The effects of high dose interferon-β1a on plasma microparticles: Correlation with MRI parameters

Objectives: we previously reported a correlation between levels of microparticles carrying cd31 (pmp cd31+) and disease activity in ms. however,the effects of long term (12 month) treatment with high dose,high frequency interferon-β1a (rebif™) on plasma levels of pmpcd31+,pmpcd146+,and pmpcd54+and mri measures of disease activity have not yet been assessed.methods: during this prospective 1-year study,we used flow cytometry to measure changes in plasma microparticles (pmp) bearing cd31 (pmpcd31+),cd146 (pmpcd146+),and cd54/icam-1 (pmpcd54+) in 16 consecutive patients with relapsing-remitting ms (rrms) before and after 3,6,and 12 months of subcutaneous therapy with interferon-beta1a (44 micrograms,3x weekly). at each visit,clinical exams and expanded disability status scale (edss) scores were recorded.results: plasma levels of pmpcd31+,and pmpcd54+were significantly reduced by treatment with ifn-β1a. pmpcd146+appeared to decrease only at 3 months and did not persist at 6 and 12 months (p = 0.0511). in addition,the decrease in plasma levels of pmpcd31+and pmpcd54+levels at 12 months were associated with a significant decrease in the number and volume of contrast enhancing t1-weigthed lesions.conclusion: our data suggest that serial measurement of plasma microparticles (pmp),particularly in the initial stages of ms (when neuro-inflammatory cascades are more intense),may serve as reliable and reproducible surrogate markers of response to ifn-β1a therapy for ms. in addition,the progressive decline in plasma levels of pmpcd31+and pmpcd54+further supports the concept that ifn-β1a exerts stabilizing effect on the cerebral endothelial cells during pathogenesis of ms. © 2011 lowery-nordberg et al; licensee biomed central ltd.