The Expression of CD28 and Its Synergism on the Immune Response of Flounder (Paralichthys olivaceus) to Thymus-Dependent Antigen

CD28 is well known as a critical T-cell costimulatory receptor involved in T cell activation by binding to its ligands. In this study, CD28 was cloned, and its expression profiles were characterized in flounder (Paralichthys olivaceus); variations of CD28+ cells after being stimulated with different types of antigens and the function of the CD28 costimulatory pathway on T-cell activation were investigated in vitro. fCD28 consists of four exons and three introns, and the full-length cDNA of fCD28 was 675-bp encoded 224 amino acids. The conserved motif (121TFPPPF126) binding to the CD80/86 ligand exists in the Ig-superfamily homology domain. The high expression of fCD28 is in gills, PBLs, head kidney, and spleen. CD28+ cells were co-localized with CD4+ T lymphocytes but not on IgM+ B lymphocyte cells. Moreover, the expression of CD28 was significantly varied in flounder after being stimulated by keyhole limpet hemocyanin (KLH) at both the transcriptional and cellular levels, while no significant differences were observed between lipopolysaccharide (LPS) stimulation and the control group. Notably, treatment of PBLs cultured in vitro with CD28 molecule-specific antibody (anti-CD28 Abs) and PHA produced more cell colonies and stimulated the proliferation of cultured leukocytes compared to PHA stimulation alone and the control group, and a higher level of IL-2 was detected in the culture medium. Meanwhile, anti-CD28 Abs increased the percent of CD28+ cells (10.41 ± 1.35%), CD4+ T lymphocytes (18.32 ± 2.15%), and CD28+/CD4+ double-positive cells (6.24 ± 1.52%). This effect also resulted in significant variations in the genes of cell membrane-bound molecules, cytokines, and related signaling pathways in cultured leukocytes, with significant changes in the genes of interleukin-2 (IL-2) and nuclear factor of activated T cells (NFAT) in the early stages of culture, and the expression of other molecules increased over time. These results proved the localization of the CD28 molecule on T lymphocytes in flounder, and anti-CD28 may act as the B7 ligand involved in T cell activation after antigen stimulation. These data provide a basis for a more in-depth study of the mechanism of the CD28 costimulatory pathway in T cell activation.

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Immune function of the blood-brain barrier: incomplete presentation of protein (auto-)antigens by rat brain microvascular endothelium in vitro.

The Journal of Cell Biology ◽

10.1083/jcb.110.5.1757 ◽

1990 ◽

Vol 110 (5) ◽

pp. 1757-1766 ◽

Cited By ~ 100

Author(s):

W Risau ◽

B Engelhardt ◽

H Wekerle

Keyword(s):

T Cells ◽

Endothelial Cells ◽

T Cell ◽

T Lymphocytes ◽

Rat Brain ◽

Blood Brain Barrier ◽

T Cell Activation ◽

Cell Activation ◽

Ifn Gamma

The endothelial blood-brain barrier (BBB) has a critical role in controlling lymphocyte traffic into the central nervous system (CNS), both in physiological immunosurveillance, and in its pathological aberrations. The intercellular signals that possibly could induce lymphocytes to cross the BBB include immunogenic presentation of protein (auto-)antigens by BBB endothelia to circulating T lymphocytes. This concept has raised much, though controversial, attention. We approached this problem by analyzing in vitro immunospecific interactions between clonal rat T lymphocyte lines with syngeneic, stringently purified endothelial monolayer cultures from adult brain micro-vessels. The rat brain endothelia (RBE) were established from rat brain capillaries using double collagenase digestion, density gradient fractionation and selective cytolysis of contaminating pericytes by anti-Thy 1.1 antibodies and complement. Incubation with interferon-gamma in most of the brain-derived endothelial cells induced Ia-antigens in the cytoplasm and on the cell surface in some of the cells. Before the treatment, the cells were completely Ia-negative. Pericytes were unresponsive to IFN-gamma treatment. When confronted with syngeneic T cell lines specific for protein (auto-)antigens (e.g., ovalbumin and myelin basic protein, MBP), RBE were completely unable to induce antigen-specific proliferation of syngeneic T lymphocytes irrespective of pretreatment with IFN-gamma and of cell density. RBE were inert towards the T cells, and did not suppress T cell activation induced by other "professional" antigen presenting cells (APC) such as thymus-derived dendritic cells or macrophages. IFN-gamma-treated RBE were, however, susceptible to immunospecific T cell killing. They were lysed by MBP-specific T cells in the presence of the specific antigen or Con A. Antigen dependent lysis was restricted by the appropriate (MHC) class II product. We conclude that the interaction of brain endothelial cells with encephalitogenic T lymphocytes may involve recognition of antigen in the molecular context of relevant MHC products, but that this interaction per se is insufficient to initiate the full T cell activation program.

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Platelets from Patients with Myocardial Infarction Can Activate T Cells in Vitro

Blood ◽

10.1182/blood.v126.23.3448.3448 ◽

2015 ◽

Vol 126 (23) ◽

pp. 3448-3448 ◽

Cited By ~ 1

Author(s):

Elena E. Solomou ◽

Vasilios Gizas ◽

Theodora Babali ◽

Angelos Perperis ◽

Evgenia Verigou ◽

...

Keyword(s):

Myocardial Infarction ◽

T Cells ◽

T Cell ◽

Unstable Angina ◽

T Cell Activation ◽

Healthy Subjects ◽

Cell Activation ◽

Control Group ◽

Healthy Controls

Abstract Specific aim: Our aim was to examine whether T cells can be activated by the circulating activated platelets from patients with myocardial infarction (with ST elevation-STEMI) Methods: After written informed consent was obtained, peripheral blood mononuclear cells (PBMCs) were isolated from heparinized venous blood obtained from 20 patients with STEMI (18 men and 2 women) at the time of hospital admission at diagnosis, before receiving any treatment, as well as 5 days and 30 days later. We also analyzed 10 healthy subjects (8 men and 2 women), and 5 patients with unstable angina who served as the disease control group. PBMCs were analyzed by flow cytometry with the following markers and their isotypic controls: CD4, CD25, CD69, and FOXP3. We also isolated platelet rich plasma or plasma alone from the patients and the healthy subjects, and used in mixed cultures with PBMCs. Results: We first examined T cell activation by measuring CD69 expression on CD4 T cells following incubation with platelets obtained from patients with STEMI. T cells treated with platelets from patients with STEMI showed increased expression of CD69 (as an activation marker) compared with T cells treated with platelets from healthy subjects (p<0.05, Figure 1). There was no T cell activation following incubation with plasma alone from patients or healthy controls. We then examined the percentages of CD4+CD25+hi (regulatory T cells). There was no statistical difference in Tregs between patients at presentation and controls (healthy subjects and disease control group). Five days later, patients with STEMI displayed increased levels of Tregs compared with the 2 control groups; one month later, Treg numbers returned to the initial presentation levels (p<0.05, Figure 2) Conclusion: To our knowledge we describe for the first time that platelets from patients with STEMI can activate T cells in vitro. In patients with STEMI, an increase in Tregs possibly in an effort to suppress immune system activation secondary to platelet activation, appears shortly after the infarct and normalizes a month later. Figure 1. T cell activation after treatment with platelets from patients with STEMI compared with the platelets from healthy controls or plasma alone Figure 1. T cell activation after treatment with platelets from patients with STEMI compared with the platelets from healthy controls or plasma alone Figure 2. Increased T regs in patients with STEMI , 5 days after admission (STEMI EXIT) ( UA;unstable angina, STEMI 1mfup; STEMI after one month) Figure 2. Increased T regs in patients with STEMI , 5 days after admission (STEMI EXIT) ( UA;unstable angina, STEMI 1mfup; STEMI after one month) Disclosures No relevant conflicts of interest to declare.

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T-cell redirected killing and cure of pancreatic and gastric cancer xenografts by targeting Trop-2.

Journal of Clinical Oncology ◽

10.1200/jco.2015.33.3_suppl.262 ◽

2015 ◽

Vol 33 (3_suppl) ◽

pp. 262-262

Author(s):

David M. Goldenberg ◽

Edmund A. Rossi ◽

Diane L Rossi ◽

Thomas M. Cardillo ◽

Chien-Hsing Chang

Keyword(s):

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Ex Vivo ◽

Control Group ◽

Calcium Signal ◽

Target Cells ◽

Normal Tissues

262 Background: Trop-2 [also called tumor-associated calcium signal transducer 2 (TACSTD2), EGP-1 (epithelial glycoprotein-1), GA733-1, or M1S1]is a 35 kDa transmembrane glycoprotein that is overexpressed relative to normal tissues in a variety of human cancers, including pancreatic and gastric carcinomas, where increased expression correlates with poor prognosis. Trop-2 appears to be more tumor-specific than the related molecule, EpCAM (Trop-1). MT110, the EpCAM antibody x CD3 bispecific T-cell engager (BiTE), is currently undergoing a Phase I study in various solid tumors, including lung, gastric, colorectal, breast, prostate, and ovarian cancers. We produced a similar T-cell redirecting bispecific tandem scFv, E1-3, using the variable domains of hRS7 (humanized anti-Trop-2 mAb) and Okt-3 (anti-CD3 mAb). Methods: T-cell activation, cytokine induction and cytotoxicity were evaluated ex vivo using PBMCs or purified T cells with human pancreatic (Capan-1 and BxPC3) and gastric (NCI-N87) cancer cell lines as target cells. In vivo activity was assayed with NCI-N87 xenografts that were inoculated s.c. in a mixture with twice the number of human PBMCs and matrigel. Results: In the presence of target cells and PBMCs, E1-3 potently induced T-cell activation, proliferation, and dose-dependent cytokine production of IL-2 (>2 ng/mL), IL-6 (>1 ng/mL), IL-10 (>7 ng/mL), TNF-α (>1 ng/mL) and IFN-γ (>50 ng/mL). In vitro, E1-3 mediated a highly potent T-cell lysis of BxPC3 [IC50=0.09(±0.04) pM], Capan-1 [IC50=1.2(±1.1) pM] and NCI-N87 [IC50=1.2(±1.2) pM] target cells. In vivo, two 50-µg doses of E1-3 given three days apart cured all of the mice (N=8) bearing NCI-N87 xenografts (P=0.0005; Log-Rank). Tumors in the control group (PBMCs only) reached the endpoint (TV>1 cm3) with a median of 39.5 days. All mice remained tumor-free in the E1-3 group at 78 days. Conclusions: Trop-2 is an attractive target for T-cell-mediated killing of pancreatic, gastric and other epithelial cancers.

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Differential Leukocyte miRNA Responses Following Pan T Cell, Allorecognition and Allosecretome-Based Therapeutics Activation

10.21203/rs.2.18715/v1 ◽

2019 ◽

Author(s):

Xining Yang ◽

Wendy M. Toyofuku ◽

Mark D. Scott

Keyword(s):

T Cell ◽

Autoimmune Diseases ◽

T Cell Activation ◽

Mirna Expression ◽

Cell Activation ◽

Expression Profiles ◽

Immunomodulatory Activity ◽

Mirna Expression Profiles

Abstract Background: Effective immunomodulation of T cell responses is critical in treating both autoimmune diseases and cancer. Our previous studies have demonstrated that nanoscale bioengineering of cell surfaces with methoxypolyethylene glycol (mPEG) induces a potent tolerogenic immunomodulatory effect. Moreover, secretomes derived from mPEG- or control mixed lymphocyte alloactivation assays also exerted potent immunomodulatory activity that was mediated by microRNAs (miRNA). In this study, the immunomodulatory effects of Pan T cell activators (PHA and anti-CD3/CD28), alloactivation (MHC-disparate donors; ± mPEG grafting) and biomanufactured miRNA-based allo-secretome therapeutics (SYN, TA1, IA1 and IA2) were examined on T cell proliferation, subset differentiation and leukocyte miRNA expression profiles of resting human PBMC. Results: In contrast to Pan T cell activation, allorecognition and the pro-inflammatory IA1 secretome product induced increasingly controlled proliferation of resting PBMC. The differential effects of the activation strategies were also apparent in T cell differentiation and the Teff:Treg ratio and in the miRNA expression profiles noted in the treated PBMC. In contrast, the mPEG-PBMC and TA1 secretome products inhibited alloproliferation. Importantly, the activation strategies exerted significantly different miRNA expression in the treated leukocytes that was associated with differences in proliferation and cellular differentiation. Conclusions: Immunomodulatory secretome-derived, miRNA-enriched, therapeutics can be reproducibly biomanufactured that will induce the specific bioregulatory events necessary to induce the differentiation of naïve T cells to produce a tolerogeneic (TA1) or inflammatory (IA1) response both in vitro and in vivo. The successful development and biomanufacturing of immunomodulatory, miRNA-enriched, secretome biotherapeutics may provide potent tools for the systemic treatment of autoimmune diseases or enhancing the endogenous immune response to cancer while reducing the potential adverse risks of more non-specific immunomodulatory approaches.

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CD28 interaction with B7 costimulates primary allogeneic proliferative responses and cytotoxicity mediated by small, resting T lymphocytes.

Journal of Experimental Medicine ◽

10.1084/jem.175.2.353 ◽

1992 ◽

Vol 175 (2) ◽

pp. 353-360 ◽

Cited By ~ 224

Author(s):

M Azuma ◽

M Cayabyab ◽

D Buck ◽

J H Phillips ◽

L L Lanier

Keyword(s):

T Cells ◽

T Cell ◽

T Lymphocytes ◽

T Cell Activation ◽

Proliferative Response ◽

Cell Activation ◽

B Cell Activation ◽

Rapid Responses ◽

Cell Clones

Engagement of the CD3/T cell antigen receptor complex on small, resting T cells is insufficient to trigger cell-mediated cytotoxicity or to induce a proliferative response. In the present study, we have used genetic transfection to demonstrate that interaction of the B7-BB1 B cell activation antigen with the CD28 T cell differentiation antigen costimulates cell-mediated cytotoxicity and proliferation initiated by either anti-CD2 or anti-CD3 monoclonal antibody (mAb). Moreover, a B7-negative Burkitt's lymphoma cell line that fails to stimulate an allogeneic mixed lymphocyte response is rendered a potent stimulator after transfection with B7. The mixed leukocyte reaction proliferative response against the B7 transfectant is inhibited by either anti-CD28 or B7 mAb. We also demonstrate that freshly isolated small, resting human T cells can mediate anti-CD3 or anti-CD2 mAb-redirected cytotoxicity against a murine Fc receptor-bearing mastocytoma transfected with human B7. These preexisting cytotoxic T lymphocytes in peripheral blood are present in both the CD4 and CD8 subsets, but are preferentially within the CD45RO+ "memory" population. While small, resting T cells apparently require costimulation by CD28/B7 interactions, this requirement is lost after T cell activation. Anti-CD3 initiates a cytotoxic response mediated by in vitro cultured T cell clones in the absence of B7 ligand. The existence of functional cytolytic T cells in the small, resting T cell population may be advantageous in facilitating rapid responses to immune challenge.

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Voriconazole Inhibits Fungal Growth without Impairing Antigen Presentation or T-Cell Activation

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.6.1818-1823.2003 ◽

2003 ◽

Vol 47 (6) ◽

pp. 1818-1823 ◽

Cited By ~ 11

Author(s):

Heather L. Van Epps ◽

Marta Feldmesser ◽

Eric G. Pamer

Keyword(s):

T Cells ◽

T Cell ◽

T Lymphocytes ◽

Animal Models ◽

T Cell Activation ◽

Cell Activation ◽

Fungal Growth ◽

Antifungal Drugs ◽

Isolation And Characterization

ABSTRACT Invasive aspergillosis (IA) is the most common life-threatening invasive mold infection worldwide. The principal therapy for IA is amphotericin B, despite its known toxicity and immunosuppressive side effects. Studies in animal models of IA suggest a role for T lymphocytes in the pathology of the disease, although the precise role for Aspergillus-specific T cells remains undefined. The isolation and characterization of T lymphocytes in animal models of IA are hampered by the rapid outgrowth of the fungus in cultures derived from infected organs. In the present study, we tested the abilities of the antifungal drugs caspofungin acetate and voriconazole to inhibit fungal growth in vitro as a means of maintaining cultures of T cells from Aspergillus-infected mice. We demonstrate that while both antifungal drugs are inhibitory, only voriconazole completely inhibited fungal growth, allowing long-term maintenance of T-cell cultures. In addition, voriconazole had no inhibitory effect on the activation and maturation of dendritic cells or the proliferation of T lymphocytes. Thus, voriconazole appears to be a promising agent for use in in vitro studies of Aspergillus-specific T lymphocytes in animal models of IA.

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CD28 engagement inhibits CD73-mediated regulatory activity of CD8+ T cells

Communications Biology ◽

10.1038/s42003-021-02119-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yo-Ping Lai ◽

Lu-Cheng Kuo ◽

Been-Ren Lin ◽

Hung-Ju Lin ◽

Chih-Yu Lin ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Human Tumor ◽

Cd28 Costimulation ◽

Tumor Mouse Model ◽

Cd73 Expression ◽

Costimulatory Pathway

AbstractCD28 is required for T cell activation as well as the generation of CD4+Foxp3+ Treg. It is unclear, however, how CD28 costimulation affects the development of CD8+ T cell suppressive function. Here, by use of Hepa1.6.gp33 in vitro killing assay and B16.gp33 tumor mouse model we demonstrate that CD28 engagement during TCR ligation prevents CD8+ T cells from becoming suppressive. Interestingly, our results showed that ectonucleotidase CD73 expression on CD8+ T cells is upregulated in the absence of CD28 costimulation. In both murine and human tumor-bearing hosts, CD73 is upregulated on CD28−CD8+ T cells that infiltrate the solid tumor. UPLC-MS/MS analysis revealed that CD8+ T cells activation without CD28 costimulation produces elevated levels of adenosine and that CD73 mediates its production. Adenosine receptor antagonists block CD73-mediated suppression. Our data support the notion that CD28 costimulation inhibits CD73 upregulation and thereby prevents CD8+ T cells from becoming suppressive. This study uncovers a previously unidentified role for CD28 costimulation in CD8+ T cell activation and suggests that the CD28 costimulatory pathway can be a potential target for cancer immunotherapy.

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CD4+ICOS+ T lymphocytes inhibit T cell activation ‘in vitro’ and attenuate autoimmune encephalitis ‘in vivo’

International Immunology ◽

10.1093/intimm/dxn016 ◽

2008 ◽

Vol 20 (4) ◽

pp. 577-589 ◽

Cited By ~ 18

Author(s):

Jose M. Rojo ◽

Eliana Pini ◽

Gloria Ojeda ◽

Raquel Bello ◽

Chen Dong ◽

...

Keyword(s):

T Cell ◽

T Lymphocytes ◽

T Cell Activation ◽

Cell Activation ◽

Autoimmune Encephalitis

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Platelet-Induced T Cell Activation in Patients with Myocardial Infarction; The Role of miR155

Blood ◽

10.1182/blood.v128.22.4913.4913 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4913-4913 ◽

Cited By ~ 1

Author(s):

Elena E. Solomou ◽

Elena Kalyvioti ◽

Evgenia Verigou ◽

Katerina Katsanaki ◽

Charalambos Gogos ◽

...

Keyword(s):

Myocardial Infarction ◽

T Cells ◽

T Cell ◽

Platelet Activation ◽

T Cell Activation ◽

Real Time Pcr ◽

Healthy Subjects ◽

Cell Activation ◽

Control Group

Abstract Specific aim: We have previously shown that platelets from patients with myocardial infarction (with ST elevation-STEMI) can activate T cells in vitro. In this study we wanted to expand our initial observation and explore the mechanism of this T cell activation. Methods: After written informed consent was obtained, peripheral blood mononuclear cells (PBMCs) were isolated from heparinized venous blood obtained from 30 patients with STEMI (28 men and 2 women) at the time of hospital admission at diagnosis, before receiving any treatment, as well as 5 days and 30 days later. We also analyzed 15 healthy subjects (12 men and 3 women), and 7 patients with unstable angina who served as the disease control group. PBMCs were analyzed by flow cytometry with the following markers and their isotypic controls: CD4, CD25, CD127, FOXP3, and CD69. We also isolated platelet rich plasma or plasma alone from the patients and the healthy subjects, and used in mixed cultures with PBMCs. miR 155 levels were examined with real-time PCR. Results: Initially, we incubated T cells with platelets from patients with STEMI and examined T cell activation by CD69 expression. These T cells showed increased expression of CD69 compared to T cells treated with platelets from healthy subjects (p<0.05). No T cell activation was observed following incubation with plasma alone from patients or healthy controls. Next, the percentages of CD4+CD25+hi CD127low FOXP3+ (regulatory T cells, Tregs) were examined in all study subjects. Patients at presentation showed comparable Treg levels with the controls (healthy subjects and disease control group). Five days later, patients with STEMI displayed increased levels of Tregs compared with the controls (p<0.05) (Fig.2). To explore the mechanism of Treg up-regulation the miR155 levels through real time PCR were evaluated. Patients with STEMI showed comparable levels of miR155 at presentation, but five days later showed decreased miR155 levels compared to controls (p<0.001) (Fig. 1); we observed an inverse correlation between miR155 levels and Treg numbers in patients with STEMI. At re-evaluation, one month later, patients with STEMI displayed Treg numbers comparable to the initial presentation levels Conclusion: Herein, we show that platelets from patients with STEMI can activate T cells in vitro. This platelet activation in patients with STEMI, results in an increase in Tregs through down-regulation of miR155, that return to normal levels a month later. This Treg increase reflects possibly an effort to suppress immune system activation secondary to platelet activation, shortly after the infarct. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures No relevant conflicts of interest to declare.

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Natural inhibitors of T-cell activation in Hodgkin's disease

Blood ◽

10.1182/blood.v78.9.2365.2365 ◽

1991 ◽

Vol 78 (9) ◽

pp. 2365-2371 ◽

Cited By ~ 8

Author(s):

M Roux ◽

B Schraven ◽

A Roux ◽

H Gamm ◽

R Mertelsmann ◽

...

Keyword(s):

T Cell ◽

T Lymphocytes ◽

T Cell Activation ◽

Hodgkin's Disease ◽

Cell Activation ◽

Cell Function ◽

Hodgkin’S Disease ◽

Alternative Pathway ◽

Cellular Level

Abstract Secondary immunodeficiency is frequently observed in Hodgkin's disease (HD) and is due in part to impaired T-cell function. Using monoclonal antibodies that bind to triggering molecules of human T lymphocytes (CD3/Ti antigen receptor; CD2 E-rosette receptor) and exert functional effects on T-cell activation, we have investigated in vitro immune responses of circulating lymphocytes from patients with HD in progression (n = 9) and in remission (n = 14). In patients with progressive HD, a severe dysfunction of the alternative CD2-mediated T- cell activation pathway was detected (49.3 +/- 14.2 v 9.4 +/- 5.1 cpm x 10(-3), in controls, P less than .01; n = 9) that parallels the reduced capacity of T lymphocytes to form rosettes with sheep red blood cells. Diminished alternative pathway activation in HD is not only due to a defect at the cellular level but also due to soluble mediators in the patients' plasma. Plasma from patients in progression markedly reduces CD2 mediated activation (P less than .01). These activities interfere, at least in part, with CD2/CD58 interactions and, therefore, reduce T- lymphocyte triggering through this amplifier mechanism.

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