title: The novel use of a routine quantitative system to analyze the activity, content and affinity of an antibody to hepatitis B core antigen.
abstract: BACKGROUND
  Currently, quantitative measurement of serum markers of HBV infection has been widely used, but commonly used analysis for specific antibodies only involves the measurement of the total antibody activity, and the binding affinity or protein content is rarely analyzed.
  
  
  OBJECTIVE
  To investigate the detailed features of an antibody to hepatitis B core antigen (anti-HBc) during different periods of hepatitis B virus (HBV) infection with a new method of analysis.
  
  
  METHODS
  Serum samples were collected from patients that were positive for the anti-HBc antibody. On the basis of the other serological markers in the samples, all patients were divided into a hepatitis B surface antigen (HBsAg)-positive group and an antibody to hepatitis B surface antigen (anti-HBs)-positive group. All samples were diluted 2-, 20- and 200-fold. Anti-HBc quantification was measured with a chemiluminescent microparticle immunoassay; total anti-HBc activity, protein content and affinity were calculated according to a measured value of each dilution. Serum HBV DNA load and alanine aminotransferase (ALT) levels were also measured.
  
  
  RESULTS
  The total anti-HBc activity in the HBsAg-positive group was statistically higher than that in the anti-HBs-positive group (p<0.05). The anti-HBc protein content during active HBV infection was statistically higher than during the convalescence stage (p<0.05), while anti-HBc affinity during HBV infection was lower than during recovery. There were correlations among total activity, affinity, protein content of anti-HBc, and ALT, HBV-DNA (p<0.05).
  
  
  CONCLUSIONS
  It is potentially possible to predict the status of HBV infection by measuring total activity, protein content and affinity of anti-HBc.
authors: Department of Clinical Immunology, Dalian Medical University, Dalian 116044, China.
authors: Yanan
authors: Y
authors: Han
authors: Bo
authors: B
authors: Wang
authors: Hui
authors: H
authors: Liu
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D000915:Antibody Affinity; D004279:DNA, Viral / Q000097:blood; D005260:Female; D006509:Hepatitis B / Q000276:immunology*; D006510:Hepatitis B Antibodies / Q000097:blood* / Q000737:chemistry / Q000276:immunology*; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D044967:Serum / Q000276:immunology; D019562:Viral Load
chemical_list: D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D000410:Alanine Transaminase