Immunomodulation of autoimmune and inflammatory diseases with intravenous immune globulin.

Polymyositis and dermatomyositis belong to the group of inflammatory muscle diseases. This chapter deals only with the “idiopathic” polymyositis and dermatomyositis syndromes; parasitic, bacterial, spirochetal, and viral infectious myopathies will not be discussed. For recent reviews of the general subject, the reader may wish to refer to Banker and Engel (1986), Dalakas (1991, 1992), Engel (1992)

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(03)14368-1.pdf

Polymyositis and Dermatomyositis

The molecular basis for the anti-inflammatory property of intravenous gamma globulin (IVIG) was investigated in a murine model of immune thrombocytopenia. Administration of clinically protective doses of intact antibody or monomeric Fc fragments to wild-type or Fcgamma receptor-humanized mice prevented platelet consumption triggered by a pathogenic autoantibody. The inhibitory Fc receptor, FcgammaRIIB, was required for protection, because disruption either by genetic deletion or with a blocking monoclonal antibody reversed the therapeutic effect of IVIG. Protection was associated with the ability of IVIG administration to induce surface expression of FcgammaRIIB on splenic macrophages. Modulation of inhibitory signaling is thus a potent therapeutic strategy for attenuating autoantibody-triggered inflammatory diseases.

https://science.sciencemag.org/content/sci/291/5503/484.full.pdf

Anti-inflammatory Activity of IVIG Mediated Through the Inhibitory Fc Receptor

Background Dermatomyositis is a clinically distinct myopathy characterized by rash and a complement-mediated microangiopathy that results in the destruction of muscle fibers. In some patients the condition becomes resistant to therapy and causes severe physical disabilities. Methods We conducted a double-blind, placebo-controlled study of 15 patients (age, 18 to 55 years) with biopsy-proved, treatment-resistant dermatomyositis. The patients continued to receive prednisone (mean daily dose, 25 mg) and were randomly assigned to receive one infusion of immune globulin (2 g per kilogram of body weight) or placebo per month for three months, with the option of crossing over to the alternative therapy for three more months. Clinical response was gauged by assessing muscle strength, neuromuscular symptoms, and changes in the rash. Changes in immune-mediated muscle abnormalities were determined by repeated muscle biopsies. Results The eight patients assigned to immune globulin had a significant improvement in sco...

A Controlled Trial of High-Dose Intravenous Immune Globulin Infusions as Treatment for Dermatomyositis

Preface Part I. Overview of Pathologic and Pathogenic Comparison Between Sporadic Inclusion-Body Myositis and Hereditary Inclusion-Body Myopathies: 1. Newest approaches to diagnosis and pathogenesis of sporadic inclusion-body myositis and hereditary inclusion-body myopathies, including molecular-pathologic similarities to Alzheimer disease Part II. Historical Perspective: 2: Evolving concepts of inclusion-body myositis Part III. Sporadic Inclusion-Body Myositis - Clinical and Diagnostic Considerations: 3: Sporadic inclusion-body myositis: Clinical and laboratory features and diagnostic criteria 4: Inclusion-body myositis: natural history 5: Uncommon clinico-pathological forms of sporadic inclusion-body myositis: Report of four cases 6: Inclusion-body myositis: pathological changes 7: Unusual pathological forms of inclusion-body myositis, and neuromuscular disorders with IBM-like changes 8: Electrophysiological findings in inclusion-body myositis 9: Genetic factors in sporadic inclusion-body myositis Part IV. Hereditary Inclusion-Body Myopathies - Clinical and Diagnostic Considerations: 10: Hereditary inclusion-body myopathy in Jews of Persian origin: Clinical and laboratory data 11. Hereditary inclusion-body myopathy (h-IBM) with quadriceps sparing: epidemiology and genetics 12: Familial autosomal-recessive inclusion-body myositis with asymptomatic leukoencephalopathy 13: Welander distal myopathy - clinical, pathophysiological, and molecular aspects 14. Tibial muscular dystrophy - clinical, genetic, and morphological characteristics 15. Distal myopathy with rimmed vacuoles, inclusion-body myositis and related disorders in Japan 16. Inclusion-body myopathies 17. Is the muscle fiber in inclusion body-myositis an antigen-presenting cell of an innocent bystander? 18. Viruses, immunodeficiency and inclusion-body myositis 19. Myonuclear abnormalities may play a central role in the pathogenesis of muscle fiber damage in inclusion-body myositis 20. Nuclear degeneration and rimmed vacuole formation in neuromuscular disorders 21. Mitochondrial alterations in sporadic inclusion-body myositis 22. mtDNA analysis in muscle of patients with sporadic inclusion-body myopathy Part V. Treatment: 23. Evaluation of treatment for sporadic inclusion-body myositis 24. Personal experience in treating sporadic inclusion-body myositis Subject index.

Inclusion body myositis and myopathies.

Eleven patients with demyelinating polyneuropathy associated with monoclonal IgM antibodies were randomized to receive IVIg or placebo, monthly, for 3 months in a double-blind study. After a washout period, they crossed over to the alternate therapy. Response was gauged by evaluating muscle strength, sensation, and neuromuscular symptoms at baseline, after 3 months, and at treatment's end. After IVIg therapy, the strength improved in only 2 of 11 patients, by 28 and 38.5 points from baseline, and declined after placebo. In 1 other patient, the sensory score improved by 13 points. Antibody titers to MAG/SGPG or gangliosides did not appreciably change. We conclude that IVIg has only a modest benefit to not more than 18% of patients with IgM paraproteinemic demyelinating neuropathy.

A controlled study of intravenous immunoglobulin in demyelinating neuropathy with IgM gammopathy.

We report the treatment of four patients with inclusion-body myositis (IBM) and severe slowly progressive weakness using high-dose intravenous immunoglobulin (IVIg). After two monthly infusions, the strength of the proximal and less atrophic muscle groups improved or normalized in three of the four patients. The improvement lasted from 2 to 4 months. Intravenous immunoglobulin is the first treatment modality to improve the strength of some muscles in patients with this disabling inflammatory myopathy. In view of the high cost of IVIg, the unexpected but encouraging results from this pilot study warrant a controlled trial.

Treatment of inclusion‐body myositis with high‐dose intravenous immunoglobulin

Patients on long-term zidovudine (AZT) therapy experience muscle fatigue and weakness attributed to AZT-induced mitochondrial toxicity in skeletal muscle. To determine if the clinico-pathological abnormalities in these patients correspond to abnormal muscle energy metabolism, we used 31P in vivo magnetic resonance spectroscopy to follow phosphorylated metabolites during exercise. We studied 19 normal volunteers, 6 HIV-positive patients never treated with AZT, and 9 HIV-positive patients who had been treated with AZT for a mean period of 33 mo (range 12-48 mo) and had muscle biopsy-proven AZT-myopathy with abnormal mitochondria. Changes in phosphocreatine, ATP, and intracellular pH in the gastrocnemius muscle were followed during a graded steady state exercise protocol, and the recovery of phosphocreatine was followed on cessation of exercise. We found that graded steady state exercise produced a greater depletion of muscle phosphocreatine levels in the AZT-treated patients, compared to either HIV-positive patients who were not treated with AZT or normal controls. No differences in the effects of steady state exercise on muscle phosphocreatine levels were observed between the control group and the HIV-positive patients who had not been treated with AZT. The results suggest that the effect of AZT on muscle energy metabolism is significant, and similar to the effect observed in patients with known mitochondrial myopathies. Using a well-known model for control of mitochondrial metabolism, the observed differences in steady state phosphocreatine levels during exercise suggest that AZT treatment decreases the maximal work output and the maximal rate of muscle ATP synthesis.

/pdf/metabolic-abnormalities-in-skeletal-muscle-of-patients-zikztcu13s.pdf

Metabolic abnormalities in skeletal muscle of patients receiving zidovudine therapy observed by 31P in vivo magnetic resonance spectroscopy.

The majority of autoimmune neuromuscular diseases fall into three groups: 1) The autoimmune neuropathies, which include the acute inflammatory demyelinating polyneuropathy (Guillain-Barre syndrome), the chronic inflammatory demyelinating polyneuropathy, the paraproteinemic polyneuropathies, and the anti-GM1-associated motor neuropathies with conduction block; 2) the inflammatory myopathies, which include the dermatomyositis and polymyositis complex; and 3) the autoimmune neuromuscular junction defects, which include myasthenia gravis, and the Lambert-Eaton myasthenic syndrome. Laboratory and clinical evidence suggests that circulating antibodies or sensitized lymphocytes are operating in the pathogenesis of these conditions. Current immunotherapies include treatment with plasmapheresis, high-dose steroids, or immunosuppressive drugs. Although all of these therapies are effective in a number of patients and for some period of time, they often result in serious side effects that necessitate their discontinuation. The need for safer and more effective therapies in the treatment of these conditions prompted the use of high-dose i.v. immune globulin (IVIG). A number of small trials and a few reports suggest that IVIG is safe and effective in the treatment of patients with autoimmune neuropathies, inflammatory myopathies, and myasthenia gravis unresponsive to conventional therapies. We will present current experience with IVIG in the abovementioned autoimmune neuromuscular diseases, and we will stress the need for long-term controlled studies. The possible immunomodulatory action of IVIG in these conditions will also be discussed.

/pdf/treatment-of-autoimmune-neuromuscular-diseases-with-high-4li018rl3l.pdf

Shawke A. Soueidan

Papers

A Controlled Trial of High-Dose Intravenous Immune Globulin Infusions as Treatment for Dermatomyositis

A controlled study of intravenous immunoglobulin in demyelinating neuropathy with IgM gammopathy.

Treatment of inclusion‐body myositis with high‐dose intravenous immunoglobulin

Metabolic abnormalities in skeletal muscle of patients receiving zidovudine therapy observed by 31P in vivo magnetic resonance spectroscopy.

Treatment of Autoimmune Neuromuscular Diseases with High-Dose Intravenous Immune Globulin