• 제목/요약/키워드: T-lymphocyte activation

검색결과 95건 처리시간 0.028초

T Lymphocyte Development and Activation in Humanized Mouse Model

  • Lee, Ji Yoon;Han, A-Reum;Lee, Dong Ryul
    • 한국발생생물학회지:발생과생식
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    • 제23권2호
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    • pp.79-92
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    • 2019
  • Humanized mice, containing engrafted human cells and tissues, are emerging as an important in vivo platform for studying human diseases. Since the development of Nod scid gamma (NSG) mice bearing mutations in the IL-2 receptor gamma chain, many investigators have used NSG mice engrafted with human hematopoietic stem cells (HSCs) to generate functional human immune systems in vivo, results in high efficacy of human cell engraftment. The development of NSG mice has allowed significant advances to be made in studies on several human diseases, including cancer and graft-versus-host-disease (GVHD), and in regenerative medicine. Based on the human HSC transplantation, organ transplantation including thymus and liver in the renal capsule has been performed. Also, immune reconstruction of cells, of the lymphoid as well as myeloid lineages, has been partly accomplished. However, crosstalk between pluripotent stem cell derived therapeutic cells with human leukocyte antigen (HLA) mis/matched types and immune CD3 T cells have not been fully addressed. To overcome this hurdle, human major histocompatibility complex (MHC) molecules, not mouse MHC molecules, are required to generate functional T cells in a humanized mouse model. Here, we briefly summarize characteristics of the humanized mouse model, focusing on development of CD3 T cells with MHC molecules. We also highlight the necessity of the humanized mouse model for the treatment of various human diseases.

A Three-step Method of Immunotoxicity Assessment

  • Lee, Jeong-Woon;Shin, Ki-Duk;Kim, Kap-Ho;Kim, Eun-Joo;Han, Sang-Seop;Jeong, Tae-Cheon;Koh, Woo-Suk
    • Toxicological Research
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    • 제16권4호
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    • pp.317-323
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    • 2000
  • The immunosuppressive effects of thirty nine chemicals chosen by their potential toxicity were evaluated using a three-step testing method. The immunotoxicity test method developed in this study consisted of three simple assays of lymphoproliferation, mixed leukocyte response, and interleukin (IL)-2 production. The first step was mitogen-induced proliferation assay. Ten chemicals showed the inhibitory effects on the mitogen (lipopolysaccharide or concanavalin A)-induced proliferation in dose-dependent manners. The second step was mixed lymphocyte response. This step crosschecked the growth-suppressive effects detected at the first step. All of 10 chemicals, which showed suppression of lymphoproliferation, also exhibited the suppressive effects on the mixed lymphocyte response in the similar range of chemical concentration. The third step was planned to determine whether or not this growth suppression was mediated through an early activation of T-cell, which could be represented with IL-2 production. Six out of 10 chemicals decreased the interleukin-2 production in the similar concentration range used in the step 1 and 2. These results suggest that those 6 chemicals might have their targets on the signal transduction path-way toward the IL-2 production. In the meantime the other 4 chemicals might have their targets after the IL-2 production signal. Taken all together, the three-step test would be simple, fast, and efficient to deter-mine whether or not the chemical has immunosuppressive effects.

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Functional Characteristics of C-terminal Lysine to Cysteine Mutant Form of CTLA-4Ig

  • Kim, Bongi;Shin, Jun-Seop;Park, Chung-Gyu
    • IMMUNE NETWORK
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    • 제13권1호
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    • pp.16-24
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    • 2013
  • CTLA-4Ig is regarded as an inhibitory agent of the T cell proliferation via blocking the costimulatory signal which is essential for full T cell activation. To improve applicability, we developed the CTLA-4Ig-CTKC in which the c-terminal lysine had been replaced by cysteine through single amino acid change. The single amino acid mutation of c-terminus of CTLA-4Ig was performed by PCR and was checked by in vitro transcription and translation. DNA construct of mutant form was transfected to Chinese hamster ovary (CHO) cells by electroporation. The purified proteins were confirmed by Western blot and B7-1 binding assay for their binding ability. The suppressive capacity of CTLA-4Ig-CTKC was evaluated by the mixed lymphocyte reaction (MLR) and in the allogeneic pancreatic islet transplantation model. CTLA-4Ig-CTKC maintained binding ability to B7-1 molecule and effectively inhibits T cell proliferation in MLR. In the murine allogeneic pancreatic islet transplantation, short-term treatment of CTLA-4Ig-CTKC prolonged the graft survival over 100 days. CTLA-4Ig-CTKC effectively inhibits immune response both in MLR and in allogeneic islet transplantation model, indicating that single amino acid mutation does not affect the inhibitory function of CTLA-4Ig. CTLA-4Ig-CTKC can be used in vehicle-mediated drug delivery system such as liposome conjugation.

골수생검 양성인 속립성 결핵의 고찰 (Clinical and Immunologic Features of Miliary Tuberculosis with Positive Bone Marrow Study)

  • 송광선;용석중;신계철;이원연;류정선
    • Tuberculosis and Respiratory Diseases
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    • 제43권1호
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    • pp.22-29
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    • 1996
  • 연구배경: 속립성 결핵환자에서 말초혈액의 변화는 골수생검상 결핵성 병변을 보인 군에서 더 많은 것으로 알려져 있고, 폐결핵보다 속립성 결핵에서 세포성 면역의 변화가 심한 것으로 연구되어지고 있다. 방법: 대상은 1990년에서 1994년 사이에 원주의과 대학부속 원주기독병원에 내원하여 속립성 결핵으로 진단받고 골수생검을 시행받은 환자 40예 였다. 이들을 골수생검상 결핵성 병변을 보인 양성군과 보이지 않은 음성군으로 나누어 임상상, 말초 혈액의 혈청 ADA, 수용성 인터루킨 2 수용체, 임파구 아형 분류를 시행하여 비교하였다. 결과: 1) 대상 환자의 평균연령은 39세로, 남녀는 23:17예 이었다. 2) 동반된 폐외 결핵으로는 결핵성 뇌막염이 9예, 결핵성 관절염이 6예, 결핵성 흉막염이 2예 있었다. 3) 골수검사상 60%(24/40)가 결핵성 병변을 보였다. 4) 말초혈액검사상 빈혈은 60%(24/40)가 있었으며 골수생검 양성군에서 11예 음성군에서 13예였고, 백혈구감소증은 12%(5/40)로 양성군에서 4예 음성군에서 1예였고, 혈소판 감소증은 10%(4/40)로 양성군이 3예 였다. 5) 혈청 ADA는 평균 83 U/L로 양성군에서 90 U/L, 음성군에서 70.6 U/L 이었다(p=0.23). 6) 혈청 가용성 interleukin 2 수용체 활성도는 평균 4,643 pmol/L 였으며 양성군에서 $6,840{\pm}7,446\;pmol/L$(n=10), 음성군 $1897{\pm}1663\;pmol/L$(n=8)으로 양성군에서 더 높았다(p=0.06). 7) 혈청내 T 임파구 아형분류에서 총 T 임파구는 평균 64%으로 양성군에서 $62{\pm}19%$(n=18), 음성군에서 $73{\pm}10%$ 였고(n=7)(p=0.2), $T_4/T_8$ ratio는 평균 $1.16{\pm}0.5$으로 양성군에서 $1.14{\pm}0.5$, 음성군에서 $1.18{\pm}0.5$였다(p=0.8). 8) 일부 환자(9예)에서 BAL의 T 임파구 아형분류을 시행하였으며 $T_4/T_8$ ratio는 $1.97{\pm}1.2$으로, 말초혈액소견과 비교하여 더 증가되어 있었다. 결론: 이상의 결과로 속립성 결핵의 골수생검 양성률은 60% 였으며, 골수생검상 결핵성 병변을 보인 군에서 말초혈액내 변화와 세포성 면역의 변화가 더 심한 경향을 보였다.

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사삼생맥산 추출물이 Balb/c mice의 면역활성에 미치는 효과 (Effect of Sasamsaengmaek-san Extract on Immunity Activity in Balb/c Mice)

  • 박채현;강재희;이현
    • 동의생리병리학회지
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    • 제36권6호
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    • pp.235-241
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    • 2022
  • The purpose of this study was to investigate the immune activation effect of Sasamsaengmaek-san (SSSMS) consisted of a mixture of Adenophora triphylla var. japonica, Liriope platyphylla, Panax ginseng C. A. Meyer and Schisandra chinensis. in Balb/c mice. Measuring alanine aminotransferase (ALT) and aspartic acid transaminase (AST) levels in Balb/c mice was performed to analyze the cytotoxicity. Cytokines (IFN-γ, IL-2, IL-12) which regulate the immune activation in Balb/c mice were measured by enzyme-linked immunosorbent assay (ELISA). Activated T lymphocytes in peripheral blood mononuclear cell (PBMC), spleen, lymph nodes were analyzed by flow cytometry using percentages. All tests were compared with red ginseng 100 ㎍/mL (RG 100), which is the most used for immune activity. As a result, cytokine activity was significantly increased at SSSMS 300 group. Activated T lymphocytes in PBMC, spleen, lymph nodes were significantly increased at SSSMS 300 group. These results suggest that there is a possibility of SSSMS activating an immune system by activating the cytokines, and it is confirmed that SSSMS also effective for generation and differentiation of T, B lymphocytes which activate the immune response.

항종양 면역반응 유도를 위한 수지상세포의 최적 활성화 조건 (The Optimal Activation State of Dendritic Cells for the Induction of Antitumor Immunity)

  • 남병혁;조월순;이기원;오수정;강은영;최유진;도은주;홍숙희;임영진;김기욱;정민호
    • 생명과학회지
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    • 제16권6호
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    • pp.904-910
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    • 2006
  • 수지상세포는 종양면역에서 필수적인 강력한 CTL 반응을 개시할 수 있는 유일한 세포이다 . 특히 외인성 종양항원에 대한 CTL 반응 유도는 활성화된 수지상세포의 IL-12 분비를 통한 CD4+ helper T세포의 cross-priming을 필요로 한다. 그러나 최근에 활성화된 수지상세포는 $Th_1$ 면역반응을 유도하지만 활성화 시간이 경과함에 따라 오히려 $Th_2$반응을 유도 할 수 있다. 따라서 본 연구에서는 OVA를 종양항원 모델로 설정하여 종양특이적인 CTL 반응을 형성하기 위한 최적의 수지상세포 활성화 조건을 조사하였다. 마우스 골수세포에 서 수지상세포로의 분화는 항원제시 기능을 위한 표면분자의 발현 측면에서 볼 때 배양 6일-7일 정도가 적합하였다. 수지상세포의 IL-12 생성능은 배양 6일 이상, OVA 항원 탑재 8시간 이상의 경우에 연이은 LPS 성숙자극으로 오히려 감소하는 경향을 보였다. 즉 배양 6일의 수지상세포에 OVA 항원 탑재를 8시간 수행한 경우(8-h DC)가 in vitro에서의 IL-12생성능, ex vivo에서의 세포내 $IFN-{\gamma}$를 발현하는 CD8+ T세포의 증가 및 OVA 특이적인 세포독성효과 등에서 가장 좋은 결과를 보였다. 또한 in vivo에서 종양 치료 및 예방효과에서도 8-h DC로 면역한 경우에 가장 우수한 종양형성 억제 효과와 생존기간 연장효과를 보였다. 현재 대부분의 수지상 세포를 이용한 항종양 백신에서 항원 탑재반응을 24시간 동안 수행하고 있으나, 본 실험의 결과로 볼 때, 8시간의 in vitro 항원 탑재가 보다 효과적인 종양특이적 CTL 반응과 항종양 면역반응을 유도함을 알 수 있다. 결론적으로 본 연구를 통하여 8시간 이상의 항원접촉은 수지상세포의 기능적 활성능력을 오히려 고갈시킬 수 있음을 제시한다.

Putative proinflammatory cytokine유전자의 발현양상과 수용체 분자의 cloing (GENE EXPRESSION CHARACTERISTICS OF PUTATIVE PROINFLAMMATORY CYTOKINES AND RECEPTOR MOLECULE CLONING)

  • 오귀옥;송요한;서영석;이동환;문대희;김형섭
    • Journal of Periodontal and Implant Science
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    • 제24권3호
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    • pp.472-482
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    • 1994
  • Cytokines expressed specifically in leukocytes subsets and in activated cells, which are involved in chemotaxis and activation of leukocytes, are recently defined as chemokines. Macrophage inflammatory $protein-1{\alpha}(MIP-1{\alpha})$ and $MIP-1{\beta}$ are members of C-C chemokine subfamily which produces wide immunomodulatory, proinflammatory, and hematopoietic modulatory actions. We have studied their gene expression by using Northern blot analysis in various blood cells such as cytolytic T lymphocyte(CTL), helper T lymphocyte(HTL), macrophage, and B lymphocyte. Resting CTL line CTLL-R8 expressed $MIP-1{\alpha}$ mRNA which was downregulated by ConA stimulation. Both of resting and ConA stimulated HTL line Hut78 and Jurkat did not express $MIP-1{\alpha}$ mRNA. There was detectable $MIP-1{\alpha}$ transcript in HTL hybridoma 2B4.11 which was a little upstimulated by ConA stimulation. B cell line 230, and macrophage cell line RAW264.7 and WR19M.1 showed distinct $MIP-1{\alpha}$ message which were induced after LPS stimulation. Expression pattern of $MIP-1{\beta}$ in all cell lines or cell were almost identical to that of $MIP-1{\alpha}$. Also strategies employed to identify and characterize the biological functions was preceded by receptor cloning to trace the shorcut to the final goal of cytokine research. For the cloning of $MIP-1{\alpha}$ receptor(R), we used synthetic oligonucleotides of transmembrane(T) conserved sequences of already cloned human(h) IL-8-R, and performed reverse transcription-polymerase chain reaction(RT-PCR) amplification using murine(m) macrophage cell line mRNA. Among 5RT-PCR products, we isolated a homologous cDNA with hIL-8-R which were shown to be putative mIL-8-R cDNA.

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Heterogeneity of Human γδ T Cells and Their Role in Cancer Immunity

  • Hye Won Lee;Yun Shin Chung;Tae Jin Kim
    • IMMUNE NETWORK
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    • 제20권1호
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    • pp.5.1-5.15
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    • 2020
  • The γδ T cells are unconventional lymphocytes that function in both innate and adaptive immune responses against various intracellular and infectious stresses. The γδ T cells can be exploited as cancer-killing effector cells since γδ TCRs recognize MHC-like molecules and growth factor receptors that are upregulated in cancer cells, and γδ T cells can differentiate into cytotoxic effector cells. However, γδ T cells may also promote tumor progression by secreting IL-17 or other cytokines. Therefore, it is essential to understand how the differentiation and homeostasis of γδ T cells are regulated and whether distinct γδ T cell subsets have different functions. Human γδ T cells are classified into Vδ2 and non-Vδ2 γδ T cells. The majority of Vδ2 γδ T cells are Vγ9δ2 T cells that recognize pyrophosphorylated isoprenoids generated by the dysregulated mevalonate pathway. In contrast, Vδ1 T cells expand from initially diverse TCR repertoire in patients with infectious diseases and cancers. The ligands of Vδ1 T cells are diverse and include the growth factor receptors such as endothelial protein C receptor. Both Vδ1 and Vδ2 γδ T cells are implicated to have immunotherapeutic potentials for cancers, but the detailed elucidation of the distinct characteristics of 2 populations will be required to enhance the immunotherapeutic potential of γδ T cells. Here, we summarize recent progress regarding cancer immunology of human γδ T cells, including their development, heterogeneity, and plasticity, the putative mechanisms underlying ligand recognition and activation, and their dual effects on tumor progression in the tumor microenvironment.

A Novel Therapeutic Effect of a New Variant of CTLA4-Ig with Four Antennas That Are Terminally Capped with Sialic Acid in the CTLA4 Region

  • Piao, Yongwei;Yun, So Yoon;Kim, Hee Soo;Park, Bo Kyung;Ha, Hae Chan;Fu, Zhicheng;Jang, Ji Min;Back, Moon Jung;Shin, In Chul;Won, Jong Hoon;Kim, Dae Kyong
    • Biomolecules & Therapeutics
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    • 제30권6호
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    • pp.529-539
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    • 2022
  • Rheumatoid arthritis (RA) is a multifactorial immune-mediated disease, the pathogenesis of which involves different cell types. T-cell activation plays an important role in RA. Therefore, inhibiting T-cell activation is one of the current therapeutic strategies. Cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig), also known as abatacept, reduces cytokine secretion by inhibiting T-cell activation. To achieve a homeostatic therapeutic effect, CTLA4-Ig has to be administered repeatedly over several weeks, which limits its applicability in RA treatment. To overcome this limitation, we increased the number of sialic acid-capped antennas by genetically engineering the CTLA4 region to increase the therapeutic effect of CTLA4-Ig. N-acetylglucosaminyltransferase (GnT) and α2,6-sialyltransferase (α2,6-ST) were co-overexpressed in Chinese hamster ovary (CHO) cells to generate a highly sialylated CTLA4-Ig fusion protein, named ST6. The therapeutic and immunogenic effects of ST6 and CTLA4-Ig were compared. ST6 dose-dependently decreased paw edema in a mouse model of collagen-induced arthritis and reduced cytokine levels in a co-culture cell assay in a similar manner to CTLA4-Ig. ST6- and CTLA4-Ig-induced T cell-derived cytokines were examined in CD4 T cells isolated from peripheral blood mononuclear cells after cell killing through irradiation followed by flow- and magnetic-bead-assisted separation. Interestingly, compared to CTLA4-Ig, ST6 was substantially less immunogenic and more stable and durable. Our data suggest that ST6 can serve as a novel, less immunogenic therapeutic strategy for patients with RA.

Huh7.5 간암 세포주의 HCV 항원제시에 의한 HCV 특이 T 림프구의 활성에 관한 연구 (The Activation of HCV-specific CD8 T Cells by HCV Peptide Pulsed Huh7.5 Cells)

  • 조효선
    • 미생물학회지
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    • 제47권4호
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    • pp.342-347
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    • 2011
  • 인체의 바이러스 감염 방어기전에서 T 림프구는 중요한 역할을 한다. 하지만, 만성 C형 간염 바이러스의 일차적 복제장소인 간염 환자의 간에서 분리된 HCV 특이 T 림프구는 심각한 기능결핍을 보인다. 이러한 T 림프구 기능결핍의 이유로는 PD-1, CTLA-4 등 면역억제 물질의 발현, 또는 간에서 특이적으로 유도되는 면역내성(immune tolerance)이 있으나, 간세포(hepatocytes)와 HCV 특이 T 림프구의 상호작용에 대해서는 명확하게 확립되어 있지 않다. 따라서 본 연구에서는 HLA(human leukocyte antigen) A2+ 간암세포주(human hepatoma cell line; huh7.5)가 항원제시(antigen presentation)를 통해 효과적으로 HCV 특이 T 림프구를 활성화시키며 간암세포주(huh7.5) 표면의 PD-L (program death ligand) 1 발현은 T림프구의 활성을 감소시켜 면역조절의 가능성이 있음을 시사하였다. 또한, HCV 특이 tetramer 반응은 T 림프구의 과도한 활성으로 자기사멸(apoptosis)의 경로에 있음을 caspase 3 활성으로 확인하였고, 역시 PD-L1의 발현이 T 림프구를 자기사멸(apoptosis)로부터 구제하여 caspase 3 활성이 감소하는 것을 확인하였다. 이는 PD-L1과 간성(liver) T 림프구 표면의 PD-1 결합이 T 림프구의 자기사멸을 막고, 또한 그 기능을 회복시켜 만성 C형 간염 치료에 응용될 수 있음을 시사한다.