Document Detail

Kinetic analysis of endocytosis and intracellular fate of liposomes in single macrophages.
MedLine Citation:
PMID:  7775396     Owner:  NLM     Status:  MEDLINE    
Endocytosis and the intracellular fate of liposomes in single mouse peritoneal macrophages were examined kinetically by fluorescence microphotometry. Liposomes labeled with N-(7-nitro-2,1,3-benzoxadiazol-4-yl)phosphatidylethanolamine or containing 8-amino-naphthalene-1,3,6-trisulfonate were promptly incorporated into macrophages on incubation at 37 degrees C, but fluorescence increase caused by hydrolysis of 4-methylumbelliferyl-beta-D-glucoside encapsulated in the liposomes was observed after 30 min of incubation. The fluorescences of calcein and 8-hydroxy-1,3,6-pyrenetrisulfonate (HPTS) in liposomes, which were respectively quenched statically due to high concentration and dynamically by a co-entrapped fluorescence quencher, p-xylene-bis-pyridinium bromide, also increased from 30 min after the start of liposome incorporation, indicating that macrophages require this period for intracellular delivery of liposomes from the cell surface to lysosomes. Measurement of the intraendosomal pH change in a single macrophage at 37 degrees C with liposomes containing a pH-sensitive fluorescent marker, HPTS, showed that the pH value decreased continuously to a constant value of 5.5 in 30-40 min after endocytosis, and this decrease was reversed on addition of NH4Cl, suggesting that acidification of endosomes is not a stepwise reaction and is coupled with delivery of liposomes. These fluorescence microphotometric systems using liposomes containing different fluorescent dyes should be useful for kinetic analyses of the endocytosis and intracellular fate of liposomes in various phagocytes.
T Yoshimura; M Shono; K Imai; K Hong
Related Documents :
7418116 - The interaction of mequitazine with phospholipid model membranes.
16997516 - Multivariate toxicity screening of liposomal formulations on a human buccal cell line.
8287046 - Modification of liposomes by addition of hco60. ii. encapsulation of doxorubicin into l...
16662386 - Aggregation of plant protoplasts by artificial lipid vesicles.
19872456 - Chemical antagonism of ions : i. effect of na-mg and k-mg mixtures on the activity of o...
18460756 - Polyvinyl alcohol-glycine composite membranes: preparation, characterization, drug rele...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of biochemistry     Volume:  117     ISSN:  0021-924X     ISO Abbreviation:  J. Biochem.     Publication Date:  1995 Jan 
Date Detail:
Created Date:  1995-07-07     Completed Date:  1995-07-07     Revised Date:  2007-12-19    
Medline Journal Info:
Nlm Unique ID:  0376600     Medline TA:  J Biochem     Country:  JAPAN    
Other Details:
Languages:  eng     Pagination:  34-41     Citation Subset:  IM    
Institute for Enzyme Research, University of Tokushima.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Drug Carriers
Endocytosis / physiology*
Fluorescent Dyes / administration & dosage*
Fluorometry / instrumentation*
Macrophages, Peritoneal / physiology*
Mice, Inbred Strains
Reg. No./Substance:
0/Drug Carriers; 0/Fluorescent Dyes; 0/Liposomes

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Role of Lys108 in the enzymatic activity of RNase Rh from Rhizopus niveus.
Next Document:  Apparent antibacterial activity of catalase: role of lipid hydroperoxide contamination.