Detecting the replication of the hepatitis B virus using the ImmunoMax technique following treatment with interferon-alpha in children with chronic hepatitis.
BACKGROUND
Children with HBV in Poland are treated with preparations of interferon-alpha (IFN-alpha). The continuing lack of complete response to this type of anti-viral therapy remains to be explained. The application of cell biology techniques to identify the viral components in situ makes it possible to clarify the association between the distribution of the virus and morphological injury to the liver, the immune response of the host, and clinical symptoms in the natural course of infection. Our study was intended to evaluate HBV expression in liver biopsies taken an average of two years after completion of IFN-a therapy in 10 children with serological markers of persistent HBV infection.


METHODS
For the immunocytochemical detection of HBcAg and for the hybridocytochemical detection of HBV-DNA, the avidin-biotin-peroxidase (ABC) technique was employed, as well as classical in situ hybridization, both additionally amplified using the ImmunoMax technique. HBcAg and HBV-DNA levels were estimated using a semiquantitative technique.


RESULTS
Our study demonstrated persistent active replication of HBV in the liver in all examined children. A mixed pattern of HBcAg localization prevailed (noted in cell nuclei, cytoplasm and cell membranes) with a somewhat lower proportion of involved cells and a more evident membrane localization of HBcAg, as compared to results obtained before treatment. HBV-DNA was observed in the cytoplasm of a fraction of hepatocytes similar to that noted before therapy.


CONCLUSIONS
The ImmunoMax technique was found to be highly suitable for in situ monitoring of HBV replication after termination of IFN-a treatment. Children with focal distribution of HBcAg and HBV-DNA have the potential for earlier eradication of the virus from their livers.
Kasprzak
Aldona
A
Department of Histology and Embryology, Medical University of Poznan, Poland. akasprza@am.poznan.pl
Wysocki
Jacek
J
Zabel
Maciej
M
Surdyk-Zasada
Joanna
J
D000293:Adolescent; D001360:Avidin / Q000378:metabolism; D001710:Biotin / Q000378:metabolism; D002648:Child; D003584:Cytological Techniques; D005500:Follow-Up Studies; D006512:Hepatitis B Core Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000235:genetics*; D006521:Hepatitis, Chronic / Q000188:drug therapy* / Q000821:virology*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D016898:Interferon-alpha / Q000627:therapeutic use*; D008099:Liver / Q000821:virology; D009195:Peroxidase / Q000378:metabolism; D013997:Time Factors
D006512:Hepatitis B Core Antigens; D016898:Interferon-alpha; D001360:Avidin; D001710:Biotin; D009195:Peroxidase