Activation and Immunomodulatory Roles of TLR7 and TLR8 in Enhancing Vaccine Efficacy and Immune Responses
A Systematic Review
DOI:
https://doi.org/10.58445/rars.1322Keywords:
TLR7, TLR8, VaccineAbstract
Toll-like receptors (TLRs) 7 and 8 recognize single-stranded RNA (ssRNA) from viruses, initiating immune responses. This systematic review evaluates their roles in enhancing immune responses, vaccine efficacy, autoimmune diseases, and cancer immunotherapy. A comprehensive search identified studies from the past ten years. This paper will focus on TLR7 and TLR8 activation mechanisms, their effects on immune cell functions, and their therapeutic potential across various medical applications. TLR7 activation enhances interferon-alpha production, B-cell activation, and antibody responses, which are essential for antiviral defense and vaccine efficacy. TLR8 activation induces pro-inflammatory cytokines and enhances CD8+ T-cell responses, aiding vaccine efficacy and offering therapeutic potential for HIV-1 latency reversal and chronic hepatitis B. In cancer immunotherapy, TLR7/8 agonists remodel tumor and host responses, reduce tumor mass, and enhance T-cell activity. Despite promising results, limitations include study heterogeneity, reliance on animal models, and the need for standardized methodologies. Future research should focus on translating preclinical findings into clinical applications, balancing immune activation with the risk of autoimmunity, and exploring synergistic combinations with other immunotherapies. TLR7 and TLR8 are promising targets for enhancing immune responses and developing therapies for infectious diseases, autoimmune disorders, and cancer.
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