Cellular Immune Response to HBcAg in Mother-to-Infant Transmission of Hepatitis B Virus

✍ Scribed by Hong-Yuan Hsu; Mei-Hwei Chang; Kue-Hsiung Hsieh; Chin-Yun Lee; Ho-Hsiung Lin; Lih-Hwa Hwang; Pei-Jer Chen; Ding-Shinn Chen

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 800 KB
• Volume: 15
• Category: Article
• ISSN: 0270-9139
• DOI: 10.1002/hep.1840150505

✦ Synopsis

Cellular immunity to HBcAg was studied in hepatitis B virus carrier children and neonates born to hepatitis B virus carrier mothers. A significant proliferative response of peripheral blood mononuclear cells to HBcAg was found in 5 of 10 children with elevated ALT levels but in none of the nine HBeAgpositive children with normal ALT levels. HBeAg but not HBsAg was detected in cord blood of 9 of 10 neonates born to HBeAg-positive carrier mothers, suggesting exposure of these neonates to HBeAg in utero. However, cord mononuclear cells from neonates born to HBeAg positive carrier mothers did not show a significant change in the proportion of suppressor and helper T-cell subsets or proliferative response to HBcAg. Nor did they produce interleukin-2 receptor after being cocultured with HBcAg. The unresponsiveness of peripheral-blood mononuclear cells or cord mononuclear cells to HBcAg was not reversed by CD8+ cell depletion. Although cord blood mononuclear cells from neonates born to carrier mothers positive for antibody to HBeAg also did not respond to HBcAg, we encountered an infant, born to a carrier mother positive for antibody to HBeAg, who contracted acute hepatitis B at 2.5 mo of age. The baby's peripheral-blood mononuclear cells showed a significant proliferative response to HBcAg. These results support the view that transplacental maternal HBeAg probably induces a specific unresponsiveness of helper T cells to HBcAg and HBeAg in the neonates born to HBeAg-positive carrier mothers. This specific helper T cell tolerance could be maintained throughout the early replicative phase of carrier state but might break someday with the appearance of raised ALT level. (HEPATOLOGY 1992;15:

770-776.)

The outcome of HBV infection is determined by the interaction between host immune system and virus (1). Exposure to HBV in the perinatal period, as in neonates born to HBeAg-positive carrier mothers, frequently