• 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.

• Tuberculosis and Respiratory Diseases
• /
• 제42권6호
• /
• pp.823-830
• /
• 1995

연구배경: 결핵감염시 세포매개성 면역반응이 관여하여 말초혈액내 조력 T 세포가 감소하는 것으로 알려저왔다. 그러나 말초혈액내 표지물질을 가진 세포의 수적 감소가 세포매개성 면연반응의 저하라고 할 수있지 여부가 앞으로 해결해야 될 문제인 것으로 지적되고 있다. 이에 저자들은 폐결핵 환자들의 말초혈액에서 활성화된, 또는 활성화 되고 있은 세포의 수적변화를 관찰하기 위하여 본 연구를 시행하였다. 방법: 객담 결핵균 양성인 폐결핵 환자 22명을 대상으로 말초혈액에서 IL-2R, VLA-1, TLiSAI의 활성화 표지에 대한 단세포군 항체를 면역조직 화학법으로 측정하였다. 결과: 1) 폐결핵 환자의 말포혈액에서 $T_1$(+) 세포 및 그 아형들의 단위 부피당 절대수는 $T_4$(+) 세포는 유의하게 감소하였고 $T_8$(+) 세포는 증가하였다(p<0.05). 2) 폐결핵 환자에서 전체 T임파구의 비율은 감소되어 있으며 $T_4$(+) 세포, $T_8$(+) 세포비율은 각각 유의하게 감소, 증가하였다. 또한 $T_4(+)/T_8(+)$ 비율도 유의한 감소가 있었다(p<0.05). 3) 폐결핵 환자에서 activated T cell의 단위 부피당 절대수는 대조군에 비해 모두 유의한 증가를 보였다(p<0.05). 4) 폐결핵 환자에서 activated T cell 비율은, IL-2R, VLA-1, TLiSAI, 각각 6.45+1.56%, 7.64+1.34%, 10.45+1.16%로 모두 대조군에 비해 모두 유의한 증가를 보이며 특히 TLiSAI 항체가 가장 많이 관찰 되었다. 결론: 폐결핵 감염시 말초혈액 임파구의 일부만이 활성화되어 세포매개성 면역반응에 참여하는 것으로 사료된다.

• Molecules and Cells
• /
• 제38권10호
• /
• pp.918-924
• /
• 2015

During T cell activation, mitochondrial content increases to meet the high energy demand of rapid cell proliferation. With this increase, the level of reactive oxygen species (ROS) also increases and causes the rapid apoptotic death of activated cells, thereby facilitating T cell homeostasis. Nicotinamide (NAM) has previously been shown to enhance mitochondria quality and extend the replicative life span of human fibroblasts. In this study, we examined the effect of NAM on $CD8^+$ T cell activation. NAM treatment attenuated the increase of mitochondrial content and ROS in T cells activated by CD3/CD28 antibodies. This was accompanied by an accelerated and higher-level clonal expansion resulting from attenuated apoptotic death but not increased division of the activated cells. Attenuation of ROS-triggered pro-apoptotic events and upregulation of Bcl-2 expression appeared to be involved. Although cells activated in the presence of NAM exhibited compromised cytokine gene expression, our results suggest a means to augment the size of T cell expansion during activation without consuming their limited replicative potential.

• 생약학회지
• /
• 제35권4호통권139호
• /
• pp.330-337
• /
• 2004

Based on the traditional application of Carthamus tinctorious L. (CF) as a component of Korean medicinal decoctions, in the present study, we investigated in vitro an immunomodulatory activity of water extract of CF(WECF). Water extract of CF significantly increased the in vitro proliferative responses of spleen cells (SPC). However, addition of WECF during anti-CD3 activation resulted in a significant decrease in SPC proliferation. Flow cytometric analysis showed that WECF addition chanced T and B cell frequencies in anti-CD3-activated spleen cell populations. Using purified cells, it was revealed that WECF is mitogenic to B cells but rather inhibitory to T cell Proliferation. Upon anti-CD3 stimulation, high concentration (1 mg/ml) of WECF significantly inhibited T cell proliferation until day 2 of stimulation. At day 3, anti-CD3-activated cells exposed to WECF recovered their proliferation to the level comparable to control. Although B cell proliferation was also inhibited in proliferation at day 1, it recovered sooner and then was rather augmented by WECF at day 3. These data indicate that WECF down-regulates lymphocyte proliferation at early phase of activation but T cells are more vulnerable than B cells to WECF, However, CD4+ and CD8+ T cells did not differ in WECF-mediated immunotoxicity. Data of propidium iodide (PI) staining showed that WECF accelerates activated T cell, but not B cell, apoptosis and WECF concurrently inhibited cytokine production of activated T cells. Taken together, WECF exhibits B cell mitogenic activity and differential toxicity more pronounced to T cells, suggesting a possible in vivo application of WECF for specific control of T cells without alteration of B cell activity.

• 생명과학회지
• /
• 제21권2호
• /
• pp.316-321
• /
• 2011

Indoleamine 2,3-dioxygenase (IDO)에 의한 트립토판 대사체의 생성은 T 세포에 강력한 억제효과를 미치지만 여전히 그 작용기전에 대한 연구보고는 미비한 실정이다. 본 연구자는 트립토판 대사체 3-HAA가 선택적으로 활성 T 세포의 사멸을 촉진시키는 효과가 있음을 확인하였고, 이는 세포주기 억제와는 관련이 없었다. 3-HAA 처리 시 활성 T 세포에서 TRAIL과 그의 수용체의 발현이 현저히 증가하고, 이들 상호작용을 차단하였을 때 3-HAA-매개 활성 T 세포사멸 효과가 유의하게 낮아졌다. 본 연구를 통해 트립토판 대사체 3-HAA의 선택적 T 세포 억제 효과가 TRAIL-유도 세포사멸과 관련됨을 알 수 있다.

• IMMUNE NETWORK
• /
• 제3권1호
• /
• pp.8-15
• /
• 2003

Background: CD30 is a member of TNF receptor family and expressed on lymphocytes and other hematopoietic cells following activation as well as Hodgkin and Reed-Sternberg cells in Hodgkin's lymphoma. In this study, CD30-mediated regulation of cell adhesion molecule expression on normal activated mouse T cells was investigated. Methods: Mouse T cells were activated with anti-CD3 antibody for induction of CD30, which was cross-linked by immobilized anti-CD30 antibody. Results: High level of CD30 expression on T cells was observed on day 5, but only little on day 3 even under culture condition resulting in an identical T cell proliferation, indicating that CD30 expression requires a prolonged stimulation up to 5 days. Cross-linking of CD30 alone altered neither proliferation nor apoptosis of normal activated T cells. Instead, CD30 appeared to promote cell adherence to culture substrate, and considerably upregulated ICAM-1 and, to a lesser extent, ICAM-2 expression on activated T cells, whereas CD2 and CD18 (LFA-1) expression was not affected. None of cytokines known as main regulators of ICAM-1 expression on tissue cells (IL 4, $IFN{\gamma}$ and $IFN{\alpha}$) enhanced ICAM-1 expression in the absence of CD30 signals. On the other hand, addition of $NF-{\kappa}B$ inhibitor, PDTC (0.1 mM) completely abrogated the CD30-mediated upregulation of ICAM-1 expression, but not CD2 and ICAM-2 expression. Conclusion: This results support that CD30 upregulates ICAM-1 expression of T cell and such regulation is not mediated by higher cytokine production but $NF-{\kappa}B$ activation. Therefore, CD30 may play important roles in T-T or T-B cell interaction through regulation of ICAM-1, and -2 expression.

• Animal cells and systems
• /
• 제8권2호
• /
• pp.125-133
• /
• 2004

We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.

• IMMUNE NETWORK
• /
• 제10권5호
• /
• pp.153-163
• /
• 2010

Background: In addition to TCR and costimulatory signals, cytokine signals are required for the differentiation of activated CD8 T cells into memory T cells and their survival. Previously, we have shown that IL-12 priming during initial antigenic stimulation significantly enhanced the survival of activated CD8 T cells and increased the memory cell population. In the present study, we analyzed the mechanisms by which IL-12 priming contributes to activation and survival of CD8 T cells. Methods: We observed dramatically decreased expression of CD43 in activated CD8 T cells by IL-12 priming. We purified $CD43^{lo}$ and $CD43^{hi}$ cells after IL-12 priming and analyzed the function and survival of each population both in vivo and in vitro. Results: Compared to $CD43^{hi}$ effector cells, $CD43^{lo}$ effector CD8 T cells exhibited reduced cytolytic activity and lower granzyme B expression but showed increased survival. $CD43^{lo}$ effector CD8 T cells also showed increased in vivo expansion after adoptive transfer and antigen challenge. The enhanced survival of $CD43^{lo}$ CD8 T cells was also partly associated with CD62L expression. Conclusion: We suggest that CD43 expression regulated by IL-12 priming plays an important role in differentiation and survival of CD8 T cells.

• Journal of Microbiology and Biotechnology
• /
• 제16권6호
• /
• pp.911-920
• /
• 2006

[ $CD8^+$ ] T Iymphocytes with the cytotoxic activity and capability to release various cytokines are the major players in immune responses against viral infection and cancer. To identify the proteins specific to resting or activated human CD8$^+$ T cells, human CD8$^+$ T cells were activated with anti-CD3+anti-CD28 mAb in the presence of IL-2. The solubilized proteins from resting and activated human CD8$^+$ T cells were separated by high-resolution two-dimensional polyacrylamide gel electrophoresis, and their proteomes were analyzed. Proteomic analysis of resting and activated T cells resulted in identification of 35 proteins with the altered expression. Mass spectrometry coupled with Profound and SWISS-PROT database analysis revealed that these identified proteins are to be functionally associated with cell proliferation, metabolic pathways, antigen presentation, and intracellular signal transduction pathways. We also identified six unknown proteins predicted from genomic DNA sequences specific to resting or activated CD8$^+$ T cells. Protein network studies and functional characterization of these novel proteins may provide new insight into the signaling transduction pathway of CD8$^+$ T cell activation.

• BMB Reports
• /
• 제55권2호
• /
• pp.57-64
• /
• 2022

Autoimmune disease is known to be caused by unregulated self-antigen-specific T cells, causing tissue damage. Although antigen specificity is an important mechanism of the adaptive immune system, antigen non-related T cells have been found in the inflamed tissues in various conditions. Bystander T cell activation refers to the activation of T cells without antigen recognition. During an immune response to a pathogen, bystander activation of self-reactive T cells via inflammatory mediators such as cytokines can trigger autoimmune diseases. Other antigen-specific T cells can also be bystander-activated to induce innate immune response resulting in autoimmune disease pathogenesis along with self-antigen-specific T cells. In this review, we summarize previous studies investigating bystander activation of various T cell types (NKT, γδ T cells, MAIT cells, conventional CD4⁺, and CD8⁺ T cells) and discuss the role of innate-like T cell response in autoimmune diseases. In addition, we also review previous findings of bystander T cell function in infection and cancer. A better understanding of bystander-activated T cells versus antigen-stimulated T cells provides a novel insight to control autoimmune disease pathogenesis.