Choroid plexus emerges as key player in multiple sclerosis progression, systematic review finds

Multiple sclerosis is a chronic neuroinflammatory disease of the central nervous system, characterised by demyelination, neurodegeneration and progressive disability accumulation. Although autoimmune mechanisms are considered central to its pathogenesis, the precise pathways in which they occur remain incompletely understood. A systematic review now pulls together the experimental and human evidence pointing to a structure that rarely features in public discussion of the disease: the choroid plexus. According to the review, published in Fluids and Barriers of the CNS, the choroid plexus has emerged as an important mediator in multiple sclerosis, acting not merely as a passive gateway but as an active participant in the neuroinflammatory processes that shape the disease’s course.

The review’s authors, led by Alexandra Carvalho with contributions from Joana Guimarães, Ana Mendanha Falcão and Ricardo Soares-dos-Reis, set out to synthesise the fragmented literature on how this tissue contributes to disease onset and progression. Their conclusion is that the choroid plexus plays a multifaceted role through mechanisms that include immune infiltration, barrier disruption and genomic changes. Imaging studies of people with multiple sclerosis have demonstrated enlargement and inflammation of the choroid plexus, and these changes correlate with disease activity and progression. That correlation, the authors stress, does not by itself establish causation; they explicitly call for further investigation to clarify the temporal and causal relationships between the mechanisms already described.

The review positions the choroid plexus as a permissive barrier for immune cell entry, but also as a dynamic neuroimmune interface that participates in signalling pathways, shaping immune infiltration and neuroinflammation.

The evidence base for these claims comes from two complementary streams. Human imaging studies have demonstrated enlargement and inflammation of the choroid plexus in multiple sclerosis brains, and these changes correlate with disease activity and progression. Alongside these observations, animal research has probed the cellular and molecular behaviour of the choroid plexus under experimental conditions that model aspects of the disease. The review’s scope is deliberately preclinical: it covers studies in human samples and animal research rather than clinical trials of interventions, which means the findings describe mechanisms and associations rather than tested treatments.

One of the review’s most candid observations is that the molecular and cellular mechanisms underlying choroid plexus involvement in multiple sclerosis remain poorly characterised, with fragmented evidence across the current literature. The authors suggest that further investigation into temporal and causal relationships would motivate research towards novel multiple sclerosis treatment strategies, though they stop short of proposing specific interventions.

The review's authors note that the molecular and cellular mechanisms underlying choroid plexus involvement in multiple sclerosis remain poorly characterised, with fragmented evidence across the current literature. Imaging studies have demonstrated enlargement and inflammation of the choroid plexus in multiple sclerosis brains, and these changes correlate with disease activity and progression. Published open access on 31 October 2026, the review concludes that the choroid plexus plays a multifaceted role in multiple sclerosis pathophysiology and progression through mechanisms that include immune infiltration, barrier disruption and genomic changes, and calls for further investigation to establish temporal and causal relationships between these mechanisms.

Subject of Research: The role of the choroid plexus in the pathophysiology and progression of multiple sclerosis

Article Title: The role of the choroid plexus in the pathophysiology and progression of multiple sclerosis: a systematic review of preclinical studies in human samples and animal research

Article References: Carvalho, A., Guimarães, J., Falcão, A. M., & Soares-dos-Reis, R. (2026). The role of the choroid plexus in the pathophysiology and progression of multiple sclerosis: a systematic review of preclinical studies in human samples and animal research. Fluids and Barriers of the CNS. https://doi.org/10.1186/s12987-026-00895-2

Image Credits: AI Generated

DOI: 10.1186/s12987-026-00895-2

Keywords: multiple sclerosis, choroid plexus, neuroinflammation, systematic review, blood-cerebrospinal fluid barrier, immune cell infiltration, demyelination, neurodegeneration, preclinical studies, human samples, role, choroid