Monitoring of Lysosomal Exocytosis

Background of Lysosomal Exocytosis

Unlike the "conventional secretion" mediated by the endoplasmic reticulum-Golgi-secretory vesicle pathway, lysosomal exocytosis is a type of "unconventional secretion", and lysosome can also undergo exocytosis to release their luminal contents. The exocytosis of secretory lysosomes is present in specialized cell types such as hematopoietic cells, whereas the regulated exocytosis of conventional lysosomes is present in all cell types. Upon stimulation, lysosomes translocate to the plasma membrane and fuse, releasing lysosomal contents into the extracellular space. Lysosomal exocytosis represents the major export pathway of lysosomes and plays a key role in a variety of biological processes. In addition, this is also a Ca²⁺-regulated process, and Ca²⁺ ionophores are often used to induce lysosomal exocytosis.

Fig. 1. The molecular machinery and biological functions of lysosomal exocytosis. (Samie M A, et al., 2014)

Our Lysosomal Exocytosis Monitoring Services

Induction of lysosomal exocytosis can effectively reduce lipid accumulation in lysosomal storage disease (LSD), providing a potential therapeutic approach for LSD. For many years, CD BioSciences has been committed to manipulating lysosomal exocytosis to correct the lysosomal and cellular dysfunction caused by excessive lipid storage. Our focus is to clarify the functional interactions between lipid storage and lysosomal cytostasis to analyze the biogenesis of lysosomes. Our engineers have successfully developed several strategies to detect lysosomal exocytosis in vitro.

• Measurement of Lysosomal Hydrolase Activity
  We measured β-hexosaminidase and acid phosphatase activities to reflect the extent of lysosomal exocytosis. This assay can be used to estimate the size of the releasable pool for specific stimuli and conditions in a given time.
• Detection of Lysosomal Membrane Proteins at the Plasma Membrane
  We used a monoclonal antibody against the luminal epitope of the protein to detect LAMP1, a LAMP1 surface staining assay that allows rapid or cumulative detection of lysosomal cytosolic action.
• Detection of Lysosomal Enzymes Released in the Extracellular Environment
  We monitored lysosomal cytokinesis by measuring the release and activity of secreted lysosomal enzymes using appropriate fluorescent or colorimetric substrates.
• Visualization of Lysosomal Exocytosis Action
  We measured lysosomal cytostasis using total internal reflection fluorescence (TIRF) microscopy by establishing cell lines with fluorescent tags designed for lysosomal membrane proteins.
• Electrophysiologically Based Assay of Lysosomal Exocytosis
  We detected the plasma membrane insertion of lysosomal channels during lysosomal cytosol by measuring the whole-cell current of lysosomal ion channels.

Why Choose Us

• A variety of easy-to-implement lysosomal exocytosis assays are available.
• No specific and expensive equipment is required.
• Expertise and well-trained team.
• No require extensive exocytosis, which can be achieved with dozens of cells per sample.
• Lysosomal exocytosis can be distinguished from other forms of exocytosis in conventional and unconventional secretion.
• Lysosomal fusion with the plasma membrane can be observed in living cells.
• Our imaging technology platform enables visualization of the endolysosomal structure of interest at high resolution and also allows assessment of the degree of maturation or dysfunction.

CD BioSciences can meet any reasonable needs of our clients, taking time and budget into consideration for you. Our aim is to be customer-centric and to provide the highest quality services to customers. Our customer service representatives are enthusiastic and trustworthy 24 hours a day, 7 days a week. If you are interested in our services, please feel free to contact us for more information or a detailed discussion.

Reference

1. Samie M A, Xu H. (2014) Lysosomal exocytosis and lipid storage disorders[J]. Journal of lipid research. 55(6): 995-1009.