Acute hepatitis B caused by a vaccine-escape HBV strain in vaccinated subject: Sequence analysis and therapeutic strategy

• Published in: Journal of clinical virology Vol. 62; pp. 89 - 91
• Main Authors: Luongo, Monica, Critelli, Rosina, Grottola, Antonella, Gitto, Stefano, Bernabucci, Veronica, Bevini, Mirco, Vecchi, Chiara, Montagnani, Giuliano, Villa, Erica
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2015
• Subjects: Acute hepatitis; Allergy and Immunology; Amino Acid Sequence; Escape mutant; Genotype; Hepatitis B - drug therapy; Hepatitis B - immunology; Hepatitis B - prevention & control; Hepatitis B - virology; Hepatitis B Surface Antigens - chemistry; Hepatitis B Surface Antigens - genetics; Hepatitis B Surface Antigens - immunology; Hepatitis B Vaccines - adverse effects; Hepatitis B Vaccines - genetics; Hepatitis B Vaccines - immunology; Hepatitis B virus; Hepatitis B virus - genetics; Hepatitis B virus - immunology; Humans; Infectious Disease; Male; Middle Aged; Molecular Sequence Data; Mutation; Sequence Alignment; Telbivudine; Vaccination - adverse effects; Vaccine; aa; anti-HBs; NAT; Escape mutant; Acute hepatitis; HBeAg; HBsAg; Vaccine; INR; ALTs; HBIG; Hepatitis B virus; HBV; Telbivudine; PCR; amino acid; hepatitis B surface antigen; hepatitis B virus; hepatitis B immune globulin; alanine aminotransferase; international normalized ratio; hepatitis B e antigen; nucleic acid amplification technology; anti-hepatitis B surface; polymerase chain reaction
• ISSN: 1386-6532; 1873-5967; 1873-5967
• DOI: 10.1016/j.jcv.2014.11.029

•HBsAg ‘a’ determinant mutants may cause failure of immunization.•The identified M125T, T127P and Q129H substitutions alter HBsAg secondary structure.•Impaired detection by neutralizing antibodies weakens protection against HBV.•Early antivirals may reduce disease course and favor immune function restoration. HBV vaccine contains the ‘a’ determinant region, the major immune-target of antibodies (anti-HBs). Failure of immunization may be caused by vaccine-induced or spontaneous ‘a’ determinant surface gene mutants. Here, we evaluate the possible lack of protection by HBV vaccine, describing the case of an acute hepatitis B diagnosed in a 55-year-old Caucasian male unpaid blood donor, vaccinated against HBV. Sequencing data for preS–S region revealed multiple point mutations. Of all the substitutions found, Q129H, located in the “a” determinant region of HBsAg, can alter antigenicity, leading to mutants. This mutant may cause vaccine failure especially when associated with high viremia of infecting source.