Contributions
Abstract: P971
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 14 Genetics/Epigenetics
Introduction: Multiple sclerosis (MS) is an autoimmune disease of the CNS characterized by inadequate recognition of antigens and an inflammatory immune response mediated by lymphocytes and macrophages. Its pathogenesis is based on the interaction between genetic and environmental factors.
Epigenetic mechanisms can change the expression of genes and may also modulate the response to many environmental factors, thus potentially modifying MS susceptibility. It operates using many mechanisms including DNA methylation, histone modifications and MicroRNAs (miRNAs). In recent years, numerous evidences point to the role of microRNAs controlling immunological processes, including the development and maturation of T and B lymphocytes, presentation of antigens, and cytokine production. They are small RNA sequences that are not translated into proteins, but may interfere with the regulation of coding RNAs. In this context, the differential expression of some miRNAs, and their role in various autoimmune diseases, including MS have been investigated. MicroRNA-155 (miRNA-155) is a multifunctional molecule that plays a crucial role in inflammation.
Objectives: To analyze the expression of circulating miRNA-155 in the serum of Portuguese MS patients.
Methods: The study included 60 MS patients (38 female and 22 male) and 75 healthy controls (HC). RNA extraction from serum was performed using the miRNeasy Serum/Plasma Kit. MiRNA-155 gene expression was detected with a TaqMan® miRNA assay. Relative expression values were calculated using the 2-ΔΔCt method. Differences in ΔCt were evaluated using a two-tailed Student's t-test.
Results: The serum concentration of miRNA-155 was significantly higher in MS patients compared with HC (fold change 4.60; p< 0.0001).
Conclusions: Circulating miRNAs have emerged as potential biomarkers for several human diseases including MS. As far as is known, miRNA-155 is the only miRNA consistently increased in MS brain and spinal cord lesions and in peripheral blood mononuclear cells. In this study miRNA-155 levels were increased in patient's serum which supports the findings of Zhang et al, 2014. These are preliminary results of a national project that intends to study different microRNAs, which are known to be immunologically relevant, in a large cohort of MS patients.
Disclosure: This work was supported by BIEM.
Andreia Bettencourt: nothing to disclose.
Daniela Boleixa: nothing to disclose.
Cláudia Carvalho: nothing to disclose.
Bárbara Leal: nothing to disclose.
Raquel Samões: nothing to disclose.
Ana Paula Sousa: nothing to disclose.
Ernestina Santos: nothing to disclose.
Ana Aires: nothing to disclose.
Joana Guimarães: nothing to disclose.
Maria José Sá: nothing to disclose.
Paulo Pinho e Costa: nothing to disclose.
Berta Martins da Silva: nothing to disclose.
Ana Martins da Silva: nothing to disclose.
Abstract: P971
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 14 Genetics/Epigenetics
Introduction: Multiple sclerosis (MS) is an autoimmune disease of the CNS characterized by inadequate recognition of antigens and an inflammatory immune response mediated by lymphocytes and macrophages. Its pathogenesis is based on the interaction between genetic and environmental factors.
Epigenetic mechanisms can change the expression of genes and may also modulate the response to many environmental factors, thus potentially modifying MS susceptibility. It operates using many mechanisms including DNA methylation, histone modifications and MicroRNAs (miRNAs). In recent years, numerous evidences point to the role of microRNAs controlling immunological processes, including the development and maturation of T and B lymphocytes, presentation of antigens, and cytokine production. They are small RNA sequences that are not translated into proteins, but may interfere with the regulation of coding RNAs. In this context, the differential expression of some miRNAs, and their role in various autoimmune diseases, including MS have been investigated. MicroRNA-155 (miRNA-155) is a multifunctional molecule that plays a crucial role in inflammation.
Objectives: To analyze the expression of circulating miRNA-155 in the serum of Portuguese MS patients.
Methods: The study included 60 MS patients (38 female and 22 male) and 75 healthy controls (HC). RNA extraction from serum was performed using the miRNeasy Serum/Plasma Kit. MiRNA-155 gene expression was detected with a TaqMan® miRNA assay. Relative expression values were calculated using the 2-ΔΔCt method. Differences in ΔCt were evaluated using a two-tailed Student's t-test.
Results: The serum concentration of miRNA-155 was significantly higher in MS patients compared with HC (fold change 4.60; p< 0.0001).
Conclusions: Circulating miRNAs have emerged as potential biomarkers for several human diseases including MS. As far as is known, miRNA-155 is the only miRNA consistently increased in MS brain and spinal cord lesions and in peripheral blood mononuclear cells. In this study miRNA-155 levels were increased in patient's serum which supports the findings of Zhang et al, 2014. These are preliminary results of a national project that intends to study different microRNAs, which are known to be immunologically relevant, in a large cohort of MS patients.
Disclosure: This work was supported by BIEM.
Andreia Bettencourt: nothing to disclose.
Daniela Boleixa: nothing to disclose.
Cláudia Carvalho: nothing to disclose.
Bárbara Leal: nothing to disclose.
Raquel Samões: nothing to disclose.
Ana Paula Sousa: nothing to disclose.
Ernestina Santos: nothing to disclose.
Ana Aires: nothing to disclose.
Joana Guimarães: nothing to disclose.
Maria José Sá: nothing to disclose.
Paulo Pinho e Costa: nothing to disclose.
Berta Martins da Silva: nothing to disclose.
Ana Martins da Silva: nothing to disclose.