scholarly journals Ixazomib Impairs Dendritic Cell Function and T Cell Proliferation and Affects the Development of GvHD in a Schedule-Dependent Fashion

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1881-1881
Author(s):  
Yuxin Feng ◽  
Austin Goodyke ◽  
Marlee Muilenberg ◽  
Kelli Cole ◽  
Kathleen Cannady ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
T Cell Proliferation ◽  
Group 3 ◽  
Group 2 ◽  
Dc Maturation ◽  
Pro Inflammatory Cytokines ◽  
Group 1

Abstract Background: Targeting T cells alone has yielded limited success in the prevention of graft-versus-host disease (GvHD) following allogeneic blood and marrow transplantation (BMT). Dendritic cells (DCs) play a central role in alloreactivity and therefore represent a suitable target. Proteasome inhibitors (PI), with their ability to inhibit the function and maturation of DC, have prompted investigators to examine their potential role in the prevention of GvHD. The investigational PI, ixazomib (IXZ), dissociates rapidly from 20S and is therefore truly reversible. It is also orally bioavailable. Our aim in this study was to explore its effect on healthy volunteer peripheral blood dendritic and T cells and in a pre-clinical GvHD mouse model. Methods: To characterize the effects of IXZ on healthy volunteer peripheral blood DCs, DCs were isolated using EasySep Pan-DC Pre-Enrichment Cocktail with purity over 90% (STEMCELL Technologies). DCs were then treated with IXZ at different concentrations (10-40nM) for 4 hrs and then stimulated with lipopolysaccharide (LPS) for 16 hrs. After this treatment, DCs were surface stained with antibodies against maturation markers and analyzed by flow cytometry. DC survival was evaluated with 7AAD staining and FACS analysis. To assess the effect of IXZ on the production of pro-inflammatory cytokines, DCs were incubated with IXZ at increasing concentration before or after the addition of LPS. Total pro-inflammatory cytokines in the supernatant of tissue culture were measured using EMD Millipore cytokine arrays. Standard mixed lymphocyte reaction and T cell proliferation assays were used to evaluate T cell function. At a minimum, all experiments were done in triplicate. Unpaired t test was used for statistical analysis. A p-value < 0.05 was considered significant. The B6 → BALB/c pre-clinical GvHD model was adopted to evaluate the effect of IXZ on GvHD development. Mice were transplanted in 3 groups. Group 1 received a lethal dose of total body irradiation (TBI), donor bone marrow (BM) cells, and IXZ, group 2 received TBI, donor BM cells donor splenocytes, and a vehicle, and group 3 received TBI, donor BM cells, donor splenocytes, and IXZ. The dose of BM cells and splenocytes was 5 X 106 each. IXZ was given at 1.5 mg/kg subcutaneously. Two dosing schedules were tested in 2 separate experiments: day-1 and +2 or day +1 and +4. Results: IXZ inhibited the expression of 6 DC maturation markers including CD40, CD54, CD80, CD83, CD86 and CD197 (CCR-7). The inhibition started at a concentration of 10nM and was dose-related. IXZ also decreased the percentage of total DCs simultaneously expressing multiple markers. DCs viability remained unchanged in comparison to control at a concentration of 10nM and dropped to 68% and 43%, on average with concentrations of 20nM and 40nM, respectively. IXZ significantly decreased DC production of IL-6, IL-12, and IL-23 starting at the concentration of 20nM. IL-1β was decreased at the concentration of 40 nM. Importantly, there was no significant change in the cytokine production by DCs when IXZ was added 4 hrs after LPS except for IL-1β which increased at 30nM. Starting at the concentration of 10nM, IXZ dose-dependently inhibited T cell proliferation. At 40nM IXZ abolished T cells. In our in vivo study IXZ improved GvHD scores on days +7 and +11 in group 3 in comparison to group 2 when it was given on days -1 and +2. Conversely, when IXZ was given on day +1 and +4, group 3 mice had higher scores of GvHD and worse survival outcomes when compared to group 2. There was no noticeable drug toxicity in group 1 mice. Conclusion: In summary: 1) IXZ inhibits DC maturation with relative preservation of cell viability and inhibits pro-inflammatory cytokine production in DCs when added before LPS stimulation; 2) IXZ inhibits T-cell proliferation; 3) IXZ affects GvHD development in a schedule-dependent fashion with early administration improving and late administration worsening GvHD. Additional analysis of tissue and serum samples is in progress. These results provide background for careful design of clinical trials using IXZ for the prevention of GvHD. Disclosures Al-Homsi: Millennium Pharmaceuticals: Research Funding.

Hydroxyurea Is Most Suitable for Cytoreduction of AML Prior to CD33/CD3 Bispecific BiTE® Antibody (AMG 330) Therapy: Uncompromised T-Cell Proliferation Ex-Vivo and CD33 Upregulation on AML Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 986-986 ◽  
Author(s):  
Christina Krupka ◽  
Franziska Brauneck ◽  
Felix S Lichtenegger ◽  
Peter Kufer ◽  
Roman Kischel ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Cell Function ◽  
Expression Level ◽  
T Cell Proliferation ◽  
Hl60 Cells ◽  
T Cell Function ◽  
Equity Ownership

Abstract Bispecific T-cell engager (BiTE®) antibodies represent a promising tool for anti-leukemic immunotherapy. The CD19/CD3-bispecific antibody blinatumomab was shown to be active in refractory and relapse patients with B-precursor acute lymphoblastic leukemia (Topp et al, ASCO 2014). Transient, blinatumomab-mediated cytokine release syndrome has been linked to target cell numbers as this phenomenon is predominantly observed within the first treatment cycle. In our previous work, we demonstrated that the bispecific CD33/CD3 BiTE® antibody AMG 330 is able to induce activation and proliferation of residual autologous T-cells and effectively mediates lysis of primary acute myeloid leukemia (AML) cells (Krupka et al, Blood 2014; 123(3):356-65). We hypothesize that in AML patients with high initial leukocyte counts (WBC > 30.000/μl) a cytoreductive phase prior to AMG 330 therapy might be beneficial to reduce the incidence and severity of cytokine mediated toxicity. Ideally, the cytoreductive drug does not impair T-cell function or reduce target antigen expression level. In the current study, we evaluated the effect of cytarabine (20 µM), decitabine (5 µM), azacitidine (1 µM and 5 µM) and hydroxyurea (10 µM and 100 µM) on T-cell proliferation and function in close analogy to potential treatment algorithms for AML. Healthy donor (HD) T-cells were pre-incubated with the cytoreductive drugs for 72 hours. T-cells were CFSE-labeled and co-cultured with either HL60 or MV4-11 cells (effector cell:target (E:T) ratio 1:1) in the presence or absence of AMG 330 (5 ng/ml). After 3 days of co-culture, lysis of HL60 cells and T-cell proliferation was assessed by flow cytometry. Pretreatment of T-cells with cytarabine completely abrogated T-cell function (lysis of HL60 cells: untreated (UT): 96.9% vs 20 µM: 4.2%) and significantly impaired T-cell proliferation (UT: 31.2% vs 20 µM: 4.6%). These findings correlated to data using primary AML samples collected 3 and 6 days after discontinuation of cytarabine treatment. After a 3-day chemotherapy-free interval, we observed no relevant T-cell proliferation and lysis of AML cells upon the addition of AMG 330 to the ex-vivo long-term culture system (lysis of AML cells on day 12: 30%; fold change T-cell expansion 0.9). After a 6-day treatment-free interval, high T-cell proliferation and cytotoxicity against primary AML cells were observed (lysis of AML cells on day 12: 61%; fold change T-cell expansion: 3.1). In contrast to cytarabine, decitabine treatment only marginally impaired T-cell function. Similarly, pre-incubation with azacitidine did not convey a negative effect on T-cell function (lysis of HL60 cells: UT: 100% vs 1 µM: 94.9% vs 5µM: 86.8%; proliferation: UT: 90.9% vs 1 µM: 80% vs 5 µM: 66.8%). Pretreatment with hydroxyurea had the least impact on T-cell performance. It did not impair T-cell function (lysis of HL60 cells: UT: 100% vs 10 µM: 100% vs 100 µM: 100%) and proliferation compared to untreated controls (UT: 92.9% vs 100 µM 90.8% vs 10 µM 92.9%). As we have previously shown that the level of CD33 expression correlates to kinetics of AMG 330-mediated lysis (Krupka et.al, EHA 2014), we analyzed the effect of the cytoreductive agents on CD33 expression level in AML cell lines and primary AML cells. Five AML cell lines (HL60, MV4-11, PL21, OCI-AML3, KG1a) and a primary AML patient sample were cultured in the presence or absence of decitabine (5 µM and 50 µM), azacitidine (1 µM and 5 µM) or hydroxyurea (10 µM and 100 µM) for 72 hours. The change of CD33 expression level was evaluated by flow cytometry (median fluorescence intensity, MFI). No significant changes in CD33 expression level were observed after culture of AML cell lines and primary AML cells with decitabine or azacitidine. In contrast, hydroxyurea upregulated surface expression of CD33 on 2/5 cell lines (HL60 and PL21) in a dose dependent manner (HL 60 MFI Ratio: UT 134.9 vs 10 µM 171.3 vs 100 µM 210; PL21 MFI Ratio: UT 166.9 vs 10 µM 177.9 vs 100 µM 191.8). In summary, we could show that pretreatment with hydroxyurea did not impair T-cell function and proliferation. In addition, we observed an upregulation of CD33 expression on AML cell lines. As the BiTE® technology relies on T-cell function and target antigen expression level, sequential and combinatorial immuno-chemotherapeutic approaches need to address both issues. Our data support the use of hydroxyurea in AML patients that require cytoreduction prior to AMG 330 treatment. Disclosures Krupka: AMGEN Inc.: Research Funding. Kufer:AMGEN Research (Munich): Employment; AMGEN Inc.: Equity Ownership. Kischel:AMGEN Research (Munich): Employment; AMGEN Inc.: Equity Ownership. Zugmaier:AMGEN Inc.: Equity Ownership; AMGEN Research (Munich): Employment. Sinclair:AMGEN Inc.: Employment, Equity Ownership. Newhall:AMGEN Inc.: Employment, Equity Ownership. Frankel:AMGEN Inc.: Employment, Equity Ownership. Baeuerle:AMGEN Research (Munich): Employment; AMGEN Inc.: Equity Ownership. Riethmüller:AMGEN Inc.: Equity Ownership. Subklewe:AMGEN Inc.: Research Funding.

scholarly journals C-Jun Nh2-Terminal Kinase (Jnk)1 and Jnk2 Have Similar and Stage-Dependent Roles in Regulating T Cell Apoptosis and Proliferation

2001 ◽  
Vol 193 (3) ◽  
pp. 317-328 ◽  
Author(s):  
Kanaga Sabapathy ◽  
Tuula Kallunki ◽  
Jean-Pierre David ◽  
Isabella Graef ◽  
Michael Karin ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Interleukin 2 ◽  
Binding Activity ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
T Cell Function ◽  
Thymocyte Apoptosis

Apoptotic and mitogenic stimuli activate c-Jun NH2-terminal kinases (JNKs) in T cells. Although T cells express both JNK1 and JNK2 isozymes, the absence of JNK2 alone can result in resistance to anti-CD3–induced thymocyte apoptosis and defective mature T cell proliferation. Similar defects in thymocyte apoptosis and mature T cell proliferation, the latter due to reduced interleukin 2 production, are also caused by JNK1 deficiency. Importantly, T cell function was compromised in Jnk1+/−Jnk2+/− double heterozygous mice, indicating that JNK1 and JNK2 play similar roles in regulating T cell function. The reduced JNK dose results in defective c-Jun NH2-terminal phosphorylation in thymocytes but not in peripheral T cells, in which nuclear factors of activated T cells (NK-ATs)–DNA binding activity is affected. Thus, JNK1 and JNK2 control similar functions during T cell maturation through differential targeting of distinct substrates.

scholarly journals Coexpression of CD25 and CD27 identifies FoxP3+ regulatory T cells in inflamed synovia

2005 ◽  
Vol 201 (11) ◽  
pp. 1793-1803 ◽  
Author(s):  
Claudia R. Ruprecht ◽  
Marco Gattorno ◽  
Francesca Ferlito ◽  
Andrea Gregorio ◽  
Alberto Martini ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Synovial Fluid ◽  
Regulatory T Cells ◽  
Cell Function ◽  
Effector T Cells ◽  
T Cell Proliferation ◽  
Activated T Cells

A better understanding of the role of CD4+CD25+ regulatory T cells in disease pathogenesis should follow from the discovery of reliable markers capable of discriminating regulatory from activated T cells. We report that the CD4+CD25+ population in synovial fluid of juvenile idiopathic arthritis (JIA) patients comprises both regulatory and effector T cells that can be distinguished by expression of CD27. CD4+CD25+CD27+ cells expressed high amounts of FoxP3 (43% of them being FoxP3+), did not produce interleukin (IL)-2, interferon-γ, or tumor necrosis factor, and suppressed T cell proliferation in vitro, being, on a per cell basis, fourfold more potent than the corresponding peripheral blood population. In contrast, CD4+CD25+CD27− cells expressed low amounts of FoxP3, produced effector cytokines and did not suppress T cell proliferation. After in vitro activation and expansion, regulatory but not conventional T cells maintained high expression of CD27. IL-7 and IL-15 were found to be present in synovial fluid of JIA patients and, when added in vitro, abrogated the suppressive activity of regulatory T cells. Together, these results demonstrate that, when used in conjunction with CD25, CD27 is a useful marker to distinguish regulatory from effector T cells in inflamed tissues and suggest that at these sites IL-7 and IL-15 may interfere with regulatory T cell function.

scholarly journals Effect of Ara-C on T-Cell Function and Flotetuzumab Activity in Pediatric Acute Myeloid Leukemia

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1387-1387
Author(s):  
Anilkumar Gopalakrishnapillai ◽  
Anne Kisielewski ◽  
Ezio Bonvini ◽  
John Muth ◽  
Jan K Davidson-Moncada ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Median Survival ◽  
Cell Function ◽  
Concurrent Administration ◽  
Employment Equity ◽  
Group 3 ◽  
Equity Ownership ◽  
Group 2 ◽  
Pediatric Aml

Acute myeloid leukemia (AML) in children still has a poor prognosis despite the use of maximally intensive chemotherapy associated with severe short-term and long-term side effects. Therefore, development of targeted therapeutics is necessary to improve outcomes in pediatric AML. CD123 (IL3RA) is overexpressed in most of pediatric AML patients (Bras et al., Cytometry B Clin Cytom, 963:134, 2019) and has been pursued as a target for immunotherapy. The efficacy of a dual affinity retargeting agent (CD123xCD3; MGD006 or flotetuzumab), was evaluated in two patient-derived xenograft models of pediatric AML. In addition, concurrent administration of cytarabine with MGD006 was performed to determine the effect of cytarabine on T-cell function and flotetuzumab efficacy. NSG-SGM3 mice were transplanted with 2.5 x 106 cells AML PDX cells. After 18 days post transplant, when human cells were detectable in mouse blood, mice were randomly assigned to one of 8 treatment groups - 1) untreated, 2) T-cells, 3) T-cells with MGD006 (0.5 mg/Kg, Q5d), 4) T-cells with Ara-C (50 mg/Kg, Q5d), 5) T-cells with concurrent administration of Ara-C and MGD006, 6) MDG006 and 7) Ara-C. Mice belonging to groups 2-5 were intravenously injected with 2.0 x 106 human pan T-cells (StemCell Technologies, Cat No. 70024.1), prior to i.p. administration of MGD006 and/or Ara-C. Mice were monitored daily and peripheral blood was collected periodically to evaluate leukemia progression (CD45+CD3-) and T-cell expansion (CD3+CD45+) by flow cytometry. Mice were euthanized when they showed systemic signs of leukemia based on weight and body condition score. The growth of human cell percentage in mouse blood over time was plotted and Kaplan-Meier survival plots were generated. On the day after treatment was terminated, AML cell percentage was greatly reduced, in mice treated with T-cells + MGD006 (Fig. 1, group 3) or T-cells + MGD006 + Ara-C (group 5), compared to the other groups. In addition, exposure to MGD006 (groups 3 and 5) enhanced expansion of adoptively transferred T-cells compared to AML PDX mice receiving T-cells alone (group 2). The ability of MDG006 to enhance the expansion of T-cells in vivo was not attenuated by treatment with Ara-C. Similar results were obtained in a second PDX model (Fig. 2). Taken together, MGD006 enhanced T-cell engraftment with or without Ara-C accompanied by marked reduction in the burden of AML blats in the peripheral blood. As expected, MGD006 in the absence of the effector T-cells (group 6) had minimal effect on reducing leukemic burden or survival (Fig. 3A, B). Mice injected with T-cells alone (group 2) showed 40-day improvement in survival, likely due to the allogeneic effect of T-cells. Regardless, the addition of MGD006 with T-cells (group 3) amplified the effect as mice did not reach experimental endpoints upon study termination at 210 days (Fig. 3B, brown line). Ara-C treatment (group 7) delayed leukemia progression and prolonged median survival by 22.5 days compared to untreated mice (Fig. 4A, B). Consistent with the T-cell expansion induced by Ara-C (Fig. 1), mice treated with T-cells + Ara-C (group 4) survived longer (median survival 180 days) than those treated with Ara-C (group 7) or T-cells alone (group 2) (median survival 116 and 135 days respectively). Mice administered with MGD006 concurrently with Ara-C following T-cell injection (group 5) also did not reach experimental endpoints upon study termination (Fig. 3B, purple line). These mice had 0.1% residual AML cells when the study was terminated (Fig. 3A, solid purple line), which was significantly lower than mice receiving T-cells + MGD006 (group 3, 2% AML cells, P=0.0047). These data demonstrate the activity of MGD006 in the presence of T-cells in prolonging survival in pediatric AML PDX models. Inclusion of Ara-C to this regimen was more efficient in reducing AML burden. Disclosures Bonvini: MacroGenics, Inc.: Employment, Equity Ownership. Muth:MacroGenics, Inc.: Employment, Equity Ownership. Davidson-Moncada:MacroGenics, Inc.: Employment, Equity Ownership.

scholarly journals Steroids Abrogate BiTE® Antibody Construct-Mediated Cytotoxicity in Primary AML Cells

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3940-3940
Author(s):  
Christina Krupka ◽  
Bettina Lindl ◽  
Thomas Köhnke ◽  
Julia Platzer ◽  
Lavinia Pachzelt ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Ex Vivo ◽  
Antibody Therapy ◽  
Antigen Expression ◽  
T Cell Proliferation ◽  
Negative Effect ◽  
Equity Ownership

Abstract Antibody based immunotherapy represents a promising strategy to eliminate chemoresistant cells in acute myeloid leukemia (AML). Clinical experience in acute lymphoblastic leukemia (ALL) has shown a clear correlation of leukemic burden and the occurrence of a cytokine release syndrome (CRS) during treatment with blinatumomab (CD19/CD3 BiTE®). A cytoreductive phase prior to or in combination with antibody therapy might be beneficial to reduce the severity of adverse events like CRS. The latter is often treated with steroids (dexamethasone, DEX) or less commonly, with the IL-6R antibody tocilizumab (TOC). As T-cell proliferation and function are of crucial importance for BiTE® activity (Zugmaier 2015), the effect of the drugs on effector cell function will dictate clinical response to therapy. In this study, we evaluated the influence of cytoreductive- (azacythidine, AZA; decitabine, DEC), and immunmodulatory (DEX and TOC) drugs on antibody-mediated cytotoxicity and T-cell proliferation. A CD33/CD3 BiTE® antibody construct (AMG 330) served as model T-cell recruiting antibody in this study. To address this question we set up the following experimental approaches: AML cells were cocultured with healthy donor (HD) T cells for up to 14 days ex vivo. T cells were either incubated with the specific drug for 3 days prior to coculture or the drugs were simultaneously added to AML-T cell cultures. Drug concentrations were chosen based on published serum concentrations in AML patients and their ex vivo stability in culture, validated by mass spectrometry. BiTE® mediated cytotoxicity and T-cell proliferation were assessed by flow cytometry. Preincubation of T cells with AZA and DEC impaired antibody mediated cytotoxicity of HL60 cells in a concentration dependent manner (% lysis control (ctrl) vs AZA at 1, 5, 10 µM: 99.9 vs 99.2 vs 52.1 vs 28.7, n=7; ctrl vs DEC at 0.2, 2, 5 µM: 98.4 vs 71.3 vs 60.0 vs 50.0, n=3). Similarly, T-cell proliferation was also markedly decreased (fold change (FC) T cells ctrl vs AZA at 1, 5, 10 µM: 2.9 vs 2.8 vs 1.5 vs 0.7; ctrl vs DEC at 0.2, 2, 5 µM: 3.8 vs 3.0 vs 2.3 vs 1.2). For DEX it was shown that incubation of T cells with steroids prior to cocultures had no negative effect on BiTE® mediated cytotoxicity (Brandl 2007). However, as steroids are often used simultaneously with T-cell recruiting immunotherapies, we tested the influence of DEX in combination with AMG 330. The addition of DEX to primary AML-T cell cultures (75 ng/ml) significantly impaired AMG 330 mediated cytotoxicity (% lysis AMG 330 vs AMG 330+DEX day (d) 6: 95.9 vs 47.5, n=9). This correlated to a markedly reduced T-cell proliferation (FC T cells AMG 330 vs AMG 330+DEX d6: 11.2 vs 1.2, n=9). Correspondingly, secretion of IFNγ was also decreased (n=3). Upon discontinuation of DEX an increase in AMG 330 mediated cytotoxicity was observed. Nevertheless, cytotoxicity was still considerably lower compared to control cultures (%lysis AMG 330 vs AMG 330+DEX d9: 95.6 vs 77.0). In contrast to DEX, TOC (110 µg/ml) had no negative effect on T-cell proliferation (FC T cells d6: AMG 330 vs AMG 330+TOC: 42.3 vs 36.9, n=4). Similarly, secretion of IFNγ was not affected through the simultaneous addition of TOC to primary AMG 330 cultures (pg/ml AMG 330 vs AMG 330+TOC d6: 543.9 vs 345.8 n=2). Importantly, drugs might not only interfere with effector cell function but also modulate target antigen expression. As we have previously demonstrated that antigen expression levels influence BiTE® mediated cytotoxicity (Krupka 2016), we analysed the effect of the drugs on CD33 expression. None of the drugs induced a significant up- or downregulation of CD33 on AML celllines as detected by flow cytometry. Hence our data support the notion that these drugs do not modulate antigen expression dependent lysis kinectics. We conclude, that drugs given prior or concomitant to BiTE® therapy have the potential to reduce T-cell proliferation and cytotoxicity. In particular, we observed a negative impact of AZA and DEC when given prior to AML-T cell cocultures. Importantly, even short exposure to DEX led to a significanly reduced T-cell responsiveness. Our data suggest the careful evaluation of concomitant drugs in T-cell recruiting antibody therapies and support the restrictive use of steroids in patients receiving BiTE® antibody therapy. For management of severe CRS, TOC could be considered as a targeted biologic therapy that preserves BiTE®-dependent T cell function. Disclosures Krupka: AMGEN Research Munich: Research Funding. Kufer:AMGEN Research Munich: Employment, Equity Ownership, Patents & Royalties. Kischel:AMGEN Research Munich: Employment, Equity Ownership, Patents & Royalties. Subklewe:AMGEN Research Munich: Research Funding.

scholarly journals Helper and suppressor T-cell function in HIV-infected hemophilia patients

Blood ◽  
1989 ◽  
Vol 74 (1) ◽  
pp. 298-302 ◽  
Author(s):  
R Weimer ◽  
T Schweighoffer ◽  
K Schimpf ◽  
G Opelz
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Cell Subset ◽  
Pokeweed Mitogen ◽  
Suppressor Activity ◽  
T Cell Subset ◽  
Group 3 ◽  
Group 2 ◽  
Hiv Negative

Abstract T-lymphocyte helper and suppressor functions were assessed in 61 hemophilia patients. Twenty one patients were HIV-negative (Group 1), 27 were HIV-positive without having AIDS-related complex (ARC)/AIDS (Group 2), and 13 had ARC/AIDS (Group 3). T, CD4-positive, or CD8- positive T lymphocytes were cocultured with B lymphocytes and pokeweed mitogen for 6 days and immunoglobulin producing cells were assessed in a reverse hemolytic plaque assay. In HIV-infected patients, T cells as well as the CD4-positive T cell subset exhibited reduced helper (P less than .01, Group 2; P less than .0005, Group 3) and elevated suppressor activity (P less than .02, Group 2; P less than .005, Group 3), whereas no significant difference was found between HIV-negative patients and controls. The number of CD4-positive cells was not correlated with CD4 cell function. CD4-positive cells showed no helper activity (less than 10% of control T cells) in 8/11 (73%), but an excessive suppressor activity (greater than 80% suppression of plaque formation) in 6/11 (55%) Group 3 patients. Our results show that defective helper and elevated suppressor functions of T cells in HIV-infected patients are caused not only by a change in the CD4/CD8 cell counts but also by functional abnormalities of the CD4-positive T-cell subset. These abnormal helper and suppressor functions may play a role in the development of the immunodeficiency state of AIDS patients.

scholarly journals Impact of Small Molecules Immunosuppressants on P-Glycoprotein Activity and T-cell Function

2012 ◽  
Vol 15 (3) ◽  
pp. 407 ◽  
Author(s):  
Inés Llaudó ◽  
Linda Cassis ◽  
Joan Torras ◽  
Oriol Bestard ◽  
Marcel·la Franquesa ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Small Molecules ◽  
Cd8 T Cells ◽  
Cell Function ◽  
The Other ◽  
T Cell Subsets ◽  
T Cell Proliferation ◽  
P Glycoprotein

Purpose. P-glycoprotein (Pgp) is a member of the ABC-transporter family that transports substances across cellular membranes acting as an efflux pump extruding drugs out of the cells. Pgp plays a key role on the pharmacokinetics of several drugs. Herein, we have studied the effects of immunosuppressants on Pgp function, assessing rhodamine-123 (Rho123) uptake and efflux in different T-cell subsets. Methods. Different immunosuppressants such as Cyclosporine (CsA), Rapamycin (Rapa) and Tacrolimus (Tac) were used to assess the in vitro effect on Pgp function of main T-cell subsets among healthy volunteers. We measured Rho123 uptake, efflux and kinetic of extrusion in CD4+ and CD8+ subsets by flow cytometry. Antigen-specific memory T-cell responses were assessed by measuring T-cell proliferation and cytokine secretion using an allogeneic mixed lymphocyte reaction. Results. Rho123 uptake in groups treated with CsA and CsA+Rapa was significantly decreased compared to non-treated group and the other immunosupressants in both T cells subsets. Pgp activity was also reduced in CsA and CsA+Rapa compared to the other immunosupressants but it was only significant in the CsA group for CD8+ subset. Kinetic extrusion of Rho123 by Pgp in all groups was faster in CD8+ T cells. All immunosuppressants and the specific Pgp inhibitor PSC833 diminished antigen-primed T-cell proliferation, especially CD8+ T-cell subset. Conclusions. Our data indicate that small molecules immunosuppressants, especially CsA, inhibit Pgp activity and T-cell function being the CD8+ T cells more susceptible to this effect. These findings support the importance of Pgp when designing combined immunosuppressive regimens. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

A Randomized Trial to Evaluate the Impact of Cytokines on Dendritic Cell, T-Cell and T-Cell Function When Mobilizing Normal Donors for Allogeneic Progenitor Cell Transplant: An Interim Analysis.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2854-2854
Author(s):  
Sagar Lonial ◽  
Claire Torre ◽  
Michelle Hicks ◽  
Stephanie Mcmillan ◽  
Amelia A. Langston ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
T Cell Proliferation ◽  
Gm Csf ◽  
T Cell Function ◽  
Hla Dr ◽  
The Impact ◽  
Stem Cell Collection

Abstract Introduction:Optimal cellular immunity following allogeneic HPC transplant represents a balance between the induction of sufficient anti-tumor immunity to eradicate residual cancer cells without the induction of life-threatening GvHD. Dendritic cells are potent APCs with the ability to regulate immune responses. Our group has previously reported that increased numbers of donor DC2 result in inferior EFS following allo BMT (Waller et al, Blood 2001), and that myeloid cytokines used for mobilization modulate the DC content of the auto graft (Lonial et al, BBMT in press). The current trial was designed to evaluate the impact of different cytokine combinations on DC content and T-cell function in normal donors mobilized with either G-CSF or the combination of G-CSF + GM-CSF. Methods: 32 normal donors were randomized to mobilization with G-CSF (7.5 mcg/kg BID) or the combination of GM-CSF (7.5 mcg/kg qAM) + G-CSF (7.5 mcg/kg qPM) until completion of the stem cell collection. Side effects between the 2 regimens were documented using a questionnaire filled out by the donors within 2 weeks of stem cell collection. DC, T-cell, and other cell subsets were measured from the graft using flow cytometry. T-cell function was evaluated by measuring T-cell proliferation in response to PMA, Con A, PHA, and PWM. Cytokines (IL2, IL4, IL10,IL12, TNF, and INF) secreted in response to antigens were measured by ELISA. DC1 (myeloid DC) were defined as Lin-/HLA-DR+/CD11c+/CD123- while DC2 (lymphoid DC) were defined as Lin-/HLA-DR+/CD11c-/CD123+. Results: 28 patients have been successfully collected to date (G-CSF n=15, GM+G-CSF n=13). No donor has failed to mobilize in either group. Among the 15 donors mobilized with G-CSF alone, 5 required multiple days of apheresis as compared with 1 of 13 donors who received GM+G-CSF who required multiple days of apheresis (p=0.06). There was no difference in baseline values of T-cells or DC subsets in the peripheral blood prior to cytokine administration. Grafts collected with GM-CSF+ G-CSF contained significantly fewer DC2 cells and T-cells (median DC2 dose of 2.1 x 10E6/kg and CD3 dose of 197x 10E6/kg) compared with grafts from donors who received G-CSF alone (median DC2 dose of 3.8 x 10E6/kg (p=.01) and CD3 dose of 320 x 10E6/kg (p=0.001)). There was no difference in the content of CD34+ or DC1 in the grafts, nor in the ratio of CD4:CD8 T-cells between grafts collected with the 2 cytokine combinations. T-cell proliferation and cytokine secretion in response to mitogens was not different between grafts collected from the two groups. To date, there is no difference in the frequency of GvHD or relapse between the patients transplanted with the grafts collected from the 2 cytokine cohorts. Conclusions: The addition of GM-CSF to the mobilization regimen results in significantly fewer DC2 cells and T-cells in the blood HPC graft which could impact immune function and GvL following allogeneic HPC transplant. Clinical outcomes and further analysis of TH1/TH2 polarization of T-cells in grafts collected with either G-CSF or G-CSF+GM-CSF are in progress..

scholarly journals Helper and suppressor T-cell function in HIV-infected hemophilia patients

Blood ◽  
1989 ◽  
Vol 74 (1) ◽  
pp. 298-302
Author(s):  
R Weimer ◽  
T Schweighoffer ◽  
K Schimpf ◽  
G Opelz
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Cell Subset ◽  
Pokeweed Mitogen ◽  
Suppressor Activity ◽  
T Cell Subset ◽  
Group 3 ◽  
Group 2 ◽  
Hiv Negative

T-lymphocyte helper and suppressor functions were assessed in 61 hemophilia patients. Twenty one patients were HIV-negative (Group 1), 27 were HIV-positive without having AIDS-related complex (ARC)/AIDS (Group 2), and 13 had ARC/AIDS (Group 3). T, CD4-positive, or CD8- positive T lymphocytes were cocultured with B lymphocytes and pokeweed mitogen for 6 days and immunoglobulin producing cells were assessed in a reverse hemolytic plaque assay. In HIV-infected patients, T cells as well as the CD4-positive T cell subset exhibited reduced helper (P less than .01, Group 2; P less than .0005, Group 3) and elevated suppressor activity (P less than .02, Group 2; P less than .005, Group 3), whereas no significant difference was found between HIV-negative patients and controls. The number of CD4-positive cells was not correlated with CD4 cell function. CD4-positive cells showed no helper activity (less than 10% of control T cells) in 8/11 (73%), but an excessive suppressor activity (greater than 80% suppression of plaque formation) in 6/11 (55%) Group 3 patients. Our results show that defective helper and elevated suppressor functions of T cells in HIV-infected patients are caused not only by a change in the CD4/CD8 cell counts but also by functional abnormalities of the CD4-positive T-cell subset. These abnormal helper and suppressor functions may play a role in the development of the immunodeficiency state of AIDS patients.

Immunosuppressive Regulation of Dendritic Cells and T Cells in Allergic Rhinitis by Semaphorin 3A

2021 ◽  
pp. 194589242110055
Author(s):  
Honghui Liu ◽  
Jinye Xia ◽  
Yu Chen ◽  
Jingang Ai ◽  
Tiansheng Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
Allergic Rhinitis ◽  
Dendritic Cells ◽  
T Cell ◽  
Nasal Mucosa ◽  
T Cell Proliferation ◽  
Obvious Effect ◽  
Healthy Control ◽  
Dc Maturation

Background Semaphrin3A (Sema3A) was found to play a major role in immune regulation in autoimmune diseases and to be of importance in allergic disease. However, the effect of Sema3A on allergic rhinitis (AR) is not fully clear. Objective We sought to elucidate the effects of Sema3A on the regulation of dendritic cells (DCs) and naive CD4+ T cells in AR. Methods The expression of Sema3A in nasal mucosa was measured by immunohistochemical staining and western blotting. Human peripheral blood mononuclear cells were separated by the Ficoll-Hypaque method. DCs and naive CD4+ T cells were purified by magnetic selection. A human Sema3A Fc chimera was added to DCs and naive CD4+ T cells in vitro to evaluate the effect of Sema3A on the function of DCs and T cells. Labeling T cells with CFSE was used to determine cell proliferation. Flow cytometry was used to detect the DC maturation markers (CD40 and CD83) and T helper 17 (Th17) and regulatory T cell (Treg) percentages. ELISA was used to detect the IL10, IL17, IL4, and IFNγ cytokine levels. Results The expression of Sema3A in AR inferior turbinate tissue was lower than that in healthy control tissue. Compared with healthy control DCs, AR DCs showed decreased levels of the DC maturation markers CD40 and CD83 after Sema3A treatment. Furthermore, Sema3A decreased naive CD4+ T cell proliferation in AR. In addition, Sema3A increased the percentage of Tregs but had no obvious effect on Th17 cells. Moreover, Sema3A significantly increased levels of IL10 and IFNγ, and decreased level of IL4, but had no obvious effect on level of IL17. Conclusion AR presented with low expression of Sema3A in nasal mucosa, and Sema3A could decrease DC maturation, T cell proliferation, and Treg polarization.

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