Optimum conditions for efficient phagocytosis of rifampicin-loaded PLGA microspheres by alveolar macrophages.
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.
Hirota
Keiji
K
Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki Noda, Chiba 278-8510, Japan.
Hasegawa
Taizo
T
Hinata
Hideyuki
H
Ito
Fuminori
F
Inagawa
Hiroyuki
H
Kochi
Chie
C
Soma
Gen-Ichiro
G
Makino
Kimiko
K
Terada
Hiroshi
H
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
D004337:Drug Carriers; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D012293:Rifampin