Search

Background: Zika virus (ZIKV) infection gained public health concern after the 2015 outbreak in Brazil, when microcephaly rates increased in babies born from infected mothers. It was demonstrated that ZIKV causes a congenital Zika virus syndrome, including various alterations in the development of the central nervous system. Although the infection of cells from the nervous system has been well documented, less is known in respect of ZIKV ability to infect immune cells. Herein, we investigated if peripheral blood mononuclear cells (PBMCs), freshly-isolated from healthy donors, could be infected by ZIKV.Methods: PBMCs from healthy donors were isolated and cultured in medium with ZIKV strain Rio-U1 (MOI = 0.1). Infection was analyzed by RT-qPCR and flow cytometry.Results: We detected the ZIKV RNA in PBMCs from all donors by RT-qPCR analysis. The detection of viral antigens by flow cytometry revealed that PBMC from more than 50% the donors were infected by ZIKV, with CD3+CD4+ T cells, CD3-CD19+ B cells and CD3+CD8+ T cells being, respectively, the most frequently infected subpopulations, followed by CD14+ monocytes. Additionally, we observed high variability in PBMC infection rates among different donors, either by numbers or type infected cells.Conclusions: These findings raise the hypothesis that PBMCs can act as a reservoir of the virus, which may facilitate viral dissemination to different organs, including immune-privileged sites. [ABSTRACT FROM AUTHOR]

Background: Primary cutaneous CD30+ lymphoproliferative disorders (pc-CD30-LPD) are a group of clonal T cell lymphoproliferative disorders that despite very similar tumor histology follow different and characteristic clinical courses, suggesting a homeostatic role of the tumor microenvironment. Little is known about tumor microenvironment and there is almost no literature about PD-L1 expression in pc-CD30-LPD. Methods: This retrospective study presents a fully clinicopathologically characterized series of pc-CD30-LPDs from an academic medical center in Brazil, including 8 lymphomatoid papulomatosis (LyP), 9 primary cutaneous anaplastic large cell lymphoma (pcALCL) and 4 borderline lesions. All the cases were scored for FOXP3+ regulatory T-cells (Treg) and CD8+ cytotoxic tumor infiltrating lymphocytes (TIL) densities, as well as PD-L1 expression in tumor cells and tissue associated macrophages. The CD8+/FOXP3+ ratio was also evaluated. Results: Among the 21 cases of pc-CD30-LPD, PD-L1 expression is frequent in both tumor cells and tissue associated macrophages in pc-CD30-LPD across categories, suggesting that the PD-L1 axis may be a common feature of pc-CD30-LPDs. While reactive T cell infiltrates vary widely from case to case, a common feature across pc-CD30-LPDs is higher density of CD8 than FOXP3 + T cells. The distribution of T cells within the lesions however differed between LyP and pcALCL: we found that LyP lesions tend to be permeated by CD8+ and FOXP3+ T cells, whereas pcALCL tend to be surrounded by a rim of CD8+ TIL and FOXP3+ Tregs with relatively lower density infiltrates in the center of the lesion. Conclusions: LyP has a trend to have denser immune cells throughout the lesion, with higher FOXP3+ Treg and CD8+ TIL in the center than the edge comparing with pcALCL. PD-L1+ is frequent in tumor cells and tissue associated macrophages in pc-CD30-LPD. The differential distribution of CD8+ and FOXP3+ TILs in LyP as compared to pcALCL could provide a clue to the relapsing/remitting course of LyP as compared to the less frequent spontaneous regression of pcALCL. [ABSTRACT FROM AUTHOR]