Detection of influenza C virus by using an in situ esterase assay.
A variety of chemically defined compounds were tested to characterize the substrate specificity of the influenza C virus esterase and to determine whether a substrate could be found that would be useful in an assay to detect the virus. Two new substrates, alpha-naphthyl acetate and alpha-naphthyl propionate, were identified; alpha-naphthyl acetate was employed to develop an assay specific for influenza type C virus in MDCK cells. The assay was sufficiently sensitive to detect esterase activity in a single cell and distinguished influenza C virus infections from those of types A and B viruses. Infected cells could be detected as early as 8 h postinfection, with maximal enzyme detection occurring at 24 h. Assay of influenza C virus in the chorioallantoic or amniotic fluid of infected eggs was performed by applying fluids directly onto nitrocellulose strips and then incubating with alpha-naphthyl acetate. Both the cellular and nitrocellulose-bound assays are rapid, inexpensive, and easy to perform, offering advantages for use in clinical laboratories.
Wagaman
P C
PC
Department of Microbiology, Immunology, and Parasitology, School of Medicine, Louisiana State University Medical Center, New Orleans 70112.
Spence
H A
HA
O'Callaghan
R J
RJ
D000818:Animals; D002642:Chick Embryo; D004950:Esterases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009982:Gammainfluenzavirus / Q000201:enzymology / Q000302:isolation & purification*; D009281:Naphthalenes / Q000378:metabolism*; D009284:Naphthols / Q000378:metabolism; D009596:Nitrophenols / Q000378:metabolism; D009975:Orthomyxoviridae / Q000302:isolation & purification*; D011422:Propionates / Q000378:metabolism*; D013379:Substrate Specificity; D013696:Temperature
D009281:Naphthalenes; D009284:Naphthols; D009596:Nitrophenols; D011422:Propionates; C060294:1-naphthalenepropionic acid; C008642:4-nitrophenyl acetate; C027876:alpha-naphthyl acetate; D004950:Esterases