바이러스 감염에 대한 면역반응

황응수,박정규,차창용 대한면역학회 2004 Immune Network Vol.4 No.2

Viruses are obligate intracellular parasites which cause infection by invading and replicating within cells. The immune system has mechanisms which can attack the virus in extracellular and intracellular phase of life cycle, and which involve both non-specific and specific effectors. The survival of viruses depends on the survival of their hosts, and therefore the immune system and viruses have evolved together. Immune responses to viral infection may be variable depending on the site of infection, the mechanism of cell-to-cell spread of virus, physiology of the host, host genetic variation, and environmental condition. Viral infection of cells directly stimulates the production of interferons and they induce antiviral state in the surrounding cells. Complement system is also involved in the elimination of viruses and establishes the first line of defence with other non-specific immunity. During the course of viral infection, antibody is most effective at an early stage, especially before the virus enters its target cells. The virus- specific cytotoxic T lymphocytes are the principal effector cells in clearing established viral infections. But many viruses have resistant mechanism to host immune responses in every step of viral infection to cells. Some viruses have immune evasion mechanism and establish latency or persistency indefinitely. Furthermore antibodies to some viruses can enhance the disease by the second infection. Immune responses to viral infection are very different from those to bacterial infection. (Immune Network 2004;4(2):73-80) 바이러스는 세포 내 절대 기생체로서 세포에 침투하여 복제하여 증식한다. 면역계는 바이러스가 세포 밖에 존재하는 시기와 세포 내에 있는 시기 모두 공격을 할 수 있으며, 비특이적으로나 특이적인 반응을 보인다. 바이러스의 궁극적인 생존은 숙주의 생존 여부에 달려 있으므로 숙주의 면역체계와 바이러스는 상호 진화하여 왔다. 바이러스 감염에 대한 면역반응은 감염부위, 세포 간 바이러스의 전파기전, 숙주의 생리학적 상태, 유전적 소인과 환경요인에 따라 매우 다양하게 나타난다. 바이러스 감염은 인터페론의 생산을 유도해서 항바이러스 상태를 유발하고, 보체의 작용 등 선천면역에 의해 일차적으로 방어된다. 항체는 감염 초기 단계에 바이러스가 표적세포에 침투하기 전에는 매우 효과적으로 항바이러스 기능을 발휘한다. 확립된 바이러스 감염을 제거하고 완결시키는 데는 세포독성 T 림프구가 결정적인 역할을 한다. 그러나 바이러스는 이와 같은 단계별 숙주의 방어기전에 대항하는 기전을 갖고 있어서 바이러스에 따라서는 평생 숙주의 몸에서 잠복 또는 지속 감염을 이루게 된다. 한편 면역반응이 형성된 경우에 재감염이 되면 오히려 증상을 악화시키는 경우도 있는 등 바이러스 감염에 대한 면역반응의 특성은 다른 세균 등의 면역반응과 상당히 다른 점이 있다.

Concanavalin A가 細胞性免疫反應과 體液性免疫反應에 미치는 影響 : 마우스의 T依存性 體液免疫反應에 대한 Con A의 抑制作用 Suppression of a thymus Dependent Humoral Response by Con A in Mice

張友鉉,金翼詳,李明洙,崔明植 大韓免疫學會 1981 大韓免疫學會誌 Vol.3 No.1

Mice treated with Con A 1 or 2 days prior to primary immunization with SRBC exhibited a significai.F suppression of direct PFC response. This immunosuppressive effect could be reversed by using higher doses of antigen designad to by pass T-cell function. Normal syngeneic recipient mice transferred with Con A-activated spleen cells showed a suppression of primary direct PFC response on day 6. Recipients transferred with Con A-activated thymocytes showed no effect on direct PFC responses. It is suggested that Con A induced immunosuppression of thymus-dependent humoral immune response in mice is at least partly due to the activation of a subpopulation of thymus derived cells, of which tissue source is not thymus but spleen, and that the effect is short-lived and the suppressive effect of HIR is marked in late stage.

Suppression of the Ly6 Antigens Expression on P815 Mastocytoma Cells by Expressing Antisense RNA

Sonn, Chung Hee,Park, Mee Rang,Kim, Young Sang 大韓免疫學會 1993 大韓免疫學會誌 Vol.15 No.-

Ly6항원은 T세포, B세포, 대식세포와 같은 여러 면역기능을 담당하는 세포의 표면에 g1ycosy1 phosphatidylinositol결합형태로 발현된다. 활성화된 대식세포와 T 림파구는 보다 증가된 Ly6항원의 발현을 보여준다. 여러 다른 면역세포에서 이 항원의 정확한 기능을 연구하기 위하여, antisense RNA 기법을 이용하여 Ly6항원의 발현이 억제된 세포를 얻고자 시도하였다. DBA/2생쥐(H-2^(d))에서 기원된 mastocytoma인 P8l5세포를 pNeoSRαⅡ-Ly6(-)백터, 또는 pFRSVSRα-Ly6(-)와 pSV2neo plasmid DNA로 유전자 전달을 행하였다. 15개의 G4l8에 대한 저항성을 갖는 clone을 얻었으며, 이들을 flew cytometry분석과 Southern blot분석을 하였다. Southern blot으로 분석한 6개의 clone들 모두가 Ly6 cDNA를 갖고 있으며, 또한 neomycin resistance유전자를 갖고 있음이 밝혀졌다. 모든 클를을 FACS분석법으로 Ly6항원의 발현을 조사한 결과, 한 클론이 Ly6항원의 발현이 현저히 억제된 것으로 밝혀졌다. 이 클론은 CTL에 대한 민감성과 allo-MHC반응을 유도하는 능력을 비교하는데 이용될 것이다.

위암에서 Galectin-3 단백질 발현에 관한 연구

주홍구,우희종 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.4

The expression of galectin-3 protein in four different gastric cancer cell lines and lymph node tissues of patients with gastric carcinoma was studied by Western blotting, immundhistochenustry and flow cytometry analysis. Western blot analysis of galectin-3 using anti-galectin-3 , mAb indicated that a 29 kDa protein was expressed in 3 gastric cancer cell lines, AGS, KATO BI , and SNU16, but not in SNU1 which was a non-adherent cell line. Interestingly, SNU16 cells secreted galectin-3 into the culture media. Flow cytometry analysis revealed that NIH3T3, AGS, and KATO III cells expressed the galectin-3 on the cell surface. The level a))' galectin-3 expression was highest in AGS (91.5%), high in KATO M (69.5%), and low in NIH3T3 (55.8%). The gastric cancer cells metastasized into .lymph node tissues were heavily stained whereas normal lymphocytes were not stained. This study suggested that the expression of galectin-3 and the metastasis of gastric cancer cells might be correlated.

Expression of a Human Monoclonal IgG Fab Molecule in Sf9 Insect Cells

Cha, Sanghoon 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.3

SP4는 인간 단일세포성 IgG Fab 분자로서 자가면역 간질환인 일차담관성 간경화(primary biliary cirrhosis) 환자의 임파절로 부터 제작된 조합 항체 library를 검색하여 획득되어진 후 대장균(E. coli)에서 발현, 생산되어지고있으며 일차 담관성 간경화의 주요 자가항원(autoantigen)인 pyruvate dehydrogenase complex-E2 (PDC-E2)에 특이적으로 반응하는 유전자 재조합 항체이다. 본 연구에서는 SP4의 생산량을 증대시키기 위하여 SP4 항체유전자의 조작을 통해 baculovirus 발현 vector에 클로닝한 후 Sf9 곤충세포(insect cell)에서 발현하였다. 곤충세포에서 생산된 인간 단일세포성 항체는 항원 반응 특이성을 정상적으로 유지하였으며 대장균 발현 체계와 비교해 볼때 많은 항체생산량의 증가가 관찰되었다. 곤충세포에서의 인간항체 발현은 포유류세포를 이용하는 것에 비하여 그 생산단가가 저렴하고 또한 생산량이 증가됨으로 앞으로 기초의학 연구 및 임상 진단, 치료제로 활용될 수 있는 항체의 생산에 매우 유용하게 활용될 수 있을 것이다.

Euonymus alatus추출물의 실험적 당뇨발생 억제효과

김태중,송희종,소준노,이정호 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.4

Insulin-dependent diabetes mellitus (IDDM) is majorly caused by an immune system-mediated destruction of the beta cells in the islets of Langerhans. Patients with IDDM face major changes in lifestyle and the possibility of debilitating and life-threatening complications. In Korean traditional medicine, Euonymus alatus (EA) extract has been widely used for preventing and curing ulcer and inflammation. A previous study has shown that EA itself has an antidotic activities against inflammation, suggesting possibility that EA can exert this beneficial effects to IDDM by an initial protection against diabetes caused by pancreatic inflammation. The present study was undertaken to evaluate the prophylactic effect of EA extract on the diabetogenesis of streptozotocin (STZ) and alloxan (ALX), using animal model, and to explore the possible mechanisms of its antidiabetic activity. Multiple low doses of STZ (45 mg/Kg for 5 days) in ICR mice and single dose of ALX (60 mg/Kg) in SD rats induced high level of hyperglycemia (defined as plasma glucose level > 300 mg/dl) and remarkably diminished body weight. But, animals that received diabetogenic agents in combination withsEA were maintained plasma glucose level as a normal state ( < 150 mg/dl), and appeared in good health and had similar weights to those of normal control. These results strongly indicated that EA prevented and blocked diabetogenesis of chemicals. EA significantly inhibited the nitric oxide- and tumor necrosis factor-production of mouse peritoneal macrophages. However, EA enhanced interleukin 1 production of macrophages at lower concentration but not at higher. EA itself increased phagocytic activity of unstimulated monocytes, but it did completely block that activity of zymosan- or platelet activating factor-stimulated cells. Taken together, this study led to conclusion that EA itself has a significant prophylactic effects against diabetes, and also suggested that its antidiabetic effects might be manifested by the downregulation of inflammatory process in diabetogenesis.

Heligmosomoides polygyrus 감염 마우스의 비장세포로 부터 만든 Conditioned Supernatant의 면역억제작용

하대유,한병갑,김명선,고유승 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.3

Heligmosomoides polygyrus is gastrointestinal parasitic nematoda which is common parasire of wild rodents. The experimental infection with this parasite has been studied extensively in models of host-parasite interaction. The present study was undertaken to investigate both the effects of administration of conditioned supernatant or conditioned medium(CM) prepared from H. polygyrus-infected mice on the humoral and cellular immune responses in mice. Normal conditioned supernatant(NCM) was prepared from uninfected mouse splenocytes stimulated with Con A. Supematants conditioned by Con A-stimulated splenocytes of H. polygyrus -infected mice were prepared on different days post-infection, namely on day 6(HCM-D6), day 14 (HCMD14) and day 18 (HCM-D18) post-infection with H. polygyrus L3 larvae. Effects of NCM, HCM-D6, HCM-D14 and HCM-D18 on delayed-type hypersensitivity(DTH) to sheep red blood cells (SRBC), contact hypersensitivity to dinitrofluorobenzene (DNFB), hemagglutinin response to SRBC, ovalbumin (OVA)-induced active systemic anaphylaxis(ASA), and anti-OVA specific IgE were investigated. Effect of anti-IL-4 antibody (11B11) on immunoinhibitory action of HCMD18 in OVA-induced ASA was also investigated. It was found that the administration into mice of HCM-D6, HCM-D14 or HCM-D18 significantly suppressed DTH to SRBC, contact hypersensitivity to DNFB, hemagglutinin response compared with NCM. The degree of immunosuppressive activity of HCM was less marked in HCM-D6 than HCM-D14 and HCM-D18. Interestingly, HCM-D18 prepared from ICR mouse strain also showed the profound suppression of OVA-induced ASA in BALB/c and C57BL/6 mouse strains as well as in ICR mice. ASA-inhibitory activity of HCM-D18 was Somewhat abrogated in terms of mouse mortality when mice were treated in the combination of HCM-D18 and anti-IL-4 antibody, indicating that IL-4 may play a role, at least in part, in the inhibitory activity of HCM. Taken together, the present study may be the first to demonstrate that conditioned supernatants prepared from the spleen cells of H. polygyrus-infected mice may suppress the in vivo humoral and cellular immyne responses to heterologous antigens, particularly fatal anaphylaxis induced by OVA, strongly suggesting that

IL-1 수용체를 통한 T세포 활성화에 Genistein 과 Staurosporin이 미치는 영향

한미영,윤도영,오은숙,고우석,윤선영,정태화 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.4

Stimulation of T-cells through TCR/CD3 complex alone is known to be not enough but also require a costimulatory signal, such as IL-1 stimulation. to induce IL-2 production. In this report, we studied the differential effects of staurosporin (a PKC inhibitor) and genistein (a PTK inhibitor) on the IL-2 production by EL-4 and A2.5 cells, to determine which pathway is responsible for IL-1 receptor signal transduction. While staurosporin suppressed the IL-2 production induced in EL-4 cells upon PMA stimulation but not upon PHA plus IL-1, genistein inhibited the IL-2 production induced by PHA plus IL-1 but not by PMA. Genistein also completey abrogated the IL-2 production by A2.5 cell when stimulated with PHA and IL-1. These results suggest that the costimulatory signal by IL-1, which leads to IL-2 production and proliferation, is closely linked to the PTK activity in T cells.

대장균에서 대량 생산한 B형 간염바이러스 X 단백질의 발현 특성

정미경,민성식,이희구,오은숙,이혜경,이태규,임종순,박순희 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.4

The X protein of human hepatitis B virus (HBx) consists of 154 amino acids and transactivates various cellular and viral promoters and enhancers. This protein has been also implicated in virus-mediated oncogenesis of hepatocytes. However, there are still controversial reports on its mechanism related to its oncogenicity. To elucidate the presence of any correlation between immune responses against HBx protein and hepatitis pathogenicity, convenient sources for recombinant HBx protein and anti-HBx antibodies are necessary. Three recombinant vectors were constructed to express the X open reading frame (ORF) of hepatitis B virus in E. coli. Recombinant E. coli transformed with one of these plasmid, pET- AX plasmid, which containd X ORF deleted in N-terminus, did not produce HBx protein. However, when X ORF containing 154 amino acids was cloned in pET, the HBx protein was produced. A GST fusion protein containing 146 amino acids encoded by ORF X was also successfully expressed. This protein was produced in large quantities of more than-60% of total proteins However, nonfused HBx protein was produced in small quantities. As both proteins were produced in inclusion bodies, HBx recombinant GST-fusion protein was further proccessed for purification. GST-X fusion protein was solubilized by sarkosyl. The solublized protein was purified by affinity to glutathione sepharose bead. The purified HBx protein was fairly good immunogen eliciting good humoral immune responses in mice. We produced polyclonal antibodies against HBx recombinant proteins and confirmed the specificity of the antibodies.

마우스(H-2K^(b))에서 간염 바이러스 핵 항원에 의한 CTL유도

김재화,이희구,이기영,임종석,김용호,박순희,최용경,정태화,최인성,김길현 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.2

Recently reported viral peptides from virus-infected cells that are bound to class I MHC molecules showed 8-lOmer sequences and typical dominant anchor residues. Using the mutant tumor line RMA-S, which expresses its surface H-2K' molecules devoid of peptides, we investigated the specific CTL epitopes on the hepatitis B viral surface and core proteins that were isolated from hepatitis B virus-infected patients. This was done by examining the ability of randomly trypsinized protein to bind to H-2K' or Db molecule on RMA-S cells. The trypsin-treated proteins enhanced the expression of H-2b molecules on RMA-S cells. We have analyzed the digested proteins by high performance liquid chromatography, and binding assays with respective peptide fractions showed the presence of H-2' binding epitopes on hepatits B viral protein. These findings suggest that it is possible to determine the epitope sequences directly by measuring their binding to class I molecules followed by analyzing their amino acid sequences.