Granulocyte macrophage colony-stimulating factor treatment of a patient in myasthenic crisis: Effects on regulatory T cells

Department of Neurology and Rehabilitation, University of Illinois Medical Center, 912 South Wood Street, 855N, M/C 796, Chicago, Illinois 60612, USA.
Muscle & Nerve (Impact Factor: 2.28). 09/2012; 46(3):449-53. DOI: 10.1002/mus.23488
Source: PubMed


In this study we describe a patient with a prolonged myasthenic crisis refractory to conventional immunomodulatory therapy who was treated with GM-CSF (granulocyte macrophage colony-stimulating factor, sargramostim).
T-regulatory cell (Treg) suppressive function and Foxp3 expression were evaluated before and after treatment with GM-CSF.
Treatment with GM-CSF was associated with clinical improvement, expansion in the circulating numbers of Foxp3(+) cells, increase in Foxp3 expression levels in Tregs, early improvement in Treg suppressive capacity for AChR-α-induced T-cell proliferation, and subsequent enhancement in Treg suppression of polyclonal T-cell proliferation.
Although definitive conclusions cannot be drawn from a single case, the correlation with similar findings in GM-CSF-treated animals with experimental autoimmune myasthenia gravis suggests further exploration of the effects of GM-CSF in myasthenia gravis should be studied in a clinical trial setting.

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