Exosome-Based Diagnosis and Treatment of Neurological Diseases: A Review of Promise and Challenges in Clinical Translation
Vesicles as clues to disease and participants in the spread of pathology
Exosomes are attracting attention as candidate diagnostic markers and therapeutic delivery vehicles for neurodegenerative diseases, but challenges such as production standardization and safety validation remain before clinical use. A review published in the international journal Biomedicine & Pharmacotherapy summarizes exosome biology, disease-specific biomarker candidates, therapeutic strategies, and development limitations. It does not report a new clinical trial demonstrating diagnostic performance or treatment benefit in patients.
Exosomes are nanoscale extracellular vesicles that carry proteins, lipids, messenger RNA, and noncoding RNA and reflect the state of their cells of origin. Their potential to cross physiological barriers, including the blood–brain barrier, is another reason for interest in central nervous system disease research. However, the possibility of crossing a barrier does not by itself guarantee the efficiency or safety of delivering a particular therapeutic agent to the brain.
The review covers Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and prion diseases. In these conditions, exosomes reflect pathological changes while also contributing to the spread of misfolded proteins and neuroinflammatory signals. This makes it necessary to consider both the properties researchers hope to use for diagnosis and treatment and their role in spreading pathology.
Identifying biomarkers through cellular origin and cargo
The authors emphasize differences among exosomes derived from neurons, astrocytes, and microglia. They explain that cargo and functional effects differ across diseases depending on the cell of origin. Identifying which cell produced a vesicle and what it carries is therefore central to evaluating its association with disease.
Disease-related molecules covered in the review include amyloid beta, tau, alpha-synuclein, myelin proteins, prion protein, and regulatory microRNAs. These are targets of biomarker research; their inclusion in the list does not mean they are validated markers suitable for clinical testing.
The review examines microfluidic isolation, single-vesicle analysis, and multi-omics analysis that examines multiple types of molecular information together. The authors explain that these technologies accelerate biomarker discovery. However, the provided abstract gives no sensitivity or specificity figures or numerical comparisons with existing tests. This material alone does not establish how much the accuracy of early diagnosis has improved.
Potential of therapeutic delivery strategies and outstanding validation
For treatment, the review discusses strategies using stem cell-derived exosomes and vesicles with engineered surfaces. These approaches involve loading cargo such as microRNAs intended for neuroprotection, small molecules, and gene-editing materials. The abstract introduces these strategies but does not present clinical outcomes demonstrating precise delivery to damaged neural circuits, promotion of regeneration, or reduced adverse effects.
The challenges to clinical translation are also specific. The authors point to the need for large-scale production and manufacturing standardization, as well as insufficient characterization of pharmacokinetic and pharmacodynamic properties—the movement and actions of these vesicles in the body—in preclinical models. The potential for immune responses and safety problems at sites other than the intended target also remains. The review further identifies the lack of regulatory guidance tailored to extracellular vesicle medicines as a challenge.
Connecting the diagnostic and therapeutic potential of exosomes to medical practice requires closing the gap between candidate discovery and demonstration of clinical utility. This review outlines both the possibilities and the conditions that need to be validated.
Source: Article citation and abstract
Exosomes are nanoscale extracellular vesicles (EVs) that mediate intercellular communication and carry proteins, lipids, mRNAs, and non-coding RNAs reflective of their parental cells. Their biogenesis, molecular composition, and ability to traverse physiological barriers, including the blood-brain barrier, position exosomes as powerful candidates for biomarker development and therapeutic delivery in neurodegenerative diseases (NDDs). In Alzheimer's disease, Parkinson's disease, multiple sclerosis, and prion disorders, exosomes not only mirror pathological processes but actively participate in the propagation of misfolded proteins and neuroinflammatory signals through cell-type-specific vesicle subpopulations. This review synthesises current advances in exosome biology, cargo sorting, release mechanisms, and pathophysiological roles in the central nervous system, with emphasis on how neuron-, astrocyte-, and microglia-derived exosomes diverge in their cargo profiles and functional consequences across diseases. We highlight disease-specific exosomal signatures, including amyloid-β (Aβ), tau, α-synuclein, myelin proteins, prion proteins (PrP) and regulatory microRNAs. We evaluate emerging technologies such as microfluidic isolation, single-vesicle analysis, and multi-omics profiling that are accelerating biomarker discovery, and review exosome-based therapeutic strategies, including native stem cell-derived exosomes and surface-engineered vesicles loaded with neuroprotective miRNAs, small molecules, and gene-editing cargo. We address critical unmet challenges in translating these approaches to the clinic, including scalable and standardised production, incomplete pharmacokinetic /pharmacodynamic characterisation in preclinical models, immunogenicity and off-target safety concerns, and the absence of specific regulatory guidance for EV drug products. Together, these insights highlight the transformative potential of exosomes as both precision diagnostic tools and diseas
In diagnostic development, researchers can explore exosomes carrying disease-related proteins or microRNAs as candidate markers and design studies comparing differences by cell of origin. Using them for patient diagnosis or monitoring disease course requires separate validation of test accuracy and clinical utility. In therapeutic development, delivering neuroprotective agents in vesicles is a strategy under consideration. Development requires standardizing manufacturing conditions and evaluating movement and activity in the body, immune responses, and safety outside the intended target. This review summarizes the issues to address when moving candidate technologies into clinical use, providing a basis for assessing research design and development priorities.