Hepatitis D and B virus genotypes in chronically infected patients from the Eastern Amazon Basin

Gomes‐Gouvêa, Michele Soares; Soares, Manoel do Carmo Pereira; Carvalho-Mello, Isabel Maria Vicente Guedes de; Brito, E. M. F.; Moia, Lizomar de Jesus Maués Pereira; Bensabath, Gilberta; Nunes, Heloisa Marceliano; Carrilho, Flair José; Pinho, João Renato Rebello

doi:10.1016/j.actatropica.2008.02.009

Cited by 37 publications

(41 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The packaging signal is very genotype specific in HDV (74% divergence between genotypes 1 and 2) and plays an important role in the envelopment. Although an association between HDV-1/HBV-A and -D and HDV-3/HBV-F and -A has been observed, independent investigations suggest that the co-infections are mainly representative of common genotypes of each of the viruses in certain geographical areas and not specific for distinct HBV or HDV genotypes [13][14][15] . Studies indicate that HDV genotype 2 is associated with a less aggressive disease compared to genotype 1 which has been attributed to the higher packaging efficiency of genotype 1 than that of genotype 2 [16,17] .…”

Section: Hbsag-hdag Interactionsmentioning

confidence: 99%

Molecular interactions between hepatitis B virus and delta virus

Shirvani-Dastgerdi¹

2015

WJV

View full text Add to dashboard Cite

HBV HBsAgs. While HBsAg is the only protein required by HDV, the exact interaction sites between the S protein and pre-mature HDV are not well defined yet. In fact, these sites are distributed along the S protein with some hot spots for the envelopment process. Moreover, in most clinically studied samples, HDV infection is associated with a dramatically reduced HBV viral load, temporarily or permanently, while HBsAg resources are available for HDV packaging. Thus, beyond interacting with HBV envelope proteins, controlling mechanisms exist by which HDV inhibits HBV-DNA replication while allowing a selective transcription of HBV proteins. Here we discuss the molecular interaction sites between HBsAg and the HDV-RNP complex and address the proposed indirect mechanisms, which are employed by HBV and HDV to facilitate or inhibit each other's viral replication. Understanding molecular interactions between HBV and HDV may help to design novel therapeutic strategies for delta hepatitis. Core tip: Hepatitis D virus (HDV) causes accelerated liver disease in form of fulminant or chronic hepatitis in patients with hepatitis B virus (HBV) infection. HBV supports HDV replication by sharing its surface proteins. Even without overt HBV-DNA replication, transcription of HBV surface proteins (HBsAgs) remains stable in HDV infected cells, which is essential for assembly of HDV virions containing HBsAg proteins. HDV replication is oftentimes associated with a suppression of HBV-DNA levels, and several mechanisms have been suggested how HBV or HDV may influence each other's replication. Understanding molecular interactions between HBV and HDV may help to design novel therapeutic strategies. Molecular interactions between hepatitis B virus and delta virus AbstractAs a deficient virus due to the lack of envelope proteins, hepatitis D virus (HDV) causes chronic or fulminant "delta hepatitis" only in people with simultaneous hepatitis B virus (HBV) infection. HBV encodes three types of surface proteins known as small (S), medium (M) and large (L) envelope proteins. All three types of HBV surface antigens (HBsAgs) are present on HDV virions. The envelopment process of HDV occurs through interactions between the HDV ribonucleoprotein (RNP) complex and 36 EDITORIALSubmit a

show abstract

Section: Hbsag-hdag Interactionsmentioning

confidence: 99%

Molecular interactions between hepatitis B virus and delta virus

Shirvani-Dastgerdi¹

2015

WJV

View full text Add to dashboard Cite

show abstract

“…HDV-2, formerly referred to as genotype-IIa, is found in Japan, Taiwan and Russia [11,13,25]. HDV-3 has been isolated in the Amazon region of Peru, Colombia, Ecuador, Venezuela, and Brazil [12,23,26,27]. HDV-4, formerly referred to as genotype-IIb, is found in Taiwan and Japan [13,25,28].…”

Section: Introductionmentioning

confidence: 99%

“…HDV-3 is responsible for epidemics of severe and fulminant hepatitis, which are common in northeastern South America [12]. HDV-3 is prevalent in the Brazilian Amazon and is associated with an increased aggressiveness of HDV infection [12,23,24,26,27]. …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of the Genotypic Profile of Hepatitis Delta Virus: Isolation of HDV Genotype-1 in the Western Amazon Region of Brazil

Botelho-Souza¹,

Vieira²,

Santos³

et al. 2015

Intervirology

View full text Add to dashboard Cite

The hepatitis delta virus (HDV) is a hepatotropic subvirus that is dependent on the hepatitis B virus (HBV) and supplies the viral envelope containing the surface antigen of hepatitis B. Viral genetic diversity is related to the geographical origin of the isolates, and there are at least eight genotypes that are referred to as HDV-1 through HDV-8. HDV-3 is responsible for epidemics of severe and fulminant hepatitis, which are common in northeastern South America. HDV-3 is prevalent in the Brazilian Amazon and is associated with the increased aggressiveness of HDV infections. Although isolated, the characteristics of the clinical presentation of HDV-1 in the Amazon region have not yet been clearly reported. Objective: This study aims to assess the genotypic and clinical characteristics of individuals with the HDV-1 genotype in the western Amazon region. Methods: The HDV was genotyped by nested PCR-RFLP and sequencing from serum samples of 56 patients with HBV/HDV infection. The genotypes were correlated with the clinical characteristics presented by patients with HBV/HDV infection. Results: A prevalence of 92.3% for the HDV-3 genotype (n = 48) and 7.6% (n = 4) for the HDV-1 genotype was observed. Conclusion: To date, this is the most extensive clinical study of HDV-1 genotype infections in the nonindigenous population of Western Amazonia.

show abstract

“…HDV utilizes the envelope proteins of HBV to assemble virus particles for new rounds of infection (193). Studies have shown that HDV infection often occurs as a superinfection in HBV patients and increases the risk of hepatitis and liver damage (194,195). It still is unclear whether super-or co-infection of HDV in HBV-positive individuals increases the relative risk for HCC.…”

Section: Hbv and Hdvmentioning

confidence: 99%

Multiple Infections and Cancer: Implications in Epidemiology

Vedham

Divi

Starks

et al. 2014

Technol Cancer Res Treat

View full text Add to dashboard Cite

Approximately 18% of the global cancer burden has been attributed to infectious agents, with estimates ranging from 7% in developed countries to about 22% in developing countries.Chronic infections caused by the hepatitis B and C viruses, human papilloma viruses (HPV), and Helicobacter pylori (H. pylori) are reported to be responsible for approximately 15% of all human cancers. Interestingly, although many of the infectious agents that have been associated with cancer-such as HPV, Epstein-Barr virus (EBV), and H. pylori-are highly prevalent in the world, most infected individuals do not develop cancer but remain lifelong carriers. Malignancies associated with infectious agents may result from prolonged latency as a result of chronic infections. Pathogenic infections are necessary but are not sufficient for cancer initiation or progression. Cancer initiation may require additional cofactors, including secondary infections. Therefore, in patients with chronic infection with one agent, secondary co-infection with another agent may serve as an important co-factor that may cause cancer initiation and progression. Additionally, opportunistic co-infections could significantly inhibit response to cancer treatment and increase cancer mortality. Co-infections are relatively common in areas with a high prevalence of infectious agents, especially in developing countries. These co-infections can cause an imbalance in the host immune system by affecting persistence of and susceptibility to malignant infections. Several articles have been published that focus on infectious agents and cancer. In this article, we discuss the role of infectious agents in malignancies, highlight the role of multiple/co-infections in cancer etiology, and review implications for cancer epidemiology.

show abstract

Hepatitis D and B virus genotypes in chronically infected patients from the Eastern Amazon Basin

Cited by 37 publications

References 37 publications

Molecular interactions between hepatitis B virus and delta virus

Molecular interactions between hepatitis B virus and delta virus

Characterization of the Genotypic Profile of Hepatitis Delta Virus: Isolation of HDV Genotype-1 in the Western Amazon Region of Brazil

Multiple Infections and Cancer: Implications in Epidemiology

Contact Info

Product

Resources

About