From the Guidelines
Epstein-Barr virus (EBV) can upregulate Th2 immune responses for an indefinite period, potentially lasting years or even a lifetime, following initial infection. After primary infection, EBV establishes lifelong latency in B cells and can periodically reactivate, potentially maintaining Th2 dominance indefinitely in susceptible individuals 1. This Th2 skewing occurs as EBV produces proteins like EBNA1 and LMP1 that promote interleukin-10 production and inhibit Th1 responses. The virus also interferes with interferon signaling pathways, further enhancing Th2 predominance.
Some key points to consider:
- The duration and intensity of Th2 dominance varies significantly between individuals based on genetic factors, overall immune status, viral load, and concurrent infections or inflammatory conditions.
- EBV serologic tests generally reveal high IgG antibody titers against EBV VCA and EA in patients with chronic active EBV infection, although an increase of only circulating EBV DNA was shown in some patients 1.
- Addressing EBV-induced Th2 dominance often requires a multifaceted approach focusing on immune modulation rather than direct antiviral therapy, as no specific treatment exists to completely eliminate latent EBV.
- The prolonged Th2 upregulation may contribute to various immune-mediated conditions including allergic disorders, certain autoimmune diseases, and chronic fatigue syndrome.
Given the complexity of EBV infection and its impact on the immune system, a comprehensive treatment plan should prioritize immune modulation and management of related immune-mediated conditions. This approach may involve monitoring viral load, managing symptoms, and addressing underlying immune dysregulation to mitigate the effects of prolonged Th2 upregulation 1.
From the Research
EBV Infection and Immune Response
- EBV infection can result in long-term immune damage and decreases the productivity of many college students 2
- The virus establishes a latent infection in B cells in the blood, and the latent EBV load in healthy individuals is generally stable over time, maintaining a "set point" 3
Effect of Antiviral Therapy on EBV
- Valacyclovir therapy caused a reduction of EBV excretion and possibly produced a clinical benefit in infectious mononucleosis 2
- Long-term administration of valacyclovir reduces the number of EBV-infected B cells but not the number of EBV DNA copies per B cell in healthy volunteers 3
- Valganciclovir reduced the proportion of days with EBV detected and the quantity of virus detected in a randomized, double-blind, placebo-controlled study 4
EBV and TH2 Response
- There is no direct evidence in the provided studies on how long EBV upregulates TH2 response long term
- However, it is known that EBV infection can lead to changes in the immune response, including the activation of different types of immune cells 2, 3