Establishment Carrier Erythrocytes Drug Delivery Systems And Evaluation Of The Vinorelbine-loaded Erythrocytes In Vitro

BackgroundVinorelbine is a kind of semisynthetic vinca alkaloids antitumor drugs. It is used as first-line treatment drugs of advanced non-small cell lung cancer (NSCLC, non-small cell lung cancer). And it is also widely used in metastatic breast cancer, refractory lymphoma, ovarian cancer and so on. Drug delivery systems have significant clinical impact as they promise sustained systemic delivery and better targeting. It is the most effective way to reduce side effect, decrease drug dose and improve drug efficacy. Carrier erythrocyte has a lot of advantages, such as biocompatibility, biodegradability, long-circulation time and so on. But most of the studies of carrier erythrocytes stay in preclinical because of the drug controlled release ability.Objectives:1?To demonstrate the feasibility of establishing carrier erythrocytes by the technology as described in the literatures. To find the best drug loading condition and calculate the drug loading ratio.2?To evaluate the damage to the structure and function of erythrocyte membrane during drug loading.To evaluate the low temperature storage stability and sustained-release ability of vinorelbine-loaded erythrocyte.3?To demonstrate tumor cell proliferation inhibition of vinorelbine-loaded erythrocyte by human lung adenocarcinoma cell A549 in vitro.Method:1?Establishing carrier erythrocytes by a modified hypotonic preswelling technique as described in the literatures. Calculating the drug loading ratio by two different methods to find the best vinorelbine concentration and the optimal action time.2?Investigating the modified hypotonic preswelling technique by comparing the morphology and osmotic fragility of erythrocyte before and after loading drug. Investigating the low temperature storage stability of vinorelbine-loaded erythrocytes by testing the vinorelbine concentration of the supernatant and observing the erythrocyte morphology everyday during vinorelbine-loaded erythrocytes were storaged in PBS at 4?. Draw the "Time-Concentration" diagram to investage the sustained-release ability of vinorelbine-loaded erythrocytes.3?Cell proliferation inhibition was measured by MTT to compare the cytotoxicity of vinorelbine -loaded erythrocytes and free vinorelbine.Results:1?The modified hypotonic preswelling technique is a effective method to establish carrier erythrocytes and vinrelbine-loaded erythrocytes with the drug loading ratio approximate 70.92%.2?There are no obviously distinguish of morphology and osmotic fragility between carrier erythrocyte and vinorelbine-loaded erythrocyte. Carrier erythrocytes can release vinorelbine sustainably, and approaching 100% vinorelbine was released from carrier erythrocytes at 48h.3?When the dose of vinorelbine at 0.0125,0.025 g/l, vinorelbine-loaded erythrocytes appeared better cell proliferation inhibition than free vinorelbine when incubated with A549 for 48h.Conclusion:1?The modified hypotonic preswelling technique can effectively establish the vinorelbine-loaded erythrocytes with the drug loading ratio approximate 70.92%, and without any damage on the structure and function of the erythrocyte.2?Vinorelbine-loaded erythrocytes can be storaged in PBS at 4? steady about 5 days, and vinorelbine can be released approaching 100% when vinorelbine-loaded erythrocytes were storaged in PBS at 37? for 48h.3?Vinorelbine-loaded erythrocytes appeared better cell proliferation inhibition than free vinorelbine on human lung adenocarcinoma cell in vitro, and the cytotoxicity was increased with time longer.