Intracellular scFvs against the viral E6 oncoprotein provoke apoptosis in human papillomavirus-positive cancer cells.
The E6 protein of human papillomavirus type 16 (16E6) is involved in the tumorigenesis of human cervical cells by targeting numerous cellular proteins. We have designed a strategy for neutralizing 16E6 based on the intracellular expression of single-chain Fv antibodies (scFvs) specific to 16E6. Recombinant adenovirus vectors were constructed to allow expression of two 16E6-binding scFvs and one 16E6-non-binding scFv in HPV16-positive and -negative cells. Expression of the scFvs provoked two types of effects: (i) inhibition of proliferation of all cell lines tested, this aspecific toxicity being likely due to the aggregation of unfolded scFvs; and (ii) apoptosis observed only in HPV16-positive cervical cancer cell lines after expression of 16E6-binding scFvs, this specific effect being proportional to the intracellular solubility of the scFvs. These data demonstrate the feasibility of intracellular immunization with anti-16E6 scFvs and highlight the importance of the solubility of the intracellular antibodies.
UMR 7175-LC1, CNRS, Université Louis Pasteur (Strasbourg I), ESBS, Boulevard Sébastien Brant, BP 10413, 67412 Illkirch Cedex, France.
Magali
M
Lagrange
Charlotte
C
Boulade-Ladame
Laurent
L
Mailly
Etienne
E
Weiss
Georges
G
Orfanoudakis
François
F
Deryckere
D000256:Adenoviridae / Q000235:genetics; D017209:Apoptosis; D045744:Cell Line, Tumor; D002472:Cell Transformation, Viral; D004926:Escherichia coli; D005260:Female; D016679:Genome, Viral; D052162:Human papillomavirus 16 / Q000502:physiology*; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000276:immunology*; D009856:Oncogene Proteins, Viral / Q000276:immunology*; D012097:Repressor Proteins / Q000276:immunology*; D002583:Uterine Cervical Neoplasms / Q000473:pathology* / Q000821:virology*
C068651:E6 protein, Human papillomavirus type 16; D007135:Immunoglobulin Variable Region; D009856:Oncogene Proteins, Viral; D012097:Repressor Proteins