SCREENING OF NOVEL NANO BODIES AGAINST HPV16E6
The persistent infection of high-risk human papillomavirus (HPV) is one of the most common causes of cervical cancer. It is well documented that expression of two oncogenes (E6/E7) plays a key role in tumor progression. E6 are responsible for the transformation and maintenance of the malignancy of cervical cancer cells. Nanobody expressed as “intracellular antibodies” (intrabodies) can target intracellular antigens to hamper their function efficaciously and specifically. In this work, phage-display approach was employed to select the high affinity HPV16E6-specific Nb. After four rounds of biopanning, Nb27, Nb9 andNb22 against E6 were selected from phage library. Nb27 has high affinity and can specifically bind endogenous E6 protein expressed in CaSki and SiHa cells. Notablely, in Nb27 stably expressed cells, CaSki-GFP-Nb27 and SiHa-GFP-Nb27 cells, Nb27 could block E6 entering nucleus and enriched E6 in the cytoplasm, which prevents it from inactivating p53 and leads to the increase of apoptosis. Together our results suggest that nanobody Nb27 may be useful inhibitor for E6 function and be particularly appropriate for the treatment of HPV associated disease.
Keywords - HPV, HPV16, E6, E7, Nanobody