Comparison of peptide enzyme-linked immunosorbent assay and radioimmunoprecipitation assay with in vitro-translated proteins for detection of serum antibodies to human papillomavirus type 16 E6 and E7 proteins.

Transcription of the human papillomavirus type 16 (HPV-16) genome is controlled by several promoters; the P97 promoter is considered to be the main one. An additional promoter has been identified within the E7 ORF as well as an antisense promoter just upstream of the L2 ORF. The significance of these promoters for early and late gene expression and their activity related to cell differentiation is not known in detail. Identification of two new, previously undescribed transcription start sites at nt 542 just upstream of the E7 ORF and at nt 611 within the E7 ORF is reported. The promoter responsible for the start site at nt 542 (P542) was active in SiHa, HeLa and C33A cells. Very low promoter activity was found upstream of the nt 611 start site. The E7 protein has previously been shown to be synthesized from a polycistronic mRNA encoding both the E6 and E7 proteins under the control of the P97 promoter. The data reported in the present paper suggest that promoter P542 may control synthesis of the E7 oncoprotein from a monocistronic mRNA.

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Mucosal but Not Parenteral Immunization with Purified Human Papillomavirus Type 16 Virus-Like Particles Induces Neutralizing Titers of Antibodies throughout the Estrous Cycle of Mice

Journal of Virology ◽

10.1128/jvi.73.11.9609-9613.1999 ◽

1999 ◽

Vol 73 (11) ◽

pp. 9609-9613 ◽

Cited By ~ 57

Author(s):

Denise Nardelli-Haefliger ◽

Richard Roden ◽

Carole Balmelli ◽

Alexandra Potts ◽

John Schiller ◽

...

Keyword(s):

Human Papillomavirus ◽

Estrous Cycle ◽

Neutralizing Antibodies ◽

Female Genital Tract ◽

Neutralization Assay ◽

Enzyme Linked Immunosorbent Assay ◽

Virus Like Particles ◽

Human Papillomavirus Type 16 ◽

Parenteral Immunization

ABSTRACT We have recently shown that nasal immunization of anesthetized mice with human papillomavirus type 16 (HPV16) virus-like particles (VLPs) is highly effective at inducing both neutralizing immunoglobulin A (IgA) and IgG in genital secretions, while parenteral immunization induced only neutralizing IgG. Our data also demonstrated that both isotypes are similarly neutralizing according to an in vitro pseudotyped neutralization assay. However, it is known that various amounts of IgA and IgG are produced in genital secretions along the estrous cycle. Therefore, we have investigated how this variation influences the amount of HPV16 neutralizing antibodies induced after immunization with VLPs. We have compared parenteral and nasal protocols of vaccination with daily samplings of genital secretions of mice. Enzyme-linked immunosorbent assay analysis showed that total IgA and IgG inversely varied along the estrous cycle, with the largest amounts of IgA in proestrus-estrus and the largest amount of IgG in diestrus. This resulted in HPV16 neutralizing titers of IgG only being achieved during diestrus upon parenteral immunization. In contrast, nasal vaccination induced neutralizing titers of IgA plus IgG throughout the estrous cycle, as confirmed by in vitro pseudotyped neutralization assays. Our data suggest that mucosal immunization might be more efficient than parenteral immunization at inducing continuous protection of the female genital tract.

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Human papillomavirus type 16 E6 and E7 oncoproteins interact with the nuclear p53-binding protein 1 in an in vitro reconstructed 3D epithelium: new insights for the virus-induced DNA damage response

Virology Journal ◽

10.1186/s12985-018-1086-4 ◽

2018 ◽

Vol 15 (1) ◽

Cited By ~ 4

Author(s):

Diletta Francesca Squarzanti ◽

Rita Sorrentino ◽

Manuela Miriam Landini ◽

Andrea Chiesa ◽

Sabrina Pinato ◽

...

Keyword(s):

Dna Damage ◽

Human Papillomavirus ◽

Dna Damage Response ◽

Binding Protein ◽

Human Papillomavirus Type 16 ◽

Damage Response ◽

E6 And E7 Oncoproteins ◽

E6 And E7

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Cooperative role of c-MYC and E6/E7 from two molecular variants of human papillomavirus type 16 upon proliferation and in vitro transformation of primary human keratinocytes

Revista de Medicina ◽

10.11606/issn.1679-9836.v98i1p53-59 ◽

2019 ◽

Vol 98 (1) ◽

pp. 52-58 ◽

Cited By ~ 1

Author(s):

Jimena Hochmann ◽

Silvaneide Ferreira ◽

João Sobrinho ◽

Laura Sichero

Keyword(s):

Human Papillomavirus ◽

Cellular Transformation ◽

Soft Agar ◽

Nuclear Antigen ◽

Hpv 16 ◽

Human Papillomavirus Type 16 ◽

In Vitro Transformation ◽

Molecular Variants ◽

E6 And E7

The roles of E6 and E7 oncoproteins of Human Papillomavirus type 16 (HPV-16) in the progression of immortalized epithelial cells to invasive tumors are not fully understood. Here, we establish a novel link between E6 and E7 of two molecular variants of HPV-16 (AA and E-350G), and c-MYC, regarding the cooperation in promoting malignant transformation of primary human foreskin keratinocytes (PHK). We aimed to study the synergistic effects of E6/E7 and c-MYC upon proliferation, and the in vitro transformation potential of PHK. We evaluated cellular proliferation through the expression of the Proliferating Cell Nuclear Antigen (PCNA) protein and colony formation abilities using soft agar and low attachment plates. We observed that E-350G-c-MYC PHKs exhibited discrete higher PCNA levels and formed significantly more colonies in both soft-agar and when growth in low-adhesion culture plates. Overall, we concluded that the E-350G variant co-transfected with c-MYC might promote malignant cellular transformation with a better efficiency than the AA-c-MYC counterpart. The enhanced oncogenic properties exhibited by the E-350G-c-MYC variant offer insights into mechanisms that may operate in human cervical neoplasia, given the higher frequency of its occurrence in the progression of high-grade precursor lesions to invasive carcinomas.

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