Surface expression of CD11b in nucleoporated neutrophils. The expression of the human leukocyte integrin subunit CD11b on the surface of nucleoporated neutrophils was analyzed by flow cytometry as described in "Methods." A, Cells were transfected using solution "T" and an electrical current corresponding to program T27. Nucleoporated cells were recovered for 2 h in serum-free RPMI medium (blue lines). Untransfected cells (no pulse) were recovered in RPMI and, where indicated, stimulated with fMLP for 5 min (red lines) or left untreated (green lines). The cells were labeled with anti-CD11b or an isotype-matched control. Expression of CD11b antigen on the surface of treated and untreated neutrophils was analyzed by flow cytometry. The results are representative of three independent experiments. B, Cells were transfected using solution "T" and an electrical current corresponding to program Y01 (blue lines) or not pulsed (green line). The cells were labeled for surface expression of CD11b as described above. The results are representative of three independent experiments. C, Cells were transfected with the expression vector pmaxGFP using the electrical setting corresponding to program Y01. After a 2 h recovery period, the cells were analyzed for the detection of the surface expression of CD11b using a specific antibody conjugated to phycoerythrin (PE, BD Biosciences). The samples were analyzed by flow cytometry as described under "Methods."