scholarly journals The promoter of the human interleukin-2 gene contains two octamer-binding sites and is partially activated by the expression of Oct-2

1990 ◽  
Vol 10 (10) ◽  
pp. 5464-5472
Author(s):  
M P Kamps ◽  
L Corcoran ◽  
J H LeBowitz ◽  
D Baltimore
Keyword(s):  
T Cells ◽  
Binding Sites ◽  
Interleukin 2 ◽  
Point Mutations ◽  
Transcriptional Response ◽  
Initiation Site ◽  
Gene Encoding ◽  
Transcriptional Initiation

The gene encoding interleukin-2 (IL-2) contains a sequence 52 to 326 nucleotides upstream of its transcriptional initiation site that promotes transcription in T cells that have been activated by costimulation with tetradecanoyl phorbol myristyl acetate (TPA) and phytohemagglutinin (PHA). We found that the ubiquitous transcription factor, Oct-1, bound to two previously identified motifs within the human IL-2 enhancer, centered at nucleotides -74 and -251. Each site in the IL-2 enhancer that bound Oct-1 in vitro was also required to achieve a maximal transcriptional response to TPA plus PHA in vivo. Point mutations within either the proximal or distal octamer sequences reduced the response of the enhancer to activation by 54 and 34%, respectively. Because the murine T-cell line EL4 constitutively expresses Oct-2 and requires only TPA to induce transcription of the IL-2 gene, the effect of Oct-2 expression on activation of the IL-2 promoter in Jurkat T cells was determined. Expression of Oct-2 potentiated transcription 13-fold in response to TPA plus PHA and permitted the enhancer to respond to the single stimulus of TPA. Therefore, both the signal requirements and the magnitude of the transcription response of the IL-2 promoter can be modulated by Oct-2.

scholarly journals The promoter of the human interleukin-2 gene contains two octamer-binding sites and is partially activated by the expression of Oct-2.

1990 ◽  
Vol 10 (10) ◽  
pp. 5464-5472 ◽  
Author(s):  
M P Kamps ◽  
L Corcoran ◽  
J H LeBowitz ◽  
D Baltimore
Keyword(s):  
T Cells ◽  
Binding Sites ◽  
Interleukin 2 ◽  
Point Mutations ◽  
Transcriptional Response ◽  
Initiation Site ◽  
Gene Encoding ◽  
Transcriptional Initiation

The gene encoding interleukin-2 (IL-2) contains a sequence 52 to 326 nucleotides upstream of its transcriptional initiation site that promotes transcription in T cells that have been activated by costimulation with tetradecanoyl phorbol myristyl acetate (TPA) and phytohemagglutinin (PHA). We found that the ubiquitous transcription factor, Oct-1, bound to two previously identified motifs within the human IL-2 enhancer, centered at nucleotides -74 and -251. Each site in the IL-2 enhancer that bound Oct-1 in vitro was also required to achieve a maximal transcriptional response to TPA plus PHA in vivo. Point mutations within either the proximal or distal octamer sequences reduced the response of the enhancer to activation by 54 and 34%, respectively. Because the murine T-cell line EL4 constitutively expresses Oct-2 and requires only TPA to induce transcription of the IL-2 gene, the effect of Oct-2 expression on activation of the IL-2 promoter in Jurkat T cells was determined. Expression of Oct-2 potentiated transcription 13-fold in response to TPA plus PHA and permitted the enhancer to respond to the single stimulus of TPA. Therefore, both the signal requirements and the magnitude of the transcription response of the IL-2 promoter can be modulated by Oct-2.

scholarly journals A bispecific antibody agonist of the IL-2 heterodimeric receptor preferentially promotes in vivo expansion of CD8 and NK cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katherine E. Harris ◽  
Kyle J. Lorentsen ◽  
Harbani K. Malik-Chaudhry ◽  
Kaitlyn Loughlin ◽  
Harish Medlari Basappa ◽  
...  
Keyword(s):  
T Cells ◽  
Nk Cells ◽  
Bispecific Antibody ◽  
T Regulatory Cells ◽  
Tumor Regression ◽  
Interleukin 2 ◽  
In Vivo Studies ◽  
Preferential Binding

AbstractThe use of recombinant interleukin-2 (IL-2) as a therapeutic protein has been limited by significant toxicities despite its demonstrated ability to induce durable tumor-regression in cancer patients. The adverse events and limited efficacy of IL-2 treatment are due to the preferential binding of IL-2 to cells that express the high-affinity, trimeric receptor, IL-2Rαβγ such as endothelial cells and T-regulatory cells, respectively. Here, we describe a novel bispecific heavy-chain only antibody which binds to and activates signaling through the heterodimeric IL-2Rβγ receptor complex that is expressed on resting T-cells and NK cells. By avoiding binding to IL-2Rα, this molecule circumvents the preferential T-reg activation of native IL-2, while maintaining the robust stimulatory effects on T-cells and NK-cells in vitro. In vivo studies in both mice and cynomolgus monkeys confirm the molecule’s in vivo biological activity, extended pharmacodynamics due to the Fc portion of the molecule, and enhanced safety profile. Together, these results demonstrate that the bispecific antibody is a safe and effective IL-2R agonist that harnesses the benefits of the IL-2 signaling pathway as a potential anti-cancer therapy.

scholarly journals In Vivo Role of Dendritic Cells in a Murine Model of Pulmonary Cryptococcosis

2006 ◽  
Vol 74 (7) ◽  
pp. 3817-3824 ◽  
Author(s):  
Karen L. Wozniak ◽  
Jatin M. Vyas ◽  
Stuart M. Levitz
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell Activation ◽  
Cell Activation ◽  
Ex Vivo ◽  
Interleukin 2 ◽  
Mouse Lung

ABSTRACT Dendritic cells (DC) have been shown to phagocytose and kill Cryptococcus neoformans in vitro and are believed to be important for inducing protective immunity against this organism. Exposure to C. neoformans occurs mainly by inhalation, and in this study we examined the in vivo interactions of C. neoformans with DC in the lung. Fluorescently labeled live C. neoformans and heat-killed C. neoformans were administered intranasally to C57BL/6 mice. At specific times postinoculation, mice were sacrificed, and lungs were removed. Single-cell suspensions of lung cells were prepared, stained, and analyzed by microscopy and flow cytometry. Within 2 h postinoculation, fluorescently labeled C. neoformans had been internalized by DC, macrophages, and neutrophils in the mouse lung. Additionally, lung DC from mice infected for 7 days showed increased expression of the maturation markers CD80, CD86, and major histocompatibility complex class II. Finally, ex vivo incubation of lung DC from infected mice with Cryptococcus-specific T cells resulted in increased interleukin-2 production compared to the production by DC from naïve mice, suggesting that there was antigen-specific T-cell activation. This study demonstrated that DC in the lung are capable of phagocytosing Cryptococcus in vivo and presenting antigen to C. neoformans-specific T cells ex vivo, suggesting that these cells have roles in innate and adaptive pulmonary defenses against cryptococcosis.

scholarly journals TRAF6 inhibits Th17 differentiation and TGF-β–mediated suppression of IL-2

Blood ◽  
2010 ◽  
Vol 115 (23) ◽  
pp. 4750-4757 ◽  
Author(s):  
Pedro J. Cejas ◽  
Matthew C. Walsh ◽  
Erika L. Pearce ◽  
Daehee Han ◽  
Gretchen M. Harms ◽  
...  
Keyword(s):  
T Cells ◽  
Transforming Growth Factor ◽  
Interleukin 2 ◽  
Transforming Growth Factor Β ◽  
Main Function ◽  
Normal Numbers ◽  
T Helper 17 ◽  
Th17 Differentiation

Abstract Transforming growth factor-β (TGF-β) has an essential role in the generation of inducible regulatory T (iTreg) and T helper 17 (Th17) cells. However, little is known about the TGF-β–triggered pathways that drive the early differentiation of these cell populations. Here, we report that CD4+ T cells lacking the molecular adaptor tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) exhibit a specific increase in Th17 differentiation in vivo and in vitro. We show that TRAF6 deficiency renders T cells more sensitive to TGF-β–induced Smad2/3 activation and proliferation arrest. Consistent with this, in TRAF6-deficient T cells, TGF-β more effectively down-regulates interleukin-2 (IL-2), a known inhibitor of Th17 differentiation. Remarkably, TRAF6-deficient cells generate normal numbers of Foxp3-expressing cells in iTreg differentiation conditions where exogenous IL-2 is supplied. These findings show an unexpected role for the adaptor molecule TRAF6 in Smad-mediated TGF-β signaling and Th17 differentiation. Importantly, the data also suggest that a main function of TGF-β in early Th17 differentiation may be the inhibition of autocrine and paracrine IL-2–mediated suppression of Th17 cell generation.

“In vivo” activated splenic T cells are refractory to interleukin 2 growth “in vitro”

1987 ◽  
Vol 17 (7) ◽  
pp. 901-908 ◽  
Author(s):  
António Bandeira ◽  
Eva-Lotta Larsson ◽  
Luciana Forni ◽  
Pablo Pereira ◽  
António Coutinho
Keyword(s):  
T Cells ◽  
Interleukin 2

scholarly journals IL-2 administration increases CD4+CD25hi Foxp3+ regulatory T cells in cancer patients

Blood ◽  
2006 ◽  
Vol 107 (6) ◽  
pp. 2409-2414 ◽  
Author(s):  
Mojgan Ahmadzadeh ◽  
Steven A. Rosenberg
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Interleukin 2 ◽  
Selective Inhibition ◽  
High Dose ◽  
Protein Levels ◽  
And Function ◽  
The Impact

Abstract Interleukin-2 (IL-2) is historically known as a T-cell growth factor. Accumulating evidence from knockout mice suggests that IL-2 is crucial for the homeostasis and function of CD4+CD25+ regulatory T cells in vivo. However, the impact of administered IL-2 in an immune intact host has not been studied in rodents or humans. Here, we studied the impact of IL-2 administration on the frequency and function of human CD4+CD25hi T cells in immune intact patients with melanoma or renal cancer. We found that the frequency of CD4+CD25hi T cells was significantly increased after IL-2 treatment, and these cells expressed phenotypic markers associated with regulatory T cells. In addition, both transcript and protein levels of Foxp3, a transcription factor exclusively expressed on regulatory T cells, were consistently increased in CD4 T cells following IL-2 treatment. Functional analysis of the increased number of CD4+CD25hi T cells revealed that this population exhibited potent suppressive activity in vitro. Collectively, our results demonstrate that administration of high-dose IL-2 increased the frequency of circulating CD4+CD25hi Foxp3+ regulatory T cells. Our findings suggest that selective inhibition of IL-2-mediated enhancement of regulatory T cells may improve the therapeutic effectiveness of IL-2 administration. (Blood. 2006;107:2409-2414)

scholarly journals Immunotherapy of a murine tumor with interleukin 2. Increased sensitivity after MHC class I gene transfection.

1987 ◽  
Vol 166 (6) ◽  
pp. 1716-1733 ◽  
Author(s):  
J S Weber ◽  
G Jay ◽  
K Tanaka ◽  
S A Rosenberg
Keyword(s):  
T Cells ◽  
Mhc Class I ◽  
Interleukin 2 ◽  
Class I ◽  
High Dose ◽  
Class I Mhc ◽  
High Doses ◽  
I Gene

We have shown that two weakly immunogenic MCA sarcomas developed in our laboratory that are sensitive to high-dose IL-2 immunotherapy express class I MHC in vivo and in vitro. Two nonimmunogenic MCA sarcomas are relatively insensitive to IL-2 therapy and express minimal or no class I MHC molecules in vivo and in vitro. To study the role of MHC in the therapy of tumors with IL-2, a class I-deficient murine melanoma, B16BL6, was transfected with the Kb class I gene. Expression of class I MHC rendered B16BL6 advanced pulmonary macrometastases sensitive to IL-2 immunotherapy. 3-d micrometastases of CL8-2, a class I transfected clone of B16BL6, were significantly more sensitive to IL-2 therapy than a control nontransfected line. Expression of Iak, a class II MHC molecule, had no effect on IL-2 therapy of transfectant pulmonary micrometastases in F1 mice. By using lymphocyte subset depletion with mAbs directed against Lyt-2, therapy of class I transfectant macrometastases with high-dose IL-2 was shown to involve an Lyt-2 cell. In contrast, regression of micrometastases treated with low-dose IL-2 involved Lyt-2+ cells, but regression mediated by high doses of IL-2 did not. We hypothesize that both LAK and Lyt-2+ T cells effect IL-2-mediated elimination of micrometastases, but only Lyt-2+ T cells are involved in macrometastatic regression. Low doses of IL-2 stimulate Lyt-2+ cells to eliminate class I-expressing micrometastases, but high doses of IL-2 can recruit LAK cells to mediate regression of micrometastases independent of class I expression. Only high-dose IL-2, mediating its effect predominantly via Lyt-2+ cells, is capable of impacting on MHC class I-expressing macrometastases. Macrometastases devoid of class I MHC antigens appear to be resistant to IL-2 therapy.

scholarly journals A yeast ARS-binding protein activates transcription synergistically in combination with other weak activating factors.

1990 ◽  
Vol 10 (3) ◽  
pp. 887-897 ◽  
Author(s):  
A R Buchman ◽  
R D Kornberg
Keyword(s):  
Dna Sequences ◽  
Transcriptional Activation ◽  
Binding Sites ◽  
Essential Gene ◽  
Specific Binding ◽  
Binding Protein ◽  
Point Mutations ◽  
Yeast Genes

ABFI (ARS-binding protein I) is a yeast protein that binds specific DNA sequences associated with several autonomously replicating sequences (ARSs). ABFI also binds sequences located in promoter regions of some yeast genes, including DED1, an essential gene of unknown function that is transcribed constitutively at a high level. ABFI was purified by specific binding to the DED1 upstream activating sequence (UAS) and was found to recognize related sequences at several other promoters, at an ARS (ARS1), and at a transcriptional silencer (HMR E). All ABFI-binding sites, regardless of origin, provided weak UAS function in vivo when examined in test plasmids. UAS function was abolished by point mutations that reduced ABFI binding in vitro. Analysis of the DED1 promoter showed that two ABFI-binding sites combine synergistically with an adjacent T-rich sequence to form a strong constitutive activator. The DED1 T-rich element acted synergistically with all other ABFI-binding sites and with binding sites for other multifunctional yeast activators. An examination of the properties of sequences surrounding ARS1 left open the possibility that ABFI enhances the initiation of DNA replication at ARS1 by transcriptional activation.

scholarly journals T cell-mediated eradication of murine metastatic melanoma induced by targeted interleukin 2 therapy.

1996 ◽  
Vol 183 (5) ◽  
pp. 2361-2366 ◽  
Author(s):  
J C Becker ◽  
J D Pancook ◽  
S D Gillies ◽  
K Furukawa ◽  
R A Reisfeld
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Nk Cell ◽  
Interleukin 2 ◽  
Tumor Model ◽  
Melanoma Metastases ◽  
Tumor Eradication

Induction of a T-cell mediated antitumor response is the ultimate goal for tumor immunotherapy. We demonstrate here that antibody-targeted IL2 therapy is effective against established pulmonary and hepatic melanoma metastases in a syngeneic murine tumor model. The effector mechanisms involved in this tumor eradication are not dependent on NK cells, since the therapeutic effect of antibody-IL2 fusion protein was not altered in NK cell-deficient mice. In contrast, T cells are essential for the observed antitumor effect, since therapy with antibody IL2 fusion proteins is unable to induce tumor eradication in T cell-deficient SCID mice. In vivo depletion studies characterized the essential effector cell population further as CD8 + T cells. Such CD8 + T cells, isolated from tumor bearing mice after antibody-directed IL2 therapy, exerted a MHC class I-restricted cytotoxicity against the same tumor in vitro. These data demonstrate the ability of antibody-targeted IL2 delivery to induce a T cell-dependent host immune response that is capable of eradicating established melanoma metastases in clinically relevant organs.

scholarly journals Differentiation of T cell lymphokine gene expression: the in vitro acquisition of T cell memory.

1991 ◽  
Vol 173 (1) ◽  
pp. 25-36 ◽  
Author(s):  
S Ehlers ◽  
K A Smith
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
Interleukin 2 ◽  
Experimental System ◽  
Functional Differentiation ◽  
Gene Repertoire ◽  
Anamnestic Response

A simple in vitro experimental system was devised to reflect the in vivo generation of a T cell anamnestic response so that T cell differentiation could be examined at the level of lymphokine gene expression. Comparison of neonatal and adult T cells revealed that both populations expressed the genes for interleukin 2 (IL-2) and its receptor, but only adult T cells were capable of transcribing mRNAs for IL-3, IL-4, IL-5, IL-6, interferon gamma, and granulocyte/macrophage colony-stimulating factor. However, neonatal T cells could be induced to undergo functional differentiation in vitro, thereby acquiring the capacity to express the lymphokine gene repertoire characteristic for adult T cells. These data suggest that the T cells generated from neonatal blood by a primary stimulation in vitro are functionally indistinguishable from the T cells in adult blood that presumably have undergone primary stimulation in vivo. Therefore, we propose that the term "memory cell" be applied to those T cells that can be identified by their differentiated state of inducible effector-lymphokine gene expression.

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