Topographical control of cell behaviour. I. Simple step cues

Area of Science:

• Cell Biology
• Biophysics
• Tissue Engineering

Background:

• The microelectronics industry's photolithographic techniques enable the creation of patterned plastic substrata.
• Investigating contact guidance of animal tissue cells requires controlled topographical environments.

Purpose of the Study:

• To examine how animal tissue cells, including BHK cells, neural cell processes, chick heart fibroblasts, and rabbit neutrophils, react to topographical steps.
• To understand the influence of step height and cell type on cell behavior and locomotion.
• To explore the role of adhesive differences and other guidance cues in cellular responses to topography.

Main Methods:

• Utilized photolithographic techniques to fabricate patterned plastic substrata with varying step heights.
• Employed time-lapse videorecording and scanning electron microscopy to observe cell-topography interactions.
• Compared the responses of different cell types (BHK cells, neural cells, fibroblasts, neutrophils) to topographical features.

Main Results:

• BHK cells and neural cell processes showed inhibited crossing and increased alignment with increasing step height.
• Cellular response to topography was cell-type dependent, with neutrophils being less affected by a 5-micron step.
• Adhesive differences altered BHK cell responses, making crossing frequency direction-dependent.
• Topographical features reduced the probability of successful protrusion and contact but were not absolute barriers.

Conclusions:

• Cellular responses to topography are probabilistic and influenced by cell type, step height, and adhesive properties.
• Cytoskeletal inflexibility may play a role, but responses are not deterministic.
• Topographical cues can influence cell locomotion and are important factors in morphogenesis, even when not the primary guidance cue.