title: Differential tumor cell targeting of anti-HER2 (Herceptin) and anti-CD20 (Mabthera) coupled nanoparticles.
abstract: Two types of antibody-labeled nanoparticles (mAb-NPs) were prepared with the aim to achieve specific tumor targeting. Anti-HER2 and anti-CD20 monoclonal antibodies (mAb) were used as model ligands. Small poly(dl-lactic acid) nanoparticles (PLA NPs) with a mean size of about 170 nm were prepared by the salting out method. Thereafter, the coating of PLA NPs with mAbs was performed in two steps. First, thiol groups (-SH) were introduced on the surface of PLA-NPs by a two-step carbodiimide reaction. The number of -SH groups on the surface of NPs increased from 150 to 400 mmol-SH/mol PLA when cystamine concentrations of 25-1518 mol cystamine/mol PLA were used during the thiolation reaction. In the second step, covalent coupling of antibodies to thiolated NPs (NPs-SH) was obtained via a bifunctional cross-linker, m-maleimidobenzoyl-N-hydroxy-sulfosuccinimide ester (sulfo-MBS). For both mAbs anti-HER2 and anti-CD20, respectively, the number of -SH functions on the NPs had no influence on the amount of mAb coupled to the NPs. Approximately, 295 anti-HER2 and 557 anti-CD20 molecules, respectively, were covalently coupled per nanoparticle. The NPs size after the coupling reactions was about 250 nm. The specific interaction between tumor cells and mAb-NPs was determined by confocal microscopy using two cell lines: SKOV-3 human ovarian cancer cells (overexpressing HER2) and Daudi lymphoma cells (overexpressing CD20). The results showed the selective targeting of mAb-NPs to tumor cells overexpressing the specific antigen. While anti-CD20 labeled NPs (anti-CD20 NPs) bound to and remained at the cellular surface, anti-HER2 labeled NPs (anti-HER2 NPs) were efficiently internalized. The mAb-NPs represent a promising approach to improve the efficacy of NPs in active targeting for cancer therapy while the choice of the antibody-target system defines the fate of the mAb-NPs after their binding to the cells.
authors.affiliation: Department of Pharmaceutics and Biopharmaceutics, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Cirstoiu-Hapca
authors.forename: L
authors.initials: L
authors.lastname: Bossy-Nobs
authors.forename: F
authors.initials: F
authors.lastname: Buchegger
authors.forename: R
authors.initials: R
authors.lastname: Gurny
authors.forename: F
authors.initials: F
authors.lastname: Delie
mesh_terms: D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20 / Q000276:immunology; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000737:chemistry; D045744:Cell Line, Tumor; D003432:Cross-Linking Reagents; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods*; D005260:Female; D006801:Humans; D018796:Immunoconjugates / Q000737:chemistry; D019344:Lactic Acid; D008223:Lymphoma / Q000188:drug therapy; D053758:Nanoparticles / Q000737:chemistry / Q000627:therapeutic use*; D010051:Ovarian Neoplasms / Q000188:drug therapy; D011091:Polyesters; D011108:Polymers; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000276:immunology; D000069283:Rituximab; D013438:Sulfhydryl Compounds; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20; D000970:Antineoplastic Agents; D003432:Cross-Linking Reagents; D004337:Drug Carriers; D018796:Immunoconjugates; D019344:Lactic Acid; D011091:Polyesters; D011108:Polymers; D018719:Erb-b2 Receptor Tyrosine Kinases; D000069283:Rituximab; D013438:Sulfhydryl Compounds; D000068878:Trastuzumab; C033616:poly(lactide)