PLA2G15 (also known as LPLA2, Lysosomal Phospholipase A2) is a lysosome-resident phospholipase, requiring critical post-translational modifications (including signal peptide cleavage, N-linked glycosylation, and proteolytic processing) for full enzymatic activation. As a high-risk host cell protein (HCP) in biopharmaceutical manufacturing, particularly from Chinese Hamster Ovary (CHO) cells, it is routinely monitored due to its high immunogenic potential, and its tendency to persist through downstream purification processes due to low clearance efficiency.