• Genomics & Informatics
• /
• 제21권2호
• /
• pp.18.1-18.11
• /
• 2023

Immunologists have activated T cells in vitro using various stimulation methods, including phorbol myristate acetate (PMA)/ionomycin and αCD3/αCD28 agonistic antibodies. PMA stimulates protein kinase C, activating nuclear factor-κB, and ionomycin increases intracellular calcium levels, resulting in activation of nuclear factor of activated T cell. In contrast, αCD3/αCD28 agonistic antibodies activate T cells through ZAP-70, which phosphorylates linker for activation of T cell and SH2-domain-containing leukocyte protein of 76 kD. However, despite the use of these two different in vitro T cell activation methods for decades, the differential effects of chemical-based and antibody-based activation of primary human T cells have not yet been comprehensively described. Using single-cell RNA sequencing (scRNA-seq) technologies to analyze gene expression unbiasedly at the single-cell level, we compared the transcriptomic profiles of the non-physiological and physiological activation methods on human peripheral blood mononuclear cell-derived T cells from four independent donors. Remarkable transcriptomic differences in the expression of cytokines and their respective receptors were identified. We also identified activated CD4 T cell subsets (CD55⁺) enriched specifically by PMA/ionomycin activation. We believe this activated human T cell transcriptome atlas derived from two different activation methods will enhance our understanding, highlight the optimal use of these two in vitro T cell activation assays, and be applied as a reference standard when analyzing activated specific disease-originated T cells through scRNA-seq.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제18권1호
• /
• pp.153-163
• /
• 1996

Macrophage inflammatory protein $(MIP)-1{\alpha}$ is a cytokine which produces wide range of bioactivities such as proinflammatory, immunomodulatory, and hematopoietic modulatory actions. To determine whether $MIP-1{\alpha}$ acts as a negative regulator on the functions of lymphocyte, $[^3H]$-thymidine incorporation test and flow cytometric analysis were performed by using human tonsil T cell, human peripheral blood T cell, and murine cytolytic T lymphocyte (CTL) line CTLL-2, The results were as follow. 1. When human tonsil T lymphocytes were stimulated with anti-CD3 monoclonal antibody (mAb), rate of T cell proliferation was about four times increased. 200ng/ml of $MIP-1{\alpha}$ inhibited anti-CD3 mAb-mediated T cell growth as much as 60% (P<0.05). 2. The suppression of human peripheral T cell proliferation produced by $MIP-1{\alpha}$ was dramatic, but variable among T cells derived from different individuals $(40%{\sim}90%)$. 3. $MIP-1{\alpha}$inhibited the proliferation of murine CTL line CTLL-2 as much as 75%(P<0.001). 4. When the $MIP-1{\alpha}$ was added to human peripheral T cell, cell proporation of $CD4^+$ helper T cell and $CD8^+$ CTL were not noticeably affected. The expression level of CD4, not of Cd8, however, was down regulated by $MIP-1{\alpha}$ treatment $(27%{\sim}82%)$.

• Archives of Pharmacal Research
• /
• 제27권6호
• /
• pp.640-645
• /
• 2004

Histone deacetylase inhibitors are new class of chemotherapeutic drugs able to induce tumor cell apoptosis and／or cell cycle arrest. Trichostatin A, an antifungal antibiotic, and HC-toxin are potent and specific inhibitors of histone deacetylase activity. In this study, we have examined the antiproliferative activities of trichostatin A and HC-toxin in estrogen receptor positive human breast cancer, T47D cells. Both trichostatin A and HC-toxin showed potent antiprolifer-ative efficacy and cell cycle arrest at $G_2/M$ in T47D human breast cancer cells in a dose-dependent manner. Trichostatin A caused potent apoptosis of T47D human breast cancer cells and trichostatin A-induced apoptosis might be involved in an increase of caspase-3／7 activity. HC-toxin evoked apoptosis of T47D cells and HC-toxin induced apoptosis might not be medi-ated through direct increase in caspase-3/7 activity. We have identified potent activities of anti-proliferation, apoptosis, and cell cycle arrest of trichostatin A and HC-toxin in estrogen receptor positive human breast cancer cell line T47D.

• BMB Reports
• /
• 제44권8호
• /
• pp.512-516
• /
• 2011

Establishment of immortalized human dermal papilla cells (DPCs) retaining the characteristics of DPCs would be a great help for hair researchers. We recently established a simian virus 40T (SV40T)-transformed human DP cell line (SV40TDPC). However, the cell line senesced around passage 25 and ceased proliferation. In this study, we introduced the human telomerase reverse transcriptase (hTERT) gene into SV40T-DPC and established an immortalized human DP cell line. The cell line, SV40T-hTERT-DPC, did not induce tumors when inoculated into nude mice. SV40T-hTERT-DPC maintained morphology of early passage DPCs, expressed markers of DPCs, and retained responses to Wnt/${\beta}$-catenin and bone morphogenic protein (BMP) signaling pathways known to be required for hair-inducing activity of DPCs. The data strongly suggest that SV40T-hTERT-DPC retains many characteristics of human DPCs in vivo without malignant transformation.

• Molecules and Cells
• /
• 제40권1호
• /
• pp.37-44
• /
• 2017

PDK1 is essential for T cell receptor (TCR)-mediated activation of $NF-{\kappa}B$, and PDK1-induced phosphorylation of $PKC{\theta}$ is important for TCR-induced $NF-{\kappa}B$ activation. However, inverse regulation of PDK1 by $PKC{\theta}$ during T cell activation has not been investigated. In this study, we found that $PKC{\theta}$ is involved in human PDK1 phosphorylation and that its kinase activity is crucial for human PDK1 phosphorylation. Mass spectrometry analysis of wild-type $PKC{\theta}$ or of kinase-inactive form of $PKC{\theta}$ revealed that $PKC{\theta}$ induced phosphorylation of human PDK1 at Ser-64. This $PKC{\theta}$-induced PDK1 phosphorylation positively regulated T cell activation and TCR-induced $NF-{\kappa}B$ activation. Moreover, phosphorylation of human PDK1 at Ser-64 increased the stability of human PDK1 protein. These results suggest that Ser-64 is an important phosphorylation site that is part of a positive feedback loop for human PDK1-$PKC{\theta}$-mediated T cell activation.

• IMMUNE NETWORK
• /
• 제3권4호
• /
• pp.302-309
• /
• 2003

Background: CTLA4 (CD152), which is expressed on the surface of T cells following activation, has a much higher affinity for B7 molecules comparing to CD28, and is a negative regulator of T cell activation. In contrast to stimulating and agonistic capabilities of monoclonal antibodies specific to CTLA-4, CTLA4Ig fusion protein appears to act as CD28 antagonist and inhibits in vitro and in vivo T cell priming in variety of immunological conditions. We've set out to confirm whether inhibition of the CD28-B7 costimulatory response using a soluble form of human CTLA4Ig fusion protein would lead to persistent inhibition of alloreactive T cell activation. Methods: We have used CHO-$dhfr^-$ cell-line to produce CTLA4Ig fusion protein. After serum free culture of transfected cell line we purified this recombinant molecule by using protein A column. To confirm characterization of fusion protein, we carried out a series of Western blot, SDS-PAGE and silver staining analyses. We have also investigated the efficacy of CTLA4Ig in vitro such as mixed lymphocyte reaction (MLR) & cytotoxic T lymphocyte (CTL) response and in vivo such as experimental autoimmune encephalomyelitis (EAE), graft versus host disease (GVHD) and skin-graft whether this fusion protein could inhibit alloreactive T cell activation and lead to immunosuppression of activated T cell. Results: In vitro assay, CTLA4Ig fusion protein inhibited immune response in T cell-specific manner: 1) Human CTLA4Ig inhibited allogeneic stimulation in murine MLR; 2) CTLA4Ig prevented the specific killing activity of CTL. In vivo assay, human CTLA4Ig revealed the capacities to induce alloantigen-specific hyporesponsiveness in mouse model: 1) GVHD was efficiently blocked by dose-dependent manner; 2) Clinical score of EAE was significantly decreased compared to nomal control; 3) The time of skin-graft rejection was not different between CTLA4Ig treated and control group. Conclusion: Human CTLA4Ig suppress the T cell-mediated immune response and efficiently inhibit the EAE, GVHD in mouse model. The mechanism of T cell suppression by human CTLA4Ig fusion protein may be originated from the suppression of activity of cytotoxic T cell. Human CTLA4Ig could not suppress the rejection in mouse skin-graft, this finding suggests that other mechanism except the suppression of cytotoxic T cell may exist on the suppression of graft rejection.

• BMB Reports
• /
• 제52권12호
• /
• pp.718-727
• /
• 2019

Severe combined immunodeficiency (SCID) is a group of inherited disorders characterized by compromised T lymphocyte differentiation related to abnormal development of other lymphocytes [i.e., B and/or natural killer (NK) cells], leading to death early in life unless treated immediately with hematopoietic stem cell transplant. Functional NK cells may impact engraftment success of life-saving procedures such as bone marrow transplantation in human SCID patients. Therefore, in animal models, a T cell-/B cell-/NK cell+ environment provides a valuable tool for understanding the function of the innate immune system and for developing targeted NK therapies against human immune diseases. In this review, we focus on underlying mechanisms of human SCID, recent progress in the development of SCID animal models, and utilization of SCID pig model in biomedical sciences. Numerous physiologies in pig are comparable to those in human such as immune system, X-linked heritability, typical T-B+NK- cellular phenotype, and anatomy. Due to analogous features of pig to those of human, studies have found that immunodeficient pig is the most appropriate model for human SCID.

• BMB Reports
• /
• 제52권11호
• /
• pp.625-634
• /
• 2019

Severe combined immunodeficiency (SCID) is a group of inherited disorders characterized by compromised T lymphocyte differentiation related to abnormal development of other lymphocytes [i.e., B and/or natural killer (NK) cells], leading to death early in life unless treated immediately with hematopoietic stem cell transplant. Functional NK cells may impact engraftment success of life-saving procedures such as bone marrow transplantation in human SCID patients. Therefore, in animal models, a T cell-/B cell-/NK cell＋ environment provides a valuable tool for understanding the function of the innate immune system and for developing targeted NK therapies against human immune diseases. In this review, we focus on underlying mechanisms of human SCID, recent progress in the development of SCID animal models, and utilization of SCID pig model in biomedical sciences. Numerous physiologies in pig are comparable to those in human such as immune system, X-linked heritability, typical T-B＋NK- cellular phenotype, and anatomy. Due to analogous features of pig to those of human, studies have found that immunodeficient pig is the most appropriate model for human SCID.

• 생명과학회지
• /
• 제17권5호
• /
• pp.671-677
• /
• 2007

발효 및 비발효 차가버섯 수용성 추출물이 정상 세포주 NIH3T3 mouse normal fibroblast cell 및 인체 종양 세포주 AGS human gastric cancer cell(위암), HCT-15 human colon cancer cell(대장암), Hep3B human hepatoma cancer cell(간암), MCF-7 human breast cancer cell(유방암), HeLa human cervical cancer cell(자궁경부암)에서 MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay 방법에 의한 세포 증식 억제와 암세포 증식억제의 기전 연구의 일환으로 apoptosis가 일어날 때 나타나는 DNA fragmentation을 agarose gel electrophoresis 방법으로 검토하였다. 인체 종양 세포주의 생육저해 효과가 발효 차가버섯 추출물이 비발효 차가버섯 추출물보다 강한 것으로 나타났다. 그러나 동일한 실험조건하에서 마우스 정상 세포주 NIH3T3은 80% 이상의 생존율을 나타내어 정상 세포주에는 큰 영향을 미치지 않는 것으로 나타났다. 특히, 발효 및 비발효 차가버섯 추출물에서 본 실험에 사용한 세포주 중에서 대장암 세포주 HCT-15에 대해 가장 세포 증식 억제효과가 뛰어났으며, 이러한 효과는 첨가 농도 의존적 이였다. 발효 및 비발효 차가버섯 추출물에 의한 암세포 증식억제가 기전 연구로 apoptosis가 일어날 때 나타나는 DNA fragmentation을 세포로부터 genomic DNA를 분리하여 agarose gel electrophoresis 방법으로 조사한 결과, 정상세포인 NIH3T3 세포는 DNA fragmentation이 거의 일어나지 않아 세포 생존율 결과와 유사한 경향을 보였으나, 특히 대장암 세포주인 HCT-15에서는 발효 차가버섯뿐만 아니라 비발효 차가버섯 추출물에서도 DNA fragmentation이 많이 일어나는 것이 관찰되어 암세포 증식억제 효과가 높다는 결과를 뒷받침 해주고 있다.

• 한국환경성돌연변이발암원학회지
• /
• 제24권1호
• /
• pp.1-9
• /
• 2004

Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.