Lectin-mediated bioadhesion: binding characteristics of plant lectins on the enterocyte-like cell lines Caco-2, HT-29 and HCT-8.
In order to take advantage of the biorecognition between lectins and specific carbohydrates for targeted drug delivery, fluorescein-labelled lectins of different carbohydrate specificities were screened for binding to human colorectal carcinoma cell lines by flow cytometry and confocal microscopy. The lectin-binding rate increased as follows: Dolichos biflorus agglutinin, DBA<peanut agglutinin, PNA<Lens culinaris agglutinin, LCA<Solanum tuberosum lectin, STL<Ulex europaeus isoagglutinin I, UEA-I<wheat germ agglutinin, WGA (Caco-2); PNA<UEA-I<WGA (HT-29); DBA<UEA-I<WGA (HCT-8), thus reflecting the glycosylation pattern of the cells. Compared to the BSA-binding capacity of the cells, the extent of nonspecific binding was strongly dependent on the type of cell line and lectin under investigation being lower than 2% in the case of WGA, STL and UEA-I/Caco-2 and HT-29 cells. Whereas 50% of DBA was bound nonspecifically to Caco-2 cells, the interactions DBA/HCT-8 and PNA/HT-29 were due to nonspecific binding. By competitive inhibition of lectin-adhesion to the cells upon addition of the complementary carbohydrate, specificity of lectin-binding was confirmed except for the interaction of DBA/HCT-8 and PNA/HT-29. Following on from this work, we consider WGA-, STL- and UEA-I-mediated drug delivery to be a promising approach for peroral bioadhesive formulations adhering to absorptive enterocytes.
Gabor
F
F
Institute of Pharmaceutical Technology, the University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria. franz.gabor@univie.ac.at
Stangl
M
M
Wirth
M
M
D018938:Caco-2 Cells; D002448:Cell Adhesion; D019073:HT29 Cells; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000166:cytology; D037102:Lectins / Q000378:metabolism*; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D037121:Plant Lectins; D010944:Plants / Q000378:metabolism; D011485:Protein Binding; D014407:Tumor Cells, Cultured
D037102:Lectins; D037121:Plant Lectins