Membrane nanostructures are an important factor in the interaction of cells with their surroundings
The functions, development and migration of cells in different environments are associated with a change in their form. One of the mechanisms on which these processes are based is the formation of membrane micro- and nanostructures.
Authors: Miha Fošnarič, Veronika Kralj-Iglič, Aleš Iglič, Samo Penič, Brian R. Graziano, Jason P. Town, Tamas L. Nagy, Nir Gov, Alba Diz-Muñoz, Orion D. Weiner
The development of experimental techniques and mathematical modelling led to the finding that biological membranes are often organised in the form of very tiny structures (nanostructures). The membranes of cells can form tiny outgrowths that are involved in how cells attach to a surface, how they orient in this and in what direction they move. But how this interaction progresses has not yet been fully researched. Researchers from the University of Ljubljana Faculty of Health Sciences (Miha Fošnarič and Veronika Kralj-Iglič), Faculty of Electrical Engineering (Aleš Iglič and Samo Penič) and associates from abroad (Brian R. Graziano, Jason P. Town, Tamas L. Nagy, Nir Gov, Alba Diz-Muñoz and Orion D. Weiner) recently used the tiny membrane protrusions to propose an explanation of the polarisation (directed distribution of components) of neutrophils (a type of white blood cells involved in immune response). For this purpose they formulated software using Monte Carlo method to simulate active cell membrane structures in search for stationary configurations. The phenomena of interaction of cells with surfaces are important in procedures in pharmacy, medicine and the food industry, where samples obtained from living mechanisms come into contact with laboratory materials.
Membrane protrusions can break off from a cell and become freely mobile extracellular micro- and nanovesicles. These have become interesting as a material for diagnostics and therapy. Several procedures have been created for obtaining them from various fluids (e.g. from blood). Adhesion of membrane nanostructures to the surfaces of laboratory tubes and tips is a mechanism whereby nanovesicles are likely being lost. Members of the research group Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana (Veronika Kralj-Iglič and Roman Štukelj) collaborated with colleagues from the Jožef Stefan Institute (Ita Junkar, Miran Mozetič and Rok Zaplotnik) to introduce an improvement of the procedure by treating surfaces with ionic plasma. The work was protected this year with a European patent.
Source: Graziano R. B:, Town P. J., Nagy L. T., Fošnarič M., Penič S., Iglič A., Kralj-Iglič V., Gov N., Diz-Muñoz A., Weiner O. D. Cell confinement reveals a branched-acting independent circuit for neutrophil polarity, Plos Biol, 17 (2019):e3000457.
Junkar I., Kralj-Iglič V., Štukelj R., Zaplotnik R., Mozetič M. (2019) Method for treatment of tools and tools used for isolation of microvesicles, nanovescicles or exsomes. European Patent No. 3185921B1.
The membranes of cells form tiny protrusions with which they can communicate with their surroundings (left). Treatment of surface with ion plasma (middle) changes its landscape and in this way we can influence the interaction and movement of cells over the surface (right).
Image source: Unpublished results of the authors’ work