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Updated: Apr 29, 2026
Detection of MicroRNAs in Microglia by Real-time PCR in Normal CNS and During Neuroinflammation
Published on: July 23, 2012
Blood miRNA expression pattern is a possible risk marker for natalizumab-associated progressive multifocal
M Muñoz-Culla1, H Irizar1, T Castillo-Triviño2
1Biodonostia Health Research Institute, San Sebastián, SpainSpanish network on Multiple Sclerosis.
Background:
Natalizumab has shown its efficacy in reducing multiple sclerosis (MS) relapses and progression of disability; however, it has been associated with an increased risk of developing progressive multifocal leukoencephalopathy (PML). The differential expression of microRNA (miRNA), the small non-coding RNAs that regulate gene expression, in natalizumab-treated patients has been reported and miRNA have also been described as good candidates for disease biomarkers.
Objective:
To characterize the effect of natalizumab therapy on the miRNA expression pattern and to search for miRNAs that can predict PML on an individual basis.
Methods:
The expression of 754 microRNAs was measured in blood samples from 19 relapsing-remitting MS patients at three time points during natalizumab therapy, using TaqMan OpenArray panels. Two patients included in this study developed PML after more than 2 years of therapy.
Results:
We found that the expression level of three miRNAs (let-7c, miR-125a-5p and miR-642) was affected after 6 months of therapy (t6). Furthermore, we observed a differential expression of another three miRNAs (miR-320, miR-320b and miR-629) between the PML and non-PML groups after 12 months of treatment (t12); and a positive correlation was found between therapy time and the expression of miR-320.
Conclusions:
Natalizumab modified the expression levels of three miRNAs after a 6-month treatment. We suggest miR-320, miR-320b and miR-629 as possible biomarkers for individual PML risk assessment.
Insights
Natalizumab treatment alters microRNA (miRNA) expression in multiple sclerosis patients. Specific miRNAs, including miR-320, may help predict the risk of progressive multifocal leukoencephalopathy (PML).
Area of Science:
- Neuroimmunology
- Molecular Biology
- Biomarker Discovery
Background:
- Natalizumab is effective for multiple sclerosis (MS) but carries a risk of progressive multifocal leukoencephalopathy (PML).
- MicroRNAs (miRNAs) regulate gene expression and have potential as disease biomarkers.
- Previous studies suggest altered miRNA expression in natalizumab-treated patients.
Purpose of the Study:
- To investigate the impact of natalizumab therapy on miRNA expression patterns in MS patients.
- To identify specific miRNAs that can predict an individual's risk of developing PML.
Main Methods:
- Measured the expression of 754 miRNAs in blood samples from 19 relapsing-remitting MS patients.
- Samples were collected at three time points during natalizumab therapy.
- Utilized TaqMan OpenArray panels for miRNA analysis.
Main Results:
- After 6 months of natalizumab therapy, the expression of three miRNAs (let-7c, miR-125a-5p, miR-642) was significantly altered.
- After 12 months, three different miRNAs (miR-320, miR-320b, miR-629) showed differential expression between patients who developed PML and those who did not.
- A positive correlation was observed between therapy duration and miR-320 expression.
Conclusions:
- Natalizumab therapy modifies the expression levels of specific miRNAs within 6 months.
- The miRNAs miR-320, miR-320b, and miR-629 are proposed as potential biomarkers for assessing individual PML risk in natalizumab-treated MS patients.
