This study looked at identifying people at risk of developing progressive multifocal leucoencephalopathy (PML) during natalizumab treatment. The study included 289 people with MS, 224 of which were treated with natalizumab (18-80 months) while 21 received other immune-modulatory treatments and 28 were untreated.
The research group had 16 samples from natalizumab PML patients, of which eight had given blood prior to the diagnosis of PML. They found that the percentage of l-selectin-expressing CD4+ T cells was significantly lower in people treated long-term with natalizumab when compared with people with MS not receiving natalizumab treatment or healthy controls. A very low percentage was highly correlated with the risk of developing PML in the group with available pre-PML samples when compared with non-PML natalizumab-treated people with MS. Therefore, this demonstrates that the cell-based assessment of the percentage of l-selectin-expressing CD4+ T cells has the possibility of providing a biomarker for individual PML risk assessment.
Authors: Schwab N, Schneider-Hohendorf T
Source: Neurology. 2013 Aug 7. [Epub ahead of print]
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