PMID- 34169366 OWN - NLM STAT- MEDLINE DCOM- 20210705 LR - 20220716 IS - 1530-9932 (Electronic) IS - 1530-9932 (Linking) VI - 22 IP - 5 DP - 2021 Jun 24 TI - Formulation and In Vitro Characterization of PLGA/PLGA-PEG Nanoparticles Loaded with Murine Granulocyte-Macrophage Colony-Stimulating Factor. PG - 191 LID - 10.1208/s12249-021-02049-z [doi] AB - Granulocyte-macrophage colony-stimulating factor (GM-CSF) has demonstrated notable clinical activity in cancer immunotherapy, but it is limited by systemic toxicities, poor bioavailability, rapid clearance, and instability in vivo. Nanoparticles (NPs) may overcome these limitations and provide a mechanism for passive targeting of tumors. This study aimed to develop GM-CSF-loaded PLGA/PLGA-PEG NPs and evaluate them in vitro as a potential candidate for in vivo administration. NPs were created by a phase-separation technique that did not require toxic/protein-denaturing solvents or harsh agitation techniques and encapsulated GM-CSF in a more stable precipitated form. NP sizes were within 200 nm for enhanced permeability and retention (EPR) effect with negative zeta potentials, spherical morphology, and high entrapment efficiencies. The optimal formulation was identified by sustained release of approximately 70% of loaded GM-CSF over 24 h, alongside an average size of 143 +/- 35 nm and entrapment efficiency of 84 +/- 5%. These NPs were successfully freeze-dried in 5% (w/v) hydroxypropyl-beta-cyclodextrin for long-term storage and further characterized. Bioactivity of released GM-CSF was determined by observing GM-CSF receptor activation on murine monocytes and remained fully intact. NPs were not cytotoxic to murine bone marrow-derived macrophages (BMDMs) at concentrations up to 1 mg/mL as determined by MTT and trypan blue exclusion assays. Lastly, NP components generated no significant transcription of inflammation-regulating genes from BMDMs compared to IFNgamma+LPS "M1" controls. This report lays the preliminary groundwork to validate in vivo studies with GM-CSF-loaded PLGA/PEG-PLGA NPs for tumor immunomodulation. Overall, these data suggest that in vivo delivery will be well tolerated. FAU - Mihalik, Nicole E AU - Mihalik NE AD - Department of Microbiology, Immunology, and Cell Biology, West Virginia University, PO Box 9177, Morgantown, West Virginia, 26506-9177, USA. AD - West Virginia University Cancer Institute, PO Box 9530, Morgantown, West Virginia, 26506, USA. FAU - Wen, Sijin AU - Wen S AD - West Virginia University Cancer Institute, PO Box 9530, Morgantown, West Virginia, 26506, USA. AD - West Virginia Clinical and Translational Science Institute, Morgantown, West Virginia, 26506, USA. AD - West Virginia University School of Public Health Department of Biostatistics, Morgantown, West Virginia, 26506, USA. FAU - Driesschaert, Benoit AU - Driesschaert B AD - West Virginia University Cancer Institute, PO Box 9530, Morgantown, West Virginia, 26506, USA. Benoit.driesschaert@hsc.wvu.edu. AD - West Virginia Clinical and Translational Science Institute, Morgantown, West Virginia, 26506, USA. Benoit.driesschaert@hsc.wvu.edu. AD - Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia, 26506, USA. Benoit.driesschaert@hsc.wvu.edu. AD - In Vivo Multifunctional Magnetic Resonance (IMMR) center, Morgantown, West Virginia, 26506, USA. Benoit.driesschaert@hsc.wvu.edu. FAU - Eubank, Timothy D AU - Eubank TD AD - Department of Microbiology, Immunology, and Cell Biology, West Virginia University, PO Box 9177, Morgantown, West Virginia, 26506-9177, USA. tdeubank@hsc.wvu.edu. AD - West Virginia University Cancer Institute, PO Box 9530, Morgantown, West Virginia, 26506, USA. tdeubank@hsc.wvu.edu. AD - West Virginia Clinical and Translational Science Institute, Morgantown, West Virginia, 26506, USA. tdeubank@hsc.wvu.edu. AD - In Vivo Multifunctional Magnetic Resonance (IMMR) center, Morgantown, West Virginia, 26506, USA. tdeubank@hsc.wvu.edu. LA - eng GR - R00 EB023990/EB/NIBIB NIH HHS/United States GR - T32 GM133369/GM/NIGMS NIH HHS/United States GR - R21 EB028553/EB/NIBIB NIH HHS/United States GR - U54 GM104942/GM/NIGMS NIH HHS/United States GR - P20 GM121322/GM/NIGMS NIH HHS/United States GR - R01 CA192064/CA/NCI NIH HHS/United States GR - P20 GM103434/GM/NIGMS NIH HHS/United States GR - S10 OD016165/OD/NIH HHS/United States GR - R01 CA194013/CA/NCI NIH HHS/United States GR - P20 GM109098/GM/NIGMS NIH HHS/United States PT - Journal Article DEP - 20210624 PL - United States TA - AAPS PharmSciTech JT - AAPS PharmSciTech JID - 100960111 RN - 0 (Antineoplastic Agents) RN - 0 (Polyesters) RN - 0 (polyethylene glycol-poly(lactide-co-glycolide)) RN - 3WJQ0SDW1A (Polyethylene Glycols) RN - 83869-56-1 (Granulocyte-Macrophage Colony-Stimulating Factor) SB - IM MH - Animals MH - Antineoplastic Agents/administration & dosage/chemical synthesis MH - Cell Survival/drug effects/physiology MH - Dose-Response Relationship, Drug MH - Drug Compounding MH - Female MH - Granulocyte-Macrophage Colony-Stimulating Factor/administration & dosage/*chemical synthesis/pharmacokinetics MH - Humans MH - Macrophages/*drug effects/metabolism MH - Male MH - Mice MH - Mice, Inbred C57BL MH - Nanoparticles/administration & dosage/*chemistry MH - Neoplasms/drug therapy/metabolism MH - Polyesters/administration & dosage/*chemical synthesis/pharmacokinetics MH - Polyethylene Glycols/administration & dosage/*chemical synthesis/pharmacokinetics PMC - PMC8361900 MID - NIHMS1726543 OTO - NOTNLM OT - GM-CSF OT - PLGA-PEG OT - macrophages OT - nanoparticles OT - phase separation COIS- The authors declare no potential conflicts of interest. EDAT- 2021/06/26 06:00 MHDA- 2021/07/06 06:00 PMCR- 2022/06/24 CRDT- 2021/06/25 07:00 PHST- 2021/02/04 00:00 [received] PHST- 2021/05/11 00:00 [accepted] PHST- 2021/06/25 07:00 [entrez] PHST- 2021/06/26 06:00 [pubmed] PHST- 2021/07/06 06:00 [medline] PHST- 2022/06/24 00:00 [pmc-release] AID - 10.1208/s12249-021-02049-z [pii] AID - 10.1208/s12249-021-02049-z [doi] PST - epublish SO - AAPS PharmSciTech. 2021 Jun 24;22(5):191. doi: 10.1208/s12249-021-02049-z.