Detection of two forms of HBeAg (free-and IgG-bound HBeAg) in patients with HBe antigenemia using staphylococcus bearing protein A.
Protein A-bearing Staphylococcus aureus organisms (STA) were used to separate free HBeAg from IgG-bound HBeAg. Free HBeAg was detected in the supernate while IgG-bound HBeAg could be liberated from the pellets using MgCl2 or a glycine buffer. HBeAg was determined by radioimmunoassay and the results expressed as patient's cpm/normal control's cpm ratio (S/N ratio). This ratio was demonstrated to be proportionate to the antigen concentration and used as a titer of HBeAg. Sera of 40 HBsAg-negative healthy volunteers and 82 HBeAg-positive patients who were either asymptomatic HBsAg carriers or had various diseases including chronic persistent hepatitis (CPH), chronic active hepatitis (CAH), and renal disease undergoing hemodialysis, were tested for free HBeAg and IgG-bound HBeAg. Patients with CAH from two different countries were compared. Free HBeAg was detected in all patients but one, IgG-bound HBeAg was detected with similar prevalences (from 56% to 67%) in HBsAg asymptomatic carriers, hemodialysis patients, CPH and Italian CAH patients. In contrast, all CAH patients from New York, who had frequently been exposed to HBV infection, had detectable levels of IgG-bound HBeAg, with the highest S/N ratios observed in the study, and frequently showed an unfavorable outcome. In AVH due to HBV and delta agent co-infection, IgG-bound HBeAg was detected in two of four patients only in the initial stage of the disease. The data reported indicate that a separate determination of free- and IgG-bound HBeAg may have clinical value.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006509:Hepatitis B / Q000276:immunology*; D006511:Hepatitis B Antigens / Q000032:analysis*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D013205:Staphylococcal Protein A
D006511:Hepatitis B Antigens; D007074:Immunoglobulin G; D013205:Staphylococcal Protein A