New Breakthrough in Tick-Borne Encephalitis Research
Tick-borne encephalitis (TBE) remains a growing public health challenge in Europe and Asia as tick and mosquito activity increases. In Sweden alone, health authorities reported 305 TBE cases up to August this year, signaling that 2024 may not reach the record highs of 2023 (595 cases) but is still higher than a decade ago. While vaccination is a proven tool for reducing disease risk, vaccination costs and personal choice mean that effective treatments for those who become infected are urgently needed. A new international study led by researchers at Karolinska Institutet may represent a crucial first step toward such therapy.
LRP8: The Receptor That May Open the Door to Treatment
The team identified a single host-cell protein, LRP8, as a key receptor used by the tick-borne encephalitis virus (TBEV) to invade human cells. LRP8 is a surface receptor expressed at high levels on neurons in the brain, the primary targets of TBEV. Using thousands of cultured cells with individual genes knocked out, researchers observed that cells lacking the LRP8 gene were notably resistant to infection. This pointed to LRP8 functioning as a critical doorway the virus uses to attach and enter the cell, an essential step in the disease process.
What the Findings Might Mean for Treatment
The identification of LRP8 as a necessary entry point for TBEV offers a promising direction for drug development. If scientists can design molecules that block the LRP8 receptor or disrupt the virus’s ability to bind to it, they may limit viral entry and reduce disease severity for those who become infected. While the work is early and largely preclinical, it establishes a concrete target for therapeutic strategies—not just for TBE, but potentially for related flaviviruses that exploit similar cellular doors.
Context in the Fight Against TBE
Flaviviruses, which include yellow fever, Japanese encephalitis, and dengue, share certain biological features. The discovery that a single host-cell protein such as LRP8 can act as a receptor for a flavivirus is noteworthy because it could guide the search for receptors and treatments across related diseases. The study’s senior author, Sara Gredmark Russ, a professor of infectious diseases at Karolinska Institutet, described the finding as the first time a solitary host-cell protein has been identified as a receptor essential for a flavivirus. This could accelerate both the development of targeted therapies and broader research into how these viruses interact with human cells.
Next Steps for Research and Public Health
Researchers emphasize that practical therapies will require extensive follow-up work, including validation in animal models and safety testing for any receptor-blocking approaches. If a therapeutic mechanism can be developed, it would supplement vaccination programs by offering a treatment option for people who contract TBE, potentially reducing the risk of severe neurological outcomes. In the meantime, vigilance against tick exposure, vaccination where available, and surveillance remain critical components of public health strategies against TBE.
About Tick-Borne Encephalitis
TBE is a viral infection transmitted primarily by ticks. It can cause mild flu-like symptoms and, in some cases, serious inflammation of the brain and spinal cord. Vaccines exist and are effective, but their uptake varies, and therapy to treat established infection has remained limited. Research such as this study at Karolinska Institutet signals a hopeful shift toward targeted, mechanism-based treatments that could mitigate the impact of TBE on patients and health systems.
