Full Length Research Paper

Production of recombinant proteins GST L1, E6 and E7 tag HPV 16 for antibody detection of Tunisian cervical cancer patients

Achour, M.¹*, Ben Younes, R.¹, Kochbati, L.², Kahla, S.¹, Zeghal, D.³, Maalej, M.², Zouari, F.³ and Oueslati, R.¹

¹Laboratory of Environmental Immuno-Microbiology and Cancerogenesis (IMEC Unit), Faculty of Sciences Bizerta 7021 Zarzouna, Tunisia.

²Service of Radiotherapy, Institute of Cancer Salah Azaeiz, Tunisia.

³Service of Gynecology- Obstetrics, Center of Maternity and Neonatalogy, Tunisia.

*Corresponding author. E-mail: mahaachour2000@yahoo.fr. Tel: 216 72 591 845 .Fax: 216 72 590 566.

Accepted 2 June, 2008

In the present work recombinant proteins were produced for used in LUMINEX in order to undergo serological study of Tunisian female population. HPV types 16 L1, E6 and E7 sequences fused to their 3’-end to a sequence encoding the terminal undecapeptide of the SV40 large T-antigen (tag) were isolated from plasmids and inserted into a pGEX vector for expression as GST fusion proteins in Escherichia coli. Coding sequences for L1tag, E6tag and E7tag of HPV 16 respectively were mobilized by digestion with enzymes and ligated into digested plasmids downstream of the GST domain. An expression plasmid for GST tag was constructed by inserting a fragment coding for the tag epitope. Data showed that the lysates were stable for detection and they were used in Luminex for detection of antibodies in female Tunisian female patients. This assay showed that the sero-positivity towards the different antigens depends upon the group studied and differences between cases and controls were significant (P <0.001). Elevated percentage of positivity was found for E7 (61%) versus 44 and only 21% for E6 and L1 antigens, respectively, and the intensity of the antibody response towards the late antigen L1 and the early antigens E6 and E7 were different.

Key words: T-antigen, LUMINEX, cervical cancer, HPV type 16, L1, E6 and E7.