Extracorporeal photopheresis: From solid organs to face transplantation

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.

CD8+ T cells mediate ultraviolet A-induced immunomodulation in a model of extracorporeal photochemotherapy

Extracorporeal photochemotherapy (ECP) that takes advantage of the immunomodulatory effects of UV light has been extensively used for many years for the treatment of several T cell-mediated diseases, including graft-versus-host disease (GvHD) and systemic scleroderma. Immune mechanisms that lead to the establishment of T cell tolerance in ECP-treated patients remain poorly known. In this study, we have tested the effect of UV/psoralen-treated BM-derived dendritic cells, referred to as ECP-BMDCs on the outcome of an antigen-specific T cell-mediated reaction, that is, contact hypersensitivity (CHS), which is mediated by CD8⁺ effector T cells (CD8⁺ T_eff ). The intravenous (i.v.) injection of antigen-pulsed ECP-BMDCs in recipient C57BL/6 mice induced specific CD8⁺ T cells endowed with immunomodulatory properties (referred to as CD8⁺ T_ECP ), which prevented the priming of CD8⁺ T_eff and the development of CHS, independently of conventional CD4⁺ regulatory T cells. CD8⁺ T_ECP mediated tolerance by inhibiting the migration and functions of skin DC and subsequently the priming of CD8⁺ T_eff . CD8⁺ T_ECP displayed none of the phenotypes of the usual CD8⁺ T regulatory cells described so far. Our results reveal an underestimated participation of CD8⁺ T cells to ECP-induced immunomodulation that could explain the therapeutic effects of ECP in T cell-mediated diseases.

Death begets a new beginning

Cell death is a perpetual feature of tissue microenvironments; each day under homeostatic conditions, billions of cells die and must be swiftly cleared by phagocytes. However, cell death is not limited to this natural turnover-apoptotic cell death can be induced by infection, inflammation, or severe tissue injury. Phagocytosis of apoptotic cells is thus coupled to specific functions, from the induction of growth factors that can stimulate the replacement of dead cells to the promotion of tissue repair or tissue remodeling in the affected site. In this review, we outline the mechanisms by which phagocytes sense apoptotic cell death and discuss how phagocytosis is integrated with environmental cues to drive appropriate responses.

Reflections on the usefulness of extracorporeal photopheresis in renal transplant rejection: A concise review of the involved mechanisms and therapeutic perspectives

Renal rejection clinically represents a major cause of graft dysfunction and sadly the loss of the renal transplant. This is despite the considerable progress in immunosuppressive therapy. It is strongly believed that the complex immunologic network underlying the response against major histocompatibility molecules (MHC) is responsible for rejection, an unresolved issue that is, in part, not inhibited by the current prophylactic and therapeutic strategies. Extracorporeal photopheresis (ECP) is an effective cell therapy approach that was successfully used in immunomodulating heart rejection, acute and chronic GvHD, lung rejection and some selected autoimmune diseases. In this concise report we provide a brief review on the mechanisms of action and the use of ECP in acute and chronic renal allograft rejection.

The immunologic considerations in human head transplantation

The idea of head transplantation appears at first as unrealistic, unethical, and futile. Here we discuss immunological considerations in human head transplantation. In a separate accompanying article we discuss surgical, ethical, and psychosocial issues concerned in body-to-head transplantation (BHT) [1]. The success of such an unusual allograft, where the donor and the recipient can reject each other, depends on prevention of complex immunologic reactions, especially rejection of the head by the body (graft-vs-host) or probably less likely, the possibility of the head rejecting the total body allograft (host-vs-graft). The technical and immunologic difficulties are enormous, especially since rapid nerve and cord connections and regeneration have not yet been possible to achieve. In this article we begin by briefly reviewing neuro-immunologic issues that may favor BHT such as the blood brain barrier (BBB) and point out its shortcomings. And we touch on the cellular and humoral elements in the brain proper that differ in some respects from those in other organs and in the periphery. Based on recent successes in vascular composite allografts (VCAs), we will elaborate on potential specific advantages and difficulties in BHT of various available immunosuppressive medications already utilized in VCAs. The risk/benefit ratio of these drugs will be emphasized in relation to direct brain toxicity such as seizure disorders, interference, or promotion of nerve regeneration, and potentiation of cerebral viral infections. The final portion of this article will focus on pre-transplant immunologic manipulation of the deceased donor body along with pretreatment of the recipient.

Face transplant: long-term follow-up and results of a prospective open study

BACKGROUND

More than 30 face transplantations have been done worldwide since 2005 but no documented long-term follow-up has been reported in the literature. We aimed to answer remaining question about the long-term risks and benefits of face transplant.

METHODS

In this single-centre, prospective, open study, we assessed 20 patients presenting with facial defects. Ten patients were selected, and, after three were secondarily excluded, seven were transplanted: two with neurofibromatosis 1, one with a burn, and four with self-inflicted facial gunshot injuries. We report the long-term outcomes of six face allotransplant recipients at an average of 6 years (range 3·4-9 years) after the transplantation. All admissions to hospital except for planned revisions and immunosuppressive follow-up therapy were reported as adverse events (safety endpoint). Predefined immunological, metabolic, surgical, and social integration endpoints were collected prospectively. Patients underwent quantitative health-related quality of life assessments through Short Form 36 health questionnaires. This study was registered with ClinicalTrials.gov, number NCT00527280.

FINDINGS

Two of seven patients died: one at 65 days due to transplant destruction with concomitant pseudomonas infection and the second at 3·4 years after transplantation by suicide. The six patients alive at long-term follow-up presented with functional transplants. Safety endpoints were related to infection in the first month, acute rejection from 1 day to 7 years after transplantation, or side-effects of immunosuppressive therapy. Recurrent rejection episodes justified maintenance therapy with high-dose steroids at high levels in all patients at last follow-up, yet none of the patients developed diabetes. Three patients were found to have hypertension with one requiring therapy. All patients had a noticeable reduction in glomerular filtration rate. All recipients and their families accepted their transplant. Improvements in social integration and quality of life were highly variable among the patients and depended on baseline levels and psychiatric comorbidities.

INTERPRETATION

These long-term results show the crucial effect of patients' social support and pre-existing psychiatric conditions on the risk-benefit ratio of facial transplantation. Careful preoperative patient selection and long-term postoperative follow-up programmes under strict institutional review board controls should be used for any future grafts of this type.

FUNDING

Protocole Hospitalier de Recherche Clinique (PHRC) National.

Apoptotic cell responses in the splenic marginal zone: a paradigm for immunologic reactions to apoptotic antigens with implications for autoimmunity

Apoptotic cells drive innate regulatory responses that result in tolerogenic immunity. This is a critical aspect of cell physiology as apoptotic cells expose potentially dangerous nuclear antigens on the surface in apoptotic blebs, and failure in their recognition, phagocytosis, or destruction can cause dramatic autoimmunity in experimental models and is linked to development and progression of systemic pathology in human. The marginal zone is a specialized splenic environment that serves as a transitional site from circulation to peripheral lymphoid structures. The marginal zone serves a key role in trapping of particulates and initiation of innate responses against systemic microbial pathogens. However in recent years, it has become clear the marginal zone is also important for initiation of immune tolerance to apoptotic cells, driving a coordinated response involving multiple phagocyte and lymphocyte subsets. Recent reports linking defects in splenic macrophage function to systemic lupus erythematosus in a manner analogous to marginal zone macrophages in lupus-prone mice provide an impetus to better understand the mechanistic basis of the apoptotic cell response in the marginal zone and its general applicability to apoptotic cell-driven tolerance at other tissue sites. In this review, we discuss immune responses to apoptotic cells in the spleen in general and the marginal zone in particular, the relationship of these responses to autoimmune disease, and comparisons to apoptotic cell immunity in humans.

Quality control on mononuclear cells collected for extracorporeal photochemotherapy: comparison between two UV-A irradiation devices

Recently, MacoPharma released a new UV-A cell irradiator device (Macogenic G2) for extracorporeal photopheresis (ECP), smaller and lighter than the Macogenic G1 but with no integrated cooling system. We compared the two devices at different working temperatures (G1 at standard irradiation temperature - 21°C - and G2 set by purpose at 34°C) in patients affected with chronic graft-versus-host disease and chronic lung allograft dysfunction treated by ECP. We demonstrate that both G1 and G2 devices are efficient in inducing the inhibition of lymphocytic proliferation and mononuclear cells apoptosis after 48 h even when G2 is set at higher-than-standard temperature.

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.

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.

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.

Integrin-driven monocyte to dendritic cell conversion in modified extracorporeal photochemotherapy

Due to clinical efficacy and safety profile, extracorporeal photochemotherapy (ECP) is a commonly used cell treatment for patients with cutaneous T cell lymphoma (CTCL) and graft-versus-host disease (GVHD). The capacity of ECP to induce dendritic antigen-presenting cell (DC)-mediated selective immunization or immunosuppression suggests a novel mechanism involving pivotal cell signalling processes that have yet to be clearly identified as related to this procedure. In this study we employ two model systems of ECP to dissect the role of integrin signalling and adsorbed plasma proteins in monocyte-to-DC differentiation. We demonstrate that monocytes that were passed through protein-modified ECP plates adhered transiently to plasma proteins, including fibronectin, adsorbed to the plastic ECP plate and activated signalling pathways that initiate monocyte-to-DC conversion. Plasma protein adsorption facilitated 54·2 ± 4·7% differentiation, while fibronectin supported 29·8 ± 7·2% differentiation, as detected by DC phenotypic expression of membrane CD80 and CD86, as well as CD36, human leucocyte antigen D-related (HLA-DR) and cytoplasmic CD83. Further, we demonstrate the ability of fibronectin and other plasma proteins to act through cell adhesion via the ubiquitous arginine-glycine-aspartic (RGD) motif to drive monocyte-to-DC differentiation, with high-density RGD substrates supporting 54·1 ± 5·8% differentiation via αVβ3 and α5β1integrin signalling. Our results demonstrate that plasma protein binding integrins and plasma proteins operate through specific binding domains to induce monocyte-to-DC differentiation in ECP, providing a mechanism that can be harnessed to enhance ECP efficacy.

Induction of monocyte-to-dendritic cell maturation by extracorporeal photochemotherapy: initiation via direct platelet signaling

Extracorporeal Photochemotherapy (ECP) is a widely used therapy for cutaneous T cell lymphoma (CTCL). Although the mechanism of clinical action of ECP is not precisely established, previous studies have shown evidence of induction of dendritic cells (DCs). Here we show that, under flow conditions similar to those in post-capillary venules, ECP promotes platelet immobilization and activation, initiating stepwise receptor-ligand interactions with monocytes, which then differentiate into DC. These findings clarify how ECP directly stimulates DC maturation; suggest a new clinically applicable approach to the obtainment of DC; and identify a novel mechanism that may reflect physiological induction of DC.

Vascularized composite allotransplantation: an update on medical and surgical progress and remaining challenges

BACKGROUND

In vascularized composite allotransplantation, multiple types of tissue are transferred from donor to recipient as a single functional unit. This technique has been performed for upper extremity, face, and abdominal wall transplants, among many others.

OBJECTIVE

To review the existing cases of face and upper extremity vascularized composite allotransplantation performed to date and to describe the functional outcomes and challenges associated with this new procedure. We also review the immune suppression protocols required for these procedures.

METHODS

A literature review was performed using PubMed and online registries where available to identify patients who have undergone upper extremity and face transplant procedures. These were compiled and cross-referenced to abstracts, conference presentations, and press releases in the media to create a list of procedures performed to date.

RESULTS

More than seventy patients have undergone upper extremity transplantation with very good functional outcomes routinely achieved. Twenty-five face transplants were identified that have been completed to date and details regarding patient outcome are included. One cases of human face allotransplantation with pre- and post-operative images is included as an example of what can be achieved with this technique.

CONCLUSIONS

Vascularized composite allotransplantation is an emerging field that provides an exciting new avenue for reconstructive procedures and achieves functional and cosmetic outcomes not previously possible with existing techniques. However, it is not without its challenges and considerable work is still required prior to widespread adoption of these new reconstructive techniques.

Composite tissue allotransplantation and dysregulation in tissue repair and regeneration: a role for mesenchymal stem cells

Vascularized composite tissue allotransplantation is a rapidly evolving area that has brought technological advances to the forefront of plastic surgery, hand surgery, and transplant biology. Composite tissue allografts (CTAs) may have profound functional, esthetic, and psychological benefits, but carry with them the risks of life-long immunosuppression and the inadequate abilities to monitor and prevent rejection. Allografts may suffer from additional insults further weakening their overall benefits. Changes in local blood flow, lack of fully restored neurologic function, infection, inflammation with subsequent dysregulated regenerative activity, and paucity of appropriate growth factors may all be involved in reducing the potential of CTAs and therefore serve as new therapeutic targets to improve outcomes. Strategies involving minimized immunosuppression and pro-regenerative therapy may provide a greater path to optimizing long-term CTA function. One such strategy may include mesenchymal stem cells (MSCs), which can provide unique anti-inflammatory and pro-regenerative effects. Insights gained from new studies with MSCs on composite allografts, advances in tissue regeneration reported in other MSC-based clinical studies, as well as consideration of newly described capacities of MSCs, may provide new regenerative based strategies for the care of CTAs.

Phenotyping established chronic lung allograft dysfunction predicts extracorporeal photopheresis response in lung transplant patients

Chronic lung allograft dysfunction (CLAD) remains the leading cause of mortality in lung transplant recipients after the first year. Treatment remains limited and unpredictable. Existing data suggests extracorporeal photopheresis (ECP) may be beneficial. This study aimed to identify factors predicting treatment response and the prognostic implications. A single center retrospective analysis of all patients commencing ECP for CLAD between November 1, 2007 and September 1, 2011 was performed. In total 65 patients were included, 64 of whom had deteriorated under azithromycin. Median follow-up after commencing ECP was 503 days. Upon commencing ECP, all patients were classified using proposed criteria for emerging clinical phenotypes, including "restrictive allograft syndrome (RAS)", "neutrophilic CLAD (nCLAD)" and "rapid decliners". At follow-up, 8 patients demonstrated ≥10% improvement in FEV1 , 27 patients had stabilized and 30 patients exhibited ≥10% decline in FEV1 . Patients fulfilling criteria for "rapid decliners" (n=21, p=0.005), RAS (n=22, p=0.002) and those not exhibiting neutrophilia in bronchoalveolar lavage (n=44, p=0.01) exhibited poorer outcomes. ECP appears an effective second line treatment in CLAD patients progressing under azithromycin. ECP responders demonstrated improved progression-free survival (median 401 vs. 133 days). Proposed CLAD phenotypes require refinement, but appear to predict the likelihood of ECP response.

Facial transplantation: a concise update

Objectives: Update on clinical results obtained by the first worldwide facial transplantation teams as well as review of the literature concerning the main surgical, immunological, ethical, and follow-up aspects described on facial transplanted patients. Study design: MEDLINE search of articles published on “face transplantation” until March 2012. Results: Eighteen clinical cases were studied. The mean patient age was 37.5 years, with a higher prevalence of men. Main surgical indication was gunshot injuries (6 patients). All patients had previously undergone multiple conventional surgical reconstructive procedures which had failed. Altogether 8 transplant teams belonging to 4 countries participated. Thirteen partial face transplantations and 5 full face transplantations have been performed. Allografts are varied according to face anatomical components and the amount of skin, muscle, bone, and other tissues included, though all were grafted successfully and remained viable without significant postoperative surgical complications. The patient with the longest follow-up was 5 years. Two patients died 2 and 27 months after transplantation. Conclusions: Clinical experience has demonstrated the feasibility of facial transplantation as a valuable reconstructive option, but it still remains considered as an experimental procedure with unresolved issues to settle down. Results show that from a clinical, technical, and immunological standpoint, facial transplantation has achieved functional, aesthetic, and social rehabilitation in severely facial disfigured patients.

Key words:Face transplantation, composite tissue transplantation, face allograft, facial reconstruction, outcomes and complications of face transplantation.

Face allotransplantation and burns: a review

Burns may represent one of the main indications for face allotransplantation. Severely disfigured faces featuring a devastating appearance and great functional impairments are not only seen as burn sequelae but also occur as a result of other traumatic injuries, oncological surgical resections, benign tumors (eg, neurofibromatosis), and major congenital malformations. To date, 20 human face composite tissue allotransplants have been performed with success. Despite the initial scepticism about its applicability, due mainly to ethical and technical reasons, the previous worldwide cases and their associated positive outcomes, including acceptable immunosuppressive regimens, excellent aesthetic and functional results, and good psychological acceptance by the recipient, enable the conclusion that face composite tissue allotransplantation has become another therapeutic strategy in the reconstructive surgical armamentarium, which bears special consideration when dealing with severely disfigured burned patients. The aim of this review is to describe the basics of face composite tissue allotransplantation and give an overview of some of the cases performed until now, with special attention paid to debating the pros and cons of its applicability in burn patients.

Conventional and novel approaches to immunosuppression

Immunosuppressive therapy has contributed significantly to improved survival after solid organ transplantation. Nevertheless, treatment-related adverse events and persistently high risk of chronic graft rejection remain major obstacles to long-term survival after lung transplantation. The development of new agents, refinements in techniques to monitor immunosuppression, and enhanced understanding of transplant immunobiology are essential for further improvements in outcome. In this article, conventional immunosuppressive regimens, novel approaches to preventing graft rejection, and investigational agents for solid organ transplantation are reviewed.

Feasibility, reproducibility, risks and benefits of face transplantation: a prospective study of outcomes

Composite tissue allotransplantations can be indicated when autologous transfers fail to restore human appearance. We report the reproducibility, difficulties, serious adverse events and outcomes of our patients. Five patients were included in a registered clinical research protocol after thorough screenings assessed by an independent expert committee systematically discussing the alternative options. One patient suffered from plexiform neurofibromas, two from third degree burns and two from gunshot injuries. They were included on a national waiting list with a dedicated face procurement procedure. Transplants were harvested from heart beating brain-dead donors before other tissues and organs. Induction immunosuppressive therapy included antithymocyte globulins, steroids, mycophenolate mophetil and tacrolimus. Maintenance therapy included the last three ones associated with extracorporeal-photopheresis. Four patients were transplanted with 7- to 38-month follow-up. One could not due to multiple panel reactive antibodies after 18 months on waiting list. Acute cellular rejections were controlled by conventional treatment. Opportunistic infections affected all patients and lead one patient to die two month after the transplantation. Voluntary facial activity appeared from 3 to 5 month. Face transplantation has been reproducible under conventional immunosuppression. Major improvements in facial aesthetic and function allowed patients to recover social relations and improved their quality of life.

The Combination of Immunosuppressive Drugs with 8-Methoxypsoralen and Ultraviolet a Light Modulates the Myeloid-Derived Dendritic Cell Function

The functional properties of myeloid dendritic cells (DCs) differ, depending on microenvironmental factors as well as on their stage of maturation. The main approaches for the selective enhancement of the tolerogenic properties of DCs include the induction of a pharmacological arrest of the DCs maturation and the genetical engineering of DCs expressing immunosuppressive molecules. Several immunosuppressive/anti-inflammatory agents have been discovered that potentially inhibit DC maturation and immunogenicity. Photopheresis (ECP) is an immunomodulatory therapy in which leucocytes are exposed to 8-methoxypsoralen (8-MOP) and ultraviolet (UV) A radiation (PUVA). The combination of ECP with immunosuppressive agents has demonstrated efficacy in the management of transplanted patients by reducing either the incidence of organ rejection or the pharmacological toxicity. In particular, we have observed in hepatitis C virus (HCV)-positive patients that the same combination has reduced the immunosuppressive burden and improved sustainability and efficacy of pre-emptive antiviral therapy after liver transplantation. Therefore, in our work we investigated the in vitro effects of PUVA, combined with immunosuppressive drugs (IDs), on both in vitro human DC generation and maturation, in order to contribute to understanding the immunological mechanisms underlying this pharmacological combination. Monocyte PUVA-treatment was performed by using an in vitro experimental protocol that we previously described. PUVA-treated or -untreated highly purified CD14+ cells were incubated with the association of the immunosuppressive drugs, used in the management of liver transplantation, at two different concentrations, in the presence of IL-4 and GM-CSF. The treatment with IDs at the highest concentration (corresponding to that used in clinical practice), alone or in association with PUVA, induced an immunosuppressive effect, by impairing both DC generation and maturation. Neither immunosuppressive drugs at the lowest concentration nor their combination with PUVA affected myeloid DC generation, but modified DC functions, strengthening the induction of a tolerogenic pattern. As this ID concentration was arbitrarily chosen, further experiments could highlight whether lower concentrations than those used in clinical practice would elicit the same effect on DCs and potentially improve their functional properties. This work describes an original experimental approach exploring the in vitro mechanism of action of the combined procedure of PUVA with immunosuppressive drugs, used in liver transplantation, on DCs generation and function. Our results contribute to the knowledge of the mechanisms of action of this combined procedure on DCs, suggesting useful therapeutic implications for the in vivo therapy.

Apoptotic cell-based therapies against transplant rejection: role of recipient's dendritic cells

One of the ultimate goals in transplantation is to develop novel therapeutic methods for induction of donor-specific tolerance to reduce the side effects caused by the generalized immunosuppression associated to the currently used pharmacologic regimens. Interaction or phagocytosis of cells in early apoptosis exerts potent anti-inflammatory and immunosuppressive effects on antigen (Ag)-presenting cells (APC) like dendritic cells (DC) and macrophages. This observation led to the idea that apoptotic cell-based therapies could be employed to deliver donor-Ag in combination with regulatory signals to recipient’s APC as therapeutic approach to restrain the anti-donor response. This review describes the multiple mechanisms by which apoptotic cells down-modulate the immuno-stimulatory and pro-inflammatory functions of DC and macrophages, and the role of the interaction between apoptotic cells and APC in self-tolerance and in apoptotic cell-based therapies to prevent/treat allograft rejection and graft-versus-host disease in murine experimental systems and in humans. It also explores the role that in vivo-generated apoptotic cells could have in the beneficial effects of extracorporeal photopheresis, donor-specific transfusion, and tolerogenic DC-based therapies in transplantation.

Rapid generation of maturationally synchronized human dendritic cells: contribution to the clinical efficacy of extracorporeal photochemotherapy

Extracorporeal photochemotherapy (ECP) is widely used to treat cutaneous T-cell lymphoma, graft-versus-host disease, and allografted organ rejection. Its clinical and experimental efficacy in cancer immunotherapy and autoreactive disorders suggests a novel mechanism. This study reveals that ECP induces a high percentage of processed monocytes to enter the antigen-presenting dendritic cell (DC) differentiation pathway, within a single day, without added cytokines, as determined by enhanced expression of relevant genes. The resulting DCs are capable of processing and presentation of exogenous and endogenous antigen and are largely maturationally synchronized, as assessed by the level of expression of costimulatory surface molecules. Principal component analysis of the ECP-induced monocyte transcriptome reveals that activation or suppression of more than 1100 genes produces a reproducible distinctive molecular signature, common to ECP-processed monocytes from normal subjects, and those from patients. Because ECP induces normal monocytes to enter the DC differentiation pathway, this phenomenon is independent of disease state. The efficiency with which ECP stimulates new functional DCs supports the possibility that these cells participate prominently in the clinical successes of the treatment. Appropriately modified by future advances, ECP may potentially offer a general source of therapeutic DCs.

The world's experience with facial transplantation: what have we learned thus far?

The objective of this review article is to summarize the published details and media citations for all seven face transplants performed to date to point out deficiencies in those reports so as to provide the basis for examining where the field of face transplantation stands, and to act as a stimulus to enhance the quality of future reports and functional outcomes. Overall long-term function of facial alloflaps has been reported satisfactorily in all seven cases. Sensory recovery ranges between 3 and 6 months, and acceptable motor recovery ranges between 9 and 12 months. The risks and benefits of facial composite tissue allotransplantation, which involves mandatory lifelong immunosuppression analogous to kidney transplants, should be deliberated by each institution's multidisciplinary face transplant team. Face transplantation has been shown thus far to be a viable option in some patients suffering severe facial deficits which are not amenable to modern-day reconstructive technique.

Living related hemi-face skin transplant using radial forearm free flap for a xeroderma pigmentosa patient: early outcome

Introduction

Xeroderma pigmentosa (XP) is a hereditary disease characterized by deficient repair of DNA damage that occurred on exposure of the skin to ultraviolet irradiation. The affected children have a propensity to develop multiple skin cancers mainly in the face and eventually die before the age of 20.

Hypothesis

Allograft replacement of facial skin by a healthy skin from normal person might decrease the incidence of skin cancer development, the number of surgical procedures, and eventually might improve the survival of these miserable patients.

Methods

As Cadaveric organs are unavailable in our country. After approval from the ethical committee, confirmed agreement of the donor and the patient's guardian, a radial forearm free flap was transplanted from an ABO compatible mother to her 5 year old daughter with XP. The mother had an older daughter died from the same disease at the age of 14. The flap replaced skin of the hemi face that developed precancerous lesions. The girl was kept on adjusted doses of immunosuppressive drugs.

Results

The flap survived, wounds healed uneventfully. The flap developed a reddish spot one and half month following transplant where baseline skin biopsy was taken. In the fifth months the girl presented with bad non salvageable rejection that ended up loosing the flap. On long term follow up, the girl started to develop skin lesion on the virgin half of the face. Our early cosmetic result replacing half of the facial skin was very promising. In addition the girl did not develop skin lesions in the operated site.

Conclusion

Our early cosmetic result was very promising. In addition to this, the girl did not develop skin lesions in the operated side of the face