scholarly journals Differential transcription directed by discrete gamma interferon promoter elements in naive and memory (effector) CD4 T cells and CD8 T cells.

1997 ◽  
Vol 17 (1) ◽  
pp. 199-208 ◽  
Author(s):  
T M Aune ◽  
L A Penix ◽  
M R Rincón ◽  
R A Flavell
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Transcriptional Activity ◽  
Memory T Cells ◽  
Gamma Interferon ◽  
Ifn Gamma ◽  
Naïve T Cells

Acquisition of the ability to produce gamma interferon (IFN-gamma) is a fundamental property of memory T cells and enables one subset (T helper 1 [TH1]) to deliver its effector functions. To examine regulation of IFN-gamma gene expression in a model system which recapitulates TH1 differentiation, we prepared reporter transgenic mice which express the luciferase gene under the control of proximal and distal regulatory elements (prox.IFN gamma and dist.IFN gamma) from the IFN-gamma promoter. Memory T cells, but not naive T cells, secreted IFN-gamma and expressed both prox.IFN gamma and dist.IFN gamma transcriptional activities. Naive T cells required priming to become producers of IFN-gamma and to direct transcription by these elements. While both CD4+ and CD8+ T cells produced IFN-gamma, only CD4+ T cells expressed prox.IFN gamma transcriptional activity. Induction of transcriptional activity was inhibited by known antagonists of effector T-cell populations. Cyclosporin A inhibited transcriptional activity directed by both elements in effector T cells. Elevated cyclic AMP inhibited transcriptional activity directed by prox.IFN gamma in primed CD4+ T cells but enhanced transcriptional activity directed by dist.IFN gamma in primed CD8+ T cells. Taken together, these data show that prox.IFN gamma and dist.IFN gamma transcriptional activities mirror IFN-gamma gene expression in naive and memory CD4+ T cells but suggest that differences exist in regulation of IFN-gamma gene expression in CD4+ and CD8+ T-cell subsets.

scholarly journals Induction of memory-like CD8 + T cells and CD4 + T cells from human naïve T cells in culture

2021 ◽  
Author(s):  
Yasuhito Tokumoto ◽  
Yasuto Araki ◽  
Yusuke Narizuka ◽  
Yosuke Mizuno ◽  
Susumu Ohshima ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Memory T Cells ◽  
Quiescent State ◽  
Naive T Cells ◽  
Naïve T Cells ◽  
Cells In Culture ◽  
Human T Cells

Abstract Memory T cells are crucial players in vertebrate adaptive immunity but their development is incompletely understood. Here we describe a method to produce human memory-like T cells from naïve human T cells in culture. Using commercially available human T cell differentiation kits, both purified naïve CD8 + T cells and purified naïve CD4 + T cells were activated via T cell receptor signaling and appropriate cytokines for several days in culture. All the T cell activators were then removed from the medium and the cultures were continued in hypoxic condition (1% O2 atmosphere) for several more days; during this period, most of the cells died, but some survived in a quiescent state for a month. The survivors had small round cell bodies, expressed differentiation markers characteristic of memory T cells and restarted proliferation when the T cell activators were added back. We could also induce memory-like T cells from naïve human T cells without hypoxia, if we froze the activated T cells or prepared the naïve T cells from chilled filter buffy coats.

scholarly journals Donor Lymphocyte Infusions Correct Deficiency of Naive T Cells and Improve T-Cell Competence after Allogeneic Haematopoietic Stem Cell Transplantation with Lymphocyte Depletion

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2233-2233
Author(s):  
Monera Al Rukhayes ◽  
Victoria T Potter ◽  
Pilar Perez-Abellan ◽  
Jesus Feliu ◽  
Lajos Floro ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Healthy Volunteers ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Haematopoietic Stem Cell ◽  
Naive T Cells ◽  
Lymphocyte Depletion ◽  
Naïve T Cells ◽  
Repertoire Diversity

Abstract Lymphocyte-depletion effectively reduces risk of graft versus host disease (GvHD) after allogeneic haematopoietic stem cell transplantation (allo-HSCT), but risk of infections and malignant disease relapse remains high. We have previously reported that pre-emptive donor lymphocyte infusions (pDLI) given to patients after allo-HSCT for myeloid malignancies to reverse falling donor T-cell chimerism improve overall and relapse-free survival. GvHD rates after pDLI were not high and grade rarely severe. To investigate the basis for better outcome after pDLI, we have assessed recovery of lymphocyte subsets, T-cell receptor (TCR) diversity and T-cell functional competence after allo-HSCT with fludarabine and busulphan in cohorts of 59 patients (median age 59) given alemtuzumab for lymphocyte-depletion and 34 patients (median age 58) given anti-thymocyte globulin (ATG). Lymphocytes were significantly less depleted with ATG compared to alemtuzumab (Day 30: Median 3.9 x 108/liter versus 2.3x108/liter, P=0.03) but numbers for both ATG and alemtuzumab remained significantly below the normal range (median 2.34x109/liter for 11 aged-matched healthy volunteers) for at least one year (Day 360 P<0.005: Median 8.35 x 108/liter after ATG; median 1.04 x 109/liter after alemtuzumab). Lymphocyte subset composition was similar after ATG or alemtuzumab, and abnormal. Notable, the T-cell population comprised only memory and effector T cells early after HSCT. These cells expressed significantly higher levels of Ki67 than T cells from healthy volunteers (Day 30 P<0.005: Median CD4 T cells 41.3% Ki67+ after ATG, 66% after alemtuzumab compared to 2.51% for healthy volunteers; median CD8 T cells 18.5% Ki67+ after ATG, 50.8% after alemtuzumab compared to 2.58% for healthy volunteers). This marker is indicative of homeostatic proliferation likely driven by increased levels of IL7 and IL15 detected in the serum of patients early after HSCT compared to healthy volunteers (Day 30 P=0.066 and P<0.005 respectively). Higher frequency of T cells expressing the proliferation marker in patients treated with alemtuzumab was associated with high frequencies of T cells expressing the PD1 marker, indicative of exhaustion (Day 30 P<0.005: Median CD4 T cells 84.0% PD1+ after alemtuzumab compared to 6.35% for healthy volunteers; median CD8 T cells 49.1% PD1+ after alemtuzumab compared to 12.3% for healthy volunteers). Expression of PD1 by T cells was near normal in patients treated with ATG. Naïve T cells were typically absent for at least six months after HSCT following lymphocyte depletion with ATG or alemtuzumab, and any subsequent recovery was poor. In contrast, the naïve T-cell population increased rapidly in patients after pDLI (n=18). Six of these patients received pDLI early after HSCT (at 3-5 months) and naïve T-cell recovery was significantly enhanced at six months compared to patients that did not receive pDLI (Day 180 P<0.005: Median 19.25% naïve CD4 T cells compared to 1.36%; median 23.5% naïve CD8 T cells compared to 3.48%). Naïve T cells are the main source of repertoire diversity and responsible for responses to antigens not previously encountered. Analysis of the TCR β chain repertoire of five patients by deep sequencing revealed that pDLI boosts repertoire diversity. For example, unique TCR β chain sequences increased 31-fold in 150 days after pDLI compared to a 2-fold increase during a similar period for another patient that did not receive DLI. Furthermore, instances of emergence of public clonotypes specific for CMV or EBV that were not detected before DLI were seen in virus-positive patients whose donors were virus-negative. Emergence and rapid expansion of donor-derived clonotypes to frequencies up to 6.75% suggests that naïve T cells present in the DLI had been primed upon encounter with virus in the patient. In vitro stimulation with overlapping 15-mer peptide libraries for CMV antigens and EBV antigens followed by assessment of activation marker expression and interferon-γ, MIP-1β, and TNF-α production showed that virus-specific T-cell responses increased in magnitude and poly-functionality after DLI. These findings show that DLI replenishes naïve T cells and restores ability to respond to viral antigens previously unseen. By inference, this may extend to leukaemia antigens and underlie the reduced rate of malignant disease relapse seen in patients given pDLI. Disclosures No relevant conflicts of interest to declare.

Ex Vivo Fludarabine Selectively Depletes Human Naive T-Cell Subsets: A Step Toward Modifying Donor Lymphocyte Infusion.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1071-1071
Author(s):  
Melody M. Smith ◽  
Cynthia R. Giver ◽  
Edmund K. Waller ◽  
Christopher R. Flowers
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Memory T Cells ◽  
Ex Vivo ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Naïve T Cell ◽  
Naive T Cell

Abstract Ex vivo modification of donor lymphocytes with purine analogs (mDL) may help to minimize graft versus host disease (GvHD) while providing beneficial graft versus leukemia (GvL) effects. In a murine model system, we have shown that allogeneic donor splenocytes, treated with fludarabine ex vivo have significantly reduced GvHD activity when transferred to irradiated recipient mice, and retain anti-viral and GvL activities (Giver, 2003). This effect appears to be mediated by relative depletion of donor CD4 CD44low, “naive” T-cells. As a first step toward developing mDL for use in patients, we sought to evaluate the effects of ex vivo fludarabine exposure on human T-cell subsets, and to determine the minimum dose of fludarabine required to achieve this effect. Methods: Peripheral blood mononuclear cell samples from 6 healthy volunteers were evaluated at 0, 24, 48, and 72 hour time points after ex vivo incubation in varying dosages of fludarabine: 2, 5, and 10(n=3) mcg/ml. Fludarabine incubated samples were compared to samples that received no fludarabine (untreated). The total viable cell number was determined and the fractions and absolute numbers of viable CD4 and CD8 naïve and memory T-cells were determined using flow cytometry after incubation with 7-AAD (dead cell stain), CD4, CD8, CD45RA, CD62L, and CCR7 antibodies, and measuring the total viable cells/ml. Results: The numbers of viable CD4 and CD8 T-cells remained relatively stable in control cultures. Without fludarabine, the average viability at 72 hr of naive and memory T-cells were 92% and 77% for CD4 and 86% and 63% for CD 8 (Fig. 1A). Naive CD4 T-cells were more sensitive to fludarabine-induced death than memory CD4 cells. At 72 hr, the average viability of fludarabine-treated naive CD4 T-cells was 33% at 2 mcg/ml (8.2X the reduction observed in untreated cells) and 30% at 5 mcg/ml, while memory CD4 T-cells averaged 47% viability at 2 mcg/ml (2.3X the reduction observed in untreated cells) (Fig. 1B) and 38% at 5 mcg/ml. The average viability of naive CD8 T-cells at 72 hr was 27% at 2 mcg/ml and 20% at 5 mcg/ml, while memory CD8 T-cell viability was 22% at 2 mcg/ml and 17% at 5 mcg/ml. Analyses on central memory, effector memory, and Temra T-cells, and B-cell and dendritic cell subsets are ongoing. The 5 and 10 mcg/ml doses also yielded similar results in 3 initial subjects, suggesting that 2 mcg/ml or a lower dose of fludarabine is sufficient to achieve relative depletion of the naive T-cell subset. Conclusions: Future work will determine the minimal dose of fludarabine to achieve this effect, test the feasibility of using ex vivo nucleoside analog incubation to reduce alloreactivity in samples from patient/donor pairs, and determine the maximum tolerated dose of mDL in a phase 1 clinical trial with patients at high risk for relapse and infectious complications following allogeneic transplantation. Figure Figure

scholarly journals CD8+CD44hi but not CD4+CD44hi memory T cells mediate potent graft antilymphoma activity without GVHD

Blood ◽  
2011 ◽  
Vol 117 (11) ◽  
pp. 3230-3239 ◽  
Author(s):  
Suparna Dutt ◽  
Jeanette Baker ◽  
Holbrook E. Kohrt ◽  
Neeraja Kambham ◽  
Mrinmoy Sanyal ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Memory T Cells ◽  
Cell Subset ◽  
B Cell Lymphoma ◽  
Effector Memory ◽  
T Cell Subset ◽  
Progressive Growth

Abstract Allogeneic hematopoietic cell transplantation can be curative in patients with leukemia and lymphoma. However, progressive growth of malignant cells, relapse after transplantation, and graft-versus-host disease (GVHD) remain important problems. The goal of the current murine study was to select a freshly isolated donor T-cell subset for infusion that separates antilymphoma activity from GVHD, and to determine whether the selected subset could effectively prevent or treat progressive growth of a naturally occurring B-cell lymphoma (BCL1) without GVHD after recipients were given T cell–depleted bone marrow transplantations from major histocompatibility complex–mismatched donors. Lethal GVHD was observed when total T cells, naive CD4+ T cells, or naive CD8+ T cells were used. Memory CD4+CD44hi and CD8+CD44hi T cells containing both central and effector memory cells did not induce lethal GVHD, but only memory CD8+ T cells had potent antilymphoma activity and promoted complete chimerism. Infusion of CD8+ memory T cells after transplantation was able to eradicate the BCL1 lymphoma even after progressive growth without inducing severe GVHD. In conclusion, the memory CD8+ T-cell subset separated graft antilymphoma activity from GVHD more effectively than naive T cells, memory CD4+ T cells, or memory total T cells.

Notch Inhibition in Alloreactive CD4+ and CD8+ T Cells Blocks Graft-Versus-Host Disease by Inducing a Hyporesponsive Program with Features of T Cell Anergy

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 340-340
Author(s):  
Ashley R Sandy ◽  
Jooho Chung ◽  
Ivy T Tran ◽  
Gloria T Shan ◽  
Ann Friedman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Notch Signaling ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Ifn Gamma ◽  
Cell Compartments ◽  
Alloreactive T Cells ◽  
Notch Inhibition

Abstract Abstract 340 Graft-versus-host disease (GVHD) is a significant cause of morbidity and mortality following allogeneic bone marrow transplantation (allo-BMT). We previously identified Notch signaling as an essential regulator of allogeneic CD4+ T cell responses mediating GVHD after allo-BMT. Alloreactive CD4+ T cells expressing the pan-Notch inhibitor DNMAML induced markedly less severe GVHD as compared to wild-type T cells, leading to improved survival of the recipients. Notch-deprived T cells had preserved in vivo expansion and cytotoxicity. However, alloreactive DNMAML CD4+ T cells produced markedly decreased amounts of multiple proinflammatory cytokines, including TNF-alpha, IFN-gamma, and IL-2. This was associated with increased expansion of Foxp3+ CD4+ T regulatory cells. Thus, Notch signaling is an attractive new therapeutic target to control GVHD without eliminating the anti-cancer activity of allo-BMT. To elucidate the mechanisms of Notch action in GVHD, we studied the effects of Notch inhibition in alloreactive CD4+ and CD8+ T cells using minor and major histocompatibility antigen-mismatched models of allo-BMT. In the B6 anti-BALB/b minor antigen-mismatched model, recipients of B6 T cells were protected from lethal acute GVHD upon DNMAML expression in the CD4+, CD8+ or both T cell compartments. In the B6 anti-BALB/c MHC-mismatched model, DNMAML CD4+ or CD8+ T cells transplanted alone or in combination induced significantly less GVHD and resulted in improved survival compared to wild-type T cells. Upon ex vivo restimulation with anti-CD3/CD28 antibodies, both CD4+ and CD8+ DNMAML alloreactive T cells had markedly decreased production of IFN-gamma. These findings suggest that Notch signaling has parallel functions in CD4+ and CD8+ T cells. We then studied expression of Tbx21 (encoding T-bet) and Eomes, the key transcription factors regulating Ifng transcription in CD4+ Th1 and CD8+ T cells, respectively. DNMAML alloreactive T cells had preserved amounts of Tbx21 mRNA and T-bet protein, and increased levels of Eomes transcripts and protein. These data differ from past reports indicating that Notch signaling controls T cell differentiation through direct regulation of Tbx21 and Eomes expression. Ex vivo restimulation of DNMAML CD4+ and CD8+ T cells with PMA (diacylglycerol analog) and ionomycin (calcium ionophore) rescued IFN-gamma production by both T cell compartments and partially restored IL-2 production by CD4+ T cells, suggesting abnormal signaling downstream of the T cell receptor. After anti-CD3/CD28 restimulation, DNMAML alloreactive T cells showed markedly decreased phosphorylation of Mek1 and Erk1/2, indicating defective Ras/MAPK activation. PMA was sufficient to rescue Erk1/2 activation. NFkB activity was also significantly impaired in alloreactive DNMAML T cells as assessed with a NFkB-luciferase reporter transgene. Abnormal responsiveness was acquired in vivo during alloreactive T cell priming, since naïve DNMAML T cells had preserved Ras/MAPK activation. Moreover, alloreactive Notch-deprived T cells had elevated levels of intracellular cAMP and increased expression of the anergy-associated genes, Dgka and Egr3. Thus, alloreactive DNMAML T cells had features reminiscent of T cell anergy. Given that in vivo proliferation in irradiated recipients and cytotoxicity of DNMAML alloreactive T cells were largely preserved, our data suggest a “split anergy” phenotype with differential effects on distinct T cell effector functions. Altogether, our results reveal a parallel role for Notch signaling in both the CD4+ and CD8+ T cell compartments that differ from all previous reports of Notch action in mature T cells. Understanding the role of Notch signaling in alloreactive T cells is essential for harnessing the therapeutic potential of Notch inhibition in GVHD. Disclosures: No relevant conflicts of interest to declare.

Bone Marrow Derived, De Novo Generated CD4+ T Cells Are Previously Unsuspected Participants in CD8+ T Cell-Mediated Graft-Versus-Host Disease.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 581-581
Author(s):  
Yi Zhang ◽  
Elizabeth Hexner ◽  
Dale Frank ◽  
Joe Gerard ◽  
Frank Kung ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Acute Gvhd ◽  
De Novo ◽  
Memory T Cells ◽  
Tissue Injury ◽  
Chronic Gvhd ◽  
Host Tissue

Abstract Although mature CD8+ T cells are known to be major effectors of acute GVHD, patients receiving T cell-depleted allografts remain at high risk for chronic GVHD. To what extent CD8+, CD4+ or both T cell subsets contribute to this chronic immunopathology is not known. We have recently demonstrated that alloreactive memory T cells develop in mice with acute GVHD and account for the persistence of host tissue injury (Journal of Immunology, 2005;174:3051). Based on these findings, we now ask whether de novo generated donor T cells from engrafted T-BM themselves contribute to persistent host tissue injury in GVHD. Confirming previous observations, we found that transplantation of lethally irradiated C57BL/6SJL (B6, CD45.1) mice with highly purified C3H.SW (CD45.2) CD4+ naïve T cells did not cause GVHD, but mice receiving highly purified CD8+ naïve T cells together with C3H.SW T-BM, suffered severe acute GVHD. Surprisingly, in these mice receiving only CD8+ T cells, a substantial number of donor CD4+ T cells as well as CD8+ T cells were detected in GVHD target tissues, indicating that these infiltrating CD4+ T cells had arisen de novo from the transplanted T-BM. Donor CD4+ T cells recovered from GVHD mice expressed surface markers of activated effector/effector memory T cells, including CD25, CD69, CXCR3, and CD44hiCD62Llo. In response to host DCs, purified GVHD CD4+ T cells proliferated and expanded 4-5X more, and produced 10X higher levels of IFN-γ than did CD4+ T cells derived from B6 mice receiving C3H.SW T-BM alone. Furthermore, adoptive transfer of these in vivo generated GVHD CD4+ T cells, without CD8+ T cells, into secondary irradiated B6 recipients induced clinical GVHD characterized by delayed onset, weight loss, diarrhea, and lymphopenia, but without cutaneous inflammation. Histologic examination demonstrated chronic inflammation in the liver and intestinal tract, including epithelial apoptosis. Thymic pathology was dramatic in secondary B6 recipients of GVHD CD4+ T cells, including thymic atrophy, loss of thymic cortex, and infiltration of large amount of tingible macrophages. Taken together, these results demonstrate that donor bone marrow derived, de novo generated CD4+ T cells also contribute to GVHD together with transferred mature CD8+ T cells. Moreover, they suggest that these CD4+ T cells, in concert with alloreactive memory CD8+ T cells that develop during the evolution of GVHD, cause the persistence of acute GVHD and its subsequent progression into chronic GVHD. Thus, donor BM-derived, de novo generated CD4+ T cells are the “Hidden Dragon” of CD8+ T cell-mediated GVHD. Understanding how these CD4+ T cells are generated and regulated will prove to be critical to the prevention and treatment of both acute and chronic GVHD.

Short-Term Ionomycin Exposure Activates Naive Murine T-Cells and Induces a Rapid Phenotypic Shift to Memory T-Cell Status: Potential for Use as a Method To Reduce GvHD Activity of Allogeneic T-Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2182-2182
Author(s):  
Mohammad Hossain ◽  
Cynthia R. Giver ◽  
Ned Waller
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Memory T Cells ◽  
Cell Phenotype ◽  
Naive T Cells ◽  
Memory T Cell ◽  
Naïve T Cells

Abstract We are investigating methods to reduce the graft-versus-host disease (GVHD) potential of donor T-cells while retaining graft-versus-leukemia (GVL) activity in allogeneic HSCT. Previous investigations by our group and others in have shown that naive CD4 T-cells induce severe acute GVHD, while memory CD4 T-cells do not induce GVHD but retain GVL activity in murine transplant models. These findings have led to studies for the development of methods to increase the number of memory T-cells available for transplant. The calcium ionophore, ionomycin, is a T-cell activating agent and mitogen. By increasing intracellular Ca2+ levels, ionomycin is induces T-cell activation through signaling mechanisms including phospholipase C activation, hydrolysis of phosphoinositides, and activation of protein kinase C. Differences in memory and naive T-cell responses to ionomycin have been attributed to resistance of memory T-cells to increases in Ca2+. Memory T-cells lack intracellular Ca2+ stores, and are also resistant to influx of Ca2+. Brief low dose ionomycin exposure (20min, 2μM) of T-cells, leading to increased density of naive T-cells, has previously been exploited as a method for separating memory and naive T-cells by Percoll gradient separation. Since ionomycin exposure induces T-cell activation through native Ca2+ dependent signaling mechanisms, we hypothesized that ionomycin-treated T-cells would shift to an activated/memory T-cell phenotype. Murine splenic T-cells were treated with 1.3μM ionomycin for 4hr. Memory and naive T-cell subsets and activation markers were analyzed by flow cytometry. 75% and 85% of untreated CD4 and CD8 T-cells, respectively, had the CD62L+ naive phenotype. These numbers were dramatically reduced to 7% and 17% after ionomycin exposure, representing a shift to the memory T-cell phenotype. Viability of T-cells was not significantly affected. The majority of remaining CD62L+ naive T-cells expressed activation markers CD25 and CD69. The fraction of CD4+CD25+Foxp3+ regulatory T-cells was also determined by intracellular staining of the transcription factor and co-expression of surface markers. CD4+CD25+Foxp3+ regulatory T-cells represented 4% of untreated CD4 T-cells and 3% of ionomycin-treated CD4 T-cells. While ionomycin has been used for many years in studies of T-cell activation, to our knowledge this is the first demonstration of a rapidly-induced shift of naive T-cells to a memory phenotype. A pilot experiment was conducted testing the GVHD activity of ionomycin-treated splenocytes (SP) in B6→ (B6 × Balb/C)CB6F1 recipients. 5 × 106 T-cell depleted bone marrow cells (TCD-BM) were transplanted along with 10 × 106 treated or untreated SP. Mice that received untreated SP all died from acute GvHD by 34 days after transplant, while all recipients of ionomycin-treated SP survived until the experiement was terminated at day 49 (average weight loss was 25%, data not shown). Continuing experients will refine the dose to further reduce GVHD symptoms and also test GVL activity of the treated cells. Treatment of donor T-cells with ionomycin may represent a clinically applicaple method to engineer donor lymphocyte infusions that are safer for HSCT patients. Figure 1. Survival of CB6F1 recipients after transplant with 5 million B6 TCD-BM and 10 million B6 splenocytes that were either untreated or stimulated ex-vivo with a combination of PMA, ionomycin and brefeldin-A for 4 hours. 5 recipient animals per group. The experiment was terminated at day 49. Figure 1. Survival of CB6F1 recipients after transplant with 5 million B6 TCD-BM and 10 million B6 splenocytes that were either untreated or stimulated ex-vivo with a combination of PMA, ionomycin and brefeldin-A for 4 hours. 5 recipient animals per group. The experiment was terminated at day 49.

scholarly journals T cell populations primed by hapten sensitization in contact sensitivity are distinguished by polarized patterns of cytokine production: interferon gamma-producing (Tc1) effector CD8+ T cells and interleukin (Il) 4/Il-10-producing (Th2) negative regulatory CD4+ T cells.

1996 ◽  
Vol 183 (3) ◽  
pp. 1001-1012 ◽  
Author(s):  
H Xu ◽  
N A DiIulio ◽  
R L Fairchild
Keyword(s):  
T Cells ◽  
Lymph Node ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Langerhans Cells ◽  
Cytokine Production ◽  
Contact Hypersensitivity ◽  
Cell Populations ◽  
Ifn Gamma

Contact hypersensitivity (CHS) is a T cell-mediated response to hapten sensitization of the epidermis. The roles of CD4+ and CD8+ T cells in CHS have remained unclear, however, as studies to define either subset as the T cells mediating CHS have provided conflicting results. The goal of this study was to correlate the in vivo function of CD4+ and CD8+ T cells in CHS with the cytokines produced by each T cell population. Antibody-mediated depletion of CD4+ T cells before sensitization of BALB/c mice with 2,4-dinitrofluorobenzene (DNFB) or oxazolone (Ox) resulted in increased and prolonged CHS responses, indicating CD4+ T cells as negative regulators of the response. Depletion of CD8+ T cells resulted in low or abrogated responses, indicating CD8+ T cells as the effector cells in CHS. Sensitization with DNFB or Ox induced lymph node cell populations of CD8+ T cells producing interferon (IFN)-gamma and no interleukin (Il) 4 or Il-10, and CD4+ T cells producing Il-4 and Il-10 and no or little detectable IFN-gamma. The polarized patterns of cytokine production were stimulated by culture of hapten-primed lymph node cells either on anti-T cell receptor antibody-coated wells or with semipurified Langerhans cells isolated from hapten-sensitized mice. Stimulation of cytokine production during culture of hapten-primed CD4+ or CD8+ T cells with Langerhans cells was hapten specific and restricted to class II or class I major histocompatibility complex, respectively. The induction of the CD4+ and CD8+ T cells producing the polarized patterns of cytokines was not restricted to BALB/c mice, as cells from Ox sensitized C57B1/6 and B10.D2 mice produced the same patterns. Collectively, these results expose the induction of two polarized and functionally opposing populations of T cells by hapten sensitization to induce CHS: IFN-gamma-producing effector CD8+ T cells and Il-4/Il-10-producing CD4+ T cells that negatively regulate the response.

scholarly journals Reduced immune-regulatory molecule expression on human colonic memory CD4 T cells in older adults

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Stephanie M. Dillon ◽  
Tezha A. Thompson ◽  
Allison J. Christians ◽  
Martin D. McCarter ◽  
Cara C. Wilson
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Older Persons ◽  
Age Groups ◽  
T Cell Immunity ◽  
Cd4 T Cell ◽  
Cell Immunity ◽  
Memory Cd4 T Cells

Abstract Background The etiology of the low-level chronic inflammatory state associated with aging is likely multifactorial, but a number of animal and human studies have implicated a functional decline of the gastrointestinal immune system as a potential driver. Gut tissue-resident memory T cells play critical roles in mediating protective immunity and in maintaining gut homeostasis, yet few studies have investigated the effect of aging on human gut T cell immunity. To determine if aging impacted CD4 T cell immunity in the human large intestine, we utilized multi-color flow cytometry to measure colonic lamina propria (LP) CD4 T cell frequencies and immune-modulatory marker expression in younger (mean ± SEM: 38 ± 1.5 yrs) and older (77 ± 1.6 yrs) adults. To determine cellular specificity, we evaluated colon LP CD8 T cell frequency and phenotype in the same donors. To probe tissue specificity, we evaluated the same panel of markers in peripheral blood (PB) CD4 T cells in a separate cohort of similarly aged persons. Results Frequencies of colonic CD4 T cells as a fraction of total LP mononuclear cells were higher in older persons whereas absolute numbers of colonic LP CD4 T cells per gram of tissue were similar in both age groups. LP CD4 T cells from older versus younger persons exhibited reduced CTLA-4, PD-1 and Ki67 expression. Levels of Bcl-2, CD57, CD25 and percentages of activated CD38+HLA-DR+ CD4 T cells were similar in both age groups. In memory PB CD4 T cells, older age was only associated with increased CD57 expression. Significant age effects for LP CD8 T cells were only observed for CTLA-4 expression, with lower levels of expression observed on cells from older adults. Conclusions Greater age was associated with reduced expression of the co-inhibitory receptors CTLA-4 and PD-1 on LP CD4 T cells. Colonic LP CD8 T cells from older persons also displayed reduced CTLA-4 expression. These age-associated profiles were not observed in older PB memory CD4 T cells. The decline in co-inhibitory receptor expression on colonic LP T cells may contribute to local and systemic inflammation via a reduced ability to limit ongoing T cell responses to enteric microbial challenge.

scholarly journals Response of naive antigen-specific CD4+ T cells in vitro: characteristics and antigen-presenting cell requirements.

1992 ◽  
Vol 176 (5) ◽  
pp. 1431-1437 ◽  
Author(s):  
M Croft ◽  
D D Duncan ◽  
S L Swain
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Cd4 Cells ◽  
Peptide Antigen ◽  
Naive T Cells ◽  
Naïve T Cells ◽  
Antigen Presenting

Because of the low frequency of T cells for any particular soluble protein antigen in unprimed animals, the requirements for naive T cell responses in specific antigens have not been clearly delineated and they have been difficult to study in vitro. We have taken advantage of mice transgenic for the V beta 3/V alpha 11 T cell receptor (TCR), which can recognize a peptide of cytochrome c presented by IEk. 85-90% of CD4+ T cells in these mice express the transgenic TCR, and we show that almost all such V beta 3/V alpha 11 receptor-positive cells have a phenotype characteristic of naive T cells, including expression of high levels of CD45RB, high levels of L-selectin (Mel-14), low levels of CD44 (Pgp-1), and secretion of interleukin 2 (IL-2) as the major cytokine. Naive T cells, separated on the basis of CD45RB high expression, gave vigorous responses (proliferation and IL-2 secretion) to peptide antigen presented in vitro by a mixed antigen-presenting cell population. At least 50% of the T cell population appeared to respond, as assessed by blast transformation, entry into G1, and expression of increased levels of CD44 by 24 h. Significant contributions to the response by contaminating memory CD4+ cells were ruled out by demonstrating that the majority of the CD45RB low, L-selectin low, CD44 high cells did not express the V beta 3/V alpha 11 TCR and responded poorly to antigen. We find that proliferation and IL-2 secretion of the naive CD4 cells is minimal when resting B cells present peptide antigen, and that both splenic and bone marrow-derived macrophages are weak stimulators. Naive T cells did respond well to high numbers of activated B cells. However, dendritic cells were the most potent stimulators of proliferation and IL-2 secretion at low cell numbers, and were far superior inducers of IL-2 at higher numbers. These studies establish that naive CD4 T cells can respond vigorously to soluble antigen and indicate that maximal stimulation can be achieved by presentation of antigen on dendritic cells. This model should prove very useful in further investigations of activation requirements and functional characteristics of naive helper T cells.

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