Putta MR, Bhagat L, Wang D, Zhu FG, Kandimalla ER, Agrawal S. Immune-Stimulatory Dinucleotide at the 5'-End of Oligodeoxynucleotides Is Critical for TLR9-Mediated Immune Responses. ACS Med Chem Lett. 2013 Feb 14; 4(2):302-5.