Seroprevalence of hantaviruses in small wild mammals trapped in South Korea from 2005 to 2010.

The seroprevalence of Hantaan virus (HTNV) in wild rodents in South Korea was analyzed. Wild rodents were trapped in 18 cities in eight provinces during 2005-2007 and on three islands and four mountains during 2008-2010. Sera were collected from 629 out of 933 trapped wild animals and examined for immunoglobulin G antibodies to HTNV using indirect immunofluorescence assays. Apodemus agrarius (80.1%) was the most frequently captured species at almost all trapping sites. The overall prevalence of HTNV antibodies was 0.26 (162/629). Seropositive individuals were more frequent in cities (32.2%, n=410) than on islands (14.0%, n=57) or mountains (13.6%, n= 162). HTNV antibody-positive rate was higher in the fall (29.6%, n=253) than in the spring (23.1%, n=376). A. agrarius had the highest prevalence of HTNV antibodies (26.9%, n=561) of all tested species. Considering all the individuals, the prevalence of HTNV antibodies was higher in males (29.2%, n=250) than in females (22.3%, n=305). Our results show that HTNV is widely distributed throughout South Korea, and that HTNV infection of wild rodents is affected by their habitat, species, sex, and season.

The soluble amino-terminal region of HVEM mediates efficient herpes simplex virus type 1 infection of gD receptor-negative cells.

BACKGROUND: Previous studies from our own and other labs reported the surprising finding that the soluble V domain of the herpes simplex virus type 1 (HSV-1) entry receptor nectin-1 can both block HSV infection of receptor-bearing cells and mediate infection of receptor-deficient cells. Here we show that this property is not unique to nectin-1. We generated a pair of truncated, soluble forms of the other major HSV-1 entry receptor, herpes virus entry mediator (HVEM or HveA), and examined its effects on HSV-1 infection of receptor-deficient cells. RESULTS: In cultures of CHO-K1 cells, sHveA102 comprising the two amino-terminal cysteine-rich pseudorepeats (CRPs) of HVEM enabled infection of greater than 80% of the cells at an MOI of 3, while sHveA162 comprising the complete ectodomain failed to mediate infection. Both sHveA102 and sHveA162 blocked infection of CHO-K1 cells stably expressing HVEM in a dose-dependent manner, indicating that both were capable of binding to viral gD. We found that sHveA102-mediated infection involves pH-independent endocytosis whereas HSV infection of HVEM-expressing CHO-K1 cells is known to be pH-dependent. CONCLUSIONS: Our results suggest that the C-terminal portion of the soluble HVEM ectodomain inhibits gD activation and that this effect is neutralized in the full-length form of HVEM in normal infection.

Prevalence of hantavirus infection in wild rodents from five provinces in Korea, 2007.

Hemorrhagic fever with renal syndrome (HFRS) is an infectious disease caused by hantaviruses of the family Bunyaviridae. Among them, Hantaan virus (HTNV) is most widely distributed in Korea. The striped field mouse, Apodemus agrarius, is the natural host of HTNV in rural Korea. We trapped 766 small mammals of three species (1 Eothenomys regulus, 13 Crocidura suaveolens, and 752 Apodemus agrarius) in five provinces in Korea from January to December 2007. We tested 542 rodent sera for HTNV antibodies by an indirect immunofluorescent assay (IFA), finding antibody prevalences of 4 to 29% among the five provinces. Peaks in monthly antibody prevalence occurred in spring and fall. Antibody prevalence during the second peak coincided increased HFRS incidence in autumn. We used multiplex reverse transcription polymerase chain reaction (RT-PCR) to detect the partial S segment of Hantaan, Seoul, and Puumala viruses in 766 lung samples of all captured animals and found HTNV RNA in 25 A. agrarius. Two isolates of HTNV were obtained from PCR-positive A. agrarius by cultivation in Vero E6 cells. This first systemic survey of monthly antibody prevalence in hantavirus hosts in wide regions in Korea could provide useful information for other researchers studying environmental and ecological factors affecting HFRS.

Phosphorylation and transactivation of Pax6 by homeodomain-interacting protein kinase 2.

Pax6 is a transcriptional activator that contains two DNA binding domains and a potent transcription activation domain in the C terminus, which regulates organogenesis of the eye, nose, pancreas, and central nervous system. Homeodomain-interacting protein kinase 2 (HIPK2) interacts with transcription factors, including homeoproteins, and regulates activities of transcription factors. Here we show that HIPK2 phosphorylates the activation domain of Pax6, which augments Pax6 transactivation by enhancing its interaction with p300. Mass spectrometric analysis identified three Pax6 phosphorylation sites as threonines 281, 304, and 373. The substitutions of these threonines with alanines decreased Pax6 transactivation, whereas substitutions to glutamic acids increased transactivation in mimicry of phosphorylation. Furthermore, the knock-down of either endogenous or exogenous HIPK2 expression with HIPK2 shRNA markedly inhibited Pax6 phosphorylation and its transactivating function on proglucagon promoter in cultured cells. These results strongly indicate that HIPK2 is an upstream protein kinase for Pax6 and suggest that it modulates Pax6-mediated transcriptional regulation.