TLR5 and hepatitis B virus infection: MPLA can act as an effective adjuvant in vaccines against malaria, HPV, and hepatitis B [185, 186]); TH1020 (inhibits TLR5 dimerization); and imiquimod (a synthetic imidazoquinoline) (TLR7 agonist and antagonist), and imidazoquinoline-based agents (TLR8 agonists and antagonists) are produced and some of them are approved by FDA for their use as vaccine adjuvants [8, 177, 179–181].