Photopheresis for the treatment of lupus erythematosus. Preliminary observations

Extracorporeal Photopheresis in Dermatological Diseases

Extracorporeal photopheresis (ECP) is an apheresis procedure that is conventionally used as a first-line treatment for cutaneous and leukemic subtypes of T-cell lymphoma, such as Sezary's syndrome and mycosis fungoides. Over the past three decades, its immunotherapeutic properties have been tested on a variety of autoimmune conditions, including many dermatologic diseases. There is ample evidence of ECP's ability to modify leukocytes and alter cytokine production for certain dermatologic diseases that have been refractory to first-line treatments, such as atopic dermatitis. However, the evidence on the efficacy of ECP for the treatment of these dermatologic diseases is unclear and/or lacks sufficient evidence. The purpose of this paper is to review the literature on the utilization and clinical efficacy of ECP in the treatment of several [autoimmune] dermatologic diseases and discuss its applications, guidelines, recommendations, and future implementation for dermatologic diseases.

Effect of xanthotoxin (8-methoxypsoralen) on the anticonvulsant activity of classical antiepileptic drugs against maximal electroshock-induced seizures in mice

The effects of xanthotoxin (8-methoxypsoralen) on the anticonvulsant activity of four classical antiepileptic drugs (carbamazepine, phenobarbital, phenytoin and valproate) were studied in the mouse maximal electroshock seizure model. Tonic hind limb extension (seizure activity) was evoked in adult male albino Swiss mice by a current (25 mA, 500 V, 50 Hz, 0.2 s stimulus duration) delivered via auricular electrodes. Total brain concentrations of antiepileptic drugs were measured by fluorescence polarization immunoassay to ascertain any pharmacokinetic contribution to the observed anticonvulsant effects. Results indicate that xanthotoxin (50 and 100 mg/kg, i.p.) significantly potentiated the anticonvulsant activity of carbamazepine against maximal electroshock-induced seizures (P<0.05 and P<0.001, respectively). Similarly, xanthotoxin (100 mg/kg, i.p.) markedly enhanced the anticonvulsant action of valproate in the maximal electroshock seizure test (P<0.001). In contrast, xanthotoxin (100 mg/kg, i.p.) did not affect the protective action of phenobarbital and phenytoin against maximal electroshock-induced seizures in mice. Moreover, xanthotoxin (100 mg/kg, i.p.) significantly increased total brain concentrations of carbamazepine (P<0.001) and valproate (P<0.05), but not those of phenytoin and phenobarbital, indicating pharmacokinetic nature of interactions between drugs. In conclusion, the combinations of xanthotoxin with carbamazepine and valproate, despite their beneficial effects in terms of seizure suppression in mice, were probably due to a pharmacokinetic increase in total brain concentrations of these antiepileptic drugs in experimental animals.

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

Pyrrolo[2,3-h]quinolinones: a new ring system with potent photoantiproliferative activity

A new class of compounds, the pyrrolo[2,3-h]quinolin-2-ones, nitrogen isosters of the angular furocoumarin Angelicin, was synthesized with the aim of obtaining new photochemotherapeutic agents with increased antiproliferative activity and lower undesired toxic effects than the lead compound. Two synthetic pathways were approached to allow the isolation both of the dihydroderivatives 10-17 and of the aromatic ring system 23. Compounds 10-17 showed a remarkable phototoxicity and a great UVA dose dependence reaching IC(50) values at submicromolar level. Intracellular localization of these compounds has been evaluated by means of fluorescence microscopy using tetramethylrhodamine methyl ester and acridine orange, which are specific fluorescent probes for mitochondria and lysosomes, respectively. A weak co-staining was observed with mitochondrial stain, whereas a specific localization in lysosomes was observed. Studies directed to elucidate the mode of action of this series of compounds revealed that they do not intercalate with DNA and do not induce photodamage to the macromolecule. On the contrary, they induce significative photodamage to lipids and proteins.

The use of extracorporeal photopheresis for allograft rejection in liver transplant recipients

BACKGROUND

Originally introduced for cutaneous T-cell lymphomas and autoimmune diseases, extracorporeal photopheresis (ECP) has been proven effective to reverse allograft rejection. The aim of the present work was to show the results of a single-center experience with ECP for the treatment of biopsy-proven rejection in selected liver transplant (LT) recipients.

PATIENTS AND METHODS

A retrospective review of five LT patients (M:F=4:1; median age 51 years) undergoing ECP for biopsy-proven allograft rejection between January 1996 and December 2003. In this period 476 LT were performed on 441 patients.

RESULTS

The indications for LT were three cases of HCV-related cirrhosis, complicated by hepatocellular carcinoma in two; one HBV-HDV-alcoholic cirrhosis; and one fulminant HBV hepatitis. All patients received calcineurin-inhibitor (CNI)-based immunosuppression with induction using anti-IL2R monoclonal antibodies. Indications for ECP were: ductopenic rejection in one patient with HCV recurrence; steroid-resistant acute rejection in two; acute rejection in a major ABO-mismatched liver graft; and one acute rejection in a patient with a proven allergy to steroids. The median interval from LT to inception of ECP was 43 days. The median number of ECP sessions per patient was 20. During the course of ECP, two patients tested positive for CMV antigenemia, associated in one case with bacterial pneumonia. All patients tolerated ECP and there were no procedure-related complications. At a median follow-up of 7.9 months after start of ECP, neither rejection relapses nor HCV/HBV recurrences have been observed. Three patients are off ECP with complete reversal and low-dose immunosuppression. Two patients are still receiving ECP with full-dose immunosuppression: one has achieved normal liver function but ECP is indicated due to a major ABO-incompatible liver graft, while the other patient's liver functions have not yet returned to baseline values.

Selective immmunotherapy through extracorporeal photochemotherapy: yesterday, today, and tomorrow

ECP's extensive clinical record, as well as a considerable improvement in the understanding of the mechanism that underlies its efficacy, opens potential novel strategies for the treatment of cancer, GVHD, transplant rejection, and autoimmunity. The low side effect profile of this therapy has made it a more attractive treatment consideration than current conventional chemotherapeutic and immunosuppressive medications. As the mechanism of action of ECP is more fully elucidated and clinical studies are completed, the role of ECP in modern therapeutics of CTCL and other malignancies, as well as in the treatment of other T-cell mediated diseases, will be become clearer.

Psoralen and UVA light: an in vitro investigation of multiple immunological mechanisms underlying the immunosuppression induction in allograft rejection

Photopheresis (ECP) is a novel immunomodulatory therapy effectively used to treat several T-cell-mediated diseases and to reverse allograft rejection after organ transplantation. It consists of infusion of UVA-irradiated autologous leukocytes collected by apheresis and extracorporeally incubated with 8-methoxypsoralen (8-MOP). In this study we explored the potential immunological events for therapeutic efficacy of photopheresis in preventing allograft rejection by evaluating in vitro the combined effects of 8-MOP and UVA (PUVA) on multiple immunological parameters, such as induction of apoptosis, production of soluble mediators, and expression of cell antigens. Peripheral blood mononuclear cells (PBMCs) obtained from healthy subjects were treated with 8-MOP and UVA at the same doses as those clinically used in ECP. We demonstrate that PUVA treatment induced leukocyte hyporesponsiveness and a decrease in expression of co-stimulatory and adhesion molecules as well as of cytokine levels. Additionally, PUVA treatment induced apoptosis in both mononuclear cells (possibly through the Fas/FasL system and/or the CD38 pathway) and purified monocytes. In conclusion, our work focuses attention on the initial phase of immune response and identifies some new targets of therapy (e.g., costimulatory molecules) able to trigger final effects underlying therapeutic efficacy of photopheresis.

Photopheresis and autoimmune diseases

Although several case reports and case series suggest efficacy for photopheresis in the treatment of autoimmune diseases, few controlled studies have been conducted to test this hypothesis. After a decade of interest, multiple case reports, open trials, and one controlled study, the role of photopheresis in autoimmune disease remains to be established. Controlled multi-center trials in rheumatoid arthritis, SLE, and scleroderma may be costly but are clearly necessary for proper evaluation of this therapy.

Apheresis for lupus erythematosus

Indications for the use of apheresis technologies in managing lupus erythematosus have undergone numerous conceptual changes since the procedure was automated in the 1960s and first attempted for systemic lupus erythematosus (SLE) in 1974. Once thought to be a promising treatment for a variety of aspects of SLE, apheresis has been relegated to occupying a few important niches as an adjunct in managing the disorder. This article will review the history, physiology and rationale of apheresis pertaining to SLE. A focused critical review of pertinent literature is presented, along with specific recommendations relating to the place of apheresis in the lupus therapeutic spectrum.

Normal oxidative activity and chemotaxis of circulating neutrophils in patients treated with photopheresis

In photopheresis peripheral leukocytes are exposed to photoactivated 8-methoxypsoralen in an extra-corporeal flow system. The present study was performed to characterize the effect of photopheresis upon the function of peripheral circulating neutrophils. Superoxide generating capacity and chemotactic ability of peripheral circulating neutrophils were tested in seven patients immediately before and after treatment with photopheresis. Superoxide generation stimulated by phorbol-12-myristate-13-acetate and N-formyl-methionyl-leucyl-phenylalanine (fMLP) and fMLP-induced chemotaxis were found not to be influenced by photopheresis. We conclude that circulating neutrophils obtained from patients treated with photopheresis possess normal superoxide-generating capacity and chemotactic ability.