Infection of Human Retinal Pigment Epithelial Cells with Dengue Virus Strains Isolated during Outbreaks in Singapore

Abstract

Prevalence of dengue retinopathy varies across epidemics, with the disease linked to circulation of dengue virus serotype 1 (DENV-1). The retinal pigment epithelium has been implicated in the pathology. We investigated infectivity, molecular response, and barrier function of epithelial cells inoculated with DENV strains from different outbreaks in Singapore. Monolayers of human retinal pigment epithelial cells (multiple primary cell isolates and the ARPE-19 cell line) were inoculated with six DENV strains, at multiplicity of infection of 10; uninfected and recombinant strain-infected controls were included where relevant. Infectivity and cell response were assessed primarily by RT-qPCR on total cellular RNA, and barrier function was evaluated as electrical resistance across monolayers. Higher viral RNA loads were measured in human retinal pigment epithelial cells infected with DENV-1 strains from the 2005 Singapore epidemic, when retinopathy was prevalent, versus DENV-1 strains from the 2007 Singapore epidemic, when retinopathy was not observed. Type I interferon (IFN) transcripts (IFN-β and multiple IFN-stimulated genes) were up-regulated, and impact on barrier function was more pronounced, for cells infected with DENV-1 strains from the 2005 versus the 2007 Singapore epidemics. Aside from serotype, strain of DENV may determine the potential to induce retinal pathology. Identification of molecular markers of disease-associated DENV strains may provide insights into the pathogenesis of dengue retinopathy.

Vav proteins do not influence dengue virus replication but are associated with induction of phospho-ERK, IL-6, and viperin mRNA following DENV infection in vitro

“…Additionally, on-line data from the human protein atlas ( https://www.proteinatlas.org/ ) predict THP-1 to express Vav1, −2, and −3, which complicate a reductionist approach to study the different Vav proteins individually. ARPE-19 cells are derived from the retinal pigmented epithelium, and were chosen to assess the links between Vav and DENV-responses further, not as a model of macrophages, but as a reproducible cell line that are highly susceptible to DENV-infection with the majority of cells in the population infected, have a normal role in inflammatory responses in the eye and reflect a cell type that has relevance to DENV disease ( 42 , 43 , 44 ). Cells were infected and, at 48 hpi, fixed or RNA extracted.…”

Subconfluent ARPE-19 Cells Display Mesenchymal Cell-State Characteristics and Behave Like Fibroblasts, Rather than Epithelial Cells, in Experimental HCMV Infection Studies

“…Ebola) [126], flaviviruses (e.g. Zika or Dengue) [127][128][129], and coronaviruses (e.g. SARS-CoV-2) [130].…”

Subconfluent ARPE-19 Cells Display Mesenchymal Cell-State Characteristics and Behave like Fibroblasts, Rather Than Epithelial Cells, in Experimental HCMV Infection Studies

“…ARPE-19 cells are a commonly used epithelial infection model for HCMV [ 17 , 18 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 ], as well as other human herpesviruses (e.g., VZV or HSV-1) [ 123 , 124 , 125 ], filoviruses (e.g., Ebola) [ 126 ], flaviviruses (e.g., Zika or Dengue) [ 127 , 128 , 129 ], and coronaviruses (e.g., SARS-CoV-2) [ 130 ]. Despite a number of studies showing that ARPE-19 requires prolonged periods of contact inhibited cell culture for functional differentiation [ 9 , 24 ], the use of undifferentiated, low-confluency ARPE-19 cultures (95% to just confluent) for infection studies is common.…”