[Hepatitis B immunoglobulins blocking hepatitis B virus infection of trophoblast cell culture in vitro].
OBJECTIVE
To determine the role of hepatitis B Immunoglobulins (HBIG) in blocking hepatitis B virus (HBV) infection of trophoblast cell culture in vitro.


METHODS
Trophoblast cells were placed in the six-well cluster dishes and incubated with 10% fetal calf serum/Dubecco's modified Eagle's Medium (10% FCS DMEM) at 37 degrees C with 5% CO2 in air. At 24 h after plating cells were subjected to experiment. Group A: cells were cultured with 0.5 ml HBV positive serum plus 3 ml 2% FCS DMEM; Group B: cells were cultured with 3 ml 2% FCS DMEM plus 0.5 ml HBV positive serum pretreated with 80 U HBIG for 30 min at 37 degrees C; Group C: cells were cultured with 3 ml 2% FCS DMEM plus 0.5 ml HBV positive serum pretreated with 40 U HBIG for 30 min at 37 degrees C; Group D: cells were cultured with 3 ml 2% FCS DMEM plus 40 U HBIG for 30 min before 0.5 ml HBV positive serum was added; Group E: cells were cultured with 40 U HBIG plus 3 ml 2% FCS DMEM; Group F: cells were cultured with HBV negative serum plus 3 ml 2% FCS DMEM. Twenty-four hours later the inoculums were removed, and the cells were extensively washed with 0.01 mol/L phosphate-buffered saline (PBS). After PBS washing, 4 ml 2% FCS DMEM was added to each well and the medium was collected every 12 hours. Enzyme-Linked Immunosorbent Assay (ELISA) method was used to detect HBsAg in culture medium (absorption value, A). HBV DNA in cell culture medium was detected by polymerase chain reaction (PCR).


RESULTS
Before PBS washing, the A value of groups A, B, C, D, E, F were 2.697, 0.040, 0.102, 0.198, 0.036, 0.040 respectively. The cell culture medium in groups of A, B, C, and D were HBV DNA positive, groups of E, F were HBV DNA negative. From 12 hours to 84 hours, the average A value of groups A, B, C, D, E and F was 1.55 +/- 0.27, 0.032 +/- 0.016, 0.100 +/- 0.087, 0.052 +/- 0.044, 0.034 +/- 0.020, 0.034 +/- 0.022 respectively. The A value of groups A was significantly higher than those of other groups (P < 0.01). Cell culture medium at 84 hours of group A was HBV DNA positive and those of group B, C, D, E, F were HBV DNA negative.


CONCLUSIONS
HBIG could effectively block HBV infection of trophoblast cell culture in vitro.
Wang
An-hui
AH
Department of Epidemiology, Fourth Military Medical University, Xi'an 710032, China.
Men
Ke
K
Yan
Yong-ping
YP
Xu
De-zhong
DZ
Lu
Juan
J
Wang
Xue-ping
XP
Zhang
Jing-xia
JX
D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000737:chemistry; D004279:DNA, Viral / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics / Q000276:immunology; D006801:Humans; D007136:Immunoglobulins / Q000008:administration & dosage / Q000494:pharmacology*; D011247:Pregnancy; D014327:Trophoblasts / Q000166:cytology / Q000187:drug effects* / Q000276:immunology
D017077:Culture Media, Conditioned; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D007136:Immunoglobulins; C045213:hepatitis B hyperimmune globulin