Multiple presentation of Scfv800E6 on silica nanospheres enhances targeting efficiency toward HER-2 receptor in breast cancer cells.
Spherical silica nanoparticles (SNP) have been synthesized and functionalized with anti-HER-2 scFv800E6 antibody by both localized histidine-tag recognition, leading to an oriented protein ligation, and glutaraldehyde cross-linking, exploiting a statistical reactivity of lysine amine groups in the primary sequence of the molecule. The targeting efficiency of nanocomplexes in comparison with free scFv was evaluated by flow cytometry using a HER-2 antigen-positive MCF-7 breast cancer cell line, exhibiting a 4-fold increase in scFv binding efficacy, close to the affinity of intact anti-HER-2 monoclonal antibody, which suggests the effectiveness of presenting multiple scFv molecules on nanoparticles in improving antigen recognition. Unexpectedly, the conjugation method did not affect the binding efficacy of scFv, suggesting a structural role of lysines in the scFv molecule. Confocal laser scanning microscopy confirmed the binding of nanocomplexes to HER-2 and also provided evidence of their localization at the cell surface.
Dipartimento di Scienze Cliniche Luigi Sacco, Università di Milano, Ospedale L. Sacco, Via G.B. Grassi 74, Milan, Italy.
Serena
S
Mazzucchelli
Paolo
P
Verderio
Silvia
S
Sommaruga
Miriam
M
Colombo
Agnese
A
Salvadè
Fabio
F
Corsi
Patrizia
P
Galeffi
Paolo
P
Tortora
Davide
D
Prosperi
D000818:Animals; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D015394:Molecular Structure; D054118:Nanospheres / Q000737:chemistry* / Q000648:ultrastructure; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D012822:Silicon Dioxide / Q000737:chemistry*; D057127:Single-Chain Antibodies / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use
D018719:Erb-b2 Receptor Tyrosine Kinases; D012822:Silicon Dioxide; D057127:Single-Chain Antibodies