Anti-preS responses influence the anti-HBs response in newborns after vaccination with the third generation Sci-B-Vac™ vaccine

We analysed the specificity and significance of the antibody response towards the linear preS1 sequence that has been shown to represent the “hepatocyte binding site” comprising amino acids preS1 (21–47) or the specific preS2 (131–140) antibody response to the “polymerised albumin receptor” in relation to the antibody response to hepatitis B surface antigen during immunisation of healthy children with the preS-containing Sci-B-Vac™ vaccine. Twenty-eight healthy newborns received three doses of the Sci-B-Vac™ vaccine according to a 0-, 1-, and 6-month scheme. Seventeen (61%) of the 28 newborns had detectable levels of anti-preS1 (21–47) antibodies and 14 (50%) were anti-preS2 (131–140) reactive at 6 and/or 9 months after initiation of the vaccination. The mean levels of anti-HBs were significantly higher in the anti-preS2 (131–140) non-reactive (24 580 ± 7815 IU/l, mean + SEM) compared with the reactive sera (7287 ± 2317 IU/l, p < 0.025). The highest anti-HBs levels were found in newborns who exhibited reactivity towards the aa 21–47 of the preS1 but lacked anti-preS2 (131–140) reactivity.