Infection profiles of Mayaro virus and Chikungunya virus in mammalian and mosquito cell lineages

OBJECTIVE: To trace the infection profile of Mayaro virus (MAYV) and Chikungunya virus (CHIKV) in four different cell lineages. MATERIALS AND METHODS: The isolates of these viruses were used to infect cultures of the following cell lineages - C6/36, VERO, BHK-21, and LLC-MK2 - under the multiplicity of infection of 1 PFU/cell, which were monitored for up to 96 h post-infection (hpi) by phase-contrast microscopy to register the cytopathic effect (CPE); and in addition were subjected to indirect immunofluorescence (iIF) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays for virus antigen detection and RNA load determination, respectively. RESULTS: For both viruses, VERO and BHK-21 cells had CPE of 24 hpi, LLC-MK2 cells presented CPE from 48 hpi, and C6/36 did not present any CPE. In the iIF assays, all cells were already positive at 6 hpi, with the exception of CHIKV-infected LLC-MK2 and BHK-21 cells. Finally, qRT-PCR assays showed that in general cells infected with MAYV presented higher RNA load, although CHIKV-infected LLC-MK2 cells showed the highest RNA load. CONCLUSION: By evaluating the behavior of these arboviruses in different types of cell cultures, including some not commonly used in the laboratory diagnostic routine, the present study provides not only a better comprehension of the replication kinetics of MAYV and CHIKV, but also opportunities for the optimization of their diagnosis in biological samples.