Hsp47. The Heat Shock Protein 47 targets collagen folding and function. Hsp47 excess caused tissue fibrosis and/or cancer. The Hsp47 main binding site include some molecular species of collagen . Although some Hsp47 inhibitors (i.e., Hs55) supressed excesive collagen synthesis in in vitro models 61 they were only active at µM affinities. No Hsp47 have been targeted by DW-BEL.