The effect of bovine lactoferrin and lactoferricin B on the ability of feline calicivirus (a norovirus surrogate) and poliovirus to infect cell cultures.
OBJECTIVE
To characterize the effect of bovine lactoferrin and lactoferricin B against feline calicivirus (FCV), a norovirus surrogate and poliovirus (PV), as models for enteric viruses.


RESULTS
Crandell-Reese feline kidney (CRFK) cells were used for the propagation of FCV and monkey embryo kidney (MEK) cells for PV. The assays included visual assessment of cell lines for cytopathic effects and determination of the percentage cell death using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium] dye reduction assay. Incubation of bovine lactoferrin with CRFK cells either prior to or together with FCV inoculation substantially reduced FCV infection. In contrast, the interference of lactoferrin with the infection of cells with PV was demonstrated only when lactoferrin was present with cell lines and virus for the entire assay period. Using indirect immunofluorescence, lactoferrin was detected on the surface of both CRFK and MEK cells, suggesting that the interference of viral infection may be attributed to lactoferrin binding to the surfaces of susceptible cells, thereby preventing the attachment of the virus particles. Lactoferricin B, a cationic antimicrobial peptide derived from the N-terminal domain of bovine lactoferrin, reduced FCV but not PV infection.


CONCLUSIONS
Lactoferrin was shown to interfere with the infection of cells for both FCV and PV. However, lactoferricin B showed no interference of infection with PV and interference with infection for FCV required the presence of lactoferricin B together with the cell line and virus.


CONCLUSIONS
An in vitro basis is provided for the effects of bovine lactoferrin and lactoferricin B in moderating food-borne infections of enteric viruses.
McCann
K B
KB
Institute of Land and Food Resources, The University of Melbourne, Werribee, Victoria, Australia.
Lee
A
A
Wan
J
J
Roginski
H
H
Coventry
M J
MJ
D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D017250:Caliciviridae Infections / Q000517:prevention & control; D017927:Calicivirus, Feline / Q000187:drug effects* / Q000472:pathogenicity; D002415:Cats; D002417:Cattle; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D000882:Haplorhini; D007781:Lactoferrin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D011051:Poliomyelitis / Q000517:prevention & control; D017955:Poliovirus / Q000187:drug effects* / Q000472:pathogenicity; D014774:Virulence / Q000187:drug effects
D000998:Antiviral Agents; C082171:lactoferricin B; D007781:Lactoferrin