scholarly journals Immunomodulatory Effects of Canine Adipose Tissue Mesenchymal Stem Cell-Derived Extracellular Vesicles on Stimulated CD4+ T Cells Isolated from Peripheral Blood Mononuclear Cells

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Takahiro Teshima ◽  
Yunosuke Yuchi ◽  
Ryohei Suzuki ◽  
Hirotaka Matsumoto ◽  
Hidekazu Koyama
Keyword(s):  
T Cells ◽  
Extracellular Vesicles ◽  
Cd8 T Cells ◽  
Immune Cells ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Immunomodulatory Effects ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

Adipose tissue-derived mesenchymal stem cells (ADSCs) have anti-inflammatory and immunomodulatory characteristics. Many studies have suggested that the immunomodulation of ADSCs is largely mediated by secreted paracrine factors. Various factors are secreted from ADSCs, among which extracellular vesicles are considered to play a major role in the communication between ADSCs and target cells. Several studies have reported the function of canine ADSC-derived extracellular vesicles (cADSC-EVs), but few studies have reported the immunomodulatory effects of cADSC-EVs on immune cells. The purpose of this study was to investigate the effects of cADSC-EVs on in vitro-stimulated CD4+ T cells isolated from peripheral blood mononuclear cells (PBMCs). cADSC-EVs were isolated from cADSCs under naive conditions or primed conditions by tumor necrosis factor-α (TNFα) and interferon-γ (IFNγ). The expression levels of several microRNAs in cADSC-EVs were altered by priming with TNFα and IFNγ. Culturing PBMCs stimulated with concanavalin A in the presence of naive or primed cADSC-EVs inhibited the differentiation of PBMCs and CD4+ T cells and promoted apoptosis of PBMCs. CD4+, CD8+, and CD4+CD8+ T cells were decreased, while CD3+CD4-CD8- T cells were increased. T helper (Th) 1, Th2, Th17, and regulatory T (Treg) cells were analyzed by flow cytometry. cADSC-EVs inhibited the proliferation of Th1 and Th17 cells and enhanced Th2 and Treg cell proliferation. However, CD4+ T cells that had incorporated labeled cADSC-EVs comprised only a few percent of all cells. Therefore, these responses of stimulated CD4+ T cells may be due to not only direct effects of cADSC-EVs but also to indirect effects through interactions between cADSC-EVs and other immune cells. In conclusion, cADSC-EVs exert immunosuppressive effects on stimulated CD4+ T cells in vitro. These findings may be useful for further studies of immune diseases.

171 Preclinical studies support therapeutic application of the leukemic cell-based cancer relapse vaccine DCP-001 in ovarian cancer

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A185-A185
Author(s):  
Maho Nagasawa ◽  
Remco Bos ◽  
Haoxiao Zuo ◽  
Kiave Yune Ho Wang Yin ◽  
Marie-José van Lierop ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
T Cells ◽  
Cd8 T Cells ◽  
Mononuclear Cells ◽  
Leukemic Cell ◽  
Peripheral Blood Mononuclear ◽  
Cancer Relapse ◽  
Blood Mononuclear Cells

BackgroundOvarian cancer (OC) is the gynecological malignancy with the highest mortality due to the late diagnosis of disease and a high rate of relapse following initial therapy. Immunotherapy in combination with standard treatment modalities has emerged as an encouraging treatment approach to surmount this unmet medical need. DCP-001 is a cancer relapse vaccine derived from the DCOne human leukemic cell line and is currently progressing through clinical trials in hematological malignancies. During manufacturing, DCOne cells are shifted towards a mature dendritic cell phenotype, rendering the cells highly immunogenic and providing the basis for DCP-001, which is administered as an intradermal vaccine. DCOne cells express multiple common tumor associated antigens (TAA) such as WT-1, RHAMM, PRAME and MUC-1, which have been documented as potential target antigens in ovarian cancer. This observation suggests that DCP-001 vaccination may also have an anti-tumor effect in OC. To support this hypothesis, we assessed the capacity of DCP-001 to induce immune responses against OC in human peripheral blood mononuclear cells (PBMCs) and a humanized mouse model for OC.MethodsThe effect of DCP-001 on T cells from OC patients or healthy donors was evaluated after a 3 week culture of peripheral blood mononuclear cells (PBMCs) with or without DCP-001. Cytotoxic activity was analysed by specific IFNg production and CD107a expression when these cells were subsequently cultured with the OC cell line SKOV3. The effect of DCP-001 vaccination in vivo was evaluated in humanised NCG mouse subcutaneously engrafted with SKOV3 OC cells. Mice received intra-peritoneal (i.p.) vaccination with DCP-001 either after or prior to SKOV3 engraftment and tumor size was measured to evaluate the efficacy of DCP-001.ResultsIn vitro, DCP-001 was shown to activate both CD4+ as well as CD8+ T cells and to induce formation of memory T cells. Importantly, DCP-001-stimulated CD8+ T cells from OC patients were shown to exert a HLA class I dependent, cytotoxic immune response to OC cells. In vivo, in an ovarian tumor mouse model, significant reduction of tumor growth rate and partial or even complete tumor regressions were observed in mice vaccinated with DCP-001, particularly when administered as relapse vaccine (prior to tumor engraftment), as compared to PBS treated mice.ConclusionsThese pre-clinical in vitro and in vivo results support the potential use of DCP-001 as a cancer relapse vaccine in ovarian cancer, with the aim to reduce disease recurrence following initial standard of care therapy.

scholarly journals OP0033 REGULATORY T CELL CD39 EXPRESSION AS A PREDICTOR OF EARLY REMISSION-INDUCTION WITH METHOTREXATE IN NEW-ONSET RHEUMATOID ARTHRITIS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 18.2-18
Author(s):  
P. Brown ◽  
A. Anderson ◽  
B. Hargreaves ◽  
A. Morgan ◽  
J. D. Isaacs ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
T Cells ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Disease Modifying Therapy ◽  
Blood Mononuclear Cells ◽  
Treatment Naïve ◽  
Disease Modifying ◽  
Pre Treatment

Background:The long term outcomes for patients with rheumatoid arthritis (RA) depend on early and effective disease control. Methotrexate remains the key first line disease modifying therapy for the majority of patients, with 40% achieving an ACR50 on monotherapy(1). There are at present no effective biomarkers to predict treatment response, preventing effective personalisation of therapy. A putative mechanism of action of methotrexate, the potentiation of anti-inflammatory adenosine signalling, may inform biomarker discovery. By antagonism of the ATIC enzyme in the purine synthesis pathway, methotrexate has been proposed to increase the release of adenosine moieties from cells, which exert an anti-inflammatory effect through interaction with ADORA2 receptors(2). Lower expression of CD39 (a cell surface 5-’ectonucleotidase required for the first step in the conversion of ATP to adenosine) on circulating regulatory T-Lymphocytes (Tregs) was previously identified in patients already established on methotrexate who were not responding (DAS28 >4.0 vs <3.0)(3). We therefore hypothesised that pre-treatment CD39 expression on these cells may have clinical utility as a predictor of early methotrexate efficacy.Objectives:To characterise CD39 expression in peripheral blood mononuclear cells in RA patients naïve to disease modifying therapy commencing methotrexate, and relate this expression to 4 variable DAS28CRP remission (<2.6) at 6 months.Methods:68 treatment naïve early RA patients starting methotrexate were recruited from the Newcastle Early Arthritis Clinic and followed up for 6 months. Serial blood samples were taken before and during methotrexate therapy with peripheral blood mononuclear cells isolated by density centrifugation. Expression of CD39 by major immune subsets (CD4+ and CD8+ T-cells, B-lymphocytes, natural killer cells and monocytes) was determined by flow cytometry. The statistical analysis used was binomial logistic regression with baseline DAS28CRP used as a covariate due to the significant association of baseline disease activity with treatment response.Results:Higher pre-treatment CD39 expression was observed in circulating CD4+ T-cells of patients who subsequently achieved clinical remission at 6 months versus those who did not (median fluorescence 4854.0 vs 3324.2; p = 0.0108; Figure 1-A). This CD39 expression pattern was primarily accounted for by the CD4+CD25 high sub-population (median fluorescence 9804.7 vs 6455.5; p = 0.0065; Figure 1-B). These CD25 high cells were observed to have higher FoxP3 and lower CD127 expression than their CD39 negative counterparts, indicating a Treg phenotype. No significant associations were observed with any other circulating subset. A ROC curve demonstrates the discriminative utility of differential CD39 expression in the CD4+CD25 high population for the prediction of DAS28CRP remission in this cohort, showing greater specificity than sensitivity for remission prediction(AUC: 0.725; 95% CI: 0.53 - 0.92; Figure 1-C). Longitudinally, no significant induction or suppression of the CD39 marker was observed amongst patients who did or did not achieve remission over the 6 months follow-up period.Figure 1.Six month DAS28CRP remission versus pre-treatment median fluorescence of CD39 expression on CD4+ T-cells (A); CD25 High expressing CD4+ T-cells (B); and ROC curve of predictive utility of pre-treatment CD39 expression on CD25 High CD4+ T-cells (C).Conclusion:These findings support the potential role of CD39 in the mechanism of methotrexate response. Expression of CD39 on circulating Tregs in treatment-naïve RA patients may have particular value in identifying early RA patients likely to respond to methotrexate, and hence add value to evolving multi-parameter discriminatory algorithms.References:[1]Hazlewood GS, et al. BMJ. 2016 21;353:i1777[2]Brown PM, et al. Nat Rev Rheumatol. 2016;12(12):731-742[3]Peres RS, et al. Proc Natl Acad Sci U S A. 2015;112(8):2509-2514Disclosure of Interests:None declared

CD70 Expression on HTLV-1 Infected T Cells of Carriers and ATL Patients and Its Clinical Significance

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1730-1730
Author(s):  
Izumi Masamoto ◽  
Sawako Horai ◽  
Tomohiro Kozako ◽  
Makoto Yoshimitsu ◽  
Junko Niimoto ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Surveillance Systems ◽  
Peripheral Blood Mononuclear ◽  
Tax Protein ◽  
Infected Cells

Abstract Abstract 1730 Human T-lymphotropic virus type-1(HTLV-1) is the causative agent of adult T cell leukemia/lymphoma (ATL). HTLV-1 infected T cell growth or leukemogenesis in ATL is controlled by various host immune surveillance systems. Among them, CD70 on HTLV-1 infected T cells coupled with CD27 on virus specific cytotoxic T cells has been suggested to play an important role in ATL leukemogenesis. The CD70 molecule is the only known ligand for CD27, a member of the tumor necrosis factor (TNF) receptor superfamily 7. This negative immunoregulatory pathway downregulates cytotoxic T lymphocyte activity against CD70-expressing virus infected cells. In the present study, we examined CD70 expression on primary lymphocytes of HTLV-1 carriers and ATL patients, its relationship with HTLV-1 Tax protein expression, and the effect on CTL induction. CD70 expression was higher on peripheral blood mononuclear cells (PBMCs) of HTLV-1 infected carriers compared with healthy donors (p = 0.021, n = 21, Mann-Whitney U test), and higher in ATL patients compared to carriers (p = 0.045, n = 38, Mann-Whitney U test). CD70 expression may be observed in CD4 T cells, as well as B cells, but not in CD8 T cells or monocytes. CD70 expression in CD4 T cells is related to HTLV-1 infection, because of increased detection of HTLV-1 Tax protein during over night culture of CD70-expressing cells. Experiments using an ATL cell line, in which Tax expression is inducible by doxycycline stimulation, demonstrated enhanced CD70 expression when Tax protein was induced in HTLV-1 infected cells. Anti-CD70 antibody enhanced CD107a mobilization, a marker of recent cytotoxic degranulation, in HTLV-1 Tax specific CTLs in PBMCs from asymptomatic carriers in vitro, suggesting that the CD70/CD27 pathway plays an important role in the immune response to HTLV-1 infection in carriers, as well as ATL patients. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Immunological features that determine the strength of antibody responses to BNT162b2 mRNA vaccine against SARS-CoV-2

2021 ◽  
Author(s):  
Takahiro Kageyama ◽  
Shigeru Tanaka ◽  
Keishi Etori ◽  
Koto Hattori ◽  
Kazusa Miyachi ◽  
...  
Keyword(s):  
T Cells ◽  
Antibody Titer ◽  
Cd8 T Cells ◽  
Healthcare Workers ◽  
Mononuclear Cells ◽  
Antibody Responses ◽  
Peripheral Blood Mononuclear ◽  
Transitional B Cells ◽  
Blood Mononuclear Cells ◽  
Antibody Titers

We analyzed peripheral blood mononuclear cells (PBMCs) of each 20 individuals with a high anti-SARS-CoV-2 antibody titer and a low antibody titer out of 1,774 healthcare workers who received BNT162b2 mRNA vaccine. A higher antibody titer was associated with the frequencies of naive and transitional B cells before vaccination. In addition, fold changes in the frequency of activated CD8+ T cells upon vaccination were correlated with the antibody titers.

Sign in / Sign up

Export Citation Format

Share Document