University of Colorado School of Medicine
Cell & Developmental Biology

Author Of 1 Presentation

Neuroprotection, Regeneration and/or Remyelination Oral Presentation

YI01.05 - BTK signaling regulates real-time microglial dynamics and prevents demyelination in a novel in vivo model of antibody-mediated cortical demyelination

Speakers
Presentation Number
YI01.05
Presentation Topic
Neuroprotection, Regeneration and/or Remyelination
Lecture Time
11:48 - 12:00

Abstract

Background

Multiple Sclerosis (MS) is an immune-mediated disease of the central nervous system (CNS) characterized by cortical demyelinating lesions containing activated microglia and phagocytic macrophages. The complex dynamics between microglia and oligodendrocytes during demyelination remain to be established. Bruton’s Tyrosine Kinase (BTK) is a key regulator of microglial phagocytosis; however, it is unclear whether modulation of BTK directly affects immune-mediated demyelination.

Objectives

To visualize and manipulate in vivo microglia-oligodendrocyte interactions during cortical myelin loss and repair.

Methods

We developed a novel in vivo model of immune-mediated cortical demyelination through the application of recombinant antibodies derived from MS patients and human complement (MSrAb+huC’) onto the cortical surface. We characterized cellular interactions in real-time via longitudinal in vivo two-photon microscopy of myelinating oligodendrocytes and microglia in transgenic mice.

Results

We found that MSrAb+huC’ application resulted in robust demyelination that recapitulated MS pathology. Microglia rapidly engulfed myelin sheaths following the application of MSrAb+huC’, and subsequently increased their density, accumulating around heavily affected oligodendrocytes. Oral administration of a brain-penetrant BTK-inhibitor prior to the application of MSrAb+huC’ drastically altered microglia dynamics in the 72 hours post-surgery, notably by diminishing engulfment morphology and density changes. Moreover, BTK-inhibition prevented the loss of oligodendrocytes.

Conclusions

Inhibition of BTK signaling alters microglia-oligodendrocyte interactions and limits complement-dependent antibody-mediated demyelination. These findings provide a novel context to define glial interactions during immune-regulated demyelination and outline a crucial role for microglia in driving myelin loss.

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Presenter Of 1 Presentation

Neuroprotection, Regeneration and/or Remyelination Oral Presentation

YI01.05 - BTK signaling regulates real-time microglial dynamics and prevents demyelination in a novel in vivo model of antibody-mediated cortical demyelination

Speakers
Presentation Number
YI01.05
Presentation Topic
Neuroprotection, Regeneration and/or Remyelination
Lecture Time
11:48 - 12:00

Abstract

Background

Multiple Sclerosis (MS) is an immune-mediated disease of the central nervous system (CNS) characterized by cortical demyelinating lesions containing activated microglia and phagocytic macrophages. The complex dynamics between microglia and oligodendrocytes during demyelination remain to be established. Bruton’s Tyrosine Kinase (BTK) is a key regulator of microglial phagocytosis; however, it is unclear whether modulation of BTK directly affects immune-mediated demyelination.

Objectives

To visualize and manipulate in vivo microglia-oligodendrocyte interactions during cortical myelin loss and repair.

Methods

We developed a novel in vivo model of immune-mediated cortical demyelination through the application of recombinant antibodies derived from MS patients and human complement (MSrAb+huC’) onto the cortical surface. We characterized cellular interactions in real-time via longitudinal in vivo two-photon microscopy of myelinating oligodendrocytes and microglia in transgenic mice.

Results

We found that MSrAb+huC’ application resulted in robust demyelination that recapitulated MS pathology. Microglia rapidly engulfed myelin sheaths following the application of MSrAb+huC’, and subsequently increased their density, accumulating around heavily affected oligodendrocytes. Oral administration of a brain-penetrant BTK-inhibitor prior to the application of MSrAb+huC’ drastically altered microglia dynamics in the 72 hours post-surgery, notably by diminishing engulfment morphology and density changes. Moreover, BTK-inhibition prevented the loss of oligodendrocytes.

Conclusions

Inhibition of BTK signaling alters microglia-oligodendrocyte interactions and limits complement-dependent antibody-mediated demyelination. These findings provide a novel context to define glial interactions during immune-regulated demyelination and outline a crucial role for microglia in driving myelin loss.

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