Long-term immune reactivity to pre-S(2)-antigen after acute hepatitis B infection.

We investigated sera from 39 patients, taken 1-8 years after recovery from acute hepatitis B for anti-pre-S(2) by Western blotting and for anti-HBs by radioimmunoassay. Anti-pre-S(2) antibodies were found in 27 out of 39 sera (69%) with the highest frequency in sera with anti-HBs greater than 100 IU/I (92%). However, sometimes sera with low anti-HBs titres showed a strong response in Western blotting. Acute hepatitis sera were also investigated from a limited number of patients (n = 14). Anti-pre-S(2) antibodies were found during antigenaemia (four out of six patients) and within 3 months after the maximum of alanine amino transferase (ALAT) (seven out of ten patients). Anti-pre-S(2) is an early antibody. It remains in the circulation for many years similar to but independent of anti-HBs.