Application of quantitative immunofluorescence assays to analyze the expression of cell contact proteins during Zika virus infections

LEIVA SANTIAGO1, DIZANZO MARÍA PAULA1, FABBRI CINTIA2, BUGNON VALDANO MARINA1, LUPPO MARÍA VICTORIA2, LEVIS SILVANA2, CAVATORTA ANA LAURA1, MORALES MARÍA ALEJANDRA2 AND GARDIOL DANIELA

Congreso; LVI Reunión Anual de SAIB?-; 2020

SAIB-SAMIGE

Zika Virus (ZIKV) is an RNA virus that belongs to the Flavivirus (FV) genus. In the last years, several unique characteristics of ZIKV among the FV have been revealed, as the multiple routes of transmission and its ability to reach different human tissues, including the central nervous system. Thus, one of the most intriguing features of ZIKV biology is its ability to cross several complex biological barriers. The main aim of this study is to contribute to the understanding of the still unclear mechanisms behind this viral activity. We investigated an African strain and two South American ZIKV isolates belonging to the Asian lineage, in order to characterize possible differences regarding their ability to disturb intercellular junctions. The Asian isolates correspond to an imported and an autochthonous ZIKV strain previously isolated in Argentina and for which there is still no data available. We focused on occludin and DLG1 expression as markers of tight and adherent junctions, respectively. For this, we applied a robust quantitative immunofluorescence assay that can accurately ascertain alterations in the cell junction proteins expression in the infected cells. Our findings indicated that the different studied ZIKV strains were able to reduce the levels of both analyzed polarity proteins without altering their overall cell distribution. Moreover, the grade of this effect was strain-dependent and was neither related to the viral replication nor the infection capacity. Interestingly, among both junction proteins analyzed the viral infection caused a relative higher reduction in DLG1 expression, suggesting it is of particular relevance for ZIKV infections. Taken together, this study contributes to the knowledge of the biological mechanisms involved in ZIKV cytopathogenesis, with a special focus on regional isolates.