Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells

The central nervous system (CNS) is comprised of the brain and spinal cord and is enveloped by the meninges, membranous layers serving as a barrier ...

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice

Cerebrospinal fluid (CSF), a fluid found in the brain and the spinal cord, is of great importance to both basic and clinical science. The analysis of the ...

Geisel School of Medicine & Dartmouth-Hitchcock Medical Center

Dartmouth-Hitchcock Medical Center

Teriflunomide is an oral therapy approved for the treatment of relapsing remitting multiple sclerosis (MS), showing both anti-inflammatory and antiviral properties. Currently, it is uncertain whether one or both of these properties may explain teriflunomide's beneficial effect in MS. Thus, to learn more about its mechanisms of action, we evaluated the effect of teriflunomide in the Theiler's encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) model, which is both a viral infection and an excellent model of the progressive disability of MS. We assessed the effects of the treatment on central nervous system (CNS) viral load, intrathecal immune response, and progressive neurological disability in mice intracranially infected with TMEV. In the TMEV-IDD model, we showed that teriflunomide has both anti-inflammatory and antiviral properties, but there seemed to be no impact on disability progression and intrathecal antibody production. Notably, benefits in TMEV-IDD were mostly mediated by effects on various cytokines produced in the CNS. Perhaps the most interesting result of the study has been teriflunomide's antiviral activity in the CNS, indicating it may have a role as an antiviral prophylactic and therapeutic compound for CNS viral infections.

Treatment of Theiler's virus-induced demyelinating disease with teriflunomide.

We evaluated the effects of pegylated-interferonβ-1a (pegIFNβ) therapy on intrathecal antibody responses, disability progression, and viral load in the CNS in mice infected with the Theiler's virus (TMEV), an animal model of progressive disability in Multiple Sclerosis (MS). The lack of a direct antiviral activity in the CNS, the absence of any effect upon the intrathecal immune response, and the failure to treat disease progression, indicate that the immunomodulatory effects of pegIFNβ-1a likely occur in the systemic circulation rather than within the CNS. These results may be relevant to the relative lack of effect of IFNβ in progressive MS relative to relapsing MS.

Pegylated interferon beta in the treatment of the Theiler's murine encephalomyelitis virus mouse model of multiple sclerosis.

The mechanisms driving multiple sclerosis (MS), the most common cause of non-traumatic disability in young adults, remain unknown despite extensive research. Especially puzzling are the underlying molecular processes behind the two major disease patterns of MS: relapsing-remitting and progressive. The relapsing-remitting course is exemplified by acute inflammatory attacks, whereas progressive MS is characterized by neurodegeneration on a background of mild-moderate inflammation. The molecular and cellular features differentiating the two patterns are still unclear, and the role of inflammation during progressive disease is a subject of active debate.

Differential neuro-immune patterns in two clinically relevant murine models of multiple sclerosis.

Persistent central nervous system (CNS) inflammation, as seen in chronic infections or inflammatory demyelinating diseases such as Multiple Sclerosis (MS), results in the accumulation of various B cell subsets in the CNS, including naïve, activated, memory B cells (Bmem), and antibody secreting cells (ASC). However, factors driving heterogeneous B cell subset accumulation and antibody (Ab) production in the CNS compartment, including the contribution of ectopic lymphoid follicles (ELF), during chronic CNS inflammation remain unclear and is a major gap in our understanding of neuroinflammation. We sought to address this gap using the Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) model of progressive MS. In this model, injection of the virus into susceptible mouse strains results in a persistent infection associated with demyelination and progressive disability. During chronic infection, the predominant B cell phenotypes accumulating in the CNS were isotype-switched B cells, including Bmem and ASC with naïve/early activated and transitional B cells present at low frequencies. B cell accumulation in the CNS during chronic TMEV-IDD coincided with intrathecal Ab synthesis in the cerebrospinal fluid (CSF). Mature and isotype-switched B cells predominately localized to the meninges and perivascular space, with IgG isotype-switched B cells frequently accumulating in the parenchymal space. Both mature and isotype-switched B cells and T cells occupied meningeal and perivascular spaces, with minimal evidence for spatial organization typical of ELF mimicking secondary lymphoid organs (SLO). Moreover, immunohistological analysis of immune cell aggregates revealed a lack of SLO-like ELF features, such as cell proliferation, cell death, and germinal center B cell markers. Nonetheless, flow cytometric assessment of B cells within the CNS showed enhanced expression of activation markers, including moderate upregulation of GL7 and expression of the costimulatory molecule CD80. B cell-related chemokines and trophic factors, including APRIL, BAFF, CXCL9, CXCL10, CCL19, and CXCL13, were elevated in the CNS. These results indicate that localization of heterogeneous B cell populations, including activated and isotype-switched B cell phenotypes, to the CNS and intrathecal Ab (ItAb) synthesis can occur independently of SLO-like follicles during chronic inflammatory demyelinating disease.

Krista D. DiSano

Department of Neurology

Geisel School of Medicine & Dartmouth-Hitchcock Medical Center

Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice

Krista D. DiSano

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Neurology

Geisel School of Medicine & Dartmouth-Hitchcock Medical Center

Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice

Department of Neurology