• IMMUNE NETWORK
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• 제14권4호
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• pp.187-200
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• 2014

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are the most common cause of genital ulceration in humans worldwide. Typically, HSV-1 and 2 infections via mucosal route result in a lifelong latent infection after peripheral replication in mucosal tissues, thereby providing potential transmission to neighbor hosts in response to reactivation. To break the transmission cycle, immunoprophylactics and therapeutic strategies must be focused on prevention of infection or reduction of infectivity at mucosal sites. Currently, our understanding of the immune responses against mucosal infection of HSV remains intricate and involves a balance between innate signaling pathways and the adaptive immune responses. Numerous studies have demonstrated that HSV mucosal infection induces type I interferons (IFN) via recognition of Toll-like receptors (TLRs) and activates multiple immune cell populations, including NK cells, conventional dendritic cells (DCs), and plasmacytoid DCs. This innate immune response is required not only for the early control of viral replication at mucosal sites, but also for establishing adaptive immune responses against HSV antigens. Although the contribution of humoral immune response is controversial, $CD4^+$ Th1 T cells producing IFN-${\gamma}$ are believed to play an important role in eradicating virus from the hosts. In addition, the recent experimental successes of immunoprophylactic and therapeutic compounds that enhance resistance and/or reduce viral burden at mucosal sites have accumulated. This review focuses on attempts to modulate innate and adaptive immunity against HSV mucosal infection for the development of prophylactic and therapeutic strategies. Notably, cells involved in innate immune regulations appear to shape adaptive immune responses. Thus, we summarized the current evidence of various immune mediators in response to mucosal HSV infection, focusing on the importance of innate immune responses.

• 대한미생물학회지
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• 제34권5호
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• pp.435-443
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• 1999

Orientia tsutsugamushi is obligate intracellular bacterium that grows within the cytoplasm of the eukaryotic host cells. Therefore capability of the attachment, entry into the host cell and intracellular survival should be critical process for oriential infection. In this study we investigated the cellular invasion mechanism of Orientia tsutsugamushi and the role of transmembrane heparan sulfate proteoglycan, which binds diverse components at the cellular microenvironment and is implicated as host cell receptors for a variety of microbial pathogens. First of all Orientia tsutsugamushi can invade a wide range of nonprofessional phagocytic cells including fibroblast, epithelial cells and endothelial cells of various host species, including Band T lymphocytes. Thus, it was postulated that the attachment of O. tsutsugamushi requires the recognition of ubiquitous surface structures of many kinds of host cells. Treatments with heparan sulfate and heparin inhibited the infection of Orientia tsutsugamushi in dose-dependent manner for L cell, mouse fibroblast, whereas other glycosaminoglycans such as chondroitin sulfate had no effect. Collectively, these findings provide strong evidence that initial interaction with heparan sulfate proteoglycan is required for the oriential invasion into host cells.

• 한국잠사곤충학회지
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• 제37권1호
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• pp.52-56
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• 1995

Baculovirus 발현계에서 BmNPV의 증식효율을 향상시키기 위하여, 누에 유충 체액의 BmN-4 세포주에서 BmNPV 증식에 미치는 영향을 조사하였다. 5령 3일째의 누에 유충으로 부터 체액을 추출하여 BmN-4 배양액에 첨가한 결과, 열처리하지 않은 누에 체액의 첨가는 세포의 응집과 소형화 현상으로 인해 세포의 증식을 저해한 반면, $65^{\circ}C$에서 30분간 열처리한 체액 10%와 FBS 3%를 세포배양액에 첨가한 것이 바이러스 감염에 의해 방출된 다각체의 수가 가장 많은 것으로 나타나 바이러스 증식에 가장 효과적이었다. 또한 plaque assay 결과, 체액의 첨가에 의한 바이러스 증식효율의 증가는 세포의 증식에 의한 것이라기보다 바이러스 감염성의 증가에 기인하는 것으로 보여진다.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.629-632
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• 2013

Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of $241.5{\pm}41.0$ for T. papuae, $432.6{\pm}48$ for T. pseudospiralis, and $528.6{\pm}20.6$ for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp.

• 한국동물위생학회지
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• 제14권2호
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• pp.110-120
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• 1991

28 porcine enteroviruses were isolated from 86 pig-feces of 9 swine farms located in south region, Chung-buk, from March to September 1990. Physico-chemical properties and pathogenicity of isolates were investigated. Results obtained throughout experiments are summarized as follows. According to the age, weanlings(40-90 days), sucklings(10-30 days) and adult pigs(6 months over) showed the isolation rate of 67%. 8% and 4%, respectively. By physico-chemical tests, YD-90/22, YD-90/43 and YD-90/64 strains were found to be ether, chloroform and PH stable. Nucleic acid test suggests the virus to have a DNA genome. Most of the Isolates were not evident of hemagglutinin using erythrocytes from various mammalian & avian. 22 strains among the isolates were shown CPE type I and the remainders were CPE type II. 3 strains among isolates of CPE type I strains were neutralized with high titers to serotype 2 antiserum. In the study on virus growth curve in PK-l5 cells, YD-90/22, YD-90/43 and YD-90/64 strains showed the maximum infectivity titers($10^{6.0}-l0^{6.5} TCID({50}ml$) at 4days post inoculation(PI). When 30 day-old commercial piglets were inoculated only intraoral route with the YD-90/22 strain at $10^{6.0} TCID_{50}ml,$ piglets not showed the symptoms. But piglets inoculated by intramuscle route, intraoral and intramuscle route after pretreat with dexamethasone(2.5mg /kg) for 5 days were shown the symptoms of anorexia, diarrhea, pyrexia and ataxia at 4th-6th days PI. The viral reisolation in the virus-inoculated piglets was examined from feces. The viruses were recovered intermittently from 2nd to 16th day PI and at 4th-6th day PI, all piglets excreted viruses.

• 미생물학회지
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• 제27권3호
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• pp.225-230
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• 1989

1983년 우리나라에서 처음으로 전염성췌장괴저 바이러스가 분리되기 시작한 이래 여러가지 종류의 내수며 양식 물고고기로부터 이 바이러스가 검출되어 왔다. 세계적으로 안정되고 있는 세가지 표준혈청형 즉 VR-299, Sp 그리고 Ab형 에 대한 중화항체 실험으로, 우리나라에서 발견되는 전염성췌장괴저 바이러스는 주로 VR-299형임이 확인되어 왔으나 대청댐에서 양식된 송어로부터 발견된 한 주의 바이러스는 독특한 혈청형을 보이고 있어 그 특성을 조사하였다. 이 바이러스로부터 단백질과 핵산을 분리하여 세가지 표준 혈청형 바이러스의 그것과 비교하여 본 결과, 크기에 있어 분명한 차이가 보였고 중화항체를 이용한 감염저지 실험으로 Sp 형과 비교적 가까운 연관관계를 가지는 거승로 밝혀졌으나, 세가지 표준 혈청과는 뚜렷이 구분되는 새로운 혈청형으로 판정되었다.

• 미생물학회지
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• 제22권1호
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• pp.41-48
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• 1984

아산 양어장에서 양식되고 있는 뱀장어 (Anguilla japonica)로부터 22주의 병원성 세균을 분리하여 그 생화학적 성질, 혈청학적 관계, 금붕어에 대한 감염성 및 여러 항생물질에 대한 감수성을 시험하였다. 22균주중 14주 (64%)는 Edwardsiella tarda 5주 (23%)는 Aeromonas hydrophila, 기타 3균주(14%)는 Vibrio anguillarum으로 동정되었다. 3가지 분리균중에서 E. tarda는 동일한 혈청형으로 그 분리율 및 금붕어에 대한 감염성이 가장 높았다. 이에 따라 E. tarda가 조사된 양어장의 뱀장어에서 발생하는 세균성 질병의 주 병원체로 판명되었다. 세 분리균주의 균액을 수조에 풀어 금붕어에 접촉시켰을 때 그 감염율은 세 균주 모두 상대적으로 낮았다. 10주의 분리균을 택해 12가지 항생물질에 대해 감수성 검사를 한 결과 하나에서 여섯가지 약제에 대해 저항성을 나타냈으며, 그 중 tetracycline 유도체와 sulfisoxazole에 대한 저항성이 현저하였다.

• 한국어병학회지
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• 제12권2호
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• pp.107-113
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• 1999

능성어의 바이러스성 신경괴사증 바이러스(fish nodavirus)의 병원성을 능성어 및 다른 해산어류를 대상으로 인위감염법에 의해 조사한 결과, 능성어 바이러스성 신경괴사증 바이러스는 능성어에서는 소형어(27 g)부터 대형어(104 g)까지 제사를 일으켜 강한 병원성을 나타냈지만, 실험에 사용한 크기의 방어(537 g), 참돔(207 g), 돌돔(43 g), 넙치(41 g), 자주복(27 g) 및 조피볼락(94 g)에는 폐사를 일으키지 않아 병원성을 나타내지 않았다. 그리고 사육수온별 능성어에 대한 바이러스의 병원성은 수온 $15^{\circ}C$에서는 병원성을 나타내지 않았고, 수온 $20\sim28^{\circ}C$에서는 수온이 높을 수록 병원성을 강하게 나타냈다. 그리고 바이러스는 근육주사, 복강 주사 및 경구감염뿐만 아니라 침지감염과 혼합사육감염에 의해서도 쉽게 능성어에 감염이 되지만, 감염 후 생존한 능성어에 대해서는 바이러스를 재감염시켜도 폐사가 일어나지 않았다.

• BMB Reports
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• 제34권2호
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• pp.176-181
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• 2001

Using a retrovirus, foreign genes can be introduced into mammalian cells. The purpose of this study is to produce a retrovirus that can make the infected cells express two genes; the human multidrug resistance gene (MDR1) and the HLA-B7 gene, which is one of the major human histocompatibility complex (MHC) class I genes. For the expression of these genes, the internal ribosome entry site (IRES) was used, which was derived from the encephalomyocarditis (EMC) virus. In order to produce retroviruses, a retroviral vector was transfected into a packaging cell line and the transfected cells were treated with vincristine, which is an anti-cancer drug and a substrate for the MDRI gene product. This study revealed that two genes were incorporated into chromosomes of selected cells and expressed in the same cells. The production of the retrovirus was confirmed by the reverse transcription (RT)-PCR of the viral RNA. The retrovirus that was produced infected mouse fibroblast cells as well as the human U937. This study showed that packaging cells produced the retroviruses, which can infect the target cells. Once the conditions for the high infectivity of retrovirus into human cells are optimized, thus virus will be used to infect hematopoietic stem cells to co-express MDRl and HLA-B7 genes, and develop the lymphocytes that can be used for the immnogene therapy.

• BMB Reports
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• 제39권1호
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• pp.55-60
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• 2006

We describe a phage display strategy, based on the differential resistance of proteins to denaturant-induced unfolding, that can be used to select protein variants with improved conformational stability. To test the efficiency of this strategy, wild-type and two stable variants of ${\alpha}_1$-antitrypsin (${\alpha}_1AT$) were fused to the gene III protein of M13 phage. These phages were incubated in unfolding solution containing denaturant (urea or guanidinium chloride), and then subjected to an unfavorable refolding procedure (dialysis at $37^{\circ}C$). Once the ${\alpha}_1AT$ moiety of the fusion protein had unfolded in the unfolding solution, in which the denaturant concentration was higher than the unfolding transition midpoint ($C_m$) of the ${\alpha}_1AT$ variant, around 20% of the phage retained binding affinity to anti-${\alpha}_1AT$ antibody due to a low refolding efficiency. Moreover, this affinity reduced to less than 5% when 10 mg/mL skimmed milk (a misfolding-promoting additive) was included during the unfolding/refolding procedure. In contrast, most binding affinity (>95%) remained if the ${\alpha}_1AT$ variant was stable enough to resist unfolding. Because this selection procedure does not affect the infectivity of M13, the method is expected to be generally applicable to the high-throughput screening of stable protein variants, when activity-based screening is not possible.