Epidemiological studies found that hepatitis E virus genotype 3 (HEV-3) infection was associated with chronic hepatitis and cirrhosis in immunocompromised patients. Our study aimed to investigate the relationship between the host immunosuppressive status and the occurrence of HEV-related chronic hepatitis. Here we describe a successful experimental study, using cynomolgus monkeys previously treated with tacrolimus, a potent calcineurin inhibitor immunosuppressant, and infected with a Brazilian HEV-3 strain isolated from naturally infected pigs. HEV infected monkeys were followed up during 160 days post infection (dpi) by clinical signs; virological, biochemical and haematological parameters; and liver histopathology. The tacrolimus blood levels were monitored throughout the experiment. Immunosuppression was confirmed by clinical and laboratorial findings, such as: moderate weight loss, alopecia, and herpes virus opportunistic infection. In this study, chronic HEV infection was characterized by the mild increase of liver enzymes serum levels; persistent RNA viremia and viral faecal shedding; and liver histopathology. Three out of four immunosuppressed monkeys showed recurrent HEV RNA detection in liver samples, evident hepatocellular ballooning degeneration, mild to severe macro and microvesicular steatosis (zone 1), scattered hepatocellular apoptosis, and lobular focal inflammation. At 69 dpi, liver biopsies of all infected monkeys revealed evident ballooning degeneration (zone 3), discrete hepatocellular apoptosis, and at most mild portal and intra-acinar focal inflammation. At 160 dpi, the three chronically HEV infected monkeys showed microscopic features (piecemeal necrosis) corresponding to chronic hepatitis in absence of fibrosis and cirrhosis in liver parenchyma. Within 4-months follow up, the tacrolimus-immunosuppressed cynomolgus monkeys infected with a Brazilian swine HEV-3 strain exhibited more severe hepatic lesions progressing to chronic hepatitis without liver fibrosis, similarly as shown in tacrolimus-immunosuppressed solid organ transplant (SOT) recipients. The cause-effect relationship between HEV infection and tacrolimus treatment was confirmed in this experiment.

Understanding the mechanisms which regulate HCMV latency could allow therapeutic targeting of the latent virus reservoir from where virus reactivation can cause severe disease. We show that the BMPR2/TGFbeta receptor/YY1 signaling axis is crucial to maintain HCMV latency in undifferentiated cells and that pharmacological reduction of BMPR2 in latently infected cells leads to reactivation of the viral lytic transcription program, which renders the infected cell open to immune detection and clearance in infected individuals.

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The development of nanovehicles for intracellular drug delivery is strongly bound to the understating and control of nanoparticles cellular uptake process, which in turn is governed by surface chemistry. In this study, we explored the synthesis, characterization, and cellular uptake of block copolymer assemblies consisting of a pH-responsive poly[2-(diisopropylamino)ethyl methacrylate] (PDPA) core stabilized by three different biocompatible hydrophilic shells (a zwitterionic type poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) layer, a highly hydrated poly(ethylene oxide) (PEO) layer with stealth effect, and an also proven nontoxic and nonimmunogenic poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) layer). All particles had a spherical core-shell structure. The largest particles with the thickest hydrophilic stabilizing shell obtained from PMPC-b-PDPA were internalized to a higher level than those smaller in size and stabilized by PEO or PHPMA and produced from PEO-b-PDPA or PHPMA-b-PDPA, respectively. Such a behavior was confirmed among different cell lines, with assemblies being internalized to a higher degree in cancer (HeLa) as compared to healthy (Telo-RF) cells. This fact was mainly attributed to the stronger binding of PMPC to cell membranes. Therefore, cellular uptake of nanoparticles at the sub-100 nm size range may be chiefly governed by the chemical nature of the stabilizing layer rather than particles size and/or shell thickness.

Glioblastoma multiforme is the most prevalent and malignant tumor of the central nervous system. In the last few years, accumulating evidence has suggested an association between human cytomegalovirus (HCMV) infection and glioblastoma multiforme. In this study, tumor tissues and peripheral blood of patients with glioblastoma multiforme were examined for the presence of HCMV DNA. Twenty-two fresh surgical brain specimens and 20 peripheral blood samples were analyzed by real-time PCR (qPCR) and hemi-nested PCR (nPCR) for the presence of pp65 and (glycoprotein B) gB viral genomic regions, respectively. HCMV DNA was detected in the majority of the tumor samples analyzed (95% by qPCR and 91% by nPCR). About half of the patients with tumors positive for HCMV also had detectable viral DNA in their peripheral blood (47% by qPCR and 61% by nPCR). Genome copy numbers were determined and in the majority of the tumor samples cellular DNA outnumbers viral DNA (average of 1 infected cell in 33 cells). The gB genotypes were determined in HCMV-positive samples and gB2 was the most prevalent genotype in the tumor and blood samples. The results show a high prevalence of HCMV in glioblastoma multiforme samples reinforcing a possible association between HCMV infection and tumor development.