Figure 11.

In-vivo study of DK17 permeability to blood-brain barrier (BBB) and blood-spinal cord barrier (BSB) in mice models. Wild type (WT) and mutated DK17 peptides were conjugated with Alexa Fluor 680 (AF680) infrared dye followed by treatment of control female SJL/J mice (5-6 week old) with AF680-conjugated WT and mutated DK17 peptides (200 ng/mouse) via tail-vein injection. After 3 h, mice were scanned in an Odyssey (ODY-0854; Licor) infrared scanner at the 700- and 800-nm channels (A). Mice were perfused with 4% paraformaldehyde. Spinal cord (B) and different parts of the brain (C) were scanned in an Odyssey infrared scanner. The red background comes from 800-nm filter, whereas the green signal is from AF680 at the 700-nm channel. Wild type DK17 is able to translocate through BSB and BBB, therefore it displays signal both in different sections of brain and spinal cord. However, the translocation of mut-DK17 seems to be restricted in the tail region only indicating its impermeability to CNS. The density of the AF680 signal in different parts of the brain (D) was quantified. Data (relative to AF680 control) are expressed as the mean ± SEM of five different mice (n=5) per group. ^ap<0.001 vs AF680.