scholarly journals Phenotype, Localization, and Mechanism of Suppression of CD4+CD25+ Human Thymocytes

2002 ◽  
Vol 196 (3) ◽  
pp. 379-387 ◽  
Author(s):  
Francesco Annunziato ◽  
Lorenzo Cosmi ◽  
Francesco Liotta ◽  
Elena Lazzeri ◽  
Roberto Manetti ◽  
...  
Keyword(s):  
T Cells ◽  
Transforming Growth Factor ◽  
Mixed Lymphocyte Culture ◽  
Interferon Γ ◽  
Lymphocyte Culture ◽  
Target Cells ◽  
Suppressive Activity ◽  
Α Chain ◽  
Tgf Β1

Phenotypic markers, localization, functional activities, and mechanisms of action in vitro of CD4+CD25+ T cells, purified from postnatal human thymuses, were investigated. These cells showed poor or no proliferation in mixed lymphocyte culture (MLC), and suppressed in a dose-dependent fashion the proliferative response to allogeneic stimulation of CD4+CD25− thymocytes. Virtually all CD4+CD25+ thymocytes constitutively expressed cytoplasmic T lymphocyte antigen (CTLA)-4, surface tumor necrosis factor type 2 receptor (TNFR2), and CCR8. They prevalently localized to perivascular areas of fibrous septa and responded to the chemoattractant activity of CCL1/I-309, which was found to be produced by either thymic medullary macrophages or fibrous septa epithelial cells. After polyclonal activation, CD4+CD25+ thymocytes did not produce the cytokines interleukin (IL)-2, IL-4, IL-5, IL-13, interferon γ, and only a very few produced IL-10, but all they expressed on their surface CTLA-4 and the majority of them also transforming growth factor (TGF)-β1. The suppressive activity of these cells was contact dependent and associated with the lack of IL-2 receptor (IL-2R) α-chain (CD25) expression in target cells. Such a suppressive activity was partially inhibited by either anti–CTLA-4 or anti–TGF-β1, and was completely blocked by a mixture of these monoclonal antibodies, which were also able to restore in target T cells the expression of IL-2R α-chain and, therefore, their responsiveness to IL-2. These data demonstrate that CD4+CD25+ human thymocytes represent a population of regulatory cells that migrate in response to the chemokine CCL1/I-309 and exert their suppressive function via the inhibition of IL-2R α-chain in target T cells, induced by the combined activity of CTLA-4 and membrane TGF-β1.

scholarly journals Sequential responses of mouse spleen T cells in mixed lymphocyte culture-induced cytolysis.

1975 ◽  
Vol 141 (2) ◽  
pp. 508-512 ◽  
Author(s):  
P Häyry ◽  
L C Andersson
Keyword(s):  
T Cells ◽  
Mixed Lymphocyte Culture ◽  
Lymphocyte Culture ◽  
Mouse Spleen ◽  
Blast Transformation

T cells triggered to blast transformation and proliferation by histoincompatible cells have the capacity of reverting "back" to lymphocytes. These "secondary" lymphocytes and their progeny cells are able to respond repeatedly to the same allogeneic stimulus in vitro.

scholarly journals Haplotype-specific suppression of cytotoxic T cell induction by antigen inappropriately presented on T cells.

1983 ◽  
Vol 157 (1) ◽  
pp. 141-154 ◽  
Author(s):  
P J Fink ◽  
I L Weissman ◽  
M J Bevan
Keyword(s):  
T Cells ◽  
Cytotoxic T Lymphocyte ◽  
Mixed Lymphocyte Culture ◽  
Lymphocyte Culture ◽  
Cytotoxic T Cell ◽  
Spleen Cells ◽  
Specific Suppression ◽  
Veto Cells

To detect a strong cytotoxic T lymphocyte (CTL) response to minor histocompatibility (H) antigens in a 5-d mixed lymphocyte culture, it is necessary to use a responder that has been primed in vivo with antigen-bearing cells. It has previously been shown that minor-H-specific CTL can be primed in vivo both directly by foreign spleen cells and by presentation of foreign minor H antigens on host antigen-presenting cells. This latter route is evident in the phenomenon of cross-priming, in which H-2 heterozygous (A x B)F1 mice injected 2 wk previously with minor H-different H-2A (A') spleen cells generate both H-2A- and H-2B-restricted minor-H-specific CTL. In a study of the kinetics of direct- vs. cross-priming to minors in F1 mice, we have found that minor H-different T cells actually suppress the induction of virgin CTL capable of recognizing them. CTL activity measured from F1 mice 3-6 d after injection with viable A' spleen cells is largely H-2B restricted. The H-2A-restricted response recovers such that roughly equal A- and B-restricted activity is detected in mice as early as 8-10 d postinjection. This temporary hyporeactivity does not result from generalized immunosuppression--it is specific for those CTL that recognize the foreign minor H antigen in the context of the H-2 antigens on the injected spleen cells. The injected spleen cells that mediate this suppression are radiosensitive T cells; Lyt-2+ T cells are highly efficient at suppressing the induction of CTL in vivo. No graft vs. host reaction by the injected T cells appears to be required, as suppression of direct primed CTL can be mediated by spleen cells that are wholly tolerant of both host H-2 and minor H antigens. Suppression cannot be demonstrated by in vitro mixing experiments. Several possible mechanisms for haplotype-specific suppression are discussed, including inactivation of responding CTL by veto cells and in vivo sequestration of responding CTL by the injected spleen cells.

scholarly journals Transforming Growth Factor β1 Production by CD4+ CD25+ Regulatory T Cells in Peripheral Blood Mononuclear Cells from Healthy Subjects Stimulated with Leishmania guyanensis

2005 ◽  
Vol 73 (9) ◽  
pp. 5908-5914 ◽  
Author(s):  
A. Kariminia ◽  
E. Bourreau ◽  
H. Pascalis ◽  
P. Couppié ◽  
D. Sainte-Marie ◽  
...  
Keyword(s):  
T Cells ◽  
Growth Factor ◽  
Healthy Subjects ◽  
Mononuclear Cells ◽  
Transforming Growth Factor ◽  
Suppressive Activity ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
Leishmania Guyanensis ◽  
Tgf Β1

ABSTRACT Transforming growth factor β (TGF-β) has been shown to be a central immunomodulator used by leishmaniae to escape effective mechanisms of protection in human and murine infections with these parasites. However, all the information is derived from studies of established infection, while little is known about TGF-β production in response to Leishmania stimulation in healthy subjects. In this study, TGF-β1 production was demonstrated in peripheral blood mononuclear cells from healthy subjects never exposed to leishmaniae in response to live Leishmania guyanensis, and the TGF-β1-producing cells were described as a distinct subpopulation of CD4+ CD25+ regulatory T cells. The suppressive properties of CD4+ CD25+ T cells were demonstrated in vitro by their inhibition of production of interleukin 2 (IL-2) and IL-10 by CD4+ CD25− T cells in the presence of either anti-CD3 or L. guyanensis. Although neutralization of TGF-β1 did not reverse the suppressive activity of CD4+ CD25+ T cells activated by anti-CD3, it reversed the suppressive activity of CD4+ CD25+ T cells activated by L. guyanensis. Altogether our data demonstrated that TGF-β1 is involved in the suppressive activity of L. guyanensis-stimulated CD4+ CD25+ T cells from healthy controls.

Leflunomide induces immunosuppression in collagen-induced arthritis rats by upregulating CD4+CD25+ regulatory T cells

2010 ◽  
Vol 88 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Ting-Yu Wang ◽  
Jun Li ◽  
Chang-Yu Li ◽  
Yong Jin ◽  
Xiong-Wen Lü ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Regulatory T Cells ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Con A ◽  
Collagen Induced Arthritis ◽  
Foxp3 Mrna ◽  
Tgf Β1

This study was to investigate the effect of leflunomide on the immunosuppressive CD4+CD25+ regulatory T cells (CD4+CD25+ Tregs) in collagen-induced arthritis (CIA) rats. CIA was induced by collagen type II in Wistar rats. Immunofluorescence flow cytometry and RT-PCR were used to determine the proportion of CD4+CD25+ Tregs and the expression of Foxp3 mRNA, respectively. Proliferation of T lymphocytes was assayed with MTT reagent, and the level of transforming growth factor β1 (TGF-β1) in the supernatant of concanavalin A (Con A)-induced T lymphocytes was determined by ELISA kit. Our investigations demonstrated that inhibition of arthritis by leflunomide was related to changes in CD4+CD25+ Tregs. In addition, A771726, which is the active metabolite of leflunomide, promoted the differentiation of spleen lymphocytes into CD4+CD25+ Tregs, increased antiinflammatory cytokine TGF-β1 secretion, and adjusted the activity of Con A-induced lymphocytes in vitro.

scholarly journals Effect of activated lymphocytes on the regulation of hematopoiesis: enhancement and suppression of in vitro BFU-E growth by T cells stimulated by autologous non-T cells

Blood ◽  
1986 ◽  
Vol 67 (4) ◽  
pp. 1143-1147 ◽  
Author(s):  
M Harada ◽  
S Nakao ◽  
K Kondo ◽  
K Odaka ◽  
M Ueda ◽  
...  
Keyword(s):  
T Cells ◽  
Mononuclear Cells ◽  
Colony Growth ◽  
Mixed Lymphocyte Culture ◽  
Lymphocyte Culture ◽  
T Cell Subsets ◽  
Activated T Cells ◽  
Peripheral Blood Mononuclear ◽  
Erythroid Progenitor

Abstract Autologous mixed lymphocyte culture (AMLR) is an immunologic response with memory and specificity and plays a role in immune regulation. Effects of T cells activated by AMLR were studied in the regulation of in vitro erythropoiesis. AMLR-activated T cells were cocultured with autologous non-T, nonphagocytic peripheral blood mononuclear cells for assaying erythroid progenitor cells (BFU-E). T cells activated for 3 days in AMLR showed significant enhancement of in vitro colony growth by BFU-E. In contrast, activated T cells from day 7 AMLR caused significant suppression of BFU-E growth. Both enhancing and suppressing activities of AMLR-activated T cells were mediated by an la-positive and radiosensitive population within the OKT4+ subset. These observations suggest that AMLR-activated T cells may play a role in the immune-mediated regulation of in vitro erythropoiesis. It is also suggested that heterogeneous T-cell subsets may exert regulatory functions in the regulation of in vitro hematopoiesis.

scholarly journals Characterization of Mice with a Platelet-Specific Deletion of the Adapter Molecule ADAP

2019 ◽  
Vol 39 (9) ◽  
Author(s):  
Jochen Michael Rudolph ◽  
Karina Guttek ◽  
Gabriele Weitz ◽  
Clara Antonia Meinke ◽  
Stefanie Kliche ◽  
...  
Keyword(s):  
T Cells ◽  
Knockout Mice ◽  
Transforming Growth Factor ◽  
Severe Disease ◽  
Transforming Growth Factor Β1 ◽  
Regulatory Function ◽  
Platelet Factor ◽  
Tgf Β1

ABSTRACT The adhesion and degranulation-promoting adapter protein (ADAP) is expressed in T cells, NK cells, myeloid cells, and platelets. The involvement of ADAP in the regulation of receptor-mediated inside-out signaling leading to integrin activation is well characterized, especially in T cells and in platelets. Due to the fact that animal studies using conventional knockout mice are limited by the overlapping effects of the different ADAP-expressing cells, we generated conditional ADAP knockout mice (ADAPfl/fl PF4-Cretg) (PF4, platelet factor 4). We observed that loss of ADAP restricted to the megakaryocytic lineage has no impact on other hematopoietic cells even under stimulation conditions. ADAPfl/fl PF4-Cretg mice showed thrombocytopenia in combination with reduced plasma levels of PF4 and transforming growth factor β1 (TGF-β1). In vitro, platelets from these mice revealed reduced P-selectin expression, lower levels of TGF-β1 release, diminished integrin αIIbβ3 activation, and decreased fibrinogen binding after stimulation with podoplanin, the ligand of C-type lectin-like receptor 2 (CLEC-2). Furthermore, loss of ADAP was associated with impaired CLEC-2-mediated activation of phospholipase Cγ2 (PLCγ2) and extracellular signal-regulated kinase 1/2 (ERK1/2). Induction of experimental autoimmune encephalomyelitis (EAE) in mice lacking ADAP expression in platelets caused a more severe disease. In vivo administration of TGF-β1 early after T cell transfer reduced EAE severity in mice with loss of ADAP restricted to platelets. Our results reveal a regulatory function of ADAP in platelets in vitro and during autoimmune disease EAE in vivo.

scholarly journals Surface markers of cloned human T cells with various cytolytic activities.

1981 ◽  
Vol 154 (2) ◽  
pp. 569-574 ◽  
Author(s):  
L Moretta ◽  
M C Mingari ◽  
P R Sekaly ◽  
A Moretta ◽  
B Chapuis ◽  
...  
Keyword(s):  
T Cells ◽  
Cytotoxic T Lymphocyte ◽  
Mixed Lymphocyte Culture ◽  
Lymphocyte Culture ◽  
Target Cells ◽  
Surface Markers ◽  
Human T Cells ◽  
Dependent Cell ◽  
Blast Cells ◽  
Ctl Activity

Human T cells stimulated in secondary allogeneic mixed lymphocyte culture (MLC) were cloned under limiting conditions in microculture systems using T cell growth factor and irradiated allogeneic cells. Clones with lytic activity against either phytohemagglutinin-induced blast cells bearing the stimulating alloantigen(s) (cytotoxic T lymphocyte [CTL] activity), L1210 mouse lymphoma cells coated with rabbit antibody (antibody-dependent cell-mediated cytotoxicity [ADCC]), or K562 human target cells were selected, expanded, and then analyzed for different surface markers, including rosette formation with sheep erythrocytes (E rosettes), receptors for the fc portion of IgG or IgM (Fc gamma R and Fc mu R), and a group of antigens recognized by monoclonal antibodies including Ia, 4F2, OKT8,a nd OKT4. All the cytotoxic cells were E rosette+, Ia+ and 4f2+. Expression of Fc gamma R was restricted to the clones active in ADCC. CTL clones were either OKT8+ or OKT8-. Furthermore, three of the OKT8- CTL clones were OKT4+. In addition, some cytolytic clones devoid of specific CTL activity were OKT8+. It thus appears that the claim that human CTL are OKT8+, OKT4-, and Ia- is not supported by the analysis of their phenotype at the clonal level.

scholarly journals CD4+CD25+ Regulatory T Cells Can Mediate Suppressor Function in the Absence of Transforming Growth Factor β1 Production and Responsiveness

2002 ◽  
Vol 196 (2) ◽  
pp. 237-246 ◽  
Author(s):  
Ciriaco A. Piccirillo ◽  
John J. Letterio ◽  
Angela M. Thornton ◽  
Rebecca S. McHugh ◽  
Mizuko Mamura ◽  
...  
Keyword(s):  
T Cells ◽  
Growth Factor ◽  
Regulatory T Cells ◽  
T Cell Activation ◽  
Transforming Growth Factor ◽  
Cell Contact ◽  
Suppressor Function ◽  
Tgf Β1

CD4+CD25+ regulatory T cells inhibit organ-specific autoimmune diseases induced by CD4+CD25−T cells and are potent suppressors of T cell activation in vitro. Their mechanism of suppression remains unknown, but most in vitro studies suggest that it is cell contact–dependent and cytokine independent. The role of TGF-β1 in CD4+CD25+ suppressor function remains unclear. While most studies have failed to reverse suppression with anti–transforming growth factor (TGF)-β1 in vitro, one recent study has reported that CD4+CD25+ T cells express cell surface TGF-β1 and that suppression can be completely abrogated by high concentrations of anti–TGF-β suggesting that cell-associated TGF-β1 was the primary effector of CD4+CD25+-mediated suppression. Here, we have reevaluated the role of TGF-β1 in CD4+CD25+-mediated suppression. Neutralization of TGF-β1 with either monoclonal antibody (mAb) or soluble TGF-βRII-Fc did not reverse in vitro suppression mediated by resting or activated CD4+CD25+ T cells. Responder T cells from Smad3−/− or dominant-negative TGF-β type RII transgenic (DNRIITg) mice, that are both unresponsive to TGF-β1–induced growth arrest, were as susceptible to CD4+CD25+-mediated suppression as T cells from wild-type mice. Furthermore, CD4+CD25+ T cells from neonatal TGF-β1−/− mice were as suppressive as CD4+CD25+ from TGF-β1+/+ mice. Collectively, these results demonstrate that CD4+CD25+ suppressor function can occur independently of TGF-β1.

The Link Between Seminal Cytokine Interleukin 18, Female Circulating Regulatory T Cells, and IVF/ICSI Success

2018 ◽  
Vol 26 (8) ◽  
pp. 1034-1044 ◽  
Author(s):  
Marina Nikolaeva ◽  
Alina Babayan ◽  
Elena Stepanova ◽  
Alla Arefieva ◽  
Tatiana Dontsova ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Peripheral Blood ◽  
Transforming Growth Factor ◽  
Embryo Implantation ◽  
Female Reproductive Tract ◽  
Vitro Fertilization ◽  
Treg Frequency ◽  
Tgf Β1

Seminal plasma (SP) is thought to be a crucial factor which affects the expansion of regulatory T cells (Tregs) in female reproductive tract during embryo implantation. We propose that seminal transforming growth factor (TGF) β1 is responsible for local accumulation of circulating Tregs, which manifests as changes in Treg frequency in peripheral blood, whereas seminal interleukin (IL) 18 interferes with TGF-β1-dependent cellular reactions. The purpose of the present study is to determine whether the frequency of circulating Tregs is associated with the levels of seminal cytokines and pregnancy establishment in women exposed to partner’s SP during in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycle. Twenty-nine women were exposed to SP via timed intercourse before the day of ovum pickup (day-OPU) and also subjected to intravaginal SP application just after OPU. Measurements of seminal TGF-β1 and IL-18 were made by FlowCytomix technology. The percentage of CD4+CD25+CD127low+/ – Tregs among total circulating CD4+ T cells was determined by flow cytometry and the difference between Treg values on the day of embryo transfer and day-OPU was calculated. The percentage of Tregs on the day-OPU, identified as a predictive factor of clinical pregnancy after IVF/ICSI, showed a positive correlation with IL-18 concentration and content of this cytokine per ejaculate ( P < .001 and P < .004, respectively) and negative correlation with the TGF-β1/IL-18 ratio ( P < .014).These findings indicate that the adverse effect of seminal IL-18 excess on implantation may be realized by the prevention of postcoital TGF-β1-related migration of circulating Tregs, which clearly manifests as elevated level of Treg frequency in peripheral blood.

scholarly journals The Suppression of Th1 Response by Inducing TGF-β1 From Regulatory T Cells in Bovine Mycoplasmosis

2020 ◽  
Vol 7 ◽  
Author(s):  
Yamato Sajiki ◽  
Satoru Konnai ◽  
Shinya Goto ◽  
Tomohiro Okagawa ◽  
Kosuke Ohira ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Immune Responses ◽  
Immune Cells ◽  
Transforming Growth Factor ◽  
Interleukin 10 ◽  
Infected Cattle ◽  
Chronic Infections ◽  
Tgf Β1

Regulatory T cells (Tregs) regulate immune responses and maintain host immune homeostasis. Tregs contribute to the disease progression of several chronic infections by oversuppressing immune responses via the secretion of immunosuppressive cytokines, such as transforming growth factor (TGF)-β and interleukin-10. In the present study, we examined the association of Tregs with Mycoplasma bovis infection, in which immunosuppression is frequently observed. Compared with uninfected cattle, the percentage of Tregs, CD4+CD25highFoxp3+ T cells, was increased in M. bovis-infected cattle. Additionally, the plasma of M. bovis-infected cattle contained the high concentrations of TGF-β1, and M. bovis infection induced TGF-β1 production from bovine immune cells in in vitro cultures. Finally, we analyzed the immunosuppressive effects of TGF-β1 on bovine immune cells. Treatment with TGF-β1 significantly decreased the expression of CD69, an activation marker, in T cells, and Th1 cytokine production in vitro. These results suggest that the increase in Tregs and TGF-β1 secretion could be one of the immunosuppressive mechanisms and that lead to increased susceptibility to other infections in terms of exacerbation of disease during M. bovis infection.

Sign in / Sign up

Export Citation Format

Share Document