PLBD2

PLBL2 (also annotated as PLBD2, phospholipase B–like 2) is a lysosome-localized, functionally semi-orphan member of the phospholipase B family. Its mature, active form depends on ordered post-translational processing—signal-peptide removal, mannose-6-phosphate–mediated lysosomal targeting, and an autocatalytic cleavage step. In biopharmaceutical production, especially from CHO cells, PLBL2 is classified among high-risk host cell proteins (HCPs): it persists through downstream purification owing to its stability and clearance-resistant properties, creating a potential immunogenicity hazard (anti-HCP/anti-drug antibody risk) that mandates sensitive, specific monitoring.