2Faculty of Veterinary Medicine, Institute of Physiological Chemistry, Ludwig-Maximilians-University, Veterinärstr. 13, D-80539 Munich, Germany
* To whom correspondence should be addressed.
Received December 27, 2017; Revision received February 9, 2018
Galectins are involved in various biological processes, e.g. cell–cell and cell–matrix adhesion and the transmission of cellular signals. Despite the diversity of functions, little is known about the nature of their physiological cognate ligands on the cell surface and the localization of galectins in the glycocalyx, although this information is important for understanding the functional activity of galectins. In this work, localization of endogenous and exogenously loaded galectins in the glycocalyx was studied. The following main conclusions are drawn: 1) galectins are not evenly distributed within the glycocalyx, they are accumulated in patches. Patching is not the result of a cross-linking of cellular glycans by galectins. Instead, patch-wise localization is the consequence of irregular distribution of glycans forming the glycocalyx; 2) galectins are accumulated in the inner zone of the glycocalyx rather than at its outer face or directly in vicinity of the cell membrane; 3) patches are not associated with cell rafts.
KEY WORDS: galectins, glycans, glycocalyx, mammalian cell