Sparks Zachary, Wen Yuhan, Hawkins Ian, Lednicky John, Abboud Georges, Nelson Corwin, Driver John P, Chauhan Anuj
Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401, United States.
Department of Animal Sciences, University of Florida, Gainesville, FL 32612, United States.
Eur J Pharm Biopharm. 2024 Sep;202:114388. doi: 10.1016/j.ejpb.2024.114388. Epub 2024 Jun 28.
Influenza vaccines administered as intramuscularly injected inactivated viruses or intranasally administered live-attenuated viruses usually provide short-term protection against influenza infections. Biodegradable particles that provide sustained release of the antigen has been studied as an approach to extend vaccine protection. Here, we investigate sustained release of ultraviolet killed influenza A virus (A/PR/8/34(H1N1)) (kPR8) loaded into poly(D,L-lactic-co-glycolic acid) (PLGA) microparticles. Particles were prepared using the double emulsion method, and polymer molecular weight (MW), polymer hydrophobicity, polymer concentration in the organic phase, and the amount of killed virus were varied to obtain a range of particles. Formulations included PLGA 50:50 (2-6, 7-17 kDa), PLGA 75:25 (4-15 kDa), and 50/50 PLGA 75:25 (4-15 kDa)/PCL (14 kDa). Additionally, NaOH was co-encapsulated in some cases to enhance particle degradation. The structure of the particles was explored by size measurements and electron microscopy. The kPR8 release profiles were measured using hemagglutinin ELISA. The concentration of the polymer (PLGA) in the organic phase and polymer MW significantly influenced virus loading, while polymer MW and co-encapsulation of NaOH modulated the release profiles. Mice receiving a single intramuscular injection of NaOH microparticle-encapsulated kPR8 were partially protected against a lethal influenza challenge 32 weeks post immunization. Microparticle (MP) vaccination induced a gradual increase in PR8-specific IgGs dominated by IgG1 in contrast to the rapid IgG2a-biased response elicited by soluble kPR8 immunization. Our results indicate that vaccine-NaOH co-loaded PLGA particles show potential as a single dose vaccination strategy for extended protection against influenza virus infection.
通过肌肉注射灭活病毒或鼻内接种减毒活病毒方式接种的流感疫苗通常能提供针对流感感染的短期保护。作为一种延长疫苗保护作用的方法，可实现抗原持续释放的可生物降解颗粒已得到研究。在此，我们研究了负载于聚（D，L - 乳酸 - 乙醇酸共聚物）（PLGA）微粒中的经紫外线灭活的甲型流感病毒（A/PR/8/34(H1N1)）（kPR8）的持续释放情况。使用双乳液法制备微粒，并改变聚合物分子量（MW）、聚合物疏水性、有机相中聚合物浓度以及灭活病毒的量，以获得一系列微粒。配方包括PLGA 50:50（2 - 6，7 - 17 kDa）、PLGA 75:25（4 - 15 kDa）以及50/50 PLGA 75:25（4 - 15 kDa）/聚己内酯（PCL）（14 kDa）。此外，在某些情况下共包封氢氧化钠以增强颗粒降解。通过尺寸测量和电子显微镜对颗粒结构进行了探究。使用血凝素酶联免疫吸附测定法测量kPR8释放曲线。有机相中聚合物（PLGA）的浓度和聚合物MW显著影响病毒负载量，而聚合物MW和氢氧化钠的共包封调节了释放曲线。在免疫后32周，接受单次肌肉注射包封有kPR8的氢氧化钠微粒的小鼠受到致死性流感攻击时得到了部分保护。与可溶性kPR8免疫引发的快速偏向IgG2a的反应相反，微粒（MP）疫苗接种诱导了以IgG1为主的PR8特异性IgG逐渐增加。我们的结果表明，共负载疫苗 - 氢氧化钠的PLGA颗粒显示出作为单剂量疫苗接种策略用于延长针对流感病毒感染保护作用的潜力。
