Titin and ryanodine receptor antibodies in myasthenia gravis

  title={Titin and ryanodine receptor antibodies in myasthenia gravis},
  author={Geir Olve Skeie and Johan A. Aarli and Nils Erik Gilhus},
  journal={Acta Neurologica Scandinavica},
Some myasthenia gravis (MG) patients have antibodies against skeletal muscle antigens in addition to the acetylcholine receptor (AChR). Two major antigens for non‐AchR antibodies in MG are the Ca2+ release channel of the sarcoplasmic reticulum, the ryanodine receptor (RyR) and titin, a gigantic filamentous muscle protein essential for muscle structure, function and development. RyR and titin antibodies are found mainly in thymoma MG patients and in a few late‐onset MG patients and correlate… 
Autoantibodies in different forms of myasthenia gravis and in the Lambert-Eaton syndrome.
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  • Biology, Medicine
    Handbook of clinical neurology
  • 2008
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The progress made toward the development of novel sensitive autoantibody detection assays, the identification of new MG autoantigens, and the implications for improved antigen-specific therapeutics are presented.
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This work reviews the different methods for detection of various antibodies involved in MG and their sensitivity and specificity and suggests how to adapt the existing therapies to the requirements of each patient.
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    Expert review of neurotherapeutics
  • 2009
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Three distinct immune mechanisms that describe both the B cell- and autoantibody-mediated pathogenesis of Myasthenia gravis are highlighted by comparing AChR and MuSK MG subtypes.
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Polygenic disease associations in thymomatous myasthenia gravis.
Specific combinations of allelic variants individually associated with MG synergize in predisposing to thymomatous MG and MG with titin antibodies, which seems to be the most important determinant of disease.
Compromised fidelity of B‐cell tolerance checkpoints in AChR and MuSK myasthenia gravis
One aspect not previously described is whether defects in central and peripheral tolerance checkpoints, which allow autoreactive B cells to accumulate in the naive repertoire, are found in both or either form of MG.
Myasthenia gravis-specific aberrant neuromuscular gene expression by medullary thymic epithelial cells in thymoma
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Ryanodine receptor antibodies in myasthenia gravis: Epitope mapping and effect on calcium release in vitro
The data suggest that the Ry1 sequence defined by residues 799–1172 is involved in the regulation of Ry1 function, and that this regulation could be functionally affected in vivo in patients with myasthenia gravis.
Striational autoantibodies in myasthenia gravis patients recognize I-band titin epitopes
Ryanodine receptor antibodies are associated with severe myasthenia gravis
The presence of RyR‐antibodies in thymoma patients is associated with a more severe disease and can be used as a prognostic marker.
Myasthenia gravis sera containing antiryanodine receptor antibodies inhibit binding of [3H]‐ryanodine to sacroplasmic reticulum
Results show that RyR antibodies in MG patients have high affinity for the RyR, and that the binding of antibodies probably affects calcium release from SR by locking theRyR ion channel in a closed position.
Ryanodine receptor antibodies related to severity of thymoma associated myasthenia gravis.
The presence of circulating RyR antibodies seems to be associated with a severe form of thymoma associated myasthenia gravis, which is a calcium release channel involved in the mechanism of excitation-contraction coupling in striations.
Anti-ryanodine receptor antibodies and FK506 in myasthenia gravis
In a preliminary open trial with FK506, immunosuppressant and enhancer of RyR-related sarcoplasmic calcium release, the authors observed the sustained benefits in anti-RyR-positive MG patients.
Muscle autoantibodies in subgroups of myasthenia gravis patients
No single muscle antibody assay can predict a thymoma, and a combination of several antibody assays is preferred, although RyR antibody testing alone showed 70% sensitivity and specificity forThymoma MG.
Spontaneous thymoma rat as a model for myasthenic weakness caused by anti‐ryanodine receptor antibodies
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Ryanodine receptor autoantibodies in myasthenia gravis patients with a thymoma
Sera from patients with myasthenia gravis and a thymoma had IgG autoantibodies to the calcium release channel of the sarcoplasmic reticulum (the ryanodine receptor), which plays a crucial role in the mechanism of excitation‐contraction coupling in striated muscle.
Titin antibodies in patients with late onset myasthenia gravis: clinical correlations.
The presence of circulating titin antibodies in late-onset non-thymoma MG patients indicates a more severe disease.