Delivery of liposomes into cultured KB cells via folate receptor-mediated endocytosis

Robert J. Lee, Philip S. Low

Research output: Contribution to journalArticlepeer-review

654 Scopus citations


Folic acid was covalently conjugated to 66-nm liposomes via spacers of various lengths in an attempt to target the liposomes to KB cells expressing folate receptors. Spacers of short and intermediate lengths were unable to mediate association of folate-conjugated liposomes with receptor-bearing cells, however, use of a 250 Å polyethyleneglycol spacer (PEG, M(r) ~3350) permitted avid uptake of the liposomes at ~2.5 x 105 sites/cell. The binding of folate-PEG liposomes to KB cells could be competitively inhibited by excess free folate or by antiserum against the folate receptor, demonstrating the interaction is mediated by the cell surface folate-binding protein. Following binding, cell-associated folate-PEG liposomes were internalized by folate-receptor-mediated endocytosis at 37 °C but not at 4 °C. These folate-PEG liposomes show potential for delivering large quantities of low molecular weight compounds non-destructively into folate receptor-bearing cells.

Original languageEnglish (US)
Pages (from-to)3198-3204
Number of pages7
JournalJournal of Biological Chemistry
Issue number5
StatePublished - Feb 4 1994

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Delivery of liposomes into cultured KB cells via folate receptor-mediated endocytosis'. Together they form a unique fingerprint.

Cite this