Production of HPV16 capsid proteins in suspension cultures of human epithelial cells

Abstract

Human papillomavirus (HPV) infection is a leading cause of morbidity and mortality in women worldwide. The virus is associated with benign warts and a broad spectrum of malignancies, including cervical cancer, considered a disease of high clinical relevance, especially in developing countries. In this study we developed the production of recombinant proteins HPV16 L1 and HPV16 L2 in human cells in suspension (293-F), which were transiently co-transfected with the pUF3/L1h and pUF3/L2h vectors. Expressions of recombinant HPV16 L1 and L2 capsid proteins was detected by laser scanning confocal microscopy and flow cytometry. Both proteins were identified intracellularly in the nucleus and cytoplasm of cells. The presence of these heterologous proteins and VLPs formation were detected by transmission electron microscopy (TEM) through colloidal gold immunolabeling and negative staining. Cell extracts containing recombinant proteins were purified by affinity chromatography and immunization of Balb/c mice with the formulation HPV16 L1/L2 VLPs containing adjuvant was able to induce higher titer of anti-HPV16 L1, when compared to HPV16 L2 antibodies by indirect ELISA assay. These data indicate that transient expression in 293-F cells was efficiently established. The results are promising for obtain recombinant proteins of the HPV capsid for future studies involving human papillomavirus, as well as to contribute for the development of other vaccine strategies for prevention against HPV.

Human papillomavirus infection associated with cervical cancer and other malignancies

“…According to oncogenic potential thirteen high-risk HPV types are classified, such as HPVs 16,18,31,33,35,39,45,51,52,56,58,59, considered carcinogenic and sixty-eight as probably carcinogenic. The HPV types 26,30,34,53,66,67,69,70,73, 82 e 85 are considered possibly carcinogenic [27].…”

“…Lots approaches have been used for the development of prophylactic vaccines against HPV, based on recombinant proteins expressed in distinct cellular systems, such as mammalian, insect, yeast, and bacterial cells [69][70][71][72][73].…”