Purpose: In this study, a double emulsion method for complexing plasmids with stearyl polyethylenimine (stPEI) as the core to form human serum albumin (HSA) (plasmid/stPEI/HSA) nanoparticles (NPs) was developed for gene delivery by non-covalently binding onto plasmid/stPEI/HSA nanoparticles with CRISPR/Cas9 or siRNA, which disrupts or silences the expression of programmed cell death ligand-1 (PD-L1) for immunotherapy. Materials and methods: Chemically synthesized stearyl-polyethyenimine (stPEI)/ plasmids /HSA nanoparticles were maded by double emulsion method. They were characterized by dynamic light scattering (DLS), transmission electron microscope and also evaluated by in vitro study on CT 26 cells. Results: stPEI was synthesized by an N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC)–N-hydroxysuccinimide (NHS) reaction, and we found that the degree of substitution was ~1.0 when the ratio of PEI to stearic acid was 1:7 in the reaction. Then, two sgRNA sequences were selected and evaluated for their ability to knock out PD-L1 by decreasing its expression by about 20%. Based on the trend of particle size/zeta potential values as a function of ratio, F25P1 containing 25 µg of plasmid/stPEI/HSA NPs noncovalently bound to 1 µg plasmids via charge–charge interactions was found to be optimal. Its particle size was about 202.7±4.5 nm, and zeta potential was 12.60±0.15 mV. In an in vitro study, these NPs showed little cytotoxicity but high cellular uptake. Moreover, they revealed the potential for transfection and PD-L1 knockout in an in vitro cell model. Furthermore, F25P1S0.5 containing 25 µg of plasmid/stPEI/HSA NPs noncovalently bound to 1 µg of plasmids and 0.5 µg siRNA was prepared to simultaneously deliver plasmids and siRNA. An in vitro study demonstrated that the siRNA did not interfere with the transfection of plasmids and showed a high-transfection efficiency with a synergistic effect on inhibition of PD-L1 expression by 21.95%. Conclusion: The plasmids/stPEI/HSA NPs could be a promising tool for gene delivery and improved immunotherapy.

The purpose of this study was to develop poloxamer (P407)-based in-situ thermogellable hydrogels with reducing concentration of P407 by adding hypromellose (HPMC) and with enhancing mucoadhesion of resulting hydrogels by adding hyaluronic acid (HA) for prolonging ocular delivery of hydroxypropyl-β-cyclodextrin (HPβCD)-solubilized testosterone (TES). Results demonstrated that 0.5% TES solution was successfully solubilized with adding 10% HPβCD. Non-gellable 13% P407 sol became in-situ gellable with adding 2.0-2.5% HPMC and mucoadhesibility was further imporved with adding 0.3% HA-L (low MW) or HA-H (high MW). Optimized 0.5% HPβCD-solubilized TES P407-based thermogellable hydrogels with enhancement of mucoadhesion for prolonging ocular delivery comprised 13% P407, 2.5% HPMC, and 0.3% HA-L or HA-H. Furthermore, rheological measurements under simulated eye blinking confirmed that non-thixotropic properties of optimized hydrogels could be spreaded evenly and retain a greater amount of drug-loaded hydrogels on the ocular surface for a longer period to prolong drug delivery. Compared with conventional eye drops, the prolonged residence time of optimized hydrogels from ex vivo and in vivo studies were observed, indicating relationships between rheological properties and in vivo performances. It was concluded that P407-based thermosensitive hydrogels with reducing concentration of P407 and enhancing mucoadhesion was successfully formulated by adding 2.5% HPMC and 0.3% HA in 13% P407 for potentially accomplishing effective clinical treatment of DED.

Regarding compliance and minimization of side effects of nilotinib therapy, there is a medical need to have a gastroretentive drug delivery system (GRDDS) to enhance the oral bioavailability that is able to administer an optimal dose in a quaque die (QD) or daily manner. In this study, the influence on a swelling and floating (sf) GRDDS composed of a polymeric excipient (HPMC 90SH 100K, HEC 250HHX, or PEO 7000K) and Kollidon^® SR was examined. Results demonstrated that PEO 7000K/Kollidon SR (P/K) at a 7/3 ratio was determined to be a basic GRDDS formulation with optimal swelling and floating abilities. MCC PH102 or HPC_sssl,SFP was further added at a 50% content to this basic formulation to increase the tablet hardness and release all of the drug within 24 h. Also, the caplet form and capsule form containing the same formulation demonstrated higher hardness for the former and enhanced floating ability for the latter. A pharmacokinetic study on rabbits with pH values in stomach and intestine similar to human confirmed that the enhanced oral bioavailability ranged from 2.65–8.39-fold with respect to Tasigna, a commercially available form of nilotinib. In conclusion, the multiple of enhancement of the oral bioavailability of nilotinib with sfGRDDS could offer a pharmacokinetic profile with therapeutic effectiveness for the QD administration of a reasonable dose of nilotinib, thereby increasing compliance and minimizing side effects.