Controlled release of anti-inflammatory peptides from reducible thermosensitive nanoparticles suppresses cartilage inflammation

The anti-inflammatory MK2 inhibiting peptide, KAFAKLAARLYRKALARQLGVAA (KAFAK), has shown promise as a therapy for osteoarthritis; however its susceptibility to proteases in the blood and synovial fluid limits its therapeutic potential. Here we investigate a thermosensitive nanoparticle system to protect KAFAK from premature extracellular degradation. The nanoparticles are stable in the extracellular environment, but degrade upon uptake into cells through reduction of disulfide crosslinks. This study shows that these nanoparticles are taken up into chondrocytes, delivering KAFAK and suppressing inflammation to a greater extent than non-degradable nanoparticle counterparts.271