Figure 2

Subcellular localization of EYFP-IκBα and EYFP-p65 fusion proteins in CD ₄ ⁺ T lymphocytes. (a) Cells were transiently transfected with 1 μg of either EYFP-IκBα or EYFP-p65 expression vectors per million of cells. LMB was added immediately after transfection. After 18–24 hours of incubation, cells were analyzed by confocal microscopy. pEYFP-C1 vector was used as control of unspecific distribution. (b) Resting purified CD₄⁺ T lymphocytes were transiently transfected with the control plasmid pcDNA3.1 by using an Amaxa nucleofector and a classical electroporator (Equibio). As occurs in untransfected resting T cells (lane 1), NF-κB was not induced in resting CD₄⁺ T lymphocytes after electroporation (lanes 3 and 4). As a positive control, NF-κB (p50/p65) binding was induced in these cells by PMA activation (lane 2).