Rhombic organization of microvilli domains found in a cell model of the human intestine

PLoS One. 2018 Jan 10;13(1):e0189970. doi: 10.1371/journal.pone.0189970. eCollection 2018.

Abstract

Symmetry is rarely found on cellular surfaces. An exception is the brush border of microvilli, which are essential for the proper function of transport epithelia. In a healthy intestine, they appear densely packed as a 2D-hexagonal lattice. For in vitro testing of intestinal transport the cell line Caco-2 has been established. As reported by electron microscopy, their microvilli arrange primarily in clusters developing secondly into a 2D-hexagonal lattice. Here, atomic force microscopy (AFM) was employed under aqueous buffer conditions on Caco-2 cells, which were cultivated on permeable filter membranes for optimum differentiation. For analysis, the exact position of each microvillus was detected by computer vision; subsequent Fourier transformation yielded the type of 2D-lattice. It was confirmed, that Caco-2 cells can build a hexagonal lattice of microvilli and form clusters. Moreover, a second type of arrangement was discovered, namely a rhombic lattice, which appeared at sub-maximal densities of microvilli with (29 ± 4) microvilli / μm2. Altogether, the findings indicate the existence of a yet undescribed pattern in cellular organization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / pathology
  • Cell Culture Techniques / instrumentation
  • Cell Line, Tumor
  • Colonic Neoplasms / pathology
  • Enterocytes / ultrastructure*
  • Fourier Analysis
  • Humans
  • Microscopy, Atomic Force
  • Microscopy, Electron, Scanning
  • Microvilli / ultrastructure*

Grants and funding

The authors acknowledge the German Bundesministerium für Bildung für Forschung (BMBF - https://www.bmbf.de/en/research-funding-1411.html) for funding (FKZ 13N11390 to KL and 01DJ13022A to CR) and by the Open Access Publication Funds of the Göttingen University. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The Serend-ip GmbH / nanoAnalytics GmbH provided support in the form of salaries for authors [CR, AK / MS], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.