Chitotriosidase and gene therapy for fungal infections.
Chitotriosidase secreted by activated human macrophages has been implicated in the defence against chitin-bearing pathogens. The antifungal properties of human chitotriosidase were investigated here following retroviral vector-mediated gene transfer of the open reading frame of the chitotriosidase gene into Chinese hamster ovary cells. A chitinase assay confirmed that the engineered cells secreted recombinant chitotriosidase constitutively. Two dimensional gel electrophoresis and western blotting indicated that the recombinant protein is the major, chitin-binding, fifty kilodalton isoform. Culture medium conditioned by the transduced cells inhibited growth of isolates of Aspergillus niger, Candida albicans and Cryptococcus neoformans. Furthermore, longevity was significantly increased in a mouse model of cryptococcosis when cells transduced with the chitotriosidase gene and encapsulated in alginate microspheres were implanted subcutaneously in the animals. Engraftment of microcapsules containing cells transduced with the chitotriosidase gene has the potential to combat infections caused by chitinous pathogens through the prolonged delivery of recombinant chitotriosidase.
Gordon-Thomson
C
C
School of Natural Sciences, University of Western Sydney, Sydney, Australia. claregt@physiol.usyd.edu.au
Kumari
A
A
Tomkins
L
L
Holford
P
P
Djordjevic
J T
JT
Wright
L C
LC
Sorrell
T C
TC
Moore
G P M
GP
D000464:Alginates; D000818:Animals; D001234:Aspergillus niger / Q000254:growth & development; D016466:CHO Cells / Q000637:transplantation; D002176:Candida albicans / Q000254:growth & development; D006224:Cricetinae; D003412:Cricetulus; D003453:Cryptococcosis / Q000382:microbiology / Q000628:therapy*; D003455:Cryptococcus neoformans / Q000254:growth & development; D017077:Culture Media, Conditioned; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D020723:Glucuronic Acid; D006596:Hexosaminidases / Q000235:genetics / Q000378:metabolism*; D006603:Hexuronic Acids; D006801:Humans; D051379:Mice; D008863:Microspheres; D041681:NIH 3T3 Cells; D011994:Recombinant Proteins / Q000378:metabolism; D012190:Retroviridae / Q000235:genetics
D000464:Alginates; D017077:Culture Media, Conditioned; D006603:Hexuronic Acids; D011994:Recombinant Proteins; D020723:Glucuronic Acid; D006596:Hexosaminidases; C086400:chitotriosidase