In lysosomes

A (Hex A) catalyzing the biodegradation of gangliosides. Accumulation of gangliosides in lysosomes primarily affects brain neurons. In the early onset form of the disease, children become blind, deaf, and unable to swallow. Children die usually before the age of three. A late onset form ofthe disease occurs in young adults and is usually nonfatal. 

S, Reis e Sousa C, Germain RN, Mellman I, Steinman 48 RM The formation of immunogenic major histocompatibility complex class Il-peptide ligands in lysosomal compartments of dendritic cells is regulated by inflammatory stimuli. J Exp Med 2000 191 927-936. 49... 

As shown in Table I, free HRP is poorly transported across MDCK cells but, when conjugated to a PLL carrier, HRP transport is increased considerably. The existence of a proteolytic compartment involved in the transcytotic digestion of HRP-S-PLL conjugate was further confirmed by the finding that when PLL was replaced by PDL, the transport of HRP was completely abolished (Table I) (8). In addition, when protease inhibitors such as leupeptin were added to the basal medium, the transcytosis of HRP was also significantly decreased (Table I). We have previously reported that the partial degradation of HRP-S-PLL was not inhibited by lysosomotropic amines (<8), indicating that this proteolytic process does not occur in lysosomes. 

Several dendrimeric borane and carborane systems have been developed for use as boron-delivery agents.147 In vitro tests with a boronated dendrimer-epidermal growth factor bioconjugates indicated that they are endocytosed, resulting in the accumulation of boron in lysosomes. 

Hydrolysis of triacylglycerides in tissues is effected by a tissue enzyme, tri-acylglyceride lipase, which hydrolyzes triacylglycerides to glycerol and free fatty acids. There are a variety of tissue lipases that differ primarily in their optimum pH and their location in the cell. The acidic lipase is contained in lysosomes the basic lipase, in microsomes and the neutral lipase, in cytoplasm. A specific feature of the tissue lipase is its sensitivity to hormones which, by activating adenylate cyclase, elicit the transition of the inactive tissue lipase to its active... 

Munier-Lehmann, H., Mauxion, F. and Hoflack, B. Function of the two mannose 6-phosphate receptors in lysosomal enzyme transport. Biochem. Soc. Trans. 24 133-136,1996. 

Defect in lysosomal enzyme protection Defects in soluble non-enzymatic lysosomal proteins... 

Glycoproteins derivatized with DTPA at surface lysine residues and labelled with Gd(III) (or In(III)) are internalized by cells and metabolized to Gd(-DTPA-lysine), which is released only slowly from cells (323). Some Gd(III) may dissociate from this complex since the pH in lysosomes, where the metabolism occurs, is low (pH 5). 

Ludwig, T., Le Borgne, R., and Hoflack, B. (1995). Roles for mannose-6-phosphate receptors in lysosomal enzyme sorting, IGF-II binding and clathrin-coat assembly. 

PS that localize in lysosomes tend to produce apoptosis more slowly after illumination than mitochondrial PS, due to the release of lysosomal enzymes that subsequently activate cytoplasmic caspases (Kessel et al., 2000). 

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