Appearance of isochromosome 18q can be associated with in vitro immortalization of human T lymphocytes

T lymphocytes cultured from a skin biopsy specimen of a patient with atopic dermatitis developed isochromosome 18q concomitant to escape from replicative senescence. Furthermore, two T -cell lines established from patients with cutaneous Tcell lymphoma also developed isochromosome 18q during continuous growth. The results indicate that a pathway leading to immortalization of human T lymphocytes could involve genes located at chromosome 18.