Azathioprine therapy of "autoimmune" diseases

Treatment of autoimmunity: The impact of disease-modifying therapies in multiple sclerosis and comorbid autoimmune disorders

More than 10 disease-modifying therapies (DMT) are approved by the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) for the treatment of multiple sclerosis (MS) and new therapeutic options are on the horizon. Due to different underlying therapeutic mechanisms, a more individualized selection of DMTs in MS is possible, taking into account the patient's current situation. Therefore, concomitant treatment of various comorbid conditions, including autoimmune mediated disorders such as rheumatoid arthritis, should be considered in MS patients. Because the pathomechanisms of autoimmunity partially overlap, DMT could also treat concomitant inflammatory diseases and simplify the patient's treatment. In contrast, the exacerbation and even new occurrence of several autoimmune diseases have been reported as a result of immunomodulatory treatment of MS. To simplify treatment and avoid disease exacerbation, knowledge of the beneficial and adverse effects of DMT in other autoimmune disorders is critical. Therefore, we conducted a literature search and described the beneficial and adverse effects of approved and currently studied DMT in a large number of comorbid autoimmune diseases, including rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel diseases, cutaneous disorders including psoriasis, Sjögren´s syndrome, systemic lupus erythematosus, systemic vasculitis, autoimmune hepatitis, and ocular autoimmune disorders. Our review aims to facilitate the selection of an appropriate DMT in patients with MS and comorbid autoimmune diseases.

Mechanism-Driven Read-Across of Chemical Hepatotoxicants Based on Chemical Structures and Biological Data

Hepatotoxicity is a leading cause of attrition in the drug development process. Traditional preclinical and clinical studies to evaluate hepatotoxicity liabilities are expensive and time consuming. With the advent of critical advancements in high-throughput screening, there has been a rapid accumulation of in vitro toxicity data available to inform the risk assessment of new pharmaceuticals and chemicals. To this end, we curated and merged all available in vivo hepatotoxicity data obtained from the literature and public resources, which yielded a comprehensive database of 4089 compounds that includes hepatotoxicity classifications. After dividing the original database of chemicals into modeling and test sets, PubChem assay data were automatically extracted using an in-house data mining tool and clustered based on relationships between structural fragments and cellular responses in in vitro assays. The resultant PubChem assay clusters were further investigated. During the cross-validation procedure, the biological data obtained from several assay clusters exhibited high predictivity of hepatotoxicity and these assays were selected to evaluate the test set compounds. The read-across results indicated that if a new compound contained specific identified chemical fragments (ie, Molecular Initiating Event) and showed active responses in the relevant selected PubChem assays, there was potential for the chemical to be hepatotoxic in vivo. Furthermore, several mechanisms that might contribute to toxicity were derived from the modeling results including alterations in nuclear receptor signaling and inhibition of DNA repair. This modeling strategy can be further applied to the investigation of other complex chemical toxicity phenomena (eg, developmental and reproductive toxicities) as well as drug efficacy.

The Use of Human Mesenchymal Stem Cells as Therapeutic Agents for the in vivo Treatment of Immune-Related Diseases: A Systematic Review

Background: One of the greatest challenges for medicine is to find a safe and effective treatment for immune-related diseases. However, due to the low efficacy of the treatment available and the occurrence of serious adverse effects, many groups are currently searching for alternatives to the traditional therapy. In this regard, the use of human mesenchymal stem cells (hMSCs) represents a great promise for the treatment of a variety of immune-related diseases due to their potent immunomodulatory properties. The main objective of this study is, therefore, to present and summarize, through a systematic review of the literature, in vivo studies in which the efficacy of the administration of hMSCs for the treatment of immune-related diseases was evaluated. Methods: The article search was conducted in PubMed/MEDLINE, Scopus and Web of Science databases. Original research articles assessing the therapeutic potential of hMSCs administration for the in vivo treatment immune-related diseases, published from 1984 to December 2017, were selected and evaluated. Results: A total of 132 manuscripts formed the basis of this systematic review. Most of the studies analyzed reported positive results after hMSCs administration. Clinical effects commonly observed include an increase in the survival rates and a reduction in the severity and incidence of the immune-related diseases studied. In addition, hMSCs administration resulted in an inhibition in the proliferation and activation of CD19⁺ B cells, CD4⁺ Th1 and Th17 cells, CD8⁺ T cells, NK cells, macrophages, monocytes, and neutrophils. The clonal expansion of both Bregs and Tregs cells, however, was stimulated. Administration of hMSCs also resulted in a reduction in the levels of pro-inflammatory cytokines such as IFN-γ, TNF-α, IL-1, IL-2, IL-12, and IL-17 and in an increase in the levels of immunoregulatory cytokines such as IL-4, IL-10, and IL-13. Conclusions: The results obtained in this study open new avenues for the treatment of immune-related diseases through the administration of hMSCs and emphasize the importance of the conduction of further studies in this area.

Purine Synthesis Inhibitors, 6-thioguanine and Azathioprine: Forgotten Treatment Options in Psoriasis and Psoriatic Arthritis

Background

The thiopurine drugs azathioprine and 6-thioguanine have been shown to induce significant clinical improvement in patients with moderate to severe psoriasis and/or psoriatic arthritis.

Objective

The aim of this paper is to present a comprehensive review of the available literature concerning the off-label role of thiopurine drugs in the treatment of psoriasis and psoriatic arthritis.

Methods

Studies published with English abstracts between 1960 and 2008 identified in MEDLINE and PubMed with the keywords purine synthesis inhibitors, thiopurine, 6-thioguanine, azathioprine, psoriasis and psoriatic arthritis were reviewed.

Results

Although 6-thioguanine and azathioprine have shown significant efficacy, their side effect profiles have discouraged their use for moderate to severe psoriasis.

Conclusion

For treatment of psoriasis and psoriatic arthritis, purine synthesis inhibitors should not be forgotten. They represent an entirely different option and provide an alternative therapy, especially for difficult cases.

Au-ACRAMTU-PEt3 Alters Redox Balance To Inhibit T Cell Proliferation and Function

Although T cells play a critical role in protection from viruses, bacteria, and tumors, they also cause autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. Unwanted T cell responses during organ transplant, graft-versus-host disease, and allergies are also major clinical problems. Although drugs are available to suppress unwanted immune responses, they have limited efficacy with serious side effects. Thus, new therapeutics limiting T cell activation, proliferation, and function can make an immediate clinical impact. To identify new suppressors of lymphocyte activation, proliferation, and function, we examined the immunosuppressive activity of gold(I) analogs of platinum-acridine antitumor agents. We found that the gold complex Au-ACRAMTU-PEt3 is a potent suppressor of murine and human T cell activation. Preincubation with Au-ACRAMTU-PEt3 suppresses the proliferation of CD4(+) and CD8(+) T cells at a similar concentration as pharmaceutical grade cyclosporine A. Au-ACRAMTU-PEt3 pretreatment decreases the production of IFN-γ, TNF-α, IL-2, and IL-17 by human and murine CD4(+) and CD8(+) T cells. When mice were treated with Au-ACRAMTU-PEt3 during viral infection, the expansion of virus-specific CD8(+) T cells was decreased 10-fold and viral load was elevated. Taken together, these results demonstrate that Au-ACRAMTU-PEt3 has potent immunosuppressive activity that could be used to suppress immune responses during transplantation and autoimmunity.

Successful rituximab treatment of refractory hemophagocytic lymphohistiocytosis and autoimmune hemolytic anemia associated with systemic lupus erythematosus

High-dose steroids, immunosuppressants such as cyclophosphamide and cyclosporine, and high-dose intravenous immunoglobulin have all been used to control hemophagocytic lymphohistiocytosis (HLH) or autoimmune hemolytic anemia (AIHA) associated with systemic lupus erythematosus (SLE); however, some patients are refractory to treatment. Rituximab has successfully resolved many of the refractory manifestations of SLE. Here, we report a case of HLH and AIHA associated with SLE that was refractory or intolerable to conventional therapy, but was successfully treated with rituximab.

How I treat autoimmune hemolytic anemias in adults

Autoimmune hemolytic anemia is a heterogeneous disease with respect to the type of the antibody involved and the absence or presence of an underlying condition. Treatment decisions should be based on careful diagnostic evaluation. Primary warm antibody autoimmune hemolytic anemias respond well to steroids, but most patients remain steroid-dependent, and many require second-line treatment. Currently, splenectomy can be regarded as the most effective and best-evaluated second-line therapy, but there are still only limited data on long-term efficacy and adverse effects. The monoclonal anti-CD20 antibody rituximab is another second-line therapy with documented short-term efficacy, but there is limited information on long-term efficacy and side effects. The efficacy of immunosuppressants is poorly evaluated. Primary cold antibody autoimmune hemolytic anemias respond well to rituximab but are resistant to steroids and splenectomy. The most common causes of secondary autoimmune hemolytic anemias are malignancies, immune diseases, or drugs. They may be treated in a way similar to primary autoimmune hemolytic anemias, by immunosuppressants or by treatment of the underlying disease.

Azathioprine in dermatology: The past, the present, and the future

For several decades, dermatologists have utilized azathioprine to treat numerous debilitating skin diseases. This synthetic purine analog is derived from 6-mercaptopurine. It is thought to act by disrupting nucleic acid synthesis and has recently been found to interfere with T-cell activation. The most recognized uses of azathioprine in dermatology are for immunobullous diseases, generalized eczematous disorders, and photodermatoses. In this comprehensive review, the authors present recent advancements in the understanding of azathioprine and address aspects not covered in prior reviews. They (1) summarize the history of azathioprine; (2) discuss metabolism, integrating information from recent publications; (3) review the mechanism of action with attention paid to the activities of azathioprine not mediated by its 6-mercaptopurine metabolites and review new data about inhibition by azathioprine of the CD28 signal transduction pathway; (4) thoroughly examine thiopurine s-methyltransferase genetics, its clinical relevance, and interethnic variations; (5) review prior uses of azathioprine in the field of dermatology and grade the level of evidence; (6) discuss the use of azathioprine in pregnancy and pediatrics; review (7) key drug interactions and (8) adverse effects; (9) suggest a dosing and monitoring approach different from prior recommendations; and (10) explore the future of azathioprine, focusing on laboratory considerations and therapeutic application.

Drug eruption caused by azathioprine: value of using the drug-induced lymphocytes stimulation test for diagnosis

Azathioprine (AZA) is an immunosuppressant commonly used for organ transplantation and autoimmune diseases. Allergic side effects of AZA are rare, and reported allergic skin eruptions from AZA are very limited in Japan. We report AZA-induced drug eruption that developed in two cases of systemic scleroderma with polymyositis. One case presented with Stevens-Johnson syndrome, and the other had systemic papular erythema. The stimulation indices of the drug-induced lymphocyte stimulation test (DLST) for AZA in these two patients were as high as 2,180% and 430%, respectively, but those of healthy volunteers were under 120% without nonspecific suppression of lymphocyte proliferation. Other drugs used simultaneously were ruled out by patch and challenge tests. The challenge test for Stevens-Johnson syndrome type drug allergy is very risky. DLST is a good diagnostic tool for AZA allergy, especially for severe drug allergy cases.

Azathioprine and methotrexate in multiple sclerosis

Evidence for the effectiveness of immunosuppressive agents in MS is scanty. There are few good quality trials; most have methodological limitations, such as a small sample size and short duration. Moreover, there is no consistency in treatment regimes, patient groups or outcome measures and the clinical benefits remain unclear. Although azathioprine appears to reduce the relapse rate in MS patients, its effect on disability progression has not been demonstrated. Methotrexate may alter the course of disease favourably in patients with progressive MS, but the evidence is again sparse.

Old and new drugs used in rheumatoid arthritis: a historical perspective. Part 1: the older drugs

Rheumatoid arthritis is the paradigmatic immune-mediated inflammatory arthropathy and may be of comparatively recent, New World origin. Apart from the symptom-relieving nonsteroidal anti-inflammatory drugs, whose natural congeners have been in use since antiquity for musculoskeletal pain and inflammation, only a dozen drugs or drug classes--the disease-modifying antirheumatic drugs--are currently in common use in rheumatoid arthritis. Development of these drugs has been a notable achievement of the 20th century. Some were developed serendipitously (glucocorticoids, antimalarials), some were the product of faulty reasoning (gold, D-penicillamine), and others were applied for plausible reasons but whose mechanism remains unproven (sulfasalazine, methotrexate, minocycline). A minority were originally applied on the basis of actions that remain germane to the pathophysiology of rheumatoid arthritis as currently understood (azathioprine, cyclosporine, leflunomide, infliximab, etanercept). Among the latter are the more recently introduced and effective agents. The practical use of these drugs is determined by efficacy-toxicity considerations, which have also driven the recent development of the cyclooxygenase-2-selective nonsteroidal anti-inflammatory drugs.

Treatment of pyoderma gangrenosum

Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection.

Systemic immunosuppressive therapy and the occurrence of malignancy in patients with ocular inflammatory disease

PURPOSE

To compare the occurrence of malignancy in patients with severe ocular inflammatory disease treated with systemic corticosteroids alone or with systemic immunosuppressive drugs with or without systemic corticosteroids.

METHODS

The clinical records of 543 patients with ocular inflammatory disease treated with systemic corticosteroids and/or immunosuppressive chemotherapy were reviewed in a retrospective cohort study. Characteristics of patients treated with corticosteroids alone were compared with characteristics of patients treated with immunosuppressive agents with or without preceding corticosteroid treatment. The rates of malignancy after initiation of drug therapy were compared using an exact test for incidence rate data.

RESULTS

Compared with patients treated with corticosteroids alone, patients treated with immunosuppressants with or without corticosteroid treatment were older and had more severe systemic disease. During a total of 1261 person-years of follow-up, a malignancy developed in five patients. The rate of malignancy in the immunosuppressant group (4 malignancies during 968 person-years of follow-up) was not significantly different from the rate in the corticosteroids alone group (1 malignancy during 293 person-years of follow-up) (P > 0.90, exact test for incidence rate data).

CONCLUSION

These findings do not support the hypothesis of an increased risk of malignancy in patients with severe ocular inflammatory disease who are treated with systemic immunosuppressive agents compared with patients treated with systemic corticosteroids.

Treatment of autoimmune uveitis

The number of effective drugs for the treatment of autoimmune uveitis has greatly increased over the past 40 years. Many patients previously condemned to blindness can now be successfully treated with new immunosuppressive agents. New targets of the immune system, such as cell adhesion molecules, may offer novel therapeutic approaches for the treatment of inflammatory disease. However, since the catholicon for uveitis is not yet available, the search for new antiinflammatory therapy continues.

Ground glasslike hepatocytes produced by glycogen-membrane complexes ("glycogen bodies")

A 54-year-old man developed liver disease 11 months after renal transplantation. Liver biopsy demonstrated hepatitis with numerous periodic acid-Schiff-positive, diastase-sensitive ground glass inclusions in parenchymal cells. Electron microscopy revealed that the inclusions consisted of parallel arrays of smooth surfaced cisternae separated by glycogen rosettes ("glycogen bodies"). The differential diagnosis of ground glass hepatocytes, the occurrence of glycogen bodies, and the possible etiological factors in the patient's liver disease are discussed.

Immunosuppressive drugs in immune and inflammatory ocular disease

Advances in immunology, particularly ocular immunology, have been accompanied by the emergence of safer, more specific immunosuppressive drugs, notably, cyclophosphamide, chlorambucil, methotrexate, azathioprine, cyclosporine A, bromocriptine, dapsone, and colchicine. These drugs have become an important, and often essential, part of the ophthalmologist's armamentarium against inflammatory and immune-mediated ocular diseases. In order to better acquaint the ophthalmologist with the properties of the most commonly used immunosuppressive drugs, we review the literature and relate our own experience with these agents.

Azathioprine hypersensitivity. Case report and review of the literature

Fever in a transplant recipient is an important sign of graft rejection or infection. Rarely, fever may result from an immunosuppressive agent used to prevent graft rejection. A case of fever, rigors, arthralgias, and myalgias is reported in a cardiac transplant recipient in whom azathioprine therapy was recently begun. These findings resolved on discontinuation of the azathioprine, recurred on rechallenge, and were most consistent with a hypersensitivity reaction. The clinical spectrum of reported azathioprine hypersensitivity reactions is reviewed.

Drug-induced cholestasis

Intrahepatic cholestasis, defined as arrested bile flow, mimics extrahepatic obstruction in its biochemical, clinical and morphological features. It may be due to hepatocyte lesions of which there are three types, termed canalicular, hepatocanalicular and hepatocellular, respectively; or it may be due to ductal lesions at the level of the cholangiole or portal or septal ducts. Defective bile flow due to hepatic lesions reflects abnormal modification of the ductular bile. Defective formation of canalicular bile may involve bile acid-dependent or independent flow. It appears to result most importantly from defective secretion of bile acid-dependent flow secondary to defective uptake from sinusoidal blood, defective transcellular transport and defective secretion; or from regurgitation of secreted bile via leaky tight junctions. An independent defect in bile acid-independent flow is less clear. Defective flow of bile along the canaliculus may reflect increased viscosity and impaired canalicular contractility secondary to injury of the pericanalicular microfibrillar network. Impaired flow beyond the canaliculus may result from ductal injury. Sites of lesions that contribute to cholestasis include the sinusoidal and canalicular plasma membrane, the pericanalicular network and the tight junction and, less certainly, microtubules and microfilaments and Golgi apparatus. A number of drugs that lead to cholestasis have been found to lead to injury at one or more of these sites. Other agents (alpha-naphthylisothiocyanate, methylenedianiline, contaminated rapeseed oil, paraquat) lead to ductal injury resulting in cholestasis. Reports of inspissated casts in ductules (benoxaprofen jaundice) and injury to the major excretory tree (5-fluorouridine after hepatic artery infusion) have led to other forms of ductal cholestasis. Most instances of drug-induced cholestasis present as acute, transient illness, although important chronic forms also occur. The clinical features include the reflection of the cholestasis (pruritus, jaundice), systemic manifestations and extrahepatic organ involvement. While nearly all classes of medicinal agents include some that can lead to cholestasis, there are differences among the various categories. Phenothiazines and related antipsychotic and 'tranquillizer' drugs characteristically lead to cholestatic hepatic injury. The tricyclic antidepressants may lead to cholestatic or hepatocellular injury.(ABSTRACT TRUNCATED AT 400 WORDS)

Azathioprine hypersensitivity manifesting as acute focal hepatocellular necrosis

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Cytotoxic agents for use in dermatology. I

There are indications for the use of cytotoxic drugs in some dermatologic diseases. These drugs may be lifesaving for patients with diseases such as pemphigus, lymphomas, and vasculitis or they may merely offer an improved quality of life for patients who have diseases such as psoriasis, progressive systemic sclerosis, or sarcoidosis. In either set of circumstances, in the properly monitored patient cytotoxic drugs may be used safely and effectively, offering very few problems for the patient or the therapist. The dermatologist who is interested in offering his/her patients the best medical care possible will wish to become proficient in the use of cytotoxic drugs, just as he/she is proficient in the use of the tetracyclines, systemic corticosteroids, and other powerful, but useful, agents.

Hypersensitivity and jaundice due to azathioprine

A patient is described who suffered hypersenitivity reactions (anorexia, nausea and vomiting) as well as cholestatic jaundice from therapy with azathioprine. Evidence is given that the 2 reactions were mediated by different portions of the azathioprine molecule.

The association of chronic active hepatitis with pyoderma gangrenosum

This report deals with a 25-year-old man with chronic active hepatitis and cirrhosis who developed the rare complication of pyoderma gangrenosum which improved rapidly following the commencement of prednisolone.

Immunosuppressive therapy of idiopathic thrombocytopenic purpura

The autoimmune nature of idiopathic thrombocytopenic purpura, as currently defined, is well established. Manipulations of the immune apparatus aimed at abating this deviant immunologic state may be one mode of approach to the therapy of this disease. Several cytotoxic compounds are capable of inhibiting the primary and secondary immune response to experimentally injected antigens in animals and man. Their beneficial role in the treatment of an autoimmune lupus-like syndrome in NZB mice24 is well documented. In human autoimmune disease, efficacy of the drugs is still to be established. The mechanisms by which immunosuppressive agents effect therapeutic response, and, in particular, whether this action is linked to suppression of immune reactivity needs clarification. Although preliminary analysis of the efficacy of immunosuppressive drugs in idiopathic thrombocytopenic purpura is encouraging, their therapeutic role has not superseded that of conventional management with steroids and splenectomy. Carefully controlled randomized clinical trials are now necessary so that more rational use of these agents can be recommended in future reports.

Clinical use of immunosuppressive drugs: part II

In haematological diseases, insufficient data has been accumulated to evaluate the efficacy of immunosuppressive drug treatment in patients with erythroid aplasia or sideroblastic anaemia. Cyclophosphamide may be efficacious in inhibiting circulating anticoagulants in patients who need continued replacement of clotting factors. Azathioprine, 6-mercaptopurine, cyclophosphamide and vincristine have been used successfully in treating patients with idiopathic thrombocytopenic purpura, and some patients with auto-immune haemolytic anaemia may benefit from the addition of purine analogues. However, the use of immunosuppressive therapy seems to accelerate the presence of haematological malignancies in patients with macroglobulinaemia. In gastro-intestinal diseases, uncontrolled studies have shown nitrogen mustard, 6-mercaptopurine and azathioprine to be of modest benefit to patients with ulcerative colitis and Crohn's disease. In a controlled trial azathioprine plus prednisone proved more effective than prednisone alone in sustaining remission in patients with Crohn's disease. In patients with either chronic active hepatitis or primary biliary cirrhosis, however, there seems to be no benefit from immunosuppressive therapy for primary treatment of these diseases. Cyclophosphamide, azathioprine and methotrexate have all been used with some success in treating patient with uveitis, and in a controlled trial cytarabine has been shown to be beneficial to patients with herpes ophthalmicus. However, no benefit has been shown to patients with the eye changes of Graves' disease with either azathioprine or methotrexate. Patients with Paget's disease appear to be helped by mithramycin. Cyclophosphamide, chlorambucil and azathioprine are ineffective in treating patients with multiple sclerosis. 6-Mercaptopurine, azathioprine, methotrexate and cyclophosphamide have all produced some benefit in patients with myasthenia gravis, and some patients with idiopathic pulmonary haemosiderosis have responded to azathioprine, 6-mercaptopurine and cyclophosphamide. Alkylating agents have proved useful in treating some patients with asthma and in treating frequent relapsers among children with the nephrotic syndrome. In adults with membrano-proliferative glomerulonephritis some patients have responded to combination therapy with cyclophosphamide, azathioprine and corticosteroids. Immunosuppressive therapy is also indicated in prolonging graft survivals in patients receiving organ transplants. Drug toxicities of immunosuppressive agents are discussed. Their long-term effects, including mutagenic potential, have as yet not been fully elucidated.

Idiopathic thrombocytopenic purpura in children

Idiopathic thrombocytopenic purpura in children 10 years of age or younger was observed to have a more favorable prognosis than in older children. Corticosteroid therapy in children judged to be at increased risk of serious hemorrhage resulted in a significantly greater number of patients with an early increase in platelets than was noted in a control group. All patients with chronic disease who responded to administration of a corticosteroid initially and then relapsed had some response to a subsequent course of therapy, although none had a sustained remission. In such patients, splenectomy was a more effective therapeutic measure than treatment with either a corticosteroid or a cytotoxic agent.

Treatment of psoriasis with azathioprine

Azathioprine treatment benefited 19 (66%) out of 29 patients suffering from severe psoriasis. Haematological complications were not troublesome and results of biochemical liver function tests remained normal. Minimal cholestasis was seen in two cases and portal fibrosis of a reversible degree in eight. Liver biopsies should be undertaken at regular intervals if azathioprine therapy is continued so that structural liver damage may be detected at an early and reversible stage.