) has shown potential as an immunosuppression (IS)-modifying technique in several SOT types, with improvements seen in acute and recurrent rejection, allograft survival, and associated side effects, and could fulfil this unmet need. Through a review of the available literature detailing key areas in which ECP may benefit patients, this review highlights the IS-modifying potential of ECP in the four most common SOT procedures (heart, lung, kidney, and liver transplantation) and highlights existing gaps in data. Current evidence supports the use of ECP for IS modification following SOT, however there is a need for further high-quality research, in particular randomized control trials, in this area.

Extracorporeal photopheresis (ECP) in the treatment of chronic lung allograft dysfunction (CLAD): a prospective, multicentre, open-label, randomised controlled trial studying the addition of ECP to standard care in the treatment of bilateral lung transplant patients with CLAD (E-CLAD UK)

BACKGROUND

Long-term survival after lung transplantation is limited compared with other organ transplants. The main cause is development of progressive immune-mediated damage to the lung allograft. This damage, which can develop via multiple immune pathways, is captured under the umbrella term chronic lung allograft dysfunction (CLAD). Despite the availability of powerful immunosuppressive drugs, there are presently no treatments proven to reverse or reliably halt the loss of lung function caused by CLAD. The aim of the E-CLAD UK trial is to determine whether the addition of immunomodulatory therapy, in the form of extracorporeal photopheresis (ECP), to standard care is more efficacious at stabilising lung function in CLAD compared with standard care alone.

METHODS AND ANALYSIS

E-CLAD UK is a Phase II clinical trial of an investigational medicinal product (Methoxsalen) delivered to a buffy coat prepared via an enclosed ECP circuit. Target recruitment is 90 bilateral lung transplant patients identified as having CLAD and being treated at one of the five UK adult lung transplant centres. Participants will be randomised 1:1 to intervention plus standard of care, or standard of care alone. Intervention will comprise nine ECP cycles spread over 20 weeks, each course involving two treatments of ECP on consecutive days. All participants will be followed up for a period of 24 weeks.The primary outcome is lung function stabilisation derived from change in forced expiratory volume in one second and forced vital capacity at 12 and 24 weeks compared with baseline at study entry. Other parameters include change in exercise capacity, health-related quality of life and safety. A mechanistic study will seek to identify molecular or cellular markers linked to treatment response and qualitative interviews will explore patient experiences of CLAD and the ECP treatment.A patient and public advisory group is integral to the trial from design to implementation, developing material to support the consent process and interview materials.

ETHICS AND DISSEMINATION

The East Midlands-Derby Research Ethics Committee has provided ethical approval (REC 22/EM/0218). Dissemination will be via publications, patient-friendly summaries and presentation at scientific meetings.

TRIAL REGISTRATION NUMBER

EudraCT number 2022-002659-20; ISRCTN 10615985.

Extracorporeal photopheresis reduces inflammation and joint damage in a rheumatoid arthritis murine model

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammatory reactions and tissue damage in the joints. Long-term drug use in clinical practice is often accompanied by adverse reactions. Extracorporeal photopheresis (ECP) is an immunomodulatory therapy with few side effects, offering a potential and safe therapeutic alternative for RA through the induction of immune tolerance. This study aimed to investigate the therapeutic effects of ECP on RA using a collagen-induced arthritis (CIA) murine model, as well as to explore its immunomodulatory effects in vivo. Additionally, particular attention was given to the significant role of monocytes during the ECP process.

METHODS

A murine model of rheumatoid arthritis was established by administering two injections of bovine type II collagen to DBA/1J mice. ECP, ECP-MD (mononuclear cells were depleted during the ECP), MTX, and PBS treatment were applied to the CIA mice. During the treatment process, clinical scores and body weight changes of CIA mice were closely monitored. After six treatment sessions, micro-CT images of the hind paws from live mice were captured. Ankle joints and paws of the mice were collected and processed for histological evaluation. Spleen samples were collected to measure the Th17/Treg cells ratio, and serum samples were collected to assess cytokine and anti-type II collagen IgG levels. Monocytes and dendritic cells populations before and after ECP in vitro were detected by flow cytometry.

RESULT

ECP therapy significantly attenuated the progression of CIA, alleviated the severity of clinical symptoms in CIA mice and effectively suppressed synovial hyperplasia, inflammation, and cartilage damage. There was an expansion in the percentage of CD3 + CD4 + CD25 + FoxP3 + Tregs and a decrease in CD3 + CD4 + IL17A + Th17 cells in vivo. Furthermore, ECP reduced the serum levels of pro-inflammatory cytokines IL-6 (53.47 ± 7.074 pg/mL vs 5.142 ± 1.779 pg/mL, P < 0.05) and IL-17A (3.077 ± 0.401 pg/mL vs 0.238 ± 0.082 pg/mlL, P < 0.0001) compared with PBS. Interestingly, the depletion of monocytes during the ECP process did not lead to any improvement in clinical symptoms or histological scores in CIA mice. Moreover, the imbalance in the Th17/Treg cells ratio became even more pronounced, accompanied by an augmented secretion of pro-inflammatory cytokines IL-6 and IL-17A. In vitro, compared with cells without ECP treatment, the proportion of CD11b + cells were significantly reduced (P < 0.01), the proportion of CD11c + cells were significantly elevated (P < 0.001) 24 h after ECP treatment. Additionally, the expression of MHC II (P < 0.0001), CD80 (P < 0.01), and CD86 (P < 0.001) was downregulated in CD11c + cells 24 h after ECP treatment.

CONCLUSION

Our study demonstrates that ECP exhibits a therapeutic effect comparable to conventional therapy in CIA mice, and the protective mechanisms of ECP against RA involve Th17/Treg cells ratio, which result in decreased IL-6 and IL-17A. Notably, monocytes derived from CIA mice are an indispensable part to the efficacy of ECP treatment, and the proportion of monocytes decreased and the proportion of tolerogenic dendritic cells increased after ECP treatment in vitro.

The use of extracorporeal photopheresis in solid organ transplantation-current status and future directions

Prevention and management of allograft rejection urgently require more effective therapeutic solutions. Current immunosuppressive therapies used in solid organ transplantation, while effective in reducing the risk of acute rejection, are associated with substantial adverse effects. There is, therefore, a need for agents that can provide immunomodulation, supporting graft tolerance, while minimizing the need for immunosuppression. Extracorporeal photopheresis (ECP) is an immunomodulatory therapy currently recommended in international guidelines as an adjunctive treatment for the prevention and management of organ rejection in heart and lung transplantations. This article reviews clinical experience and ongoing research with ECP for organ rejection in heart and lung transplantations, as well as emerging findings in kidney and liver transplantation. ECP, due to its immunomodulatory and immunosuppressive-sparing effects, offers a potential therapeutic option in these settings, particularly in high-risk patients with comorbidities, infectious complications, or malignancies.

Exosomal-miRNas expression and growth factors released by mononuclear cells of CLAD patients in response to extracorporeal photopheresis

BACKGROUND

CLAD (Chronic Lung Allograft Dysfunction) remains a serious complication following lung transplantation. Some evidence shows that portions of Extracorporeal Photopheresis (ECP)-treated patients improve/stabilize their graft function. In spite of that, data concerning molecular mechanisms are still lacking. Aims of our study were to assess whether ECP effects are mediated by Mononuclear Cells (MNCs) modulation in term of microRNAs (miRNAs) expression and growth factors release.

METHODS

Cells from leukapheresis of 16 CLAD patients, at time 0 and 6-months (10 cycles), were cultured for 48h ± PHA (10 ug/ml) or LPS (2 ug/ml). Expression levels of miR-146a-5p, miR-155-5p, miR-31-5p, miR181a-5p, miR-142-3p, miR-16-5p and miR-23b-5p in MNCs-exosomes were evaluated by qRT-PCR, while ELISA assessed different growth factors levels on culture supernatants.

RESULTS

Our result showed miR-142-3p down-regulation (p = 0.02) in MNCs of ECP-patients after the 10 cycles and after LPS stimulation (p = 0.005). We also find miR-146a-5p up-regulation in cells after the 10 cycles stimulated with LPS (p = 0.03). Connective tissue growth factor (CTGF) levels significantly decreased in MNCs supernatant (p = 0.04). The effect of ECP is translated into frequency changes of Dendritic Cell (DC) subpopulations and a slight increase in T regulatory cells (Treg) number and a significant decrease in CTGF release.

CONCLUSIONS

ECP might affect regulatory T cell functions, since both miR-142 and miR-146a have been shown to be involved in the regulation of suppressor regulatory T cell functions and DCs. On the other side ECP, possibly by regulating macrophage activation, is able to significantly down modulate CTGF release.

Role of transforming growth factor-β in airway remodelling in bronchiolitis obliterans

Airway remodelling is the main pathological mechanism of bronchiolitis obliterans (BO). Several studies have found that transforming growth factor-β (TGF-β) expression is increased in BO during airway remodelling, where it plays an important role in various biological processes by binding to its receptor complex to activate multiple signalling proteins and pathways. This review examines the role of TGF-β in airway remodelling in BO and its potential as a therapeutic target, highlighting the mechanisms of TGF-β activation and signalling, cellular targets of TGF-β actions, and research progress in TGF-β signalling and TGF-β-mediated processes.

Validation of a new automated irradiation system for off-line ECP

Extracorporeal photopheresis (ECP) is a cell therapy originally employed for cutaneous T cell lymphoma and later for GvHD, solid organ rejection and other immunological diseases demonstrating an excellent safety profile. Mononuclear cell (MNCs) apoptosis triggered by UV-A light irradiation in the presence of 8-methoxypsoralene has a key role in priming the cells, ultimately leading to immunomodulation. We report preliminary data about an evaluation of the new automated irradiator device LUMILIGHT (Pelham Crescent srl) for off-line ECP. Fifteen MNCs samples collected by apheresis from 15 adult patients undergoing ECP at our Center were cultured immediately after irradiation along with untreated samples and evaluated at 24, 48 and 72 h timepoints for T cell apoptosis and viability by flow cytometry with Annexin V and Propide Iodidum staining. Post irradiation Hematocrit (HCT), calculated by the device, was compared with that of the automated cell counter. Bacterial contamination was also tested. In irradiated samples after 24-48 and 72 h, the average total apoptosis was 47 %, 70 % and 82 %, respectively, showing a significant difference from untreated samples; residual viable lymphocytes at 72 h were, on average, 18 %. The greatest initiation of apoptosis occurred from 48 h of irradiation onwards. Average early apoptosis of irradiated samples decreased over time (26 %, 17 % and 10 % at 24, 48 and 72 h, respectively). HCT measured by LUMILIGHT was over-estimated, possibly due to the low pre irradiation red blood cell contamination. Bacterial tests resulted negative. Our study showed the LUMILIGHT device to be a valid instrument for MNCs irradiation with good handling and no major technical problems as well as no adverse events in the patients. Our data need to be confirmed in larger studies.

Conventional and Novel Approaches to Immunosuppression in Lung Transplantation

Most therapeutic advances in immunosuppression have occurred over the past few decades. Although modern strategies have been effective in reducing acute cellular rejection, excess immunosuppression comes at the price of toxicity, opportunistic infection, and malignancy. As our understanding of the immune system and allograft rejection becomes more nuanced, there is an opportunity to evolve immunosuppression protocols to optimize longer term outcomes while mitigating the deleterious effects of traditional protocols.

Extracorporeal Photopheresis Improves Graft Survival in a Full-Mismatch Rat Model of Kidney Transplantation

Extracorporeal photopheresis (ECP) is an immunomodulatory therapy based on the infusion of autologous cellular products exposed to ultraviolet light (UV) in the presence of a photosensitizer. The study evaluates the ECP efficacy as induction therapy in a full-mismatch kidney transplant rat model. Dark Agouti to Lewis (DA-L) kidney transplant model has been established. ECP product was obtained from Lewis rat recipients after DA kidney graft transplantation (Lew^DA). Leukocytes of those Lew^DA rats were exposed to 8-methoxy psoralen, and illuminated with UV-A. The ECP doses assessed were 10 × 10⁶ and 100 × 10⁶ cells/time point. Lewis recipients received seven ECP infusions. DA-L model was characterized by the appearance of donor-specific antibodies (DSA) and kidney function deterioration from day three after kidney transplant. The dysfunction progressed rapidly until graft loss (6.1 ± 0.5 days). Tacrolimus at 0.25 mg/kg prolonged rat survival until 11.4 ± 0.7 days (p = 0.0004). In this context, the application of leukocytes from LewDA sensitized rats accelerated the rejection (8.7 ± 0.45, p = 0.0012), whereas ECP product at high dose extended kidney graft survival until 26.3 ± 7.3 days, reducing class I and II DSA in surviving rats. ECP treatment increases kidney graft survival in full-mismatch rat model of acute rejection and is a suitable immunomodulatory therapy to be explored in kidney transplantation.

Reprogramming alveolar macrophage responses to TGF-β reveals CCR2+ monocyte activity that promotes bronchiolitis obliterans syndrome

Bronchiolitis obliterans syndrome (BOS) is a major impediment to lung transplant survival and is generally resistant to medical therapy. Extracorporeal photophoresis (ECP) is an immunomodulatory therapy that shows promise in stabilizing BOS patients, but its mechanisms of action are unclear. In a mouse lung transplant model, we show that ECP blunts alloimmune responses and inhibits BOS through lowering airway TGF-β bioavailability without altering its expression. Surprisingly, ECP-treated leukocytes were primarily engulfed by alveolar macrophages (AMs), which were reprogrammed to become less responsive to TGF-β and reduce TGF-β bioavailability through secretion of the TGF-β antagonist decorin. In untreated recipients, high airway TGF-β activity stimulated AMs to express CCL2, leading to CCR2+ monocyte-driven BOS development. Moreover, we found TGF-β receptor 2-dependent differentiation of CCR2+ monocytes was required for the generation of monocyte-derived AMs, which in turn promoted BOS by expanding tissue-resident memory CD8+ T cells that inflicted airway injury through Blimp-1-mediated granzyme B expression. Thus, through studying the effects of ECP, we have identified an AM functional plasticity that controls a TGF-β-dependent network that couples CCR2+ monocyte recruitment and differentiation to alloimmunity and BOS.

Effective Extracorporeal Photopheresis of Patients with Transplantation Induced Acute Intestinal GvHD and Bronchiolitis Obliterans Syndrome

Background: Patients with steroid-refractory intestinal acute graft-versus-host disease (aGvHD) and bronchiolitis obliterans syndrome (BOS) represent a population with a high need for alternative and effective treatment options. Methods: We report real-life data from 18 patients treated with extracorporeal photopheresis (ECP). This cohort consisted of nine patients with steroid-refractory intestinal aGvHD and nine patients with BOS. Results: We document partial or complete clinical response and reduction of symptoms in half of the patients with intestinal acute GvHD and patients with BOS treated ECP. Responding patients tended to stay on treatment longer. In patients with BOS, stabilization of lung function and forced expiratory volume was observed, whereas, less abdominal pain, less diarrhea, and a reduction of systemic corticosteroids were seen in patients with intestinal acute GvHD. Conclusions: ECP might not only abrogate symptoms but also reduce mortality caused by complications from high-dose steroid treatment. Taken together, ECP offers a serious treatment avenue for patients with steroid-refractory intestinal acute GvHD and BOS.

Effect of azithromycin on bronchiolitis obliterans syndrome in posttransplant recipients: A systematic review and meta-analysis

BACKGROUND

Bronchiolitis obliterans syndrome (BOS) is a devastating complication that occurs after transplantation. Although azithromycin is currently used for the treatment of BOS, the evidence is sparse and controversial. The aim of this meta-analysis is to evaluate the effects of azithromycin on forced expiratory volume in 1 second (FEV1) and patient's survival.

METHODS

PubMed, Embase, Cochrane library, Web of Science databases, and the ClinicalTrials.gov registry were systematically searched from inception until December 2020 for relevant original research articles. Random-effects models were used to calculate pooled-effect estimates.

RESULTS

Searches identified 15 eligible studies involving 694 participants. For FEV1 (L), there was a significant increase after short-term (≤12 weeks; P = .00) and mid-term (12-24 weeks; P = .01) administration of azithromycin. For FEV1 (%) compared to baseline, there was a significant increase after short-term (≤12 weeks) administration of azithromycin (P = .02), while there were no statistically significant differences in the medium and long term. When pooled FEV1% was predicted, it exhibited a similar trend to FEV1 (%) compared to baseline. In addition, we discovered that azithromycin reduced the risk of death (hazard ratio = 0.26; 95% confidence interval = 0.17 to 0.40; P = .00) in patients with BOS post-lung transplantation.

CONCLUSIONS

Azithromycin therapy is both effective and safe for lung function improvement in patients with posttransplant BOS after the short- and medium-term administration. Additionally, it has been demonstrated a significant survival benefit among patients with BOS post-lung transplant. Higher quality randomized controlled trials and more extensive prospective cohort studies are needed to confirm the effect of azithromycin on patients with posttransplant BOS.

Pharmacotherapy of chronic lung allograft dysfunction post lung transplantation

Chronic lung allograft dysfunction (CLAD) remains the primary cause of death in lung transplant recipients (LTRs) in spite of improvements in immunosuppression management. Despite advances in knowledge regarding the pathogenesis of CLAD, treatments that are currently available are usually ineffective and delay progression of disease at best. There are currently no evidence-based guidelines for the optimal treatment of CLAD, and management varies widely across transplant centers. Additionally, there are minimal publications available to summarize data for currently available therapies and outcomes in LTRs. We identified the major domains of the medical management of CLAD and conducted a comprehensive search of PubMed and Embase databases to identify articles published from inception to December 2021 related to CLAD in LTRs. Studies published in English pertaining to the pharmacologic prevention and treatment of CLAD were included; highest priority was given to prospective, randomized, controlled trials if available. Prospective observational and retrospective controlled trials were prioritized next, followed by retrospective uncontrolled studies, case series, and finally case reports if the information was deemed to be pertinent. Reference lists of qualified publications were also reviewed to find any other publications of interest that were not found on initial search. In the absence of literature published in the aforementioned databases, additional articles were identified by reviewing abstracts presented at the International Society for Heart and Lung Transplantation and American Transplant Congress annual meetings between 2010-2021. This document serves to provide a comprehensive review of the literature and considerations for the prevention and medical management of CLAD. This article is protected by copyright. All rights reserved.

Mechanisms of Action of Extracorporeal Photopheresis in the Control of Bronchiolitis Obliterans Syndrome (BOS): Involvement of Circulating miRNAs

Clinical evidence suggests an improvement or stabilization of lung function in a fraction of patients with bronchiolitis obliterans syndrome (BOS) treated by extracorporeal photopheresis (ECP); however, few studies have explored the epigenetic and molecular regulation of this therapy. The aim of present study was to evaluate whether a specific set of miRNAs were significantly regulated by ECP. Total RNA was isolated from serum of patients with established BOS grade 1–2 prior to the start and after 6 months of ECP treatment. We observed a significant downregulation of circulating hsa-miR-155-5p, hsa-miR-146a-5p and hsa-miR-31-5p in BOS patients at the start of ECP when compared to healthy subjects. In responders, increased miR-155-5p and decreased miR-23b-3p expression levels at 6 months were found. SMAD4 mRNA was found to be a common target of these two miRNAs in prediction pathways analysis, and a significant downregulation was found at 6 months in PBMCs of a subgroup of ECP-treated patients. According to previous evidence, the upregulation of miR-155 might be correlated with a pro-tolerogenic modulation of the immune system. Our analysis also suggests that SMAD4 might be a possible target for miR-155-5p. Further longitudinal studies are needed to address the possible role of miR-155 and its downstream targets.

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.

Overexpression of the MSK1 Kinase in Patients With Chronic Lung Allograft Dysfunction and Its Confirmed Role in a Murine Model

BACKGROUND

Chronic lung allograft dysfunction (CLAD) and its obstructive form, the obliterative bronchiolitis (OB), are the main long-term complications related to high mortality rate postlung transplantation. CLAD treatment lacks a significant success in survival. Here, we investigated a new strategy through inhibition of the proinflammatory mitogen- and stress-activated kinase 1 (MSK1) kinase.

METHODS

MSK1 expression was assessed in a mouse OB model after heterotopic tracheal allotransplantation. Pharmacological inhibition of MSK1 (H89, fasudil, PHA767491) was evaluated in the murine model and in a translational model using human lung primary fibroblasts in proinflammatory conditions. MSK1 expression was graded over time in biopsies from a cohort of CLAD patients.

RESULTS

MSK1 mRNA progressively increased during OB (6.4-fold at D21 posttransplantation). Inhibition of MSK1 allowed to counteract the damage to the epithelium (56% restoration for H89), and abolished the recruitment of MHCII+ (94%) and T cells (100%) at the early inflammatory phase of OB. In addition, it markedly decreased the late fibroproliferative obstruction in allografts (48%). MSK1 inhibitors decreased production of IL-6 (whose transcription is under the control of MSK1) released from human lung fibroblasts (96%). Finally, we confirmed occurrence of a 2.9-fold increased MSK1 mRNA expression in lung biopsies in patients at 6 months before CLAD diagnosis as compared to recipients with stable lung function.

CONCLUSIONS

These findings suggest the overall interest of the MSK1 kinase either as a marker or as a potential therapeutic target in lung dysfunction posttransplantation.

Analysis of extracorporeal photopheresis within the frame of the WAA register

The aim of the study was to investigate safety and if extracorporeal photopheresis (ECP) may change health criteria (HC) and quality of life (QoL).

MATERIAL AND METHOD

560 patients (33 % women) were treated with ECP for a total of 13,871 procedures during a 17-years period. Mean age was 48 years (±18, range 3-81 years). Self-estimation of QoL was graded: 0 (suicidal) up to 10 (best ever) and HC: 0 (Bed ridden, ICU condition) up to 10 (athletic). Adverse events were analyzed. ANOVA and paired comparisons were performed.

RESULTS

Patients were treated due to graft versus host disease (GVHD, n = 317), skin lymphoma (n = 70), solid organ transplants (n = 47), skin diseases (n = 20) and other diseases (n = 106). Adverse events (AEs) were registered in 5.4 % of the first treatments and in 1.2 % of the subsequent procedures. Severe AEs were present in 0.04 % of all procedures. No patient died due to the procedure. Tingling and stitching were the most common AE. For those with GVHD an improvement was noticed within approximately 10 procedures of ECP in the severity stage, QoL (from a mean of 6.1 to 6.8, p < 0.002) and the HC (6.1 -> 6.4, p < 0.014) and improved further with added procedures.

CONCLUSION

Photopheresis is an established therapy with few side effects. The present study of soft variables indicate that GVHD shows benefits upon ECP within approximately 10 procedures in regard to the severity of mainly skin GVHD, and lower baseline levels of HC and QoL.

CD11c+ dendritic cells mediate antigen-specific suppression in extracorporeal photopheresis

Extracorporeal photopheresis (ECP) represents one of the most widespread and effective cell therapies for graft‐versus‐host disease and other T cell‐mediated disorders. However, the key factors affecting the therapeutic efficacy of ECP remain unclear. We hypothesized that therapeutic effects are mediated by ECP‐treated antigen‐presenting dendritic cells (DC). To test this hypothesis, we used the experimental model of contact hypersensitivity (CHS). The ECP’s therapeutic activity improved when the total cell dose of the ECP‐treated cells was increased. We used different haptens during sensitization to demonstrate that the anti‐inflammatory activity of ECP is antigen‐specific. This confirmed the hypothesis that professional antigen‐presenting cells are involved in the mode of action. Also, the ECP’s therapeutic activity was abrogated by the depletion of CD11c⁺ DC, which represents fewer than 1% of all the ECP‐exposed cells. Finally, we confirm the critical importance of CD11c⁺ DC for ECP activity by showing that only a few purified CD11c⁺ DC are sufficient to mediate its therapeutic effect. The finding that ECP‐treated, physiological antigen‐presenting DC alone mediate antigen‐specific modulation of a pathological immune response may result in better‐targeted interventions when treating patients.

Outcomes Following Extracorporeal Photopheresis for Chronic Lung Allograft Dysfunction Following Lung Transplantation: A Single-Center Experience

INTRODUCTION

Survival following lung transplantation (LTx) is limited by the development of chronic lung allograft dysfunction (CLAD), for which there are few effective therapies and no standardized management. Several small studies have demonstrated the effectiveness of extracorporeal photopheresis (ECP) as a therapeutic option for CLAD.

METHODS

A retrospective descriptive audit of 12 LTx recipients who received rescue ECP for CLAD over 5 years (2013-2018) at the Alfred Hospital, Melbourne, Australia, was completed. Nonresponders to ECP were defined as patients who experienced a 20% decrease in forced expiratory volume (FEV₁) within 6 weeks of commencing therapy.

RESULTS

Mean time since LTx was 849 days and mean time since diagnosis of CLAD was 131 days. Fifty-eight percent of patients were male (n = 7) and 67% responded to ECP therapy (n = 8). Among responders, the mean (95% confidence interval) decline in FEV₁ pre-ECP was 9.0 mL/day (5-12 mL/day), compared to 1.4 mL/day (0-4 mL/day) post-ECP (P = .01). Among nonresponders, mean (95% confidence interval) decline in FEV₁ was 7.2 mL/day (4-10 mL/day) pre-ECP and 5.0 mL/day (3-7 mL/day) post ECP (P = .2). Nonresponders were more likely to be female (P = .01) and neutropenic (P = .005). Patients with prior exposure to anti-thymocyte globulin had a lowered response to ECP.

CONCLUSION

Rescue ECP arrested the decline of lung function in 67% of patients with CLAD. Sex, pre-ECP neutrophil count, and exposure to anti-thymocyte globulin may help determine response to ECP. Future clinical trials are needed to confirm this effect, help predict response to therapy, and ultimately guide the placement of ECP in the treatment algorithm for CLAD.

Extracorporeal Photopheresis: A Case of Immunotherapy Ahead of Its Time

Extracorporeal photopheresis (ECP) is a cell-based immunotherapy that involves the reinfusion of autologous leukocytes after exposure to psoralen and UVA. The treatment has been used for over 30 years, at first on patients with cutaneous T-cell lymphoma (CTCL) and later for the management of patients with graft-versus-host disease (GvHD), sclerosing disorders, atopic dermatitis, and other diseases that may share the common driving factor of a pathogenic T-cell clone or clones in blood circulation. Patients with clinical improvement mount an antigen-specific immune response that may have tolerance traits in the case of GvHD or anticlonal cytotoxic characteristics in the case of CTCL. The exact mechanisms that dictate one response or the other are not fully understood, but the evidence accumulated so far indicates that multiple events occur simultaneously and consequentially contribute to the end result. These include contact of cells with the outside (plastics and tubing of the ECP apparatus), exposure to psoralen and UVA that activates platelets, monocytes, and other myeloid cells, the release of damage-associated molecular patterns, differentiation of monocytes into dendritic cells, and generation and successive presentation of numerous antigens after the phagocytosis of apoptotic cells. Once reintroduced, the ECP product increases the frequency and activity of regulatory T cells (Tregs), shifts the systemic cytokine balance, and promotes extravasation of immune cells that together shape the effects of this treatment. In this review, we summarize the seminal work and most recent literature of the therapeutic mechanisms and reflect on future avenues of improvements and applications of ECP.

Recent advances into the role of pattern recognition receptors in transplantation

Pattern recognition receptors (PRRs) are germline-encoded sensors best characterized for their critical role in host defense. However, there is accumulating evidence that organ transplantation induces the release or display of molecular patterns of cellular injury and death that trigger PRR-mediated inflammatory responses. There are also new insights that indicate PRRs are able to distinguish between self and non-self, suggesting the existence of non-clonal mechanisms of allorecognition. Collectively, these reports have spurred considerable interest into whether PRRs or their ligands can be targeted to promote transplant survival. This review examines the mounting evidence that PRRs play in transplant-mediated inflammation. Given the large number of PRRs, we will focus on members from four families: the complement system, toll-like receptors, the formylated peptide receptor, and scavenger receptors through examining reports of their activity in experimental models of cellular and solid organ transplantation as well as in the clinical setting.

Therapeutic apheresis in kidney transplantation: An updated review

Therapeutic apheresis is a cornerstone of therapy for several conditions in transplantation medicine and is available in different technical variants. In the setting of kidney transplantation, immunological barriers such as ABO blood group incompatibility and preformed donor-specific antibodies can complicate the outcome of deceased- or living- donor transplantation. Postoperatively, additional problems such as antibody-mediated rejection and a recurrence of primary focal segmental glomerulosclerosis can limit therapeutic success and decrease graft survival. Therapeutic apheresis techniques find application in these issues by separating and selectively removing exchanging or modifying pathogenic material from the patient by an extracorporeal aphaeresis system. The purpose of this review is to describe the available techniques of therapeutic aphaeresis with their specific advantages and disadvantages and examine the evidence supporting the application of therapeutic aphaeresis as an adjunctive therapeutic option to immunosuppressive agents in protocols before and after kidney transplantation.

Controversies and emerging topics in lung transplantation

Lung transplantation provides a realistic hope of improved survival and enhanced quality of life. However, outcomes can be disappointing, meaning many decisions are highly controversial. Practice is largely based on expert opinion and there is a dearth of high-level evidence. Not surprisingly, this leads to centre-specific practices that may vary considerably in controversial areas. The aim of this review, therefore, is to explore some of those domains and present the available evidence. As the science of lung transplantation approaches its fifth decade, we are only now reaching a critical mass of clinicians and scientific researchers to enable adequately powered studies to assist in informing our approach to some of these controversies.

Lung transplantation provides a realistic hope of improved survival and enhanced quality of life. However, outcomes can be disappointing, meaning many decisions are highly controversial. Better evidence is desperately needed.http://ow.ly/Dl4N30maYV9

Extracorporeal Photopheresis-An Overview

Extracorporeal photopheresis (ECP) has been in clinical use for over three decades after receiving FDA approval for the palliative treatment of the Sézary Syndrome variant of cutaneous T-cell lymphoma (CTCL) in 1988. After the first positive experiences with CTCL, additional indications have been successfully explored including areas such as graft-vs.-host disease (GVHD), scleroderma, and solid organ transplantation. The mechanism of action is still not fully resolved, but important steps in understanding ECP in recent years have been very informative. Originally, the primary hypothesis stated that psoralen and ultraviolet A (UVA) in combination induce apoptosis in the treated immune cells. This view shifted in favor of dendritic cell initiation, modification of the cytokine profile and stimulation of several T-cell lineages, in particular regulatory T-cells. A number of ECP guidelines have been produced to optimize treatment regimens in the clinical context. In CTCL, enough evidence is available for the use of ECP as a first line treatment for Sézary Syndrome (SS), but also as a second line or rescue treatment in therapy-refractory forms of mycosis fungoides (MF). ECP in the treatment of acute and chronic GVHD has shown promising results as second line therapy in steroid-refractory presentations. In solid organ transplantation, ECP has been used to increase tissue tolerance and decrease infections with opportunistic pathogens, attributed to the use of high doses of immunosuppressive medication. Infection with cytomegalovirus (CMV) remains a limiting factor affecting survival in solid organ transplantation and the role of ECP will be discussed in this review. A trend toward prophylactic use of ECP can be observed and may further contribute to improve the outcome in many patients. To further deepen our knowledge of ECP and thus facilitate its use in patients that potentially benefit most from it, future prospective randomized trials are urgently needed in this rapidly growing field. The aim of this review is to (1) introduce the method, (2) give an overview where ECP has shown promising effects and has become an essential part of treatment protocols, and (3) to give recommendations on how to proceed in numerous indications.

Lung Transplantation in Idiopathic Pulmonary Fibrosis

Despite the advances in recent years in the treatment of idiopathic pulmonary fibrosis (IPF), it continues to be a progressive disease with poor prognosis. In selected patients, lung transplantation may be a treatment option, with optimal results in survival and quality of life. Currently, pulmonary fibrosis is the main cause of lung transplantation. However, mortality on the waiting list of these patients is high, since many patients are referred to the transplant units with advanced disease. There is not a parameter that can predict the survival of a specific patient. Different variables are to be considered in order to decide the right time to send them to a transplant unit. It is also very difficult to decide when to include these patients on the waiting list. Every patient diagnosed with IPF, without contraindications for surgery, should be referred early to a transplant unit for assessment. A uni or bilateral transplantation will be decided based on the characteristics of the patient and the experience of each center. The post-transplant survival of recipients with IPF is lower than that observed in other diseases, such as cystic fibrosis or chronic obstructive pulmonary disease as a consequence of their older age and the frequent presence of associated comorbidity. Post-transplant follow-up must be tight in order to assure optimal level of immunosuppressive treatment, detect complications associated with it, and avoid graft rejection. The main cause of long-term mortality is late graft dysfunction as a consequence of chronic rejection. Other complications, such as infections and tumors, must be considered.