Free Immunoglobulin Light Chains in Patients with Tick-borne Encephalitis: Before and After Treatment

Leila Abadi^*
*Correspondence: Leila Abadi, Department of Immunology, University of Toronto, 27 King’s College Cir, Toronto, ON M5S 1A1, Canada, Email:

Keywords

Free immunoglobulin light chains • Tick-borne encephalitis • Biomarkers • Disease progression

Introduction

Tick-Borne Encephalitis (TBE) is a viral infection transmitted by ticks, primarily in Europe and Asia, with increasing prevalence and clinical significance. It belongs to the Flavivirus genus and can cause severe neurological complications, ranging from meningitis to encephalitis. Despite advances in diagnosis and treatment, TBE remains a significant public health concern due to its potential for long-term neurological sequelae. The immune response to TBE virus infection involves various components, including immunoglobulins produced by B lymphocytes. Immunoglobulin light chains, specifically free immunoglobulin light chains have garnered attention as potential biomarkers in various infectious and autoimmune diseases. FLCs are small polypeptide chains produced during the synthesis of immunoglobulins and can be detected in serum and cerebrospinal fluid their levels and ratios have been linked to disease activity, progression, and treatment response in several conditions. This article aims to review the current understanding of FLCs in patients with TBE, focusing on their role as biomarkers before and after treatment. By summarizing existing literature and discussing potential implications, we seek to highlight the relevance of FLC assessment in TBE management and identify areas for future research [1].

The pathophysiology of TBE involves the entry of TBEV into the bloodstream following a tick bite. The virus then crosses the blood-brain barrier, leading to neuroinvasion and subsequent neurological symptoms. The host immune response, including both innate and adaptive components, plays a crucial role in controlling viral replication and limiting tissue damage. Immunoglobulins, including IgG and IgM, are produced in response to TBEV infection. These antibodies target viral antigens and facilitate virus neutralization and clearance. The levels of specific antibodies are often measured to diagnose TBE and monitor immune response dynamics during infection and recovery. FLCs are generated during the synthesis of immunoglobulins and are released into circulation. They consist of kappa and lambda chains and can be detected in serum and CSF. In various disease states, including infections and autoimmune disorders, FLC levels may be dysregulated, reflecting immune system activation and tissue damage.

Literature Review

Studies have investigated the utility of FLCs as biomarkers in infectious diseases, such as HIV, tuberculosis, and viral hepatitis. Elevated FLC levels have been associated with disease severity, progression, and treatment response. In autoimmune conditions like multiple sclerosis and rheumatoid arthritis, FLCs have also shown promise as markers of disease activity and therapeutic efficacy. Limited research has explored FLCs in TBE patients specifically. However, preliminary studies suggest that FLC levels may be altered during acute infection and correlate with neurological manifestations. Monitoring FLC dynamics before and after treatment could provide insights into disease progression and recovery trajectories. Evaluating FLC changes following TBE treatment, such as antiviral therapy and supportive care, may help assess treatment efficacy and predict clinical outcomes. FLC ratios, including kappa-to-lambda ratios, could serve as additional indicators of immune system modulation and neuroinflammatory processes [2].

Discussion

The literature reviewed highlights the potential significance of FLCs in patients with tick-borne encephalitis both as diagnostic biomarkers and indicators of disease progression and treatment response. While current research on FLCs in TBE is limited, existing evidence from other infectious and autoimmune conditions suggests several avenues for future investigation and clinical application. Assessing FLC levels in TBE patients, particularly in the acute phase, may aid in early diagnosis and risk stratification. Elevated FLCs could indicate heightened immune activation and neuroinflammation, prompting closer monitoring and timely intervention [3].

Longitudinal FLC measurements before and after treatment could provide insights into disease course and prognosis. Persistent elevation or fluctuation of FLCs post-treatment may signify ongoing immune dysregulation or incomplete viral clearance, warranting further evaluation and management adjustments. Monitoring FLC changes alongside conventional markers, such as antibody titers and cytokine profiles, may enhance the assessment of treatment response. A decrease in FLC levels or normalization of FLC ratios following therapy could correlate with clinical improvement and recovery [4]. FLCs, particularly in the cerebrospinal fluid may serve as markers of neuroinflammation and blood-brain barrier integrity. Their association with intrathecal immunoglobulin synthesis and neurologic symptoms merits exploration in TBE patients with neurological complications. FLCs in Vaccine Development: Understanding FLC dynamics in vaccinated individuals and their correlation with protective immunity could inform TBE vaccine development and efficacy monitoring. FLCs may complement traditional serological assays in assessing vaccine-induced immune responses [5,6].

Conclusion

Challenges and Future Directions: Standardization of FLC measurement methods, establishment of reference ranges in TBE populations, and largescale prospective studies are needed to validate the clinical utility of FLCs in TBE. Addressing these challenges will facilitate the integration of FLC assessment into routine diagnostic and therapeutic algorithms for TBE management. In conclusion, Free Immunoglobulin Light Chains (FLCs) represent a promising area of research in Tick-Borne Encephalitis (TBE), offering insights into disease pathophysiology, prognosis, and treatment response. Further investigation and validation of FLCs as biomarkers in TBE are warranted to enhance clinical decision-making and improve patient outcomes. Integrating FLC assessment into comprehensive TBE management protocols may contribute to more personalized and effective care strategies.

Acknowledgement

None.

Conflict of Interest

None.

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