The immunological effect of photopheresis in children with newly diagnosed type 1 diabetes

European dermatology forum - updated guidelines on the use of extracorporeal photopheresis 2020 - part 1

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 multi‐disciplinary setting. It has confirmed recognition in well‐known documented conditions such as graft‐versus‐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 are divided in two parts: PART I covers cutaneous T‐cell lymphoma, chronic graft‐versus‐host disease and acute graft‐versus‐host disease while PART II will cover scleroderma, solid organ transplantation, Crohn's disease, use of ECP in paediatrics practice, atopic dermatitis, type 1 diabetes, pemphigus, epidermolysis bullosa acquisita and erosive oral lichen planus.

Therapies to Preserve β-Cell Function in Type 1 Diabetes

In spite of modern techniques, the burden for patients with type 1 diabetes mellitus will not disappear, and type 1 diabetes will remain a life-threatening disease causing severe complications and increased mortality. We have to learn of ways to stop the destructive process, preserve residual insulin secretion or even improve the disease via β-cell regeneration. This will give a milder disease, a more stable metabolism, simpler treatment and perhaps even cure. Therapies based on single drugs have not shown sufficient efficacy; however, there are several treatments with encouraging efficacy and no apparent, or rather mild, adverse events. As the disease process is heterogeneous, treatments have to be chosen to fit relevant subgroups of patients, and step by step efficacy can possibly be improved by the use of combination therapies. Thus immunosuppressive therapies like anti-CD3 and anti-CD20 monoclonal antibodies might be combined with fusion proteins such as etanercept [tumor necrosis factor (TNF)-α inhibitor] and/or abatacept (CTLA4-Ig) early after onset to stop the destructive process, supported by β-cell protective agents. The effect may be prolonged by using autoantigen therapy [glutamate decarboxylase (GAD) proinsulin], and by adding agents facilitating β-cell regeneration [e.g. glucagon-like peptide-1 (GLP-1)] there should be a good chance to make the disease milder, perhaps leading to cure in some patients.

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

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.

Altered immune profile from pre-diabetes to manifestation of type 1 diabetes

BACKGROUND

While the mechanisms leading to β-cell destruction and clinical onset of T1D are still unclear, the composition of the immune profile is probably important for the outcome of immune activity. The aim of this study was to investigate the composition and possible changes of the immunological profile, spontaneously and following stimulation with the autoantigens GAD65, and HSP60, at high-risk and T1D onset and further to 8 months post diagnosis.

METHODS

Fifteen first-degree relatives of T1D patients with a high risk of developing the disease within five years, 25 children approximately four days and 8 months after diagnosis of T1D and 16 healthy children were included in the study. Cytokines (IL-1β, -6, -7, -10, -13, -17, IFN-γ and TNF-α) and chemokines (CCL2, -3, -4, -5 and CXCL10) associated with Th1, Th2, Tr1 and inflammatory cells were detected in cell culture supernatants by Luminex-technique, and markers associated with regulatory T-cells (FOXP3, CTLA-4 and TGF-β) by real-time RT-PCR.

RESULTS

High-risk individuals differed in immunity from that seen in healthy and T1D children. High-risk individuals had a low TNF-α response and fewer responders from mitogen exposure as well as low spontaneous secretions of IL-13 compared to healthy children. High-risk individuals that later developed T1D, had a lower FOXP3 and CTLA-4 mRNA expression, following stimulation with GAD65, in combination with higher secretion of the pro-inflammatory chemokine CCL4.

CONCLUSION

Changes in immunity seen in individuals with high risk of developing T1D points to alterations/actions in the immune system already early in the pre-diabetic phase.

Predictors of response to extracorporeal photopheresis in advanced mycosis fungoides and Sézary syndrome

BACKGROUND

Extracorporeal photopheresis (ECP) has been utilized for more than 20 years to treat cutaneous T-cell lymphoma (CTCL), but a clinical response can take up to 9 months to manifest. This study was undertaken to determine whether clinical features, laboratory values, cytokine levels, or gene expression levels of tumor markers are useful to predict the subsequent response to ECP in CTCL patients with blood involvement.

METHODS

Twenty-one patients with CTCL treated with ECP as monotherapy for at least 6 months were retrospectively identified. Laboratory and clinical data and blood obtained at baseline, 3, and 6 months of treatment were used for analysis.

RESULTS

In pretreatment blood specimens, a lower percentage of Sézary cells and a higher absolute eosinophil count were associated with a favorable clinical response. Clinical evidence of an early response after 3 months of ECP did not reliably predict a favorable response at 6 months or beyond. Comparison of cytokines, gene transcripts, and other laboratory measures of disease did not correlate with the subsequent clinical response, although lactate dehydrogenase levels tended to decrease progressively in ECP-responsive cases and increase progressively in ECP-non-responsive cases. Additionally, serum levels of TNF-alpha significantly increased from baseline to 6 months of ECP, but was not found to correlate with the clinical response.

CONCLUSIONS

Although we found that increased eosinophils and decreased percentage of Sézary cells were associated with a favorable clinical response to ECP, we were not able to identify the predictors of ECP response within the first 3 months of treatment.

Cutaneous T cell lymphoma and graft-versus-host disease: a comparison of in vivo effects of extracorporeal photochemotherapy on Foxp3+ regulatory T cells

Extracorporeal photochemotherapy (ECP) is a well established treatment for both cutaneous T cell lymphoma (CTCL) and graft-versus-host disease (GVHD). However, the general effector mechanism is not fully settled. Twenty-four patients with CTCL and 14 patients with GVHD were included to assess the relative numbers of regulatory T cells (Treg) and any change in the serum cytokine profile during 6 months of ECP therapy. The relative amount of Treg cells was twice as high in CTCL compared to GVHD and healthy controls. TGF-beta was on average three times higher in GVHD than in CTCL. Both patient groups had a small but significant increase in TGF-beta after treatment. Our results indicate a strengthened Treg function as a result of ECP. Elevated TGF-beta may indicate high Treg activation in GVHD, whereas an increased number of Treg cells in CTCL could be interpreted as a response that is involved in down-regulating the lymphoma cells.

The role of immunomodulation therapy in autoimmune diabetes

Type 1 diabetes (T1DM) is characterized by loss of virtually all endogenous insulin secretion. If residual insulin secretion is preserved, this will lead to improved metabolic balance, less acute and late complications, improved quality of life, and, in case of pronounced improvement of residual insulin secretion, complete remission and even cure of the disease. Immune suppression or immune modulation have been demonstrated as a proof of principle to stop/decrease the destructive process and thereby preserve beta-cell function. Several methods to save residual beta-cell function have been tried for more than three decades with little or no evidence of efficacy. Positive effects have been seen mainly in adult patients but have been minimal or absent in children with diabetes. Furthermore, the safety of these immune interventions and/or their benefit to risk relationships have not been found to justify clinical use. More specific immune modulation with anti-CD3 monoclonal antibodies has resulted in more encouraging postponement of C-peptide decline, but with frequent and serious adverse effects. Still more promising are the autoantigen therapies, of which glutamic acid decarboxylase (GAD) vaccination has shown significant preservation of residual insulin secretion in 10-18-year-old type 1 diabetes patients with recent onset. Efficacy was most impressive in the subgroup of patients with diabetes of short duration (<3 months). The treatment was simple, well tolerated, and showed no treatment-related adverse events. If these results can be confirmed, there is a realistic hope that GAD vaccination, perhaps in combination with vaccinations with other autoantigens and/or other therapies, will result in remission for some patients. The prospects of cure and prevention of T1DM will become less remote.

In vitro experiments demonstrate that monocytes and dendritic cells are rendered apoptotic by extracorporeal photochemotherapy, but exhibit unaffected surviving and maturing capacity after 30 Gy gamma irradiation

Extracorporeal photochemotherapy (ECP) has been shown to induce apoptosis in lymphocytes. Until recently the prevailing opinion has been that the monocytes were mainly not affected by this treatment. This study has investigated the effect of ECP and gamma irradiation on monocytes and immature dendritic cells (DC) in vitro and followed the ability of the cells to differentiate and survive post treatment. ECP induced apoptosis in lymphocytes, monocytes and immature DC within 72 h following treatment, in contrast to 30 Gy gamma irradiation, which seemed mainly to affect lymphocytes. The minority of the surviving ECP-treated monocytes presented a reduced ability to differentiate into immature DC within this time frame. We also demonstrated that immature DC after ECP-treatment lost their normal ability to mature on stimulation with lipopolysaccharide. As monocytes and immature DC seem to have a reduced ability to differentiate after ECP-treatment, it is suggested that the therapeutic effect of ECP is caused by in vivo effects of reinfused apoptotic cells, rather than by infusion of monocytes induced to differentiate into immature DC.

Regulatory T cell-associated activity in photopheresis-induced immune tolerance in recent onset type 1 diabetes children

Extracorporeal photochemotherapy (ECP) has demonstrated immunological effects. The proposed cytotoxic lymphocyte antigen 4 (CTLA-4) involvement, together with forkhead box P3 (FoxP3) and transforming growth factor (TGF)-beta are associated with regulatory T cell activity. The aim of the study was to evaluate the regulatory T cell-associated effect of ECP in recent onset type 1 diabetic (T1D) children. Children (n = 20) with T1D received photopheresis 8-methoxypsoralen + ECP or placebo + shampheresis. Peripheral blood mononuclear cells (PBMC) collected pretreatment (day 1) and post-treatment (day 90) were stimulated with phytohaemagglutinin (PHA) and T1D-associated glutamic acid decarboxylase 65 (GAD(65)) peptide a.a. 247-279. CTLA-4, sCTLA-4, FoxP3 and TGF-beta mRNA transcription was quantified. Photopheresis-treated individuals' relative mRNA expression was generally maintained during the course of the study. Placebo individuals increased in spontaneous CTLA-4 mRNA (P < 0.05) but decreased in expression after stimulation with GAD(65)-peptide (P < 0.05) and PHA (P < 0.05). Spontaneous TGF-beta (P < 0.05) increased whereas PHA- (P < 0.01) and GAD(65)-peptide (P < 0.01)-induced TGF-beta expression decreased in the placebo group, whereas it was maintained in the treated group. Without intervention, expression of CTLA-4 and TGF-beta, stimulated with PHA and GAD(65) peptide, decreased with time, with a parallel reduction of GAD(65)-peptide and PHA-stimulated TGF-beta expression. These parameters were counteracted by ECP. In conclusion, our results indicate that ECP maintains regulatory T cell-associated activity in recent-onset T1D.

Immune intervention at diagnosis--should we treat children to preserve beta-cell function?

Type 1 diabetes (T1D) is characterized by loss of beta-cell function. If beta-cell function can be preserved, it will lead to improved metabolic balance with improved quality of life and fewer acute and late complications, and if residual insulin secretion improves well enough, then that could lead to complete remission and even cure of the disease. Several efforts to save residual beta-cell function have been made for more than three decades without success. Proof of principle has been possible, and it seems clear that immune suppression or immune modulation, in fact, can stop the destructive process and thereby preserve beta-cell function. However, the effect seen in adult patients with T1D have been minimal or absent in diabetic children who seem to have another or at least more aggressive disease process. Furthermore, the immune interventions have had too serious and common adverse events in comparison to the scarce-positive effect. Recent more specific immune modulation with anti-CD3 monoclonal antibodies seems more encouraging with at least postponement of the C-peptide decline, but unfortunately still with common and quite threatening adverse effects. Even more promising are the autoantigen therapies, of which glutamic acid decarboxylase (GAD) vaccination has shown good results with impressive preservation of residual insulin secretion in 10- to 18-year-old type 1 diabetic patients with recent onset. In patients with short diabetes duration at intervention the effect was remarkable. Furthermore, these effects were achieved with no adverse events. Future studies will show whether the good effect seen so far can be confirmed. If so there is hope that GAD vaccination will cause remission and even cure and prevention of T1D will then no longer be just a dream.

A new device to study ex-vivo the effects of extracorporeal photochemotherapy on the immune system

Extracorporeal photochemotherapy (ECP) is a medical procedure effective in the treatment of several different T-cell mediated diseases such as cutaneous T-cell lymphoma and Graft-versus-Host Disease. During ECP treatment the patient's blood is processed by means of a cell separator to collect leukocytes (leukapheresis), mostly lymphocytes and monocytes, which are then incubated with the photoactive drug 8-methoxypsoralen (8-MOP), exposed to ultraviolet-A light (UV-A) and reinfused to the patient. It has been suggested that during ECP not only UV-A irradiation but also changes in the environmental condition may be relevant. Although ECP has been shown to have an in-vivo immunomodulatory effect, the mechanisms through which ECP exerts its effect remain elusive. One of the reasons for this incomplete knowledge is the absence of a reliable model for ECP. In order to investigate the effect of ECP on the peripheral immune system, we developed a new device which mimics the complete ECP cycle including blood transit through the cell separator. Peripheral blood samples (50ml) were obtained from volunteers and processed using a peristaltic pump. Peripheral blood mononuclear cells (PBMC) were then collected and treated with 8-MOP and UV-A under the same conditions used for the patients' therapy. Using this strategy we investigated 8-MOP, UV-A and their combined effect on the production of the pro-inflammatory cytokines interferon-gamma (IFN-gamma), interleukine-2 (IL-2) and tumor necrosis factor-alpha (TNF-alpha) in PBMC with and without polyclonal stimulation. We firstly demonstrated that our device does not affect total red and white blood cell counts. After 8-MOP and UV-A irradiation a significant decrease was observed in both activated CD4(+) and CD8(+) T lymphocytes producing IFN-gamma, IL-2 and TNF-alpha. Our findings are in line with those previously obtained in humans after complete ECP treatment, thus suggesting that our newly developed device is suitable for investigating the mechanism of action of ECP ex-vivo.