PLGA-PEG-PLGA from PolySciTech used in development of Rapamycin delivery system

 

Rapamycin is a macrolide exhibiting potent antitumor and immunosuppressive activity. Unfortunately it has quick clearance and lacks targeted delivery for many applications. Recently, researchers used PLGA-PEG-PLGA (AK016) from PolySciTech (www.polyscitech.com) to create rapamycin-loaded nanoparticles inside of microspheres. Researchers tested the application of this delivery system towards the treatment of hemangiomas. This research holds promise to provide for improved application of rapamycin against a variety of disease states. Read more: Li, Haitao, Xin Wang, Xiaonan Guo, Qingkun Wan, Yunfei Teng, and Jianyong Liu. "Development of rapamycin-encapsulated exosome-mimetic nanoparticles-in-PLGA microspheres for treatment of hemangiomas." Biomedicine & Pharmacotherapy 148 (2022): 112737. https://www.sciencedirect.com/science/article/pii/S0753332222001251

“Highlights: Rapamycin-encapsulated exosome-mimetic nanoparticles-in-PLGA microspheres (RNM) show slow-release of rapamycin. RNM achieved superior therapeutic efficacy against hemangiomas over rapamycin. The therapeutic efficacy of RNM was attributed to its sustained release and suppression efficacy against HemSCs. Abstract: We have previously developed several kinds of rapamycin-encapsulated nanoparticles to achieve sustained release of rapamycin to treat hemangioma. However, lack of intrinsic targeting and easy clearance by the immune system are major hurdles that artificial fabricated nanoparticles must overcome. We constructed rapamycin-encapsulated macrophage-derived exosomes mimic nanoparticles-in-microspheres (RNM), to achieve the goal of continuous targeted therapy of hemangiomas. The rapamycin-encapsulated exosome mimic nanoparticles (RN) were firstly prepared by the extrusion-based method from the U937 cells (the human macrophage cell line). After then, RN was encapsulated with PLGA (poly(lactic-co-glycolic acid)) microspheres to obtain RNM. The release profile, targeting activity, and biological activity of RN and RNM were investigated on hemangioma stem cells (HemSCs). RN has a size of 100 nm in diameter, with a rapamycin encapsulation efficacy (EE) of 83%. The prepared microspheres RNM have a particle size of ~30 µm), and the drug EE of RNM is 34%. The sustained release of RNM can remarkably be achieved for 40 days. As expected, RN and RNM showed effective inhibition of cellular proliferation, significant cellular apoptosis, and remarkable repressed expression of angiogenesis factors in HemSCs. Our results showed that RNM is an effective approach for prolonged and effective delivery of rapamycin to hemangiomas.”