Cellular blebs: pressure-driven, axisymmetric, membrane protrusions
- 753 Downloads
Blebs are cellular protrusions that are used by cells for multiple purposes including locomotion. A mechanical model for the problem of pressure-driven blebs based on force and moment balances of an axisymmetric shell model is proposed. The formation of a bleb is initiated by weakening the shell over a small region, and the deformation of the cellular membrane from the cortex is obtained during inflation. However, simply weakening the shell leads to an area increase of more than 4 %, which is physically unrealistic. Thus, the model is extended to include a reconfiguration process that allows large blebs to form with small increases in area. It is observed that both geometric and biomechanical constraints are important in this process. In particular, it is shown that although blebs are driven by a pressure difference across the cellular membrane, it is not the limiting factor in determining bleb size.
KeywordsBleb Shell model Force balance Membrane growth Cell mechanics
This publication is based on work supported by Award No. KUK-C1-013-04, made by King Abdullah University of Science and Technology (KAUST). AG is a Wolfson Royal Society Merit Holder and acknowledges support from a Reintegration Grant under EC Framework VII.
- Evans EA, Skalak R (1980) Mechanics and thermodynamics of biomembranes. CRC Press, Boca Raton, FLGoogle Scholar
- Hu J (2009) Mathematical modeling and analysis of in vitro Actin filament dynamics and cell blebbing. PhD thesis, University of MinnesotaGoogle Scholar
- Keller H, Eggli P (1998) Protrusive activity, cytoplasmic compartmentalization, and restriction rings in locomoting blebbing Walker carcinosarcoma cells are related to detachment of cortical actin from the plasma membrane. Cell Motil Cytoskelet 41(2):181–193 Google Scholar
- Lim FY, Chiam KH, Mahadevan L (2012) The size, shape, and dynamics of cellular blebs. Bull Am Phys Soc 55:1–6Google Scholar
- Nichol JA, Hutter OF (1996) Tensile strength and dilatational elasticity of giant sarcolemmal vesicles shed from rabbit muscle. J Phys 493:187Google Scholar
- Russell SW, Rosenau W, Lee JC (1972) Cytolysis induced by human lymphotoxin: cinemicrographic and electron microscopic observations. Am J Pathol 69(1):103Google Scholar
- Strychalski W, Guy RD (2012) A computational model of bleb formation. Math Med Biol 30:115–130Google Scholar