CTSK and achalasia-alacrima syndrome: In a subsequent study, doxycycline loaded into cationic amphiphile modified submicron particles were surface modified with a specific antibody, which acts upon the lysosomal protease, cathepsin K. Since cathepsin K tend to overexpressed during the growth and progression of AAAs, the spatially designed platforms not only controlled the sustained release of doxycycline but also specifically act upon the cathepsin K and thus controls the regulation of its expression profile.