T-cell-fibroblast hybridoma deformability and concanavalin A-induced agglutination

Cell adhesion influences many important immunological functions such as phagocytosis or T-cell-mediated cytotoxicity. Previous work suggested that the ease of inducing intercellular bonds (i.e. binding efficiency) and the difficulty to separate bound cells with mechanical forces (i.e. binding strength) might be parameters of different significances. The present report describes a study made on two T-lymphocyte/polyoma virus transformed fibroblast hybrid subclones (3D1c and 3D1n) with markedly different adhesive properties: indeed, 3D1c cells were at the same time more readily agglutinated with concanavalin A and more easily disagglutinated than 3D1n. In order to understand these differences, a systematic comparison of various properties of 3D1c and 3D1n cells was undertaken. The following parameters were studied: surface density of concanavalin A binding sites, surface electrostatic charge, hydrophobicity, fluorescence polarization measured on individual cells, and ability to spread on a flat substrate in response to volume or surface forces. It is concluded that cell deformability and/or spreading ability might be an important determinant of binding strength, but the factors governing binding efficiency remained incompletely understood. It is suggested that the methods described in the present report might help understanding differences between various tumor cell lines with different malignant potential.