Leucylleucine methyl ester

Leucylleucine methyl ester is a lysosomotropic dipeptide that is taken up into leukocyte lysosomes via a dipeptide‐specific transport system and cleaved by the granule enzyme dipeptidyl peptidase I (cathepsin C) into hydrophobic oligomers, which disrupt intracellular membranes and selectively kill cytotoxic lymphocytes and other DPPI‐high cells, with species‐dependent sensitivity of B cells (murine B cells sensitive, human B cells largely resistant) .