Distinct migratory pattern of naive and effector T cells through the blood–CSF barrier following Echovirus 30 infection

Abstract

Background: Echovirus 30 (E-30) is one of the most frequently isolated pathogens in aseptic meningitis worldwide. To gain access to the central nervous system (CNS), E-30 and immune cells have to cross one of the two main barriers of the CNS, the epithelial blood-cerebrospinal fluid barrier (BCSFB) or the endothelial blood-brain barrier (BBB). In an in vitro model of the BCSFB, it has been shown that E-30 can infect human immortalized brain choroid plexus papilloma (HIBCPP) cells. Methods: In this study we investigated the migration of different T cell subpopulations, naive and effector T cells, through HIBCPP cells during E-30 infection. Effects of E-30 infection and the migration process were evaluated via immunofluorescence and flow cytometry analysis, as well as transepithelial resistance and dextran flux measurement. Results: Th1 effector cells and enterovirus-specific effector T cells migrated through HIBCPP cells more efficiently than naive CD4 + T cells following E-30 infection of HIBCPP cells. Among the different naive T cell populations, CD8 + T cells crossed the E-30-infected HIBCPP cell layer in a significantly higher number than CD4 + T cells. A large amount of effector T cells also remained attached to the basolateral side of the HIBCPP cells compared with naive T cells. Analysis of HIBCPP barrier function showed significant alteration after E-30 infection and trans-as well as paracellular migration of T cells independent of the respective subpopulation. Morphologic analysis of migrating T cells revealed that a polarized phenotype was induced by the chemokine CXCL12, but reversed to a round phenotype after E-30 infection. Further characterization of migrating Th1 effector cells revealed a downregulation of surface adhesion proteins such as LFA-1 PSGL-1, CD44, and CD49d. Conclusion: Taken together these results suggest that naive CD8 + and Th1 effector cells are highly efficient to migrate through the BCSFB in an inflammatory environment. The T cell phenotype is modified during the migration process through HIBCPP cells.

Human CD4+ T cell subsets differ in their abilities to cross endothelial and epithelial brain barriers in vitro

“…Preliminary observations made with the Th cell subsets used in the present study confirm involvement of GPCR signaling in the diapedesis of all Th subsets across BLEC monolayers. Furthermore, our previous studies have shown that addition of exogenous CXCL12 to the CSF side increased T-cell migration across HIBCPP monolayers [31,68,69]. These data support the additional role for GPCR signaling in the migration of effector Th cell subsets across the BBB and BCSFB.…”

“…Both BLECs and HIBCPP cells have previously been shown to phenocopy characteristics of a functional BBB and BCSFB, respectively. BLECs and HIBCPP form mature adherens and tight junctions, show low permeability to small molecular tracers, establish high electrical resistance, show functional expression of characteristic transporters and efflux pumps and display apical/basolateral polarity [22][23][24][25][26][27][28][29][30][31]. In addition, both human brain barrier models were previously shown by us and others to show cytokine inducible expression of adhesion molecules and to be suitable for studying immune cell trafficking across the BBB and BCSFB in vitro [26,28,[32][33][34].…”

Localization of ZIP14 and ZIP8 in HIBCPP Cells

“…A reliable in vitro model that uses an immortalized and widely available cell line would help to standardize the experiments and results surrounding BCB research. HIBCPP cells have recently been identified as a consistent model of the BCB, and several publications have utilized these cells as a barrier model [ 5 , 6 , 7 ]. The HIBCPP cell line was established in 2005 from a human choroid plexus papilloma [ 8 ] and has been characterized in several studies that indicate that HIBCPP cells have many critical functional characteristics of choroid plexus epithelial cells—namely, the ability to polarize and express marker proteins to match choroid plexus epithelial cells in vivo [ 5 , 6 , 9 ].…”

Polar Infection of Echovirus-30 Causes Differential Barrier Affection and Gene Regulation at the Blood–Cerebrospinal Fluid Barrier

“…Among the enteroviruses, Echovirus-30 (E-30) is a nonpolio enterovirus (NPEV) species B, responsible for extensive global outbreaks of meningitis in children [ 8 , 9 , 10 ], and which can result in mild symptoms, but might also rapidly evolve towards a lethal outcome [ 11 , 12 ]. Several clinical studies revealed that enterovirus infection of the CNS results in increased levels of inflammatory chemokines within the cerebrospinal fluid (CSF), including INF-γ , CXCL12 , CXCL10 , IL-6 , IL-1 and TNF-α , which increase the influx of neutrophils and T cells into the brain parenchyma [ 13 , 14 , 15 ]. However, the underlying mechanisms used by these viruses to enter the brain and induce CNS inflammation are not fully understood yet.…”