• BMB Reports
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• 제47권2호
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• pp.115-120
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• 2014

In this study, we show that Mycobacterium avium subsp. paratuberculosis MAP1305 induces the maturation of bone marrow-derived dendritic cells (BMDCs), a representative antigen presenting cell (APC). MAP1305 protein induces DC maturation and the production of pro-inflammatory cytokines (Interleukin (IL)-6), tumor necrosis factor (TNF)-${\alpha}$, and IL-$1{\beta}$) through Toll like receptor-4 (TLR-4) signaling by directly binding with TLR4. MAP1305 activates the phosphorylation of MAPKs, such as ERK, p38MAPK, and JNK, which is essential for DC maturation. Furthermore, MAP1305-treated DCs transform naive T cells to polarized $CD4^+$ and $CD8^+$ T cells, thus indicating a key role for this protein in the Th1 polarization of the resulting immune response. Taken together, M. avium subsp. paratuberculosis MAP1305 is important for the regulation of innate immune response through DC-mediated proliferation of $CD4^+$ and $CD8^+$ T cells.

• Animal cells and systems
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• 제16권3호
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• pp.215-223
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• 2012

Recently it has been reported that immunization with heat-killed tumor cells (HK vaccine) induces anti-tumor immune responses in mice. To investigate how HKvaccine elicits anti-tumor specific adaptive immunity, we examined the effect of HK vaccination on innate immune cells such as dendritic cells (DCs), which are essential for the generation of adaptive immunity. Upon stimulation with HK vaccine, DCs matured to promote not only the upregulation of co-stimulatory molecules but also secretion of cytokine IL12. Furthermore, HK vaccine-treated DCs migrated more efficiently to draining lymph nodes compared with untreated ones. Taken together, HK vaccine can be useful as an adjuvant to activate DCs for anti-tumor immune responses.

• Journal of Gastric Cancer
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• 제5권3호
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• pp.206-212
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• 2005

목적: 신생혈관형성은 암의 증식, 침습, 전이에 있어 중요한 과정이며 위선암에서 대식세포, 비만세포는 혈관내피세포성장인자를 통한 신생혈관형성 작용을 보이고 가지세포는 혈관내피세포성장인자에 의해 기능이 억제된다. 이들 세포의 조직 침습이 조직병리 및 임상예후와 어떤 상관관계를 가지는지 알아보고자 한다. 대상 및 방법: 1999년 1월부터 2002년 12월까지 진행성 위암으로 위절제술을 받은 환자 중 79명을 대상으로 하여 파라핀 포매 조직을 이용하여 대식세포, 비만세포, 가지세포 및 미세혈관에 대한 면역조직화학 염색을 실시하고, 이들의 발현과 임상병기 및 생존율에 대한 분석을 실시하였다. 결과: 대식세포의 수는 분화도가 낮을수록, 조직침습이 깊을수록, 림프절전이가 많을수록 유의하게 감소하였으나(P<0.05), 미세혈관 밀도 및 생존기간의 차이는 보이지 않았다. 비만세포와 가지세포의 침윤정도는 조직병리 및 생존율과의 연관성을 보이지 않았다. 결론: 종양연관성 대식세포가 위암환자에 있어 예후인자로 가치를 가질 수 있을 것 인지와 대식세포의 침습부위에 따른 임상적 관련성에 대해 좀 더 세부적인 연구가 필요할 것으로 사료된다.

• IMMUNE NETWORK
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• 제8권4호
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• pp.137-142
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• 2008

Background: CD11c, also known as integrin alpha x, is one of the optimum markers of dendritic cells. However, the regulation of the CD11c expression in mouse has not been identified yet. In this study, in order to analyze the regulation of CD11c expression, the promoter of CD11c was cloned and characterized. Methods: To identify the promoter portion, various sizes of what are considered to be CD11c promoter fragments was amplified by polymerase chain reaction (PCR), using mouse genomic DNA as a template. After sequence was obtained, these fragments were transfected into various cell lines including mouse dendritic cell lines such as JAWSII and DC2.4 and L929 as control cell line.. The promoter activity of three promoter fragments was measured and compared by luciferase activity in the transfected cells. Results: Three clones with size of 1kb, 3kb and 6kb were obtained from mouse genomic DNA. Flow cytometry analysis of JAWSII cells revealed that 52% of the cells expressed CD11c, which was confirmed by RT-PCR analysis. On the contrary, L929 and DC 2.4 cells did not express CD11c. The CD11c+ JAWSII cells were enriched from 52% to 90% with cell sorter. The comparative luciferase activity analyisis demonstrated that the region responsible for tissue specific expression was contained within -3 kb and the clone with size of 3 kb particularly showed higher luciferase activity than 6 kb and 1 kb clones. Conclusion: The CD11c promoter region containing the region responsible for tissue specificity was successfully cloned and -3 kb region showed the highest activity.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.611-616
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• 2014

Objectives: Dendritic cell (DC)-based tumor immunotherapy needs an immunogenic tumor associated antigen (TAA) and an effective approach for its presentation to lymphocytes. In this study we explored whether transduction of DCs with lentiviruses (LVs) expressing the human interleukin-12 gene could stimulate antigen-specific cytotoxic T cells (CTLs) against human lung cancer cells in vitro. Methods: Peripheral blood monocyte-derived DCs were transduced with a lentiviral vector encoding human IL-12 gene (LV-12). The anticipated target of the human IL-12 gene was detected by RT-PCR. The concentration of IL-12 in the culture supernatant of DCs was measured by ELISA.Transduction efficiencies and CD83 phenotypes of DCs were assessed by flow cytometry. DCs were pulsed with tumor antigen of lung cancer cells (DC+Ag) and transduced with LV-12 (DC-LV-12+Ag). Stimulation of T lymphocyte proliferation by DCs and activation of cytotoxic T-lymphocytes (CTL) stimulated by LV-12 transduced DCs pulsed with tumor antigen against A549 lung cancer cells were assessed with methyl thiazolyltetrazolium (MTT). Results: A recombinant lentivirus expressing the IL-12 gene was successfully constructed. DC transduced with LV-12 produced higher levels of IL-12 and expressed higher levels of CD83 than non-transduced. The DC modified by interleukin -12 gene and pulsed with tumor antigen demonstrated good stimulation of lymphocyte proliferation, induction of antigen-specific cytotoxic T lymphocytes and antitumor effects. Conclusions: Dendritic cells transduced with a lentivirus-mediated interleukin-12 gene have an enhanced ability to kill lung cancer cells through promoting T lymphocyte proliferation and cytotoxicity.

• IMMUNE NETWORK
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• 제13권5호
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• pp.218-221
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• 2013

CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although ${\alpha}$-galactosylceramide (${\alpha}$-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-${\gamma}$ by NKT cells, concomitant with a decreased level of IL-4, in the circumstance of co-culture of DCs and B Cells. Remarkably, the response promoted by B cells was dependent on CD1d expression of B cells.

• IMMUNE NETWORK
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• 제15권3호
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• pp.111-120
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• 2015

Dendritic cells (DCs) play a significant role in establishing self-tolerance through their ability to present self-antigens to developing T cells in the thymus. DCs are predominantly localized in the medullary region of thymus and present a broad range of self-antigens, which include tissue-restricted antigens expressed and transferred from medullary thymic epithelial cells, circulating antigens directly captured by thymic DCs through coticomedullary junction blood vessels, and peripheral tissue antigens captured and transported by peripheral tissue DCs homing to the thymus. When antigen-presenting DCs make a high affinity interaction with antigen-specific thymocytes, this interaction drives the interacting thymocytes to death, a process often referred to as negative selection, which fundamentally blocks the self-reactive thymocytes from differentiating into mature T cells. Alternatively, the interacting thymocytes differentiate into the regulatory T (Treg) cells, a distinct T cell subset with potent immune suppressive activities. The specific mechanisms by which thymic DCs differentiate Treg cells have been proposed by several laboratories. Here, we review the literatures that elucidate the contribution of thymic DCs to negative selection and Treg cell differentiation, and discusses its potential mechanisms and future directions.

• IMMUNE NETWORK
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• 제11권6호
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• pp.364-367
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• 2011

Background: Prostaglandins (PGs) play pathogenic and protective roles in inflammatory diseases. The novel concept of PGs as immune modulators is being documented by several investigators. By establishing an in vitro experimental model containing human follicular dendritic cell-like cells, HK cells, we reported that HK cells produce prostaglandin $E_2$ ($PGE_2$) and prostaglandin $I_2$ ($PGI_2$) and that these PGs regulate biological functions of T and B cells. Methods: To investigate the respective contribution of cyclooxygenase-1 (COX-1) and COX-2 to $PGE_2$ and $PGI_2$ production in HK cells, we performed siRNA technology to knock down COX enzymes and examined the effect on PG production. Results: Both $PGE_2$ and $PGI_2$ productions were almost completely inhibited by the depletion of COX-2. In contrast, COX-1 knockdown did not significantly affect PG production induced by lipopolysaccharide (LPS). Conclusion: The current results suggest that mPGES-1 and PGIS are coupled with COX-2 but not with COX-1 in human follicular dendritic cell (FDC) and may help understand the potential effects of selective COX inhibitors on the humoral immunity.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1996년도 한국생물과학협회 국제학술대회
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• pp.138.1-138
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• 1996

No Abstract, See Full Text

• Tuberculosis and Respiratory Diseases
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• 제60권5호
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• pp.523-531
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• 2006

연구배경: 결핵성 경부 림프절염은 우리나라에서 폐결핵만큼 빈도가 높은 질환이다. 이 질병에서 수지상돌기세포는 초기의 항원 제시역할을 하고 있다. 그러나 림프절염의 임상 양상과 관련된 항원제시세포의 역할은 아직 명확하게 밝혀져 있지 않은 상태이다. 경부 림프절의 수지상 돌기세포의 침윤과 임상양상과의 연관성을 알아보기 위해 본 연구를 시행하였다. 방 법: 환자들의 입원기록 및 방사선사진을 바탕으로 후향적으로 고찰하였다. 72례의 조직표본을 대상으로 항산균도말염색을 다시 시행하였고, 수지상돌기세포의 단클론항체로 S-100b를 이용하여 면역조직 화학염색을 시행한 후, 각각 결핵성 육아종안의 수지상돌기세포의 수를 세어 비교분석하였다. 결 과: 결핵성 경부 림프절염이 있는 환자들의 30%가 폐결핵의 과거력이 있거나 현재 폐결핵을 앓고 있는 상태이었고 21%의 환자에서 항산균도말염색양성을 보였다. 이들 한 육아종안에 침윤된 수지상돌기세포의 수는 평균 $113.0{\pm}7.0$개이었다. 육아종내 수지상돌기세포의 침윤수가 증가됨에 따라 발열과 기침의 빈도는 감소하였고 항산균도말염색상에서 결핵균의 수가 더 감소하는 결과를 보였으며, 다중로짓회귀분석을 보면, 수지상돌기세포의 침윤은 특징적으로 발열에 기여하여하는 것으로 나타났다. 결 론: 수지상돌기세포가 결핵성 경부 림프절염에서 발열과 기침 등의 전신증상을 줄이고, 결핵균의 침윤정도를 감소시키는 것으로 확인되었고, 이는 수지상돌기세포가 Mycobacterium tuberculosis의 감염을 조절하고 이와 함께 면역반응도 조절하여, 결핵성 경부 림프절염에서의 임상양상을 결정하는 것으로 생각된다.