Targeted lipid-coated nanoparticles: Delivery of tumor necrosis factor-functionalized particles to tumor cells

Abstract

Polymeric nanoparticles displaying tumor necrosis factor on their surface (TNF nanocytes) are useful carrier systems capable of mimicking the bioactivity of membrane-bound TNF. Thus, TNF nanocytes are potent activators of TNF receptor 1 and 2 leading to a striking enhancement of apoptosis. However, in vivo applications are hampered by potential systemic toxicity. Here, using TNF nanocytes as a model system, we developed a procedure to generate targeted lipid-coated particles (TLP) in which TNF activity is shielded. The TLPs generated here are composed of an inner single-chain TNF (scTNF)-functionalized, polymeric nanoparticle core surrounded by a lipid coat endowed with polyethylene glycol (PEG) for sterical stabilization and a single-chain Fv (scFv) fragment for targeting. Using a scFv directed against the tumor stroma marker fibroblast activation protein (FAP) we show that TLP and scTNF-TLP specifically bind to FAP-expressing, but not to FAP-negative cells. Lipid coating strongly reduced nonspecific binding of particles and scTNF-mediated cytotoxicity towards FAP-negative cells. In contrast, an increased cytotoxicity of TLP was observed for FAP-positive cells. Thus, through liposome encapsulation, nanoparticles carrying bioactive molecules, which are subject to nonselective uptake and activity towards various cells and tissues, can be converted into target cell-specific composite particles exhibiting a selective activity towards antigen-positive target cells. Besides safe and targeted delivery of death ligands such as TNF, TLP should be suitable for various diagnostic and therapeutic applications, which benefit from a targeted delivery of reagents embedded into the particle core or displayed on the core particle surface.

Targeting melanoma with immunoliposomes coupled to anti-MAGE A1 TCR-like single-chain antibody

“…34,37,41,42 Briefly, all lipids were mixed in a round bottom flask and dissolved in chloroform:methanol (9:1 v/v). A thin and uniform lipid film was obtained by evaporating the solvents under pressure for 30 minutes at 42°C.…”

“…The mixture was then extruded 17-20 times under pressure through a series of polycarbonate filters ranging from 200 to 50 nm to obtain a uniform suspension of particles. Size and polydispersity index (PDI) 31,34,41,43 were determined by dynamic light scattering 43 on a Zetasizer ® Nano ZS (Malvern Instruments, Worcestershire, UK). Liposomes were subjected to Rouser phosphate assay 44 where phospholipid was determined and a total lipid amount was calculated after cholesterol correction.…”

From polymeric particles to multifunctional nanocapsules for biomedical applications using the miniemulsion process

“…8). 109 Thus, TNF nanocytes are potent activators of TNF receptors 1 and 2 leading to a striking enhancement of apoptosis. However, in vivo applications are hampered by potential systemic toxicity.…”

The use of single chain Fv as targeting agents for immunoliposomes: an update on immunoliposomal drugs for cancer treatment

“…Recently, Noble et al demonstrated that immunoliposomal vincristine or vinblastine targeted by an anti-HER2 scFv were more efficacious than their respective non-targeted formulations or the free drug, in an animal model of breast cancer [86]. Messerschmidt et al demonstrated a new way of delivering tumor necrosis factor (TNF) to tumor cells expressing the fibroblast activation protein (FAP), using TNF-functionalized lipidic nanoparticles that are targeted by an anti-FAP scFv [95]. Hence, data are emerging to demonstrate that targeting of liposomal drugs by scFv results in increased therapeutic effects over non-targeted liposomal drugs and suggest that scFv is a viable alternative to Fab′ or mAb.…”