Circulating microRNAs as Biomarkers for B-Cell Depletion Therapy/ Rituximab in Neuromyelitis Optica
Type: Molecular Diagnostics
Neuromyelitis optica (NMO) is a chronic autoimmune disease of the central nervous system (CNS). The main immunological feature of the disease is the presence of autoantibodies to Aquaporin 4 (AQP4+), identified in about 82% of cases. Currently, there are no reliable biomarkers for monitoring treatment response in patients with NMO. A common treatment for NMO is retuximab that can be further optimized based on such predictive markers.
Specific miRNA signatures in whole blood of patients with NMO can be used as biomarkers for therapy response and can potentially reflect the degree of disease activity in the CNS of inflammatory demyelinating disorders.
Total RNA extracted from whole blood of 9 rituximab-responsive NMO patients before, and 6 months following treatment was subjected to small RNAseq analysis. The study included also an additional group of 7 untreated AQP4+ seropositive NMO patients and 15 healthy controls (HCs).
1. 14 miRNA were upregulated and 32 were downregulated significantly in the blood of NMO patients following effective therapy with rituximab (all p<0.05).
2. Expression of 17 miRNAs was significantly higher and of 25 miRNAs was significantly lower in untreated NMO patients compared with HCs (all p<0.05). Following rituximab treatment, the expression levels of 10 of the 17 miRNAs that show increased expression in NMO reverted to the levels seen in HCs. Six of these "normalized" miRNAs are known as brain specific/enriched miRNAs.
Use of biomarkersto further optimize treatment regeme and monitor treatment outcome can be beneficial for companies that have rituximab or products exerting their action in similar mechanism of action to gain access toNMO patients and other neuroinflammtory disorders.