• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.62-63
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• 2003

The commitment of T helper (Th) cells to Thl or Th2 cells is of crucial importance with respective to susceptibility or resistance to particular infections, or to autoimmune diseases and allergic diseases. The nature of Thl or Th2 polarizing signals is not yet fully understood. However, the cytokines that are present in the environment of the $CD4^{+}$ T cell at the time it encounters the antigen significantly regulate the differentiation of Th cells into either Thl or Th2 subsets. (omitted)

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.171-176
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• 2012

HaCaT cells are the immortalized human keratinocytes and have been extensively used to study the epidermal homeostasis and its pathophysiology. T helper cells play a role in various chronic dermatological conditions and they can affect skin barrier homeostasis. To evaluate whether HaCaT cells can be used as a model cell system to study abnormal skin barrier development in various dermatologic diseases, we analyzed the gene expression profile of epidermal differentiation markers of HaCaT cells in response to major T helper (Th) cell cytokines, such as $IFN{\gamma}$, IL-4, IL-17A and IL-22. The gene transcriptional profile of cornified envelope-associated proteins, such as filaggrin, loricrin, involucrin and keratin 10 (KRT10), in HaCaT cells was generally different from that in normal human keratinocytes (NHKs). This suggests that HaCaT cells have a limitation as a model system to study the pathophysiological mechanism associated with the Th cell cytokine-dependent changes in cornified envelope-associated proteins which are essential for normal skin barrier development. In contrast, the gene transcription profile change of human ${\beta}2$-defensin (HBD2) in response to $IFN{\gamma}$, IL-4 or IL-17A in HaCaT cells was consistent with the expression pattern of NHKs. $IFN{\gamma}$ also up-regulated transglutaminase 2 (TGM2) gene transcription in both HaCaT cells and NHKs. As an alternative cell culture system for NHKs, HaCaT cells can be used to study molecular mechanisms associated with abnormal HBD2 and TGM2 expression in response to $IFN{\gamma}$, IL-4 or IL-17A.

• 한국가금학회지
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• 제28권3호
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• pp.231-237
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• 2001

육계를 13주간 사육하면서 5주령부터 시험사료를 급여한 후 세포표면항원의 발현에 미치는 영향을 측정하기 위하여, 아마종실과 항산화제를 첨가하지 않은 대조구($T_{1}$ ), 아마종실만을 첨가한 사료($T_{2}$ ), 아마종실과 u-toco-pherol을 첨가한 사료($T_{3}$ ), 아마종실에 u-tocopherol과 셀레늄을 첨가한 사료($T_{4}$ )를 육계에 급여한 바 면역반응에 미치는 영향은 다음과 같았다. 1차 면역에 관여하는 monocyte 군은 시험사료의 급여기간이 증가할수록 $T_{1}$ 에 비하여 $T_{2}$ , $T_{3}$ , $T_{4}$ 구에서 유의적으로 증가하는 경향을 보였는데 그중 $T_{2}$ 구와 $T_{3}$ 구에서 많이 증가되었다. B세포는 시험사료의 급여기간보다는 급여사료에 따라 증가하였는데,$T_{2} , $T_{3}, $T_{4}$ 구는 $T_{1}$ 구에 비하여 2배 이상 증가하였다. CD4 양성반응(T helper cell)과 CD8 양성 세포(T $cytotoxic^pressor cell)는 $T_{2}$ , $T_{3}$ ,$T_{4}$ 구는 $T_{1}$ 구보다 증가하였으나 사료에 따라 일정한 차이는 없었다. MHC classII는 시험사료의 종류나 급여 기간에 따라 차이는 없었다.었다.

• Clinical and Experimental Reproductive Medicine
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• 제37권3호
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• pp.231-237
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• 2010

목 적: 반복적 유산 또는 반복적 착상실패 환자의 T 림프구의 Th1 면역반응 정도를 알아보고, T 림프구 활성 정도를 분석하고자 하였다. 연구방법: 반복적 유산 및 반복적 착상실패를 경험한 37명의 환자를 연구군으로 설정하고, 유산이나 불임의 병력이 없이 정상분만의 경력이 있는 11명의 가임 여성을 대조군으로 모집하였다. 유세포분석기를 이용하여, 이들의 말초혈액 중 T helper 세포 내 TNF-$\alpha$와 INF-$\gamma$ 및 IL-10의 발현도를 측정하고 Th1/Th2 세포 비율 (TNF-$\alpha$/IL-10 및 INF-$gamma$/IL-10 발현도)을 계산하여 Th1 면역반응의 우세 정도 및 T 림프구의 활성도를 분석하였으며, 활성 표지자인 CD154와 CD69 발현 정도를 비교하였다. 결 과: 연구군의 평균연령은 $35.3{\pm}4.3$세였으며, 이들에서 T helper cell 내 TNF-$\alpha$/IL-10의 발현 비율이 대조군에 비해 유의하게 높았고 ($42.1{\pm}2.3$ vs. $28.7{\pm}2.7$, p=0.002), CD154와 CD69의 발현율 또한 대조군에 비해 전반적으로 높았다. CD154의 경우, T helper cell ($1.7{\pm}0.5$ vs. $0.3{\pm}0.2$, p=0.038)과 T suppressor cell ($0.6{\pm}0.2$ vs. $0.1{\pm}0.0$, p=0.024) 모두에서 유의하게 높은 발현을 보인 반면, CD69의 경우, 전체 T 림프구 ($5.6{\pm}1.9$ vs. $1.3{\pm}5.4$, p=0.046)와 T suppressor cell ($4.8{\pm}1.3$ vs. $1.8{\pm}0.2$, p=0.035)에서 통계적으로 높은 발현을 확인할 수 있었다. 결 론: 반복적 유산 및 반복적 착상실패를 보이는 여성에서 T 림프구의 활성도와 Th1 면역반응이 증가하였으며 이는, 이들 여성에서 활성화된 T 림프구가 Th1 면역반응을 유도하여 초기 임신의 유지와 착상에 좋지 않은 영향을 미치기 때문으로 생각된다.

• IMMUNE NETWORK
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• 제16권1호
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• pp.13-25
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• 2016

Dendritic cells (DCs) are considered to play major roles during the induction of T cell immune responses as well as the maintenance of T cell tolerance. Naive CD4⁺ T cells have been shown to respond with high plasticity to signals inducing their polarization into effector/helper or regulatory T cells. Data obtained from in vitro generated bone-marrow (BM)-derived DCs as well as genetic mouse models revealed an important but not exclusive role of DCs in shaping CD4⁺ T cell responses. Besides the specialization of some conventional DC subsets for the induction of polarized immunity, also the maturation stage, activation of specialized transcription factors and the cytokine production of DCs have major impact on CD4⁺ T cells. Since in vitro generated BM-DCs show a high diversity to shape CD4⁺ T cells and their high similarity to monocyte-derived DCs in vivo, this review reports data mainly on BM-DCs in this process and only touches the roles of transcription factors or of DC subsets, which have been discussed elsewhere. Here, recent findings on 1) the conversion of naive into anergic and further into Foxp3^- regulatory T cells (Treg) by immature DCs, 2) the role of RelB in steady state migratory DCs (ssmDCs) for conversion of naive T cells into Foxp3⁺ Treg, 3) the DC maturation signature for polarized Th2 cell induction and 4) the DC source of IL-12 for Th1 induction are discussed.

• IMMUNE NETWORK
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• 제23권1호
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• pp.4.1-4.15
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• 2023

Th cells, which orchestrate immune responses to various pathogens, differentiate from naive CD4 T cells into several subsets that stimulate and regulate immune responses against various types of pathogens, as well as a variety of immune-related diseases. Decades of research have revealed that the fate decision processes are controlled by cytokines, cytokine receptor signaling, and master transcription factors that drive the differentiation programs. Since the Th1 and Th2 paradigm was proposed, many subsets have been added to the list. In this review, I will summarize these events, including the fate decision processes, subset functions, transcriptional regulation, metabolic regulation, and plasticity and heterogeneity. I will also introduce current topics of interest.

• 한양메디칼리뷰
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• 제33권1호
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• pp.10-16
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• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• Journal of Periodontal and Implant Science
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• 제30권3호
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• pp.675-687
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• 2000

Multiple periodontal pathogens sequentially colonize the subgingival niche during the conversion from gingivitis to destructive periodontal disease. An animal model of sequential immunization with key periodontal pathogens has been developed to determine whether T and B lymppocyte effector functions are skewed and fail to protect the host from pathogenic challenge. The present study was performed to evaluate immunomodulatory effect of exposure to Fusobacterium nucleatum(F. nucleatum) prior to Porphyromonas gingivalis(P. gingi - valis). Group 1(control) mice were immunized with phosphate-buffered saline, Group 2 were immunized with F. nucleatum prior to P. gingivalis, while Group 3 were immunized P. gingivalis alone. All the T cell clones derived from Group 2 demonstrated type 2 helper T cell clone(Th2 subsets), while those from Group 3 mice demonstrated Th1 subsets. Exposure of mice to F . nucleatum prior to P. gingivalis interfered with opsonophagocytosis function of sera against P. gingivalis. In adoptive T cell transfer experiments, in vivo protective capacity type 2 helper T cell clones(Th2) from Group 2 was significantly lower than type 1 helper T cell clones(Th1) from Group 3 against the lethal dose infection of P. gingivalis. Western blot analysis indicated the different pattern of recognition of P .gingivalis fimbrial proteins between sera from Group 2 and Group 3. In conclusion, these study suggest that colonization of the subgingival niche by F .nucleatum prior to the periodontal pathogen, P. gingivalis, modulates the host immune responses to P. gingivalis at humoral, cellular and molecular levels.

• 동의생리병리학회지
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• 제18권4호
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• pp.1021-1027
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• 2004

Panax ginseng has been used as a typical tonic medicine in Asian countries, such as Korea, China, and Japan. It has been reported that ginsenoside Rg1 in Panax ginseng increases the proportion of T helper cells in the whole T cells and promotes IL-2 gene expression in murine splenocytes. These studies imply that ginsenoside Rg1 increases the immune activity of CD4+ T cell, however the exact mechanism of ginsenoside Rg1 on helper T cell remains to be verified. The present study tried to elucidate the direct effect of Rg1 on helper T cell s activities and its Th1/Th2 lineage development. The results demonstrated that ginsenoside Rg1 had not mitogenic effects on the unstimulated CD4+ T cell, but augmented CD4+ T cell proliferation upon activating with anti-CD3/anti-CD28 antibodies in a dose dependent manner. Rg1 also enhanced the expression of cell surface protein CD69 on CD4+ T cell. In Th0 condition, ginsenoside Rg1 increases the expression of IL-2 mRNA, and enhances the expression of IL-4 mRNA on CD4+ T cells, suggesting Rg1 prefer to induce Th2 lineage development. In addition, ginsenoside Rg1 increases IL-4 secreting CD4+ T cell under Th2 skewed condition, while decreases IFN-γ secreting cell in Th1 polarizing condition. Thus, Rg1 enhances Th2 lineage development from naive CD4+ T cell both by increasing Th2 specific cytokine secretion and by repressing Th1 specific cytokine production. Therefore, these results suggest that ginsenoside Rg1 might be desirable agent for enhancing CD4+ T cell's activity, as well as the correction of Th1 dominant pathological disorders.

• IMMUNE NETWORK
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• 제23권1호
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• pp.5.1-5.28
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• 2023

Th cell lineage determination and functional specialization are tightly linked to the activation of lineage-determining transcription factors (TFs) that bind cis-regulatory elements. These lineage-determining TFs act in concert with multiple layers of transcriptional regulators to alter the epigenetic landscape, including DNA methylation, histone modification and threedimensional chromosome architecture, in order to facilitate the specific Th gene expression programs that allow for phenotypic diversification. Accumulating evidence indicates that Th cell differentiation is not as rigid as classically held; rather, extensive phenotypic plasticity is an inherent feature of T cell lineages. Recent studies have begun to uncover the epigenetic programs that mechanistically govern T cell subset specification and immunological memory. Advances in next generation sequencing technologies have allowed global transcriptomic and epigenomic interrogation of CD4+ Th cells that extends previous findings focusing on individual loci. In this review, we provide an overview of recent genome-wide insights into the transcriptional and epigenetic regulation of CD4+ T cell-mediated adaptive immunity and discuss the implications for disease as well as immunotherapies.