scholarly journals The novel chelator lipid 3(nitrilotriacetic acid)-ditetradecylamine (NTA3-DTDA) promotes stable binding of His-tagged proteins to liposomal membranes: Potent anti-tumor responses induced by simultaneously targeting antigen, cytokine and costimulatory signals to T cells

2005 ◽  
Vol 1716 (2) ◽  
pp. 104-116 ◽  
Author(s):  
Christina L. van Broekhoven ◽  
Joseph G. Altin
Keyword(s):  
T Cells ◽  
Nitrilotriacetic Acid ◽  
The Novel ◽  
Liposomal Membranes ◽  
Costimulatory Signals

GM-CSF and IL-2 share common control mechanisms in response to costimulatory signals in T cells

1995 ◽  
Vol 57 (5) ◽  
pp. 767-773 ◽  
Author(s):  
M. Frances Shannon ◽  
S. Roy Himes ◽  
Leeanne S. Coles
Keyword(s):  
T Cells ◽  
Control Mechanisms ◽  
Gm Csf ◽  
Common Control ◽  
Costimulatory Signals

scholarly journals Evidence for an additional ligand, distinct from B7, for the CTLA-4 receptor

1993 ◽  
Vol 90 (23) ◽  
pp. 11182-11186 ◽  
Author(s):  
Z Razi-Wolf ◽  
F Galvin ◽  
G Gray ◽  
H Reiser
Keyword(s):  
T Cells ◽  
Costimulatory Molecule ◽  
Fluorescein Isothiocyanate ◽  
Histocompatibility Complex ◽  
Additional Ligand ◽  
Soluble Fusion Protein ◽  
Costimulatory Signals ◽  
Antigen Presenting ◽  
Allogeneic Stimulation ◽  
Better Than

Activation of T lymphocytes requires the recognition of peptide-major histocompatibility complex complexes and costimulatory signals provided by antigen-presenting cells (APCs). The best-characterized costimulatory molecule to date is the B7 antigen, a member of the immunoglobulin family that binds two receptors, CD28 and CTLA-4, expressed on the T-cell surface. Using the anti-mouse B7 (mB7) monoclonal antibody (mAb) 16-10A1, which we recently developed, we found that mB7 is indeed an important costimulatory ligand for the antigen-specific activation of murine T cells by B lymphocytes. Three lines of evidence suggest, however, the existence of at least one additional ligand for the CTLA-4 receptor. First, a soluble fusion protein of human CTLA-4 and the IgG1 Fc region, termed CTLA4Ig, blocks better than the anti-mB7 mAb the allogeneic stimulation of T cells by unfractionated splenic APCs. Second, saturating amounts of anti-mB7 mAb do not significantly block binding of fluorescein isothiocyanate-conjugated CTLA4Ig to activated splenic APCs. Furthermore, CTLA4Ig but not the anti-mB7 mAb reacts with the M12 and M12.C3 cell lines. The identification of an additional ligand for CTLA-4 may have applications to the treatment of autoimmune disease and transplant-associated disorders.

scholarly journals Rapamycin alleviates inflammation and muscle weakness, while altering the Treg/Th17 balance in a rat model of myasthenia gravis

2017 ◽  
Vol 37 (4) ◽  
Author(s):  
Feng Jing ◽  
Fei Yang ◽  
Fang Cui ◽  
Zhaohui Chen ◽  
Li Ling ◽  
...  
Keyword(s):  
T Cells ◽  
Autoimmune Disease ◽  
Myasthenia Gravis ◽  
Rat Model ◽  
Th17 Cells ◽  
Mortality Rates ◽  
The Novel ◽  
Muscular Weakness ◽  
Body Weights ◽  
Experimental Autoimmune

Myasthenia gravis (MG) is an autoimmune disease commonly treated with immunosuppressants. We evaluated the novel immunosuppressant, rapamycin (RAPA), in a rat model of experimental autoimmune MG (EAMG). Mortality rates in the RAPA (12%) were significantly down compared with the EAMG (88%) or cyclophosphamide (CTX) (68%) intervention groups. Muscular weakness decreased after both RAPA and CTX treatment. However, Lennon scores were lower (1.74 ± 0.49, 3.39 ± 0.21, and 3.81 ± 0.22 in RAPA, CTX, and EAMG groups, respectively), and body weights (203.12 ± 4.13 g, 179.23 ± 2.13 g, and 180.13 ± 5.13 g in RAPA, CTX, and EAMG groups, respectively) were significantly higher, only in the RAPA group. The proportion of regulatory T cells (Treg) significantly increased, while that of Th17 cells significantly decreased in the RAPA group compared with the EAMG group. In comparison, CTX intervention resulted in increased Th17 but significantly decreased Tregs. Hence, RAPA can be more effectively used in comparison with CTX to treat MG, with an efficacy higher than that of CTX. In addition, our results suggest RAPA’s efficacy in alleviating symptoms of MG stems from its ability to correct the Treg/Th17 imbalance observed in MG.

scholarly journals CD28 and CTLA-4 have opposing effects on the response of T cells to stimulation.

1995 ◽  
Vol 182 (2) ◽  
pp. 459-465 ◽  
Author(s):  
M F Krummel ◽  
J P Allison
Keyword(s):  
T Cells ◽  
T Cell ◽  
Costimulatory Molecule ◽  
Surface Glycoprotein ◽  
T Cell Proliferation ◽  
Cell Surface Glycoprotein ◽  
Costimulatory Signals ◽  
Low Levels ◽  
Opposing Effects ◽  
Antigen Presenting

The importance of the B7/CD28/CTLA-4 molecules has been established in studies of antigen-presenting cell-derived B7 and its interaction with the T cell costimulatory molecule CD28. CTLA-4, a T cell surface glycoprotein that is related to CD28, can also interact with B7-1 and B7-2. However, less is known about the function of CTLA-4, which is expressed at highest levels after activation. We have generated an antibody to CTLA-4 to investigate the consequences of engagement of this molecule in a carefully defined system using highly purified T cells. We show here that the presence of low levels of B7-2 on freshly explanted T cells can partially inhibit T cell proliferation, and this inhibition is mediated by interactions with CTLA-4. Cross-linking of CTLA-4 together with the TCR and CD28 strongly inhibits proliferation and IL-2 secretion by T cells. Finally, results show that CD28 and CTLA-4 deliver opposing signals that appear to be integrated by the T cell in determining the response to activation. These data strongly suggest that the outcome of T cell antigen receptor stimulation is regulated by CD28 costimulatory signals, as well as inhibitory signals derived from CTLA-4.

scholarly journals Whole blood immunophenotyping uncovers immature neutrophil-to-VD2 T-cell ratio as an early marker for severe COVID-19

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Guillaume Carissimo ◽  
Weili Xu ◽  
Immanuel Kwok ◽  
Mohammad Yazid Abdad ◽  
Yi-Hao Chan ◽  
...  
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Whole Blood ◽  
Roc Analysis ◽  
Γδ T Cells ◽  
High Sensitivity ◽  
The Novel ◽  
Cellular Mechanisms ◽  
Cell Counts ◽  
Novel Coronavirus

Abstract SARS-CoV-2 is the novel coronavirus responsible for the current COVID-19 pandemic. Severe complications are observed only in a small proportion of infected patients but the cellular mechanisms underlying this progression are still unknown. Comprehensive flow cytometry of whole blood samples from 54 COVID-19 patients reveals a dramatic increase in the number of immature neutrophils. This increase strongly correlates with disease severity and is associated with elevated IL-6 and IP-10 levels, two key players in the cytokine storm. The most pronounced decrease in cell counts is observed for CD8 T-cells and VD2 γδ T-cells, which both exhibit increased differentiation and activation. ROC analysis reveals that the count ratio of immature neutrophils to VD2 (or CD8) T-cells predicts pneumonia onset (0.9071) as well as hypoxia onset (0.8908) with high sensitivity and specificity. It would thus be a useful prognostic marker for preventive patient management and improved healthcare resource management.

scholarly journals Differential effects of anti-B7-1 and anti-B7-2 monoclonal antibody treatment on the development of diabetes in the nonobese diabetic mouse.

1995 ◽  
Vol 181 (3) ◽  
pp. 1145-1155 ◽  
Author(s):  
D J Lenschow ◽  
S C Ho ◽  
H Sattar ◽  
L Rhee ◽  
G Gray ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
T Cells ◽  
Autoimmune Diabetes ◽  
Disease Process ◽  
Nod Mice ◽  
Dependent Diabetes Mellitus ◽  
Antibody Treatment ◽  
Treatment Groups ◽  
Nonobese Diabetic ◽  
Costimulatory Signals

Insulin-dependent diabetes mellitus (IDDM) is thought to be an immunologically mediated disease resulting in the complete destruction of the insulin-producing islets of Langerhans. It has become increasingly clear that autoreactive T cells play a major role in the development and progression of this disease. In this study, we examined the role of the CD28/B7 costimulation pathway in the development and progression of autoimmune diabetes in the nonobese diabetic (NOD) mouse model. Female NOD mice treated at the onset of insulitis (2-4 wk of age) with CTLA4Ig immunoglobulin (Ig) (a soluble CD28 antagonist) or a monoclonal antibody (mAb) specific for B7-2 (a CD28 ligand) did not develop diabetes. However, neither of these treatments altered the disease process when administered late, at > 10 wk of age. Histological examination of islets from the various treatment groups showed that while CTLA4Ig and anti-B7-2 mAb treatment blocked the development of diabetes, these reagents had little effect on the development or severity of insulitis. Together these results suggest that blockade of costimulatory signals by CTLA4Ig or anti-B7-2 acts early in disease development, after insulitis but before the onset of frank diabetes. NOD mice were also treated with mAbs to another CD28 ligand, B7-1. In contrast to the previous results, the anti-B7-1 treatment significantly accelerated the development of disease in female mice and, most interestingly, induced diabetes in normally resistant male mice. A combination of anti-B7-1 and anti-B7-2 mAbs also resulted in an accelerated onset of diabetes, similar to that observed with anti-B7-1 mAb treatment alone, suggesting that anti-B7-1 mAb's effect was dominant. Furthermore, treatment with anti-B7-1 mAbs resulted in a more rapid and severe infiltrate. Finally, T cells isolated from the pancreas of these anti-B7-1-treated animals exhibited a more activated phenotype than T cells isolated from any of the other treatment groups. These studies demonstrate that costimulatory signals play an important role in the autoimmune process, and that different members of the B7 family have distinct regulatory functions during the development of autoimmune diabetes.

scholarly journals Different structural constraints for recognition of mouse H-2Kd and -Kk antigens by alloimmune cytolytic T lymphocytes.

1986 ◽  
Vol 164 (6) ◽  
pp. 1823-1834 ◽  
Author(s):  
J Schøller ◽  
R Shimonkevitz ◽  
H R MacDonald ◽  
S Kvist
Keyword(s):  
T Cells ◽  
Amino Acid ◽  
T Lymphocytes ◽  
Surface Expression ◽  
Cell Surface Expression ◽  
Structural Constraints ◽  
The Novel ◽  
Different Types ◽  
Target Molecules ◽  
Hybrid Genes

We have constructed a new series of hybrid genes among the H-2Kd,-Kk, and -Kb. The site of recombination occurs in the third exon, encoding the alpha 2 domain, and divides this domain into two parts, alpha 2A and alpha 2B. The novel genes differ only in the COOH-terminal half of the alpha 2 domain, i.e., the alpha 2B region. This region, comprising residues 142-182, contains a limited number of amino acid differences between the three alleles. The hybrid genes have been introduced into 1T 22-6 cells (H-2q), and cell surface expression of hybrid antigens was verified. Cells expressing different types of hybrid antigens have been examined for their susceptibility to lysis by cytotoxic T lymphocytes directed either against the H-2Kd antigen or the H-2Kk antigen. Our results show that the alpha 1 and alpha 2A domains of the H-2Kk antigen can constitute target molecules for alloimmune anti-Kk T cells, whereas the alpha 2B region, when exchanged for Kd or Kb sequences, plays only a limited role. In contrast, the alpha 1 and alpha 2A domains of Kd are not sufficient to be recognized by alloimmune anti-Kd T cells. In this instance, the alpha 2B domain seems to play an essential role. This region has undergone several amino acid substitutions involving charged residues.

scholarly journals Modulation of Kv Channel Expression and Function by TCR and Costimulatory Signals during Peripheral CD4+ Lymphocyte Differentiation

2002 ◽  
Vol 196 (7) ◽  
pp. 897-909 ◽  
Author(s):  
Qing-Hua Liu ◽  
Bernd K. Fleischmann ◽  
Brian Hondowicz ◽  
Curtis C. Maier ◽  
Laurence A. Turka ◽  
...  
Keyword(s):  
T Cells ◽  
Signaling Pathways ◽  
T Cell Activation ◽  
Cell Activation ◽  
Effector Cells ◽  
Kv Channel ◽  
Kv Channels ◽  
Costimulatory Signals ◽  
Cd4 Lymphocyte ◽  
Cd4 Lymphocytes

Ionic signaling pathways, including voltage-dependent potassium (Kv) channels, are instrumental in antigen-mediated responses of peripheral T cells. However, how Kv channels cooperate with other signaling pathways involved in T cell activation and differentiation is unknown. We report that multiple Kv channels are expressed by naive CD4+ lymphocytes, and that the current amplitude and kinetics are modulated by antigen receptor–mediated stimulation and costimulatory signals. Currents expressed in naive CD4+ lymphocytes are consistent with Kv1.1, Kv1.2, Kv1.3, and Kv1.6. Effector CD4+ cells generated by optimal TCR and costimulation exhibit only Kv1.3 current, but at approximately sixfold higher levels than naive cells. CD4+ lymphocytes anergized through partial stimulation exhibit similar Kv1.1, Kv1.2, and/or Kv1.6 currents, but approximately threefold more Kv1.3 current than naive cells. To determine if Kv channels contribute to the distinct functions of naive, effector, and anergized T cells, we tested their role in immunoregulatory cytokine production. Each Kv channel is required for maximal IL-2 production by naive CD4+ lymphocytes, whereas none appears to play a role in IL-2, IL-4, or IFN-γ production by effector cells. Interestingly, Kv channels in anergized lymphocytes actively suppress IL-4 production, and these functions are consistent with a role in regulating the membrane potential and calcium signaling.

scholarly journals Priming of T cells to Fas-mediated proliferative signals by interleukin-7

Blood ◽  
2008 ◽  
Vol 112 (4) ◽  
pp. 1195-1204 ◽  
Author(s):  
Bence Rethi ◽  
Nancy Vivar ◽  
Stefano Sammicheli ◽  
Caroline Fluur ◽  
Nicolas Ruffin ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocyte ◽  
Cell Receptor ◽  
Cell Depletion ◽  
Activated T Cells ◽  
T Cell Depletion ◽  
Interleukin 7 ◽  
Costimulatory Signals ◽  
Opposing Effects

Abstract T-cell depletion associated with HIV infection or cytoreductive therapies triggers potential T-cell regenerative mechanisms such as peripheral T-lymphocyte expansion to weak antigenic stimuli and the increased availability of interleukin-7 (IL-7), a cytokine with potent antiapoptotic and proliferative activities. Deleterious mechanisms also associated with lymphopenia, such as increased Fas expression and apoptosis of T cell, however, may result in opposing effects. In this study, we show that Fas molecules, primarily associated with T-cell depletion in lymphopenic settings, may also contribute to compensatory T-cell expansion through transmitting costimulatory signals to suboptimally activated T cells. Proliferation of T lymphocytes in response to concomitant Fas and T-cell receptor (TCR) triggering was shown to be increased in HIV-infected individuals compared with noninfected controls. As IL-7 levels are often elevated in lymphopenic individuals in association with increased Fas expression, we analyzed whether IL-7 would influence Fas-mediated proliferative signals in T cells. We show that IL-7 is able to increase the efficacy of Fas to induce proliferation of suboptimally activated T cells. Thus, high IL-7 levels associated with lymphopenic conditions may simultaneously induce sensitivity to Fas-mediated apoptosis in nonactivated T cells and increase Fas-induced costimulatory signals in T cells recognizing low-affinity antigens.

Sign in / Sign up

Export Citation Format

Share Document