T cell subsets in the blast cell population in phytohemagglutinin-stimulated peripheral blood in vitro and in rheumatoid arthritis synovial fluid in vivo

Active suppression by T regulatory (Tr) cells plays an important role in the downregulation of T cell responses to foreign and self-antigens. Mouse CD4+ Tr cells that express CD25 possess remarkable suppressive activity in vitro and in autoimmune disease models in vivo. Thus far, the existence of a similar subset of CD25+CD4+ Tr cells in humans has not been reported. Here we show that human CD25+CD4+ Tr cells isolated from peripheral blood failed to proliferate and displayed reduced expression of CD40 ligand (CD40L), in response to T cell receptor–mediated polyclonal activation, but strongly upregulated cytotoxic T lymphocyte–associated antigen (CTLA)-4. Human CD25+CD4+ Tr cells also did not proliferate in response to allogeneic antigen-presenting cells, but they produced interleukin (IL)-10, transforming growth factor (TGF)-β, low levels of interferon (IFN)-γ, and no IL-4 or IL-2. Importantly, CD25+CD4+ Tr cells strongly inhibited the proliferative responses of both naive and memory CD4+ T cells to alloantigens, but neither IL-10, TGF-β, nor CTLA-4 seemed to be directly required for their suppressive effects. CD25+CD4+ Tr cells could be expanded in vitro in the presence of IL-2 and allogeneic feeder cells and maintained their suppressive capacities. These findings that CD25+CD4+ Tr cells with immunosuppressive effects can be isolated from peripheral blood and expanded in vitro without loss of function represent a major advance towards the therapeutic use of these cells in T cell–mediated diseases.

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696 Brentuximab vedotin, a CD30-directed antibody-drug conjugate, selectively depletes activated Tregs in vitro and in vivo

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-sitc2020.0696 ◽

2020 ◽

Vol 8 (Suppl 3) ◽

pp. A738-A738

Author(s):

Bryan Grogan ◽

Reice James ◽

Michelle Ulrich ◽

Shyra Gardai ◽

Ryan Heiser ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Efflux Pump ◽

Apoptotic Cell ◽

T Cell Subsets ◽

Memory Cells ◽

Antibody Drug Conjugate ◽

Selective Depletion

BackgroundRegulatory T cells (Tregs) play an important role in maintaining immune homeostasis, preventing excessive inflammation in normal tissues. In cancer, Tregs hamper anti-tumor immunosurveillance and facilitate immune evasion. Selective targeting of intratumoral Tregs is a potentially promising treatment approach. Orthogonal evaluation of tumor-infiltrating lymphocytes (TILs) in solid tumors in mice and humans have identified CCR8, and several tumor necrosis family receptors (TNFRs), including TNFSFR8 (CD30), as receptors differentially upregulated on intratumoral Tregs compared to normal tissue Tregs and other intratumoral T cells, making these intriguing therapeutic targets.Brentuximab vedotin (BV) is approved for classical Hodgkin lymphoma (cHL) across multiple lines of therapy including frontline use in stage III/IV cHL in combination with doxorubicin, vinblastine, and dacarbazine. BV is also approved for certain CD30-expressing T-cell lymphomas. BV is comprised of a CD30-directed monoclonal antibody conjugated to the highly potent microtubule-disrupting agent monomethyl auristatin E (MMAE).The activity of BV in lymphomas is thought to primarily result from tumor directed intracellular MMAE release, leading to mitotic arrest and apoptotic cell death.The role CD30 plays in normal immune function is unclear, with both costimulatory and proapoptotic roles described. CD30 is transiently upregulated following activation of memory T cells and expression has been linked to highly activated/suppressive IRF4+ effector Tregs.MethodsHere we evaluated the activity of BV on CD30-expressing T cell subsets in vitro and in vivo.ResultsTreatment of enriched T cell subsets with clinically relevant concentrations of BV drove selective depletion of CD30-expressing Tregs > CD30-expressingCD4+ T memory cells, with minimal effects on CD30-expressing CD8+ T memory cells. In a humanized xeno-GVHD model, treatment with BV selectively depleted Tregs resulting in accelerated wasting and robust T cell expansion. The observed differential activity on Tregs is likely attributable to significant increases in CD30 expression and reduced efflux pump activity relative to other T cell subsets. Interestingly, blockade of CD25 signaling prevents CD30 expression on T cell subsets without impacting proliferation, suggesting a link between CD25, the high affinity IL-2 receptor, and CD30 expression.ConclusionsTogether, these data suggest that BV may have an immunomodulatory effect through selective depletion of highly suppressive CD30-expressing Tregs.AcknowledgementsThe authors would like to thank Michael Harrison, PharmD for their assistance in abstract preparation.Ethics ApprovalAnimals studies were approved by and conducted in accordance with Seattle Genetics Institutional Care and Use Committee protocol #SGE-024.

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Early rheumatoid arthritis is associated with a deficit in the CD4+CD25high regulatory T cell population in peripheral blood

Rheumatology ◽

10.1093/rheumatology/kel089 ◽

2006 ◽

Vol 45 (10) ◽

pp. 1210-1217 ◽

Cited By ~ 135

Author(s):

C. A. Lawson ◽

A. K. Brown ◽

V. Bejarano ◽

S. H. Douglas ◽

C. H. Burgoyne ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

T Cell ◽

Cell Population ◽

Early Rheumatoid Arthritis ◽

Regulatory T Cell ◽

Peripheral Blood

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Quantitative assessment of the pool size and subset distribution of cytolytic T lymphocytes within human resting or alloactivated peripheral blood T cell populations.

Journal of Experimental Medicine ◽

10.1084/jem.158.2.571 ◽

1983 ◽

Vol 158 (2) ◽

pp. 571-585 ◽

Cited By ~ 84

Author(s):

A Moretta ◽

G Pantaleo ◽

L Moretta ◽

M C Mingari ◽

J C Cerottini

Keyword(s):

Monoclonal Antibody ◽

T Cells ◽

T Cell ◽

T Lymphocytes ◽

Peripheral Blood ◽

Great Majority ◽

T Cell Subsets ◽

Cytolytic T Lymphocytes ◽

Subset Distribution

In order to directly assess the distribution of cytolytic T lymphocytes (CTL) and their precursors (CTL-P) in the two major subsets of human T cells, we have used limiting dilution microculture systems to determine their frequencies. The two subsets were defined according to their reactivity (or lack thereof) with B9.4 monoclonal antibody (the specificity of which is similar, if not identical, to that of Leu 2b monoclonal antibody). Both B9+ and B9- cells obtained by sorting peripheral blood resting T cells using the fluorescence-activated cell sorter (FACS) were assayed for total CTL-P frequencies in a microculture system that allows clonal growth of every T cell. As assessed by a lectin-dependent assay, approximately 30% of peripheral blood T cells were CTP-P. In the B9+ subset (which represents 20-30% of all T cells), the CTL-P frequency was close to 100%, whereas the B9- subset had a 25-fold lower CTL-P frequency. It is thus evident that 90% and 10% of the total CTL-P in peripheral blood are confined to the B9+ or B9- T cell subsets, respectively. Analysis of the subset distribution of CTL-P directed against a given set of alloantigens confirmed these findings. CTL-P frequencies were also determined in B9+ and B9- subsets derived from T cells that had been activated in allogenic mixed leucocyte cultures (MLC). Approximately 10% of MLC T cells were CTL-P. This frequency was increased 3.5-fold in the B9+ subset, whereas the B9- subset contained only a small, although detectable number of CTL-P. Moreover, the great majority of the (operationally defined) CTL-P in MLC T cell population were found to be directed against the stimulating alloantigens, thus indicating a dramatic increase in specific CTL-P frequencies following in vitro stimulation in bulk cultures.

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Analysis of T cell subsets present in the peripheral blood and synovial fluid of reactive arthritis patients

Annals of the Rheumatic Diseases ◽

10.1136/ard.57.2.100 ◽

1998 ◽

Vol 57 (2) ◽

pp. 100-106 ◽

Cited By ~ 11

Author(s):

H. Beacock-Sharp ◽

J. L Young ◽

J S H. Gaston

Keyword(s):

T Cell ◽

Synovial Fluid ◽

Peripheral Blood ◽

Reactive Arthritis ◽

T Cell Subsets

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Tofacitinib Suppresses Several JAK-STAT Pathways in Rheumatoid Arthritis In Vivo and Baseline Signaling Profile Associates With Treatment Response

Frontiers in Immunology ◽

10.3389/fimmu.2021.738481 ◽

2021 ◽

Vol 12 ◽

Author(s):

Maaria Palmroth ◽

Krista Kuuliala ◽

Ritva Peltomaa ◽

Anniina Virtanen ◽

Antti Kuuliala ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

T Cells ◽

Treatment Response ◽

Peripheral Blood ◽

Janus Kinase ◽

Cytokine Signaling ◽

Stat3 Phosphorylation ◽

Stat Pathway

ObjectiveCurrent knowledge on the actions of tofacitinib on cytokine signaling pathways in rheumatoid arthritis (RA) is based on in vitro studies. Our study is the first to examine the effects of tofacitinib treatment on Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathways in vivo in patients with RA.MethodsSixteen patients with active RA, despite treatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), received tofacitinib 5 mg twice daily for three months. Levels of constitutive and cytokine-induced phosphorylated STATs in peripheral blood monocytes, T cells and B cells were measured by flow cytometry at baseline and three-month visits. mRNA expression of JAKs, STATs and suppressors of cytokine signaling (SOCS) were measured from peripheral blood mononuclear cells (PBMCs) by quantitative PCR. Association of baseline signaling profile with treatment response was also investigated.ResultsTofacitinib, in csDMARDs background, decreased median disease activity score (DAS28) from 4.4 to 2.6 (p < 0.001). Tofacitinib treatment significantly decreased cytokine-induced phosphorylation of all JAK-STAT pathways studied. However, the magnitude of the inhibitory effect depended on the cytokine and cell type studied, varying from 10% to 73% inhibition following 3-month treatment with tofacitinib. In general, strongest inhibition by tofacitinib was observed with STAT phosphorylations induced by cytokines signaling through the common-γ-chain cytokine receptor in T cells, while lowest inhibition was demonstrated for IL-10 -induced STAT3 phosphorylation in monocytes. Constitutive STAT1, STAT3, STAT4 and STAT5 phosphorylation in monocytes and/or T cells was also downregulated by tofacitinib. Tofacitinib treatment downregulated the expression of several JAK-STAT pathway components in PBMCs, SOCSs showing the strongest downregulation. Baseline STAT phosphorylation levels in T cells and monocytes and SOCS3 expression in PBMCs correlated with treatment response.ConclusionsTofacitinib suppresses multiple JAK-STAT pathways in cytokine and cell population specific manner in RA patients in vivo. Besides directly inhibiting JAK activation, tofacitinib downregulates the expression of JAK-STAT pathway components. This may modulate the effects of tofacitinib on JAK-STAT pathway activation in vivo and explain some of the differential findings between the current study and previous in vitro studies. Finally, baseline immunological markers associate with the treatment response to tofacitinib.

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The Transcriptional Differences of Avian CD4+CD8+ Double-Positive T Cells and CD8+ T Cells From Peripheral Blood of ALV-J Infected Chickens Revealed by Smart-Seq2

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.747094 ◽

2021 ◽

Vol 11 ◽

Author(s):

Manman Dai ◽

Li Zhao ◽

Ziwei Li ◽

Xiaobo Li ◽

Bowen You ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Signaling Pathway ◽

Cell Population ◽

Peripheral Blood ◽

T Cell Response ◽

T Cell Subsets ◽

High Expression ◽

Receptor Interaction ◽

Double Positive

It is well known that chicken CD8+ T cell response is vital to clearing viral infections. However, the differences between T cell subsets expressing CD8 receptors in chicken peripheral blood mononuclear cells (PBMCs) have not been compared. Herein, we used Smart-Seq2 scRNA-seq technology to characterize the difference of chicken CD8high+, CD8high αα+, CD8high αβ+, CD8medium+, and CD4+CD8low+ T cell subsets from PBMCs of avian leukosis virus subgroup J (ALV-J)-infected chickens. Weighted gene co-expression network analysis (WGCNA) and Trend analysis revealed that genes enriched in the “Cytokine–cytokine receptor interaction” pathway were most highly expressed in the CD8high αα+ T cell population, especially T cell activation or response-related genes including CD40LG, IL2RA, IL2RB, IL17A, IL1R1, TNFRSF25, and TNFRSF11, suggesting that CD8high αα+ T cells rather than other CD8 subpopulations were more responsive to ALV-J infections. On the other hand, genes involved in the “FoxO signaling pathway” and “TGF-beta signaling pathway” were most highly expressed in the CD4+CD8low+ (CD8low+) T cell population and the function of CD4+CD8low+ T cells may play roles in negatively regulating the functions of T cells based on the high expression of CCND1, ROCK1, FOXO1, FOXO3, TNFRSF18, and TNFRSF21. The selected gene expressions in CD8+ T cells and CD4+CD8low+ double-positive T cells confirmed by qRT-PCR matched the Smart-Seq2 data, indicating the reliability of the smart-seq results. The high expressions of Granzyme K, Granzyme A, and CCL5 indicated the positive response of CD8+ T cells. Conversely, CD4+CD8+ T cells may have the suppressor activity based on the low expression of activation molecules but high expression of T cell activity suppressor genes. These findings verified the heterogeneity and transcriptional differences of T cells expressing CD8 receptors in chicken PBMCs.

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