The murine T cell line CT6 provides a novel bioassay for interleukin‐7

Willcocks, Joanie L.; Hales, Anne; Page, Theresa H.; Foxwell, Brian M. J.

doi:10.1002/eji.1830230322

Cited by 9 publications

(10 citation statements)

References 19 publications

(6 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1, c and d) and was maximal at 2 ng/ml (100 pM). This correlates with the proliferative response of CT6 to either cytokine (46). As expected, activated SAPK/JNK was also immunoprecipitated from T cells stressed with anisomycin (Fig.…”

Section: Il-2 and Il-7supporting

confidence: 81%

T Cell Proliferation in Response to Interleukins 2 and 7 Requires p38MAP Kinase Activation

Crawley¹,

Rawlinson²,

Lali³

et al. 1997

Journal of Biological Chemistry

Self Cite

231

133

View full text Add to dashboard Cite

Interleukin-2 (IL-2) is a potent T cell mitogen. However, the signaling pathways by which IL-2 mediates its mitogenic effect are not fully understood. One of the members of the mitogen-activated protein kinase (MAPK) family, p42/44MAPK (ERK2/1), is known to be activated by IL-2. We have now investigated the response to IL-2 of two other members of the MAP kinase family, p54MAP kinase (stress-activated protein kinase (SAPK)/Jun-N-terminal kinase (JNK)) and p38MAP kinase (p38/Mpk2/CSBP/RK), which respond primarily to stressful and inflammatory stimuli (e.g. tumor necrosis factor-␣, IL-1, and lipopolysaccharide). Here we show that IL-2, and another T cell growth factor, IL-7, activate both SAPK/JNK and p38MAP kinase. Furthermore, inhibition of p38MAP kinase activity with a specific pyrinidyl imidazole inhibitor SB203580 that prevents activation of its downstream effector, MAPK-activating protein kinase-2, correlated with suppression of IL-2-and IL-7-driven T cell proliferation. These data indicate that in T cells p38MAP kinase has a role in transducing the mitogenic signal.

show abstract

Section: Il-2 and Il-7supporting

confidence: 81%

T Cell Proliferation in Response to Interleukins 2 and 7 Requires p38MAP Kinase Activation

Crawley¹,

Rawlinson²,

Lali³

et al. 1997

Journal of Biological Chemistry

Self Cite

231

133

View full text Add to dashboard Cite

show abstract

“…Cellular proliferation was measured over a 24-h period of mitogen stimulation using thymidine incorporation, as previously described (17). In all experiments, the sample shown in the absence of drug treatment contained the vehicle (DMSO) at the highest concentration (0.3%).…”

Section: Cellular Proliferationmentioning

confidence: 99%

A Late, Prolonged Activation of the Phosphatidylinositol 3-Kinase Pathway Is Required for T Cell Proliferation

Lali

Crawley

McCulloch

et al. 2004

The Journal of Immunology

Self Cite

View full text Add to dashboard Cite

Activation of the phosphatidylinositol-3 kinase (PI 3-K) pathway is associated with the proliferation of many cell types, including T lymphocytes. However, recent studies in cell lines stably expressing deletion mutants of IL-2R that fail to activate PI 3-K have questioned the requirement for this pathway in cell cycle regulation. In this study with IL-2 and IL-7, we show in primary T cells that, unlike IL-2, IL-7 fails to induce the early activation of PI 3-K seen within minutes and normally associated with cytokine signaling. However, kinetic experiments showed that both of these T cell growth factors induce a distinct and sustained phase of PI 3-K activity several hours after stimulation. This delayed activation correlates with cell cycle induction and from studies using inhibitors of PI 3-K signaling, we show that this later phase, unlike the early activation within minutes, is required for cell cycle induction. The data presented here will have major implications for our understanding of the mechanism of T cell proliferation as well as the regulation of PI 3-K activity.

show abstract

“…The IL-2-dependent murine T cell line, CT6, was grown and maintained as described previously (12). These cells were rested by washing three times in RPMI and culturing overnight in RPMI, 5% fetal calf serum in the absence of growth factor, antibiotics, or ␤-mercaptoethanol supplements.…”

Section: Cells and Proliferation Assaymentioning

confidence: 99%

“…Human peripheral blood mononuclear cells were prepared from buffy coat leukophoresis residues (North London Blood Transfusion Service, Colindale, London UK) and activated with 50 ng/ml OKT3 for 48 h. The cells were then washed extensively, rested overnight, and washed again before activating with IL-2; such cell preparations were Ͼ90% T cells (14). Cellular proliferation assays were performed by measurement of [ 3 H]thymidine incorporation as described previously (12).…”

Section: Cells and Proliferation Assaymentioning

confidence: 99%

The Pyridinyl Imidazole Inhibitor SB203580 Blocks Phosphoinositide-dependent Protein Kinase Activity, Protein Kinase B Phosphorylation, and Retinoblastoma Hyperphosphorylation in Interleukin-2-stimulated T Cells Independently of p38 Mitogen-activated Protein Kinase

Lali¹,

Hunt²,

Turner³

et al. 2000

Journal of Biological Chemistry

294

201

View full text Add to dashboard Cite

Pyridinyl imidazole inhibitors, particularly SB203580, have been widely used to elucidate the roles of p38 mitogen-activated protein (MAP) kinase (p38/HOG/SAP-KII) in a wide array of biological systems. Studies by this group and others have shown that SB203580 can have antiproliferative activity on cytokine-activated lymphocytes. However, we recently reported that the antiproliferative effects of SB203580 were unrelated to p38 MAP kinase activity. This present study now shows that SB203580 can inhibit the key cell cycle event of retinoblastoma protein phosphorylation in interleukin-2-stimulated T cells. Studies on the proximal regulator of this event, the phosphatidylinositol 3-kinase/protein kinase B (PKB)(Akt/Rac) kinase pathway, showed that SB203580 blocked the phosphorylation and activation of PKB by inhibiting the PKB kinase, phosphoinositidedependent protein kinase 1. The concentrations of SB203580 required to block PKB phosphorylation (IC 50 3-5 M) are only approximately 10-fold higher than those required to inhibit p38 MAP kinase (IC 50 0.3-0.5 M). These data define a new activity for this drug and would suggest that extreme caution should be taken when interpreting data where SB203580 has been used at concentrations above 1-2 M. Interleukin-2 (IL-2)1 is a potent T cell growth factor that mediates its effects via a high affinity heterotrimeric receptor comprising ␣, ␤, and ␥ c subunits. Several intracellular signaling pathways are known to be activated by IL-2, including the p42/44 mitogen-activated protein kinase (MAP kinase, also known as ERK2/1), the p38 and p54 MAP kinases (also called stress kinases, or HOG and JNK, respectively), the phosphatidyl inositol 3Ј (PI) 3-kinase pathway and the Jak/STAT (signal transducer and activator of transcription) pathways. Our earlier studies using the MEK (mitogen-activated protein kinase/ extracellular signal-regulated kinase kinase) inhibitor PD-098059 (1) and those of others (2, 3) have indicated that the p42/44 MAP kinase pathway is not required for IL-2-driven proliferation. In contrast, a pyridinyl imidazole inhibitor of p38 MAP kinase, SB203580, inhibited IL-2-driven T cell proliferation with an IC 50 of 3-5 M, suggesting a possible role for p38 MAP kinase in this process (4). Recently, we have further investigated the role of p38 MAP kinase in proliferation by mapping the subdomains of the IL-2 receptor ␤ chain involved in the activation of the kinase. As previously shown for p42/44 MAP kinase, activation of p38 and p54 MAP kinases required the acidic rich A region of the IL-2 receptor ␤ chain (5). However, the A region is not required for proliferation (2, 5), indicating that neither p38 MAP kinase nor p54 MAP kinase is essential for this function. Furthermore, CNI-1493 (6, 7), an inhibitor of p38 and p54 MAP kinase activation by IL-2 was unable to inhibit proliferation (5). Surprisingly, SB203580 was still able to inhibit proliferation in the absence of IL-2 stimulated p38 MAP kinase activation. It has already been reported that SB203580 does inhibit p54...

show abstract

The murine T cell line CT6 provides a novel bioassay for interleukin‐7

Cited by 9 publications

References 19 publications

T Cell Proliferation in Response to Interleukins 2 and 7 Requires p38MAP Kinase Activation

T Cell Proliferation in Response to Interleukins 2 and 7 Requires p38MAP Kinase Activation

A Late, Prolonged Activation of the Phosphatidylinositol 3-Kinase Pathway Is Required for T Cell Proliferation

The Pyridinyl Imidazole Inhibitor SB203580 Blocks Phosphoinositide-dependent Protein Kinase Activity, Protein Kinase B Phosphorylation, and Retinoblastoma Hyperphosphorylation in Interleukin-2-stimulated T Cells Independently of p38 Mitogen-activated Protein Kinase

Contact Info

Product

Resources

About