Seroepidemiological Survey of Hemorrhagic Fever with Renal Syndrome in Korea , 1994 - 1996

To understand the seroepidemiological patterns of haemorrhagic fever with renal syndrome in Korea, a nation-wide survey collaborated with fourteen clinics was carried out from 1994 to 1996. Sera of 4,547 patients with acute febrile episodes were tested by indirect immunofluorescent antibody test and the seroepidemiological analysis including sex, age, seasonal and regional distributions were performed. According to the results obtained in this study, the epidemiological characteristics of haemorrhagic fever with renal syndrome in Korea were summarized as follows: 1. Seropositive rate of hemorrhagic fever with renal syndrome among the patients with acute febrile episodes was 6.4% by the cut-off point of 1:40. 2. Among the seropositives, male outnumbered female and the ratio of males to females was 2.0:1.0. 3. Seventy six % of the seropositive patients were 21-60 years old. 4. The number of seropositive cases increased from October and reached maximum in December and began to decrease gradually from January. 5. The geographical distribution of the seropositives cover most areas including Cheju province in Korea.

The Change of c-jun Promoter Activity in TPA-Induced U937 Cells Infected with Human Cytomegalovirus (HCMV)

Transient transfection assay has been done to evaluate whether the c-jun activation would be prerequisite to the induction of permissiveness against human cytomegalovirus using in vitro cell model in which U937 has been induced to express CD11b and CDl4 to become potential monocyte/macrophage cells by TPA treatment. U937 cells were treated with 10 microM, 50 microM or 100 microM of TPA. The cell morphology change was observed and the expression of the CD11b and CDl4 was confirmed by FACS. Differentiated cells were transfected with pJLuc reporter vector which contained the wild type murine c-jun promoter spanning the SP1, CTF, ATF/CREB and MEF-2 binding sites upstream of the firefly luciferase gene. After 48 hrs of transfection, the cells were infected with HCMV Towne strain and the luciferase activity was assessed at 1 h and 4 h pi. The transfection assay showed no activation of the c-jun promoter at 1 h pi, instead, it showed 2 times increase of the its activity at 4 h pi. There was no difference of the c-jun promoter activation between TPA treated and untreated U937 cells, implying that c-jun activation might not be prerequisite for allowing cells to be premissive to HCMV, although HCMV infection itself could activate c-jun promoter.

The Change of c-jun Promoter Activity in TPA-Induced U937 Cells Infected with Human Cytomegalovirus (HCMV)

Transient transfection assay has been done to evaluate whether the c-jun activation would be prerequisite to the induction of permissiveness against human cytomegalovirus using in vitro cell model in which U937 has been induced to express CD11b and CDl4 to become potential monocyte/macrophage cells by TPA treatment. U937 cells were treated with 10 microM, 50 microM or 100 microM of TPA. The cell morphology change was observed and the expression of the CD11b and CDl4 was confirmed by FACS. Differentiated cells were transfected with pJLuc reporter vector which contained the wild type murine c-jun promoter spanning the SP1, CTF, ATF/CREB and MEF-2 binding sites upstream of the firefly luciferase gene. After 48 hrs of transfection, the cells were infected with HCMV Towne strain and the luciferase activity was assessed at 1 h and 4 h pi. The transfection assay showed no activation of the c-jun promoter at 1 h pi, instead, it showed 2 times increase of the its activity at 4 h pi. There was no difference of the c-jun promoter activation between TPA treated and untreated U937 cells, implying that c-jun activation might not be prerequisite for allowing cells to be premissive to HCMV, although HCMV infection itself could activate c-jun promoter.

Analysis of antigenic characteristics of Rickettsia tsutsugamushi Boryong strain and antigenic heterogeneity of Rickettsia tsutsugamushi using monoclonal antibodies

Twenty-four monoclonal antibodies were produced by immunizing BALB/c mice with Rickettsia tsutsugamushi Boryong strain and used for the analysis of antigenic characteristics of R.tsutsugamushi Boryong strain and antigenic heterogeneity of R.tsutsugamushi by indirect immunofluorescent(IF) test. R. tsutsugamushi Kato, Karp, Gilliam, TA686, TA716, TA763, TC586, TH1817, and Boryong were used for the analysis of antigenic heterogeneity of R.tsutsugamushi. Five monoclonal antibodies were reactive with 27-kDa protein, four monoclonal antibodies were reactive with 47-kDa protein, and eight monoclonal antibodies were reactive with 56-kDa protein of R.tsutsugamushi Boryong strain. The reactive protein of seven monoclonal antibodies could not be identified by immunoblotting method. All monoclonal antibodies to 27-kDa protein and three monoclonal antibodies to 47-kDa protein, and five monoclonal antibodies to 56-kDa protein were reactive with three to eight strains among nine strains of R. tsutsugamushi tested. One monoclonal antibody reactive to 47-kDa protein(KI18) and two monoclonal antibodies reactive to 56-kDa protein(KI36, and KI37) reacted with all the strains of R. tsutsugamushi tested. Strain-specific monoclonal antibody(KI58) could be found among antibodies which were reactive with 56-kDa protein. There was no strain which showed same reactivity pattern to these 24 monoclonal antibodies among nine strains. From this results, it could be concluded that Boryong strain is antigenically different from other strains of R.tsutsugamushi and antigenic heterogeneity of R.tsutsugamushi is due to the antigenic diversity of several proteins of R. tsutsugamushi including 56-kDa protein.

Significance of IgG and IgM antibodies in the diagnosis of scrub typhus and evaluation of rickettsia tsutsugamushi strain Boryong as a diagnostic antigen

No abstract available.

Significance of IgG and IgM antibodies in the diagnosis of scrub typhus and evaluation of rickettsia tsutsugamushi strain Boryong as a diagnostic antigen

No abstract available.