Regeneration of sialic acid‐containing components of embryonic cell surfaces

Abstract

Sialic acids such as N-acetylneuraminic acid have been found at the surfaces of various cells. They may play a n important role in intercellular adhesion and hence in animal morphogenesis. This work demonstrates sialic acid at the surfaces of seven-day chick embryo neural retinal cells and its regeneration after enzymatic removal.Neural retinas were excised and dissociated with trypsin. The cells were incubated in a solution of Vibrio cholerae neuraminidase. The enzymatic treatment released sialic acid which was assayed by thg thiobarbituric acid method of Warren. The enzymatic treatment also reduced the cellular electrophoretic mobility from 1.1 to 0.4 X 10 cmlseclvoltlcm measured in 0.067 molar phosphate buffer at pH 7.5.Cells which had been treated with neuraminidase were cultured in a modified Eagle's minimum essential medium for up to 24 hours. During the period of culture, the replacement of surface material was observed i n two ways. First was the progressive return of electrophoretic mobility to the pre-neuraminidase level. Second was the progressive return of sialic acid at the cell surface to the original level. The latter was shown by second neuraminidase treatments and determinations of sialic acid released.Effects of neuraminidase upon the reaggregation of cells cultured on a gyratory shaker in Eagle's medium were investigated. Neuraminidase was not effective for dissociation of neural retina.

A Study on the Mechanism of Intercellular Adhesion

“…In contrast, Kemp (10,11) found that the presence of neuraminidase decreased the aggregation of embryonic chick muscle cells harvested by trypsinization . Measurement of the effect of neuraminidase on the reaggregation of trypsin-dissociated neural retina cells did not yield reproducible results (12) .…”

MCG101‐AA, A NEW ASCITES TUMOUR IN C57 MICE

“…One possible explanation would be that acidic groups regenerated after digestion. Yet, such regeneration should be minimal for cells stored at 0 C, especially since electrophoresis took place immediately upon digestion and washing (Kruemer 1966, Collins et al 1973. We find it more likely that deeply sited negative groups moved into the plane of shear ( Weiss 1969, Singer & Nicolson 1972.…”

Sialic acid and the surface charge associated with hyperpolarization-activated, inward rectifying channels

“…It could be argued that the absence of an effect was due to partial or complete loss of the glycocalyx during the cell isolation procedure (Schanne, Bkaily & Fermini, 1983;Lee & Hsu, 1987). However, sialic acid residues on the cell surface regenerate in culture within 24 hr (Kraemer, 1966;Collins, Holland & Sanchez, 1973;B. Fermini, unpublished results) and can be detected on cardiac myocytes after several days in culture (Frank et al, 1977;Barton, Markwald & Nathan, 1982).…”