Background Antimyelin-associated glycoprotein (MAG) polyneuropathy is a slowly progressive distal form of mixed motor-sensory polyneuropathy that is scarcely responsive to conventional immunosuppressive therapy. Rituximab, a B-cell depleting antibody, is a promising therapeutic choice for anti-MAG polyneuropathy, and the evaluation of factors, such as B-cell-activating factor (BAFF), that control B-cell homeostasis is important to understand how this drug works.
Methods Using an ELISA method, the authors measured serum BAFF concentrations in 23 patients with anti-MAG polyneuropathy, before and after rituximab therapy, in 20 neurological controls and in 14 healthy subjects. The patients were followed up over a mean period of 38±12 months and categorised as responders/non-responders, and, between the responders, as relapsing/non-relapsing.
Results Pretherapy serum BAFF concentrations in non-responders were higher than in responders (cut-off 1665 pg/ml; sensitivity 71.4%; specificity 93.7%; likelihood ratio 11.4), with the highest post-therapy increases in responders. In the responders who relapsed, relapses occurred when serum BAFF concentrations returned to baseline values, 1–2 years after blood B-cell reappearance.
Conclusions Before and during therapy, measurements of serum BAFF in rituximab-treated patients with anti-MAG polyneuropathy may help predict the response to the therapy. The findings in this study also provide information about rituximab-induced modifications on B-cell homeostatic regulation.
- Autoimmune disorders of the nervous system
- B-cell-activating factor
- biological markers
- myelin associated glycoprotein
Statistics from Altmetric.com
Funding This work was supported by grant RC2009 (Italian ‘Ministero della Salute’) to Neurological Institute Mondino.
Competing interests SJ has received a Fellowship from the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and research grants from Merck Serono and Bayer Schering Healthcare.
Patient consent Obtained.
Ethics approval Ethics approval was provided by the Department of Neuroscience, Ophtalmology and Genetics, Genova, Italy.
Provenance and peer review Not commissioned; externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.