title: Optimum conditions for efficient phagocytosis of rifampicin-loaded PLGA microspheres by alveolar macrophages.
abstract: We examined the phagocytic activities of alveolar macrophages (NR8383 cells) toward poly(lactic-co-glycolic) acid (PLGA) microspheres (MS) loaded with the anti-tuberculosis agent rifampicin (RFP), the sizes of which were between 1 microm and 10 microm. We found that 1) the phagocytosis was dependent greatly on the particle size and the number of particles added; 2) macrophages phagocytosed considerably the PLGA microspheres loaded with RFP, the diameter of which was between 1 microm and 6 microm, but took up few 10-microm particles; 3) the population of the macrophages that phagocytosed 1-microm or 3-microm particles was larger than that of those phagocytosed 6- or 10-microm particles; 4) a considerable population of macrophages were not able to phagocytose even the 1- and 3-microm particles; 5) the most efficient deliveries of RFP into each macrophage cell and a large population of macrophages were achieved by the phagocytosis of 3-microm particles; and 6) phagocytosis did not affect macrophage viability in 4 h after the start of phagocytosis.
authors.affiliation: Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki Noda, Chiba 278-8510, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Hirota
authors.forename: Taizo
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Hinata
authors.forename: Fuminori
authors.initials: F
authors.lastname: Ito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inagawa
authors.forename: Chie
authors.initials: C
authors.lastname: Kochi
authors.forename: Gen-Ichiro
authors.initials: G
authors.lastname: Soma
authors.forename: Kimiko
authors.initials: K
authors.lastname: Makino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Terada
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004337:Drug Carriers; D019344:Lactic Acid / Q000008:administration & dosage* / Q000493:pharmacokinetics; D016676:Macrophages, Alveolar / Q000187:drug effects* / Q000378:metabolism; D008863:Microspheres; D010587:Phagocytosis / Q000187:drug effects* / Q000502:physiology; D011100:Polyglycolic Acid / Q000008:administration & dosage* / Q000493:pharmacokinetics; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000008:administration & dosage* / Q000493:pharmacokinetics; D051381:Rats; D012293:Rifampin / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D004337:Drug Carriers; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D012293:Rifampin