Figure 5. Visualization of immunoliposome-binding to total splenocytes. (A) Immunofluorescence of splenocytes stained with a CD4⁺ marker after incubation with immunoliposomes produced with ZZ-GPI_rec and ZZ in a soluble version. CD4+ cells were stained in red, while cells stained by α-CD4 immunoliposome are shown in green; colocalization of both markers is indicated in yellow. Colocalization mainly occurs with ZZ-GPI bound anti-CD4 compared to soluble ZZ. (B) To verify the unspecific DiA staining by α-CD4 immunoliposomes, CD8+ cells were stained with APC. As above, ZZ-GPI-antiCD4 loaded liposomes and soluble ZZ-antiCD4 mixed with liposomes were exposed to cells and no colocalization difference was detected, demonstrating the colocalization background in this test.