Figure 1.

Summary of adaptive antiviral immune responses, (A) Number of potential vaccines entered into clinical trials, (B) When the vaccine is administered, it can be detected by internal sensors within cells, triggering the activation of the innate immune system, which leads to the creation of cytokines and IFNs, (C) adaptive immunity system: Dendritic cells mature in response to the interferons (IFNs) and cytokines produced, and then travel to peripheral lymphoid organs. In these organs, mature dendritic cells present antigens to T cells using either major histocompatibility complex (MHC) class I or MHC class II complexes, which bind to CD8+ or CD4+ T cells respectively. Through MHC‐II, dendritic cells activate CD4+ T cells or helper T cells and regulate the immune response by secreting cytokines. They also activate B cells, initiating antibody class switching via CD40/CD40L signaling. Activated B cells transform into plasma cells that produce various types of antibodies, crucial for the adaptive immune response. Additionally, dendritic cells promote the expansion and differentiation of CD8+ T cells by producing interleukin‐2 (IL‐2) and expressing interferon‐gamma (IFN‐γ), tumor necrosis factor‐alpha (TNF‐α), and IL‐2. These CD8+ T cells can mature into cytotoxic T lymphocytes (CTLs) upon activation, generating perforin and other cytokines that can enhance vaccine effectiveness. Circulating T follicular helper (cTfh) cells aid in B‐cell maturation and the production of high‐affinity antibodies. Image created by PM using BioRender (https://biorender.com/).