title: Immobilized IL-2 preserves the viability of an IL-2 dependent cell line.
abstract: The mouse T-cell line CTLL-2 is known to be dependent on interleukin-2 (IL-2) for both growth and viability. These cells possess high affinity IL-2 receptors and have been shown to internalize IL-2 after binding. To determine if internalization of IL-2 is required for the mediation of its signal, IL-2 was covalently coupled to an insoluble matrix via glutaraldehyde cross-linking and CTLL-2 cells were incubated with the immobilized lymphokine matrix. This covalent cross-linking prevents the free lateral diffusion and internalization of the bound IL-2 receptors (IL-2R) while still permitting specific binding between the cells and the immobilized ligands. Although only very limited proliferation was observed during the incubation as assessed by 3H-thymidine incorporation, the viability of the CTLL-2 cells on the immobilized IL-2 matrix was preserved. Cells incubated on the immobilized IL-2 surface could proliferate in response to exogenous soluble IL-2 that was added to the cultures after 36 hours whereas control cultures incubated with an immobilized BSA matrix had died. This indicates that immobilized IL-2 can mediate some of the activity of soluble IL-2 and that internalization of the IL-2 receptor may not be required for at least part of the IL-2 mediated effect.
authors.affiliation: Surgical Services, Massachusetts General Hospital, Boston 02114.
authors.forename: J I
authors.initials: JI
authors.lastname: Horwitz
authors.forename: M
authors.initials: M
authors.lastname: Toner
authors.forename: R G
authors.initials: RG
authors.lastname: Tompkins
authors.forename: M L
authors.initials: ML
authors.lastname: Yarmush
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects*; D007376:Interleukin-2 / Q000032:analysis / Q000494:pharmacology*; D051379:Mice; D013601:T-Lymphocytes / Q000166:cytology* / Q000187:drug effects
chemical_list: D007376:Interleukin-2