Résumé
The inhibitory activity of caffeine, a pharmacologically active compound, on Junin virus (JV) multiplication in Vero cells was evaluated by a virus yield inhibition assay. The compound achieved a dose-dependent inhibition of virus production at concentrations not affecting cell viability. The 50 inhibitory concentration (IC50) and the 90 inhibitory concentration (IC90) were 9.0 mM and 10.8 mM, respectively. From time of addition experiments, it can be concluded that caffeine inhibited an early stage in the replicative cycle of JV occuring before 4 h of infection. Extracellular and cell-associated virus yields were reduced to the same extent. The addition of caffeine after several cycles of infection for a very short treatment period did not significantly affect the formation of JV infectious particles. The expression of viral proteins in the cytoplasm and the membrane of infected cells was highly reduced in the presence of caffeine, as revealed by immunofluorescence staining, confirming that caffeine predominantly exerted its inhibitory action early in the infection of Vero cells with JV.
Sujets)
Animaux , Antiviraux , Caféine/pharmacologie , Virus Junin , Réplication virale/effets des médicaments et des substances chimiques , Antiviraux , Caféine/administration et posologie , Chlorocebus aethiops , Relation dose-effet des médicaments , Technique d'immunofluorescence indirecte , Protéines virales/biosynthèse , Facteurs temps , Cellules VeroRésumé
Se investigó la naturaleza bioquímica de las estructuras presentes en la superficie de células Vero, implicadas en la interacción con el virus Junín (cepa XJ C13) y una mutante de rango de huésped denominada Cl 67. Los tratamientos enzimáticos realizados a las células antes de la infección indican que las primeras moléculas que interaccionan con el virus Junín serían proteínas o grupos proteícos con aminoácidos básicos o aromáticos expuestos, existiendo diferencias en la afinidad hacia las cepas estudiadas