Once brought into the cell, the receptor-proenzyme complex vesicle is transported to the lysosome where the lower pH promotes both dissociation of the proenzyme from the receptor and activation of the proenzyme to its active catalytic form via cleavage of the proenzyme sequence.Like natural TPP1, cerliponase alfa functions as a serine protease, cleaving N-terminal tripeptides from a broad range of protein substrates. The enzyme uses a catalytic triad active site composed of the three amino acids, aspartic acid, glutamic acid, and serine. Serine functions as the amino acid that performs the nucleophilic attack during the ping pong catalytic activity of a serine protease. The products of this reaction are a tripeptide and the remaining length of the protein substrate with a new N-terminal end that can be cleaved again. In CLN2 disease, TPP1 is deficient or not made at all, meaning that proteins are unable to be degraded in the lysosome and accumulate, leading to damage in nerves. As a protein, cerliponase alfa gets degraded by proteolysis. Therefore, cerliponase alfa is administered repeatedly to maintain sufficient levels of the recombinant TPP1 enzyme in place of the deficient form to degrade proteins and prevent further build up. Cerliponase alfa is a treatment that can potentially slow disease progression but does not cure the disease itself. References
External links
"Cerliponase alfa". Drug Information Portal. U.S. National Library of Medicine.
HPC is also used as a lubricant for artificial eyes. HPC is used as a thickener, a low level binder and as an emulsion stabiliser with E number E463. In pharmaceuticals it is used as a binder in tablets. HPC is used as a sieving matrix for DNA separations by capillary and microchip electrophoresis.HPC is the main ingredient in Cellugel, which is used in book conservation. Cellugel is described as "A safe, penetrating consolidant for leather book covers affected by red rot" and is produced by Preservation Solutions. See also
Carboxymethyl cellulose
Methyl cellulose
Hypromellose


== Notes and references ==