Hepatitis B virus surface protein mutations clustered mainly in CTL immune epitopes in chronic carriers: results of an Iranian nationwide study

@article{Khedive2013HepatitisBV,
  title={Hepatitis B virus surface protein mutations clustered mainly in CTL immune epitopes in chronic carriers: results of an Iranian nationwide study},
  author={Abolfazl Khedive and Mehdi Norouzi and Fatemeh Ramezani and Hadi Karimzadeh and Sm Alavian and Reza Malekzadeh and Ghodratollah Montazeri and Azim Nejatizadeh and Masoud Ziaee and Farshid Abedi and Behrooz Ataei and Majid Yaran and Babak Sayad and Mohamad hosein Somi and Gholamreza Sarizadeh and Ismail Sanei-Moghaddam and Fariborz Mansour-Ghanaei and Houshang Rafatpanah and Mohammad Amin Pourhosseingholi and Hossein Keyvani and Ebrahim Kalantari and Mehdi Saberifiroozi and M A Judaki and Shiva Ghamari and Maryam Daram and M Khaksari Mahabadi and Zeinab Fazeli and Zahra S Goodarzi and Vahdat Poortahmasebi and Seyed Mohammad Jazayeri},
  journal={Journal of Viral Hepatitis},
  year={2013},
  volume={20}
}
Mutations within the coding region of hepatitis B surface antigen (HBsAg) have been found naturally in chronic carriers. To characterize the mutations of HBsAg from Iranian chronic carriers who were vaccine and/or medication naive. The surface genes from 360 patients were amplified and directly sequenced. The distribution of amino acid substitutions was classified according to different immune epitopes of the surface protein. All isolates belonged to genotype D. 222 (61.6%) of 360 patients… 
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23 Citations
Background Citations
5
Methods Citations
4
Results Citations
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23 Citations

Citation Type

Citation Type

Incidence of Hepatitis B virus Surface Antigen (HBsAg) Mutations in Naïve Treated of Chronic Carriers from Tehran Metropolis, Iran
TLDR
HBV mutants within the immune epitopes of surface Ag seem to be extremely common among chronic carriers from Tehran, especially those who are anti-HBe positive, indicating that after HBeAg seroconversion, due to the selection pressure of Ag e antibody, the occurrence of mutation is an inevitable effect of the evolutionary process.
Analysis of Antigenic and Conformational Changes in Hepatitis B Surface Antigen (HBsAg) Identified in Iranian Patients with Chronic Hepatitis B
TLDR
The current analyses revealed that the studied mutations induced a local change in the ‘a’ determinant conformation, which could be useful for the design ofHBsAg detection assays, which may significantly improve the ability to detect particular HBsAg mutants.
Clinical features and viral quasispecies characteristics associated with infection by the hepatitis B virus G145R immune escape mutant
TLDR
The dynamic changes in the serological and virological markers in a case of hepatitis B with coexisting HBsAg and anti-HBs, caused by a G145R immune escape mutant (genotype C), are described to extend understanding of the evolution of HBV under host immune pressure and of the clinical outcomes of affected patients.
Hepatitis B Virus Genotype D is the Only Genotype Circulating in Iranian Chronic Carriers, the Unique Pattern of Genotypic Homogeneity
TLDR
The uniqueness pattern of HBV genetics hemogeniety together with the low mutational frequency indicated that HBV has introduced to Iran recently and isolation of people in the absence of intermixing with other genotypes led to a homologous pattern.
Nucleotide Substitutions in Hepatitis B Viruses Derived from Chronic HBV Patients
TLDR
Common mutations within HBsAg, occurring in immune epitopes, a high rate of G1896A mutations in the PC region, and a negative correlation between the emergence of A1762T/G1764A mutation and the G1764T/C1766G mutant in the BCP region were shown.
Naturally Occurring Surface Antigen Variants of Hepatitis B Virus in Tunisian Patients
TLDR
A high prevalence of naturally occurring HBsAg variants was observed among Tunisian HBV carriers, and tended to be higher in liver cirrhosis than in chronic infection.
Evolution of hepatitis B virus surface gene and protein among Iranian chronic carriers from different provinces
TLDR
Further to low selection pressure found in Iranian population, the variations between different regions designate random genetic drift within the surface proteins.
A new vaccine escape mutant of hepatitis B virus causes occult infection
TLDR
Three new mutations (S171F, S174N and Q181R) at the antigenic epitopes of HBV presented by HLA class I molecules are found, causing vaccine escape and occult infection.
Hepatitis B virus surface gene mutants in immunoprophylaxis‐failed infants from Southern China
TLDR
Investigation of HBV surface antigen (HBsAg) variations in immunoprophylaxis‐failed infants, vaccine free infant patients and adult chronic hepatitis B (CHB) patients found substitutions in “a” determinant, especially the G145 substitution was still the most stable and remarkable site of vaccine escape.
The Impact of HBV Quasispecies Features on Immune Status in HBsAg+/HBsAb+ Patients With HBV Genotype C Using Next-Generation Sequencing
TLDR
It is indicated for the first time that point mutations and quasispecies diversities of HBV s gene could alter the MHR antigenicity and CTL Se immunogenicity and could contribute to the concurrent HBsAg+/HBsAb+ with different features in HCC and CHB.
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