“…have been detectable). Persistently infected HBV carriers without anti-HBc are very rare, but HBV-naïve patients may become persistently infected and may not develop anti-HBc antibodies, if they are infected with HBV while on chemotherapy (Repp et al, 1993) or occasionally after perinatal infection (Chan et al, 1994;Kagimoto et al, 1991;Laperche et al, 2001;Lee et al, 1989;Ni et al, 1993). In fact, the reconstitution of the immune system after stem cell transplantation as shown here partially resembles the B cell ontogeny (Storek et al, 1993(Storek et al, , 1995 and thus may resemble to perinatal infection.…”