Preactive lesions in multiple sclerosis.

Curr Opin Neurol

Department of Pathology, VU Medical Center, Amsterdam, The Netherlands.

Published: June 2009

Purpose Of Review: Knowledge of the early pathological changes observed in multiple sclerosis (MS) has advanced by implementation of many improved pathological, biochemical and imaging techniques. This review highlights the accumulating evidence for early pathological changes we term 'preactive lesions', characterized by clusters of activated microglia in otherwise normal-appearing white matter.

Recent Findings: Compelling evidence is accumulating for pathological changes in normal-appearing white matter of MS patients, which occur before the actual development of the active demyelinating lesion. Focal disorder has been documented in normal-appearing white matter of MS months to years before the appearance of gadolinium-enhancing lesions. In these foci, clusters of activated microglia are found in the absence of demyelination and clear leukocyte infiltration, distinguishing them from the traditional demyelinating active and chronic active lesions. Although the events that give rise to preactive lesions are still to be identified, oligodendrocyte abnormalities appear to be crucially involved. Importantly, preactive lesions do not always develop into demyelinating lesions but often appear to resolve without subsequent disorder.

Summary: Preactive lesions in MS represent early stages in the formation of destructive MS lesions. As many of them spontaneously resolve, they are expected to hold important clues to stop the inflammatory process in MS.

Download full-text PDF

Source
http://dx.doi.org/10.1097/WCO.0b013e32832b4c76DOI Listing

Publication Analysis

Top Keywords

preactive lesions
16
pathological changes
12
normal-appearing white
12
multiple sclerosis
8
early pathological
8
clusters activated
8
activated microglia
8
white matter
8
lesions
7
preactive
4

Similar Publications

Does active decompression of odontogenic keratocyst change the histologic diagnosis?

Oral Maxillofac Surg

June 2022

Oral and Maxillofacial Surgery Residency Program, School of Dental Medicine, University of Puerto Rico - Medical Sciences Campus, Paseo Dr. José Celso Barbosa, San Juan, 00921, Puerto Rico.

Aim: The purpose of this study was to compare the histopathologic findings of pre- and post-active decompression of odontogenic keratocyst and to establish if such findings were consistent.

Materials And Methods: A retrospective case series from a group of patients diagnosed with odontogenic keratocyst who underwent active decompression and distraction sugosteogenesis followed by final enucleation was designed and implemented. The dependent variable was changed in histologic diagnosis, as evaluated by an oral and maxillofacial pathologist.

View Article and Find Full Text PDF

Experimental autoimmune encephalomyelitis (EAE) is a model of multiple sclerosis (MS). EAE reflects important histopathological hallmarks, dissemination, and diversity of the disease, but has only moderate reproducibility of clinical and histopathological features. Focal lesions are less frequently observed in EAE than in MS, and can neither be constrained to specific locations nor timed to occur at a pre-specified moment.

View Article and Find Full Text PDF

QUAKING Regulates Microexon Alternative Splicing of the Rho GTPase Pathway and Controls Microglia Homeostasis.

Cell Rep

December 2020

Segal Cancer Center, Lady Davis Institute for Medical Research and Gerald Bronfman Department of Oncology and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, QC H3T1E2, Canada. Electronic address:

The role of RNA binding proteins in regulating the phagocytic and cytokine-releasing functions of microglia is unknown. Here, we show that microglia deficient for the QUAKING (QKI) RNA binding protein have increased proinflammatory cytokine release and defects in processing phagocytosed cargo. Splicing analysis reveals a role for QKI in regulating microexon networks of the Rho GTPase pathway.

View Article and Find Full Text PDF

Regulation of microglial TMEM119 and P2RY12 immunoreactivity in multiple sclerosis white and grey matter lesions is dependent on their inflammatory environment.

Acta Neuropathol Commun

December 2019

Amsterdam UMC, location VUmc, Department of Anatomy and Neurosciences, De Boelelaan, 1108, 1081 HZ, Amsterdam, The Netherlands.

Article Synopsis
  • Multiple Sclerosis (MS) is a leading cause of neurological disability in young adults, marked by immune cell infiltration, damage to nerve sheaths, and loss of nerve fibers.
  • This study investigates the behavior of specific microglia markers (TMEM119 and P2RY12) in grey and white matter MS lesions to better understand their differentiation and immunological status.
  • Findings reveal that white matter lesions have decreased TMEM119 and P2RY12 markers, correlating with lymphocyte activity, while grey matter lesions show no change in these markers, indicating a complex interaction of immune responses in MS pathology.
View Article and Find Full Text PDF

Widespread inflammatory lesions within the central nervous system grey and white matter are major hallmarks of multiple sclerosis. The development of full-blown demyelinating multiple sclerosis lesions might be preceded by preactive lesions which are characterized by focal microglia activation in close spatial relation to apoptotic oligodendrocytes. In this study, we investigated the expression of signaling molecules of oligodendrocytes that might be involved in initial microglia activation during preactive lesion formation.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!