Degradation of eschar from venous leg ulcers using a recombinant chymotrypsin from Lucilia sericata.
BACKGROUND
Larvae of the greenbottle Lucilia sericata are used to debride nonhealing wounds and stimulate the production of fresh granulation tissue. Previous publications have shown that secretions from L. sericata contain a number of proteolytic activities including a chymotrypsin that degrades a number of extracellular matrix components such as fibronectin, laminin and collagen.


OBJECTIVE
To produce a recombinant L. sericata chymotrypsin (chymotrypsin I) and determine its effects on the degradation of patient wound eschar.


METHODS
An active recombinant chymotrypsin I from L. sericata was cloned and expressed in Sf9 cells and its subsequent effects ex vivo on eschar from venous leg ulcers were determined by two-dimensional electrophoresis.


RESULTS
The recombinant enzyme had the attributes of a chymotrypsin, possessing sequence homology with other chymotrypsins and demonstrating attributes of the native enzyme including cleavage of the chymotrypsin substrate succinyl-alanyl-alanyl-prolyl-phenylalanyl-7-amino-4-methyl coumarin, inhibition by phenylmethylsulphonyl fluoride and lack of inhibition by amidinophenylmethylsulphonyl fluoride. Importantly, the recombinant chymotrypsin cleaved the majority of proteins from slough/eschar from venous leg ulcers in a superior manner to chymotrypsins from human and bovine sources.


CONCLUSIONS
The ex vivo degradation of eschar from venous leg ulcers indicates the potential value of recombinant chymotrypsin I as a novel, stand-alone debridement agent.
Telford
G
G
Immune Modulation Research Group, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
Brown
A P
AP
Seabra
R A M
RA
Horobin
A J
AJ
Rich
A
A
English
J S C
JS
Pritchard
D I
DI
D000818:Animals; D015153:Blotting, Western; D002417:Cattle; D002918:Chymotrypsin / Q000378:metabolism / Q000494:pharmacology*; D004175:Diptera / Q000201:enzymology*; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007814:Larva / Q000201:enzymology; D040901:Proteomics; D011994:Recombinant Proteins / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D014647:Varicose Ulcer / Q000473:pathology*; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
D011994:Recombinant Proteins; D002918:Chymotrypsin