RIG-I ligands and methods for producing them

An oligonucleotide comprising a sense strand and an antisense strand, wherein the oligonucleotide comprises

• a sense strand comprising nucleotide sequence 5′ GACGCUGACCCUGAAmGUUCAUCUU 3′ (SEQ ID NO:32);
• and
• an antisense strand comprising nucleotide sequence 3′ CUGmCGACUGGGACUUCAAGUAGAA 5′ (SEQ ID NO:33);
• wherein the nucleotide indexed m is 2′-O-methylated.