Introduction. Vaccine-induced protection by humoral immunity involves generating and maintaining immunoglobulin G-secreting cells (IgG-SCs) as a final goal for long-lasting protection. IgG-SCs arise from antigen-activated B cells within secondary lymphoid organs such as the spleen. This process is initiated by B cell receptor (BCR) binding to the antigen with potential additional co-stimulatory signaling by CD40, interleukin-4, and Toll-like receptors (TLRs)1,2,3,4,5,6. Reactive oxygen spe...