From Biology-Online Dictionary | Biology-Online Dictionary

Immortalization --> immortalisation

(Science: cell biology) The ability of a genetically engineered cell line to reproduce indefinitely

The cells escape from the normal limitation on growth of a finite number of division cycles (the Hayflick limit), by variants in animal cell cultures and cells in some tumours.

Immortalisation in culture may be spontaneous, as happens particularly readily in mouse cells or induced by mutagens or by transfection of certain oncogenes.