Immunofluorescence analysis of CLDN5 was performed using 90% confluent log phase HUVEC cells. The cells were fixed with 4% Paraformaldehyde for 10 minutes, permeabilized with 0.1% Triton™ X-100 for 10 minutes, and blocked with 2% BSA for 10 minutes at room temperature. The cells were labeled with Claudin 5 Recombinant Rabbit Monoclonal Antibody (JM11-22) (Product # MA5-32614) at 1:100 dilution in 0.1% BSA, incubated at 4 degree Celsius overnight and then labeled with Goat anti-Rabbit IgG (H+L) Superclonal™ Recombinant Secondary Antibody, Alexa Fluor® 488 conjugate (Product # A27034), (1:2000 dilution) for 45 minutes at room temperature (Panel a: Green). Nuclei (Panel b: Blue) were stained with SlowFade® Gold Antifade Mountant with DAPI (Product # S36938). F-actin (Panel c: Red) was stained with Rhodamine Phalloidin (Product # R415, 1:300). Panel d represents the merged image showing cell membrane localization. Panel e represents HeLa cells with no expression for CLDN5. Panel f represents control cells with no primary antibody to assess background. The images were captured at 60X magnification.