TLR9 and viral infectious disease: Since type I IFN signaling is critical for protection against several viral infections, rASP-1 stands to be a new addition to other known type I IFN stimulating adjuvants such as Poly I:C (TLR3 agonist), R848 (TLR7/8 agonist), CpG (TLR9 agonist) and STING agonists.