CpG DNA overcomes hyporesponsiveness to hepatitis B vaccine in orangutans

Oligonucleotides containing immunostimulatory CpG motifs (CpG ODN) have bee n shown to be potent Th1-type adjuvants far augmenting antigen-specific res ponses in mice against hepatitis B surface antigen (HBsAg), The hepatitis B virus (HBV) infects only humans and great apes and appears to exist among wad chimpanzees and orangutans, An outbreak of HBV among orangutans being r ehabilitated for re-introduction to the jungle caused the death of several animals. A prophylactic vaccination program revealed that orangutans are qu ite hypo-responsive to a current commercial vaccine compared to results obt ained previously in humans and chimpanzees. Addition of CpG ODN to hepatiti s B vaccine greatly increased the seroconversion rate and the titers of ant ibody against HBsAg (anti-HBs). This is the first: demonstration of CpG DNA in a great ape and the results have important implications for the vaccina tion of humans against HBV and other diseases. (C) 2000 Elsevier Science Lt d. All rights reserved.