scholarly journals Immunoregulation of murine myeloma in vitro. II. Suppression of MOPC-315 immunoglobulin secretion and synthesis by idiotype-specific suppressor T cells.

1982 ◽  
Vol 155 (3) ◽  
pp. 852-862 ◽  
Author(s):  
G L Milburn ◽  
R G Lynch
Keyword(s):  
T Cells ◽  
Surface Membrane ◽  
Selective Inhibition ◽  
Myeloma Cell ◽  
Membrane Expression ◽  
Dose Dependent ◽  
Specific Suppressor T Cells ◽  
Insight Into

In previous studies, BALB/c mice immunized with trinitrophenyl-specific IgA protein (M315) produced by MOPC-315 developed idiotype (Id315)-specific T cells that suppressed M315 secretion in vivo. In the present in vitro studies, we show that inhibition of M315 secretion is mediated by a theta,Lyt-1-2+ cell that expresses a surface membrane receptor for Id315. The suppressor signal is a diffusable product that acts directly on M315-secreting myeloma cells. Inhibition of M315 secretion is T cell dose-dependent, Id315-specific, reversible, and occurs without any effect on MOPC-315 growth, viability, or surface membrane expression of M315. Inhibition of M315 secretion results from a selective inhibition of M315 synthesis in the myeloma cell. These studies provide new insight into the mechanisms of direct B cell regulation by idiotype-specific T cells.

scholarly journals Mechanisms of idiotype suppression. I. In vitro generation of idiotype-specific suppressor T cells by anti-idiotype antibodies and specific antigen.

1979 ◽  
Vol 149 (6) ◽  
pp. 1371-1378 ◽  
Author(s):  
B S Kim
Keyword(s):  
T Cells ◽  
Specific Antigen ◽  
Suppressor Cells ◽  
Culture Period ◽  
Spleen Cells ◽  
Suppressor T Cells ◽  
Myeloma Protein ◽  
Specific Suppressor T Cells

Normal BALB/c spleen cells are unresponsive in vitro to the phosphorylcholine (PC) determinant in the presence of anti-idiotype antibodies specific for the TEPC-15 myeloma protein (T15) which carries an idiotypic determinant indistinguishable from that of most anti-PC antibodies in BALB/c mice. The possibility that idiotype-specific suppressor cells may be generated during the culture period was examined by coculturing the cells with untreated syngeneic spleen cells. Cells that had been preincubated with anti-T15 idiotype (anti-T15id) antibodies and a PC-containing antigen, R36a for 3 d, were capable of specifically suppressing the anti-PC response of fresh normal spleen cells, indicating that idiotype-specific suppressor cells were generated during the culture period. The presence of specific antigen also appeared to be necessary because anti-T15id antibodies and a control antigen, DNP-Lys-Ficoll, were not capable of generating such suppressor cells. Suppressor cells were induced only in the population of spleen cells nonadherent to nylon wool and the suppressive activity was abrogated by treatment with anti-Thy 1.2 serum and complement. These results indicate that anti-idiotype antibodies and specific antigen can generate idiotype-specific suppressor T cells in vitro. These in vitro results may reflect in vivo mechanisms of idiotype suppression.

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 Enhancement of in vitro and in vivo antigen-specific antibody responses by interleukin 11.

1992 ◽  
Vol 175 (1) ◽  
pp. 211-216 ◽  
Author(s):  
T G Yin ◽  
P Schendel ◽  
Y C Yang
Keyword(s):  
T Cells ◽  
Antibody Titer ◽  
Specific Antibody ◽  
Antibody Responses ◽  
Rabbit Serum ◽  
Dependent Manner ◽  
Dose Dependent ◽  
Interleukin 11

The availability of large quantities of highly purified recombinant interleukin 11 (rhuIL-11) has allowed us to investigate the effects of rhuIL-11 on sheep red blood cell (SRBC)-specific antibody responses in the murine system. The results showed that rhuIL-11 was effective in enhancing the generation of mouse spleen SRBC-specific plaque-forming cells (PFC) in the in vitro cell culture system in a dose-dependent manner. These effects of rhuIL-11 were abrogated completely by the addition of anti-rhuIL-11 antibody, but not by the addition of preimmunized rabbit serum. Cell-depletion studies revealed that L3T4 (CD4)+ T cells, but not Lyt-2 (CD8)+ T cells, are required in the rhuIL-11-stimulated augmentation of SRBC-specific antibody responses. The effects of rhuIL-11 on the SRBC-specific antibody responses in vivo were also examined. RhuIL-11 administration to normal C3H/HeJ mice resulted in a dose-dependent increase in the number of spleen SRBC-specific PFC as well as serum SRBC-specific antibody titer in both the primary and secondary immune responses. In mice immunosuppressed by cyclophosphamide treatment, rhuIL-11 administration significantly augmented the number of spleen SRBC-specific PFC as well as serum SRBC-specific antibody titer when compared with the cyclophosphamide-treated mice without IL-11 treatment. These results demonstrated that IL-11 is a novel cytokine involved in modulating antigen-specific antibody responses in vitro as well as in vivo.

scholarly journals Antigen-specific T-cell-mediated suppression. I. Induction of L-glutamic acid(60)-L-alanine(30)-L-tyrosine(10) specific suppressor T cells in vitro requires both antigen-specific T-cell-suppressor factor and antigen

1978 ◽  
Vol 147 (1) ◽  
pp. 123-136 ◽  
Author(s):  
RN Germain ◽  
J Theze ◽  
JA Kapp ◽  
B Benacerraf
Keyword(s):  
T Cells ◽  
T Cell ◽  
Sheep Erythrocyte ◽  
Suppressor Cell ◽  
Random Copolymer ◽  
Suppressor T Cells ◽  
Suppressor Factor ◽  
Specific Suppressor T Cells

A combination of in vitro and in vivo techniques were used to explore the mode of action of both crude and purified suppressive extracts specific for the random copolymer L-giutamic acid(60)-L-alanine(30)-L-tyrosine(10) (GAT- T(s)F) obtained from nonresponder DBA/1 (H-2(q)) mice. Normal DBA/1 spleen cells were incubated under modified Mishell-Dutton culture conditions for 2 days together with crude or purified GAT-T(s)F, and in the presence or absence of free GAT. These cells were then washed extensively and 3 × 10(6) viable cells transferred to syngeneic recipients, which were challenged at the same time with the immunogenic form of GAT complexed to methylated bovine serum albumin (GAT-MBSA). GAT-specific IgG plaque-forming cells (PFC) in the spleen were assayed 7 days later. In agreement with earlier in vitro studies on the action of GAT-T(s)F, it was demonstrated that under these conditions, low concentrations of GAT-T(s)F stimulated the development of cells which, aider transfer, are able to suppress the GAT PFC response to GAT-MBSA. The cells responsible for this suppression were shown to be T lymphocytes by using nylon wool-purified T cells for suppressor cell induction and by eliminating suppressive activity in cells cultured with crude GAT-T(s)F by treatment with anti-Thy 1.2 plus C before transfer. The suppressor T cells act in a specific manner failing to suppress significantly either anti-sheep erythrocyte or trinitrophenyl-ovalbumin primary PFC responses. For the induction of GAT-specific suppressor T cells in culture, a moiety bearing H- 2(K(q) or I(q)) determinants and also GAT, either bound to the crude GAT- T(s)F or added in nanogram amounts to antigen (GAT)-free purified GAT-T(s)F, were both required.

scholarly journals Real-time analysis of T cell receptors in naive cells in vitro and in vivo reveals flexibility in synapse and signaling dynamics

2010 ◽  
Vol 207 (12) ◽  
pp. 2733-2749 ◽  
Author(s):  
Rachel S. Friedman ◽  
Peter Beemiller ◽  
Caitlin M. Sorensen ◽  
Jordan Jacobelli ◽  
Matthew F. Krummel
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Real Time ◽  
T Cell Activation ◽  
Valuable Insight ◽  
Time Dynamics ◽  
Insight Into

The real-time dynamics of the T cell receptor (TCR) reflect antigen detection and T cell signaling, providing valuable insight into the evolving events of the immune response. Despite considerable advances in studying TCR dynamics in simplified systems in vitro, live imaging of subcellular signaling complexes expressed at physiological densities in intact tissues has been challenging. In this study, we generated a transgenic mouse with a TCR fused to green fluorescent protein to provide insight into the early signaling events of the immune response. To enable imaging of TCR dynamics in naive T cells in the lymph node, we enhanced signal detection of the fluorescent TCR fusion protein and used volumetric masking with a second fluorophore to mark the T cells expressing the fluorescent TCR. These in vivo analyses and parallel experiments in vitro show minimal and transient incorporation of TCRs into a stable central supramolecular activating cluster (cSMAC) structure but strong evidence for rapid, antigen-dependent TCR internalization that was not contingent on T cell motility arrest or cSMAC formation. Short-lived antigen-independent TCR clustering was also occasionally observed. These in vivo observations demonstrate that varied TCR trafficking and cell arrest dynamics occur during early T cell activation.

scholarly journals Antigen-specific suppressor T-cell activity in genetically restricted immune spleen cells.

1978 ◽  
Vol 148 (5) ◽  
pp. 1271-1281 ◽  
Author(s):  
C W Pierce ◽  
J A Kapp
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Activity ◽  
Antibody Responses ◽  
Spleen Cells ◽  
Suppressor T Cells ◽  
Specific Suppressor T Cells ◽  
Immune Spleen Cells

Virgin spleen cells develop comparable primary antibody responses in vitro to syngeneic or allogeneic macrophages (Mphi) bearing the terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT), whereas immune spleen cells primed with syngeneic or allogeneic GAT-Mphi develop secondary responses preferentially when stimulated with GAT-Mphi syngeneic to the GAT-Mphi used for priming in vivo. These restrictions are mediated by products of the I-A subregion of the H-2 complex and are operative at the level of the GAT-Mphi-immune helper T-cell interactions. To investigate why these immune spleen cells fail to develop a significant antibody response to GAT-Mphi other than those used for in vivo immunization and determine the mechanism by which the restriction is maintained, spleen cells from virgin and syngeneic or allogeneic GAT-Mphi-primed mice were co-cultured in the presence of GAT-Mphi of various haplotypes. Antibody responses to GAT developed only in the presence of GAT-Mphi syngeneic to the Mphi used for in vivo priming; responses in cultures with GAT-Mphi allogeneic to the priming Mphi, whether these Mphi were syngeneic or allogeneic with respect to the responding spleen cells, were suppressed. The suppression was mediated by GAT-specific radiosensitive T cells. Thus, development of GAT-specific suppressor T cells appears to be a natural consequence of the immune response to GAT in responder as well as nonresponder mice. The implications of stimulation of genetically restricted immune helper T cells, and antigen-specific, but unrestricted, suppressor T cells after immunization with GAT-Mphi in vivo are discussed in the context of regulatory mechanisms in antibody responses.

Small Molecule Inhibitor of ITK Disrupts TCR Signaling and Demonstrates Anti-Tumor Efficacy

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3932-3932
Author(s):  
Mary Faris ◽  
Uriel M Malyankar ◽  
Qingping Zeng ◽  
Gary A Flynn ◽  
Gerold Feuer ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cytokine Production ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
T Cell Malignancies ◽  
Dose Dependent ◽  
Leukemias And Lymphomas

Abstract Abstract 3932 ITK (Interluekin-2 Inducible Tyrosine Kinase) is a member of the TEC family of intracellular protein tyrosine kinases. ITK is highly expressed in T cells and NK cells, with expression detected in mast cells. ITK plays a key role in several aspects of T cell biology, including T cell development, differentiation, migration, proliferation and activation. The function of ITK in immunity and allergy is well documented. T cells from ITK knock out mice show several developmental and functional defects, including defective signal transduction, altered CD4+ to CD8+ T cells ratios, reduced Th2 lineage differentiation, diminished IL4 and IL2 production and reduced T cell proliferation. Importantly ITK deficient mice fail to mount an immune response to infection and show reduced allergic asthma reactions. In contrast to its well described role in immune function, ITK's function in cancer biology is still emerging. Recent studies had reported enhanced ITK expression and activation of the ITK pathway in several types of leukemias and lymphomas. In addition, the dependence of T cell malignancies on an ITK-regulated pathway, namely the IL2/IL2R (CD25) pathway, has also been observed. Taken together, this information indicates that ITK is a therapeutic target, with applicability in leukemias and lymphomas. MannKind scientists have developed a series of selective small molecule ITK inhibitors, including the orally available tool compound described within, and evaluated their activity in enzyme, cell-based and in vivo studies. In cellular assays, the compounds showed significant inhibition of the T cell-receptor mediated activation of the ITK pathways and related downstream cytokine production. In addition to inhibiting the phosphorylation of ITK and its downstream mediator, PLCg, our tool compounds inhibited the production of IL2 and expression of CD25 in a dose dependent manner. Importantly, our compound regulated the in vitro growth of tumor T cells but not that of unrelated control cells. In vivo studies revealed that the tool compounds inhibited the growth and progression of patient derived ATL tumors in a xenograft pre-clinical model, and prolonged the survival of treated mice in a dose dependent manner, in addition to regulating cytokine production in vivo. In summary, our team has identified ITK selective compounds with demonstrated on-target and anti-tumor activity in vitro and preclinical T cell tumor models, and validated this pathway relative to T cell malignancies. This effort provides a platform for further compound optimization and evaluation for hematologic malignancies. Disclosures: Faris: MannKind Corp: Employment. Malyankar:MannKind Corp: Employment. Zeng:MannKind Corp: Employment. Kertesz:Mannkind Corporation: Employment, Equity Ownership. Vuga:MannKind Corp.: Employment. Rosario:MannKind Corp: Employment. Bot:MannKind Corp: Employment.

Strong CD28 Costimulation Suppresses Induction of Regulatory T Cells From Naïve Precursors through Lck Signaling.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3728-3728
Author(s):  
Kenrick Semple ◽  
Antony Nguyen ◽  
Yu Yu ◽  
Claudio Anasetti ◽  
Xue-Zhong Yu
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Conflicts Of Interest ◽  
Graft Versus Host ◽  
Cell Immunity ◽  
Cd28 Costimulation ◽  
Insight Into

Abstract Abstract 3728 CD28 costimulation is required for the generation of naturally-derived regulatory T cells (nTregs) in the thymus through Lck-signaling. However, it is not clear how CD28 costimulation regulates the generation of induced Tregs (iTregs) from naïve CD4 T-cell precursors in the periphery. To address this question, we induced iTregs (CD25+Foxp3+) from naïve CD4 T cells (CD25−Foxp3−) by TCR-stimulation with additional TGFβ in vitro, and found that the generation of iTregs was inversely related to the level of CD28 costimulation independently of IL-2. By using a series of transgenic mice on CD28-deficient background that bears WT CD28 or mutated CD28 in its cytosolic tail incapable of binding to Lck, PI3K or Itk, we found that CD28-mediated Lck-signaling plays an essential role in the suppression of iTreg generation under strong CD28 costimulation. Furthermore, we demonstrate that T cells with the CD28 receptor incapable of activating Lck were prone to iTreg induction in vivo, which contributed to their reduced ability to cause graft-versus-host disease. These findings reveal a novel mechanistic insight into how CD28 costimulation negatively regulates the generation of iTregs, and provide the rationale for promoting T-cell immunity or tolerance by regulating Tregs through targeting CD28-signaling. Disclosures: No relevant conflicts of interest to declare.

scholarly journals In vitro alteration of receptors for vasoactive intestinal peptide changes the in vivo localization of mouse T cells.

1984 ◽  
Vol 160 (4) ◽  
pp. 1054-1069 ◽  
Author(s):  
C A Ottaway
Keyword(s):  
T Cells ◽  
Vasoactive Intestinal Peptide ◽  
Receptor Expression ◽  
Peyer's Patches ◽  
Peyer’S Patches ◽  
Mesenteric Lymph Nodes ◽  
Dose Dependent Decrease ◽  
Dose Dependent

The capacity of T lymphocytes exposed in vitro to the neuropeptide vasoactive intestinal peptide (VIP) to bind VIP in vitro and to migrate to different tissues in vivo has been studied. VIP treatment of T cells resulted in a time- and dose-dependent loss of the ability of T cells to specifically bind radioiodinated VIP. Altered binding was due to a decrease in the expression of cellular receptors for VIP on the treated cells rather than an alteration in the affinity of the cells for the neuropeptide. Alteration of VIP receptor expression was not associated with a change in the expression of Thy-1, Lyt-1, or Lyt-2 surface markers by the treated cells. VIP treatment of T cells in vitro resulted, however, in a dose-dependent decrease in the ability of the treated cells to localize in mesenteric lymph nodes (MLN) and Peyer's patches of recipient animals at early times after cell transfer, and this was due to a selective decrease in the rate of accumulation of the treated cells in these tissues. There was no alteration in the distribution of VIP-treated cells in the blood, spleen, liver, or other major organs of the recipient animals. It is concluded that the presence of VIP receptors on T cells facilitates the entry of T cells into MLN and Peyer's patches in vivo, and it is proposed that this effect is mediated by T cell-VIP interactions in the vicinity of the specialized endothelium of those tissues.

Heparin Induces Synthesis and Secretion of Tissue Factor Pathway Inhibitor from Endothelial Cells In Vitro

2000 ◽  
Vol 83 (06) ◽  
pp. 937-943 ◽  
Author(s):  
Birgit Svensson ◽  
Randi Olsen ◽  
Mirella Ezban ◽  
Bjarne Østerud ◽  
Ruth Paulssen ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Surface Membrane ◽  
Molecular Size ◽  
Fold Increase ◽  
Coagulation System ◽  
Dose Dependent Increase ◽  
Dose Dependent ◽  
Stimulation Of

SummaryTFPI is a potent inhibitor of the extrinsic coagulation system constitutively synthesized by endothelial cells. A major portion of intravascular TFPI is stored associated with endothelial cells, and administration of unfractionated heparin (UFH) in vivo causes a prompt mobilization of TFPI into the circulation. The present study was conducted to investigate how UFH affected the synthesis, secretion and anticoagulant potency of TFPI in endothelial cells in vitro. A spontaneously transformed immortal endothelial cell line was used (ECV304). Stimulation of ECV304 cells with UFH caused a prompt dose-dependent (0-5 IU UFH/ml) release of TFPI to the medium accompanied by no change of TFPI at the surface membrane assessed by immunocytochemical methods. Northern blot analysis revealed two mRNA transcripts for TFPI with a molecular size of 1.4 kb and 4.4 kb, respectively. Stimulation of ECV304 cells for 24 hrs with various concentrations of UFH caused a dose-dependent increase of TFPI in the medium (6.2-29.6 ng/106 cells within the concentration range 0-10 IU/ml). A similar dose-dependent increase in the expression of both TFPI mRNA species was observed. Long-term incubation of ECV304 cells with 5.0 IU/ml UFH caused a 5-10 fold increase in the TFPI concentration accumulated in the medium over 48 hrs. The increased TFPI mRNA expression induced by UFH appeared already after 10 min, peaked after 2-4 hrs, remained augmented throughout the entire period of UFH exposure, and preceeded the synthesis-dependent increase in TFPI release by 2-4 hrs. The procoagulant activity of the cells was downregulated by 36 % and the contribution of TFPI to the anticoagulant potency of ECV304 cells was moderately increased after 24 hrs heparin stimulation. It is suggested that these mechanisms are of major importance for the anticoagulant function of heparins.

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