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Use of Interferon-γ Enzyme-linked Immunospot Assay to Characterize Novel T-cell Epitopes of Human Papillomavirus
Published on: March 8, 2012
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Replication interference between human papillomavirus types 16 and 18 mediated by heterologous E1 helicases
Seiichiro Mori1, Rika Kusumoto-Matsuo, Yoshiyuki Ishii
1Pathogen Genomics Center, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan. moris@nih.go.jp.
Virology Journal
|January 25, 2014
Summary
Human papillomavirus (HPV) co-infections cause replication interference between HPV16 and HPV18. Physical interaction between the E1 proteins of different HPV types mediates this interference, impacting viral replication.
Area of Science:
- Virology
- Molecular Biology
- Oncology
Background:
- Co-infection with multiple human papillomavirus (HPV) genotypes is common in women with abnormal cervical cytology.
- The molecular mechanisms of HPV inter-type replication interference remain largely unexplored.
Purpose of the Study:
- To investigate the molecular mechanisms of replication interference between HPV16 and HPV18 during co-infection.
- To determine the role of E1 and E2 proteins in HPV inter-type replication interference.
Main Methods:
- Co-transfection of HPV-negative C33A cells with HPV16 and HPV18 genomes and E1/E2 expression plasmids.
- Quantification of HPV genome replication using real-time PCR.
- Assessment of physical interaction between HPV16 and HPV18 E1 proteins using co-immunoprecipitation assays.
Main Results:
- Co-expression of heterologous E1/E2 proteins suppressed HPV16 and HPV18 genome replication.
- Replication interference was mediated by the E1 protein, specifically through its oligomerization domain.
- Physical interaction (co-precipitation) between HPV16 E1 and HPV18 E1 was observed, and impaired binding correlated with reduced inhibition.
Conclusions:
- Physical interaction between heterologous HPV E1 proteins is responsible for replication interference between HPV16 and HPV18.
- Formation of heterooligomers of HPV16/18 E1 proteins may impair their ability to support viral genome replication.
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