A 3-Month-Old Child with Acute Gastroenteritis with Enterovirus D68 Detected from Stool Specimen.

Enterovirus D68 (EV-D68) is known to be causative agent of mild to severe upper and lower respiratory illnesses in sporadic cases and outbreaks. We present a case report of a 3-month-old child with acute gastroenteritis who visited a pediatric clinic in Kyushu area in Japan in 2015. A stool sample collected from the patient was screened for diarrheal viruses by multiplex RT-PCR. The result showed that the sample was positive only for enterovirus, and EV-D68 clade B3 was identified by sequence analysis of the viral protein 1 gene. This study supports an association between EV-D68 infection and acute gastroenteritis.

Multiplex PCR for the Detection of 10 Viruses Causing Encephalitis/Encephalopathy and its Application to Clinical Samples Collected from Japanese Children with Suspected Viral.

BACKGROUND: Acute encephalitis is a serious neurological condition having a high mortality rate and affecting both children and adults. This study aimed to develop a multiplex PCR method for the simultaneous screening of clinical samples for the presence of the 10 viruses presently considered as the major viral causes of acute encephalitis/ encephalopathy in Asia. METHODS: Using previously published primers that have been widely used to screen for herpes virus-6, influenza A virus, human parechovirus, herpes simplex viruses 1 and 2, Japanese encephalitis virus, group A rotavirus, enterovirus, adenovirus, and dengue virus in clinical samples, a single-tube multiplex PCR assay was developed and was tested for its sensitivity and specificity. The method was then applied to screen 57 clinical samples, consisting of 13 fecal samples, 5 throat swabs, 3 post-nasal swabs, 18 serum samples, and 18 cerebrospinal fluid (CSF) samples, collected from 18 hospitalized Japanese children with suspected viral encephalitis/encephalopathy for the target viruses, and the results were compared with those of a monoplex PCR method. RESULTS: Positive viral controls of the 10 viruses were correctly typed using this multiplex PCR method. The multiplex PCR method showed high specificity with no unspecific amplification to non-target viruses. The results of applying this PCR method for screening clinical samples showed that 6 fecal samples, 2 serum samples, and 1 CSF sample collected from 7 patients were positive for a virus, specifically group A rotavirus (4 patients, 22.2%), enterovirus (2 patients, 11.1%), or adenovirus (1 patient, 5.6%). In comparison with monoplex PCR, for group A rotavirus, enterovirus, and adenovirus, the sensitivity of this multiplex PCR method decreased for serum, cerebrospinal fluid, and throat swab samples. CONCLUSIONS: This newly developed multiplex PCR method is a simple, rapid diagnostic tool and can be used to screen clinical samples for viruses causing acute encephalitis/encephalopathy in children in Asian countries.

High Mobility Group Box 1 Protein Enhances HIV Replication in Newly Infected Primary T Cells.

BACKGROUND: High-mobility group box 1 (HMGB1), a DNA-binding protein, has recently been shown to have effects on HIV replication, but the effects are dependent on the cell type and the timing of infection. Using human primary T cells, this study aimed to investigate the role of HMGB1 in HIV-1 replication in newly infected cells. METHODS: Human primary T cells were infected with the HIV-1 LAI (X4) strain and then cultured in the presence of recombinant HMGB1 protein or an anti-HMGB1 antibody at various concentrations. At the indicated time points, HIV-1 p24 concentrations in the culture media were measured by ELISA. Cell proliferation, basal HMGB1 concentration, and CD3, CD4, CXCR4, and receptor for advanced glycation end products (RAGE) expression were also examined. RESULTS: Recombinant HMGB1 could enhance HIV replication in newly infected primary T cells. In the presence of an anti-HMGB1 antibody (5 µg/mL or higher), significantly lower concentrations of HIV-1 p24 were observed in the cultures of primary T cells during the post-infection period. CONCLUSIONS: The data presented suggest that HMGB1 plays a role in the enhancement of HIV-1 replication in newly infected T cells. This finding provides useful information toward understanding HIV pathogenesis and for the development of new therapeutic strategies.

H1N1/09 influenza A virus infection of immortalized first trimester human trophoblast cell lines.

PROBLEM: Although high maternal mortality was reported in the most recent pandemic of swine-origin influenza A H1N1/09 (H1N1/09), its direct effects on the feto-placental unit are unknown. In the present study, we examined the susceptibility of immortalized human trophoblasts to clinical isolates of pandemic 2009 H1N1 influenza A (H1N1/09) virus. METHOD OF STUDY: The H1N1/09 virus was isolated from a patient with influenza, sequenced and identified as the A/Narita/2009 (H1N1) strain. The trophoblast cell lines Swan71 and HTR8 were challenged with the virus and examined for the expression of H1N1/09 viral RNA and proteins. RESULTS: Viral RNA and proteins were observed 24 hr after inoculation. However, viral release was not detected. CONCLUSION: First trimester human trophoblast cell lines were susceptible to the H1N1/09 influenza A virus. However, viral release and cytopathic effects were minimal. Our data suggest that placental damage by the H1N1/09 virus may be limited.