THE MECHANISM OF ADHESION OF CELLS TO GLASS

An optical technique for measuring the thickness of thin films has been adapted and evaluated for studying the structure of the adhesion of cells to glass in tissue culture. This technique, which is termed interference reflection microscopy, has been used to study embryonic chick heart fibroblasts. These findings have been observed: in normal culture medium the closest approach of the cell surface to substrate in its adhesions is ca. 100 A, much of the cell surface lying farther away; chemical treatments which bring the cell surface to near its charge reversal point reduce the closest approach of adhesions to <50 A, probably to <30 A; chemical treatments which increase surface charge increase the nearest approach of cell and substrate in adhesions from ca. 100 A; high osmotic concentration of a non-polar substance, i.e. sucrose, does not affect the distance between cell and substrate in the adhesions. In addition, optical evidence indicates that there is no extracellular material between cell and glass in the adhesions. When cells de-adhere from glass, they appear not to leave fragments behind. The adhesive sites in these fibroblasts appear to be confined to the edge of the side of the cell facing the substrate and to the pseudopods. The significance of this is discussed in relation to the phenomenon of contact inhibition. Evidence is presented that the mechanism of cell adhesion does not involve calcium atoms binding cells to substrate by combining with carboxyl groups on cell surface, substrate, and with a cement substance. Osmium tetroxide fixation results in a final separation of 100 to 200 A between cell and substrate: there are reasons for thinking that this fairly close approach to the condition in life is produced as an artefact. The results can be accounted for only in terms of the action of electrostatic repulsive forces and an attractive force, probably the van der Waals—London forces. Biological arguments suggest that these results are equally applicable for cell-to-cell adhesions.

[1]  A. Lawrence.  Colloid Science , 1951, Nature.

[2]  M. Rosenberg.  Microexudates from cells grown in tissue culture. , 1960, Biophysical journal.

[3]  A. Curtis.  Cell Contacts: Some Physical Considerations , 1960, The American Naturalist.

[4]  R. Barer,et al.  Chapter 2 – PHASE CONTRAST AND INTERFERENCE MICROSCOPY IN CYTOLOGY , 1956 .

[5]  G. Seaman,et al.  The Surface of the Washed Human Erythrocyte as a Polyanion , 1960, The Journal of general physiology.

[6]  M. Wilkins.  Some aspects of microspectrography , 1950 .

[7]  A. Curtis.  CELL CONTACT AND ADHESION * , 1962, Biological reviews of the Cambridge Philosophical Society.

[8]  M. Abercrombie,et al.  The surface properties of cancer cells: a review. , 1962, Cancer research.

[9]  T. S. Leeson,et al.  EFFECTS OF IN VIVO DECALCIFICATION ON ULTRASTRUCTURE OF ADULT RAT LIVER , 1961, The Journal of biophysical and biochemical cytology.

[10]  L. Weiss.  Cell movement and cell surfaces: A working hypothesis , 1962 .

[11]  E. J. Ambrose,et al.  Surface-contact microscopy. Studies in cell movements. , 1961, Medical & biological illustration.

[12]  H. K. Lewis,et al.  Biological Interactions in Normal and Neoplastic Growth , 1964 .

[13]  D. R. Coman,et al.  Some Chemical Factors in Cellular Adhesion and Stickiness , 1962 .

[14]  J. D. Robertson,et al.  Structural Alterations in Nerve Fibers Produced by Hypotonic and Hypertonic Solutions , 1958, The Journal of biophysical and biochemical cytology.

[15]  B. A. Pethica.  The physical chemistry of cell adhesion. , 1961, Experimental cell research.

[16]  M. Tempel.  Distance between emulsified oil globules upon coalescence , 1958 .

[17]  R. H.,et al.  The Microtomist's Vade-Mecum , 1913, Nature.

[18]  B. Hallert,et al.  A new method for the determination of the distortion and the inner orientation of cameras and projectors , 1954 .

[19]  D. Fawcett.  Observations on the cytology and electron microscopy of hepatic cells. , 1955, Journal of the National Cancer Institute.

[20]  A. Bangham,et al.  On the flocculation of sheep leucocytes: I. Electrophoretic studies , 1962 .

[21]  G. Seaman,et al.  The Influence of pH and Ionic Strength on the Electrokinetic Stability of the Human Erythrocyte Membrane , 1960, The Journal of general physiology.

[22]  M. Abercrombie,et al.  Observations on the social behaviour of cells in tissue culture. II. Monolayering of fibroblasts. , 1954, Experimental cell research.