Dynamics of Adaptive Immune Cell and NK Cell Subsets in Patients With Ankylosing Spondylitis After IL-17A Inhibition by Secukinumab

Background: Anti-IL-17A therapy is generally effectively applied in patients with Ankylosing Spondylitis (AS) to achieve and maintain remission. However, the influence of anti-IL-17A on the composition of the immune system is not apparent. Our prospective study was to explore the changes in immune imbalance regarding T cell, B cell and natural killer (NK) cell subsets after secukinumab treatment in AS patients.Methods: Immune cell distribution of 43 AS patients treated with secukinumab for 12 weeks and 47 healthy controls (HC) were evaluated. Flow cytometry using monoclonal antibodies against 25 surface markers was accomplished to explore the frequencies of lineage subsets. The differences between HC, AS pre-treatment, and post-treatment were compared using the paired Wilcoxon test, Mann-Whitney U test, and ANOVA.Results: AS patients had altered immune cell distribution regarding T cell and B cell subsets. Apart from activated differentiation of CD4+ T cell, CD8+ T cell and B cell, higher levels of cytotoxic T (Tc) two cells and Tc17 cells were noted in AS patients. We confirmed that helper T (Th) one cell became decreased; however, Th17 cells and T follicular helper (Tfh) 17 cells went increased in AS. After 12 weeks of secukinumab therapy, CRP and ASDAS became significantly decreased, and meanwhile, the proportions of Th1 cells, Tfh17 cells and classic switched B cells were changed towards those of HC. A decreased CRP was positively correlated with a decrease in the frequency of naïve CD8+ T cells (p = 0.039) and B cells (p = 0.007) after secukinumab treatment. An elevated level of T cells at baseline was detected in patients who had a good response to secukinumab (p = 0.005).Conclusion: Our study confirmed that AS patients had significant multiple immune cell dysregulation. Anti-IL-17A therapy (Secukinumab) could reverse partial immune cell imbalance.

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Teriflunomide treatment reduces B cells in patients with MS

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000403 ◽

2017 ◽

Vol 4 (6) ◽

pp. e403 ◽

Cited By ~ 15

Author(s):

Ilaria Gandoglia ◽

Federico Ivaldi ◽

Alice Laroni ◽

Federica Benvenuto ◽

Claudio Solaro ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Immune Cell ◽

Nk Cell ◽

Detectable Effect ◽

Open Label ◽

Regulatory B Cell ◽

Cell Numbers ◽

B Cell Subsets

Objective:To study the immunomodulatory effect of teriflunomide on innate and adaptive immune cell populations through a pilot, open-label, observational study in a cohort of patients with relapsing-remitting MS.Methods:Blood lymphocytes were isolated from 10 patients with MS before and after 3 or 12 months of treatment. Adaptive and innate immune cell subsets were analyzed by flow cytometry as follows: B cells (memory, regulatory, and mature subsets), T cells (effector and regulatory subsets), and natural killer (NK) cells (CD56dim and CD56bright subsets).Results:Our results show that teriflunomide significantly reduces absolute counts of total CD19+ B cells and mature and regulatory B-cell subsets. T cells were affected to a lesser extent, with a trend in reduction of absolute counts for both T effector CD4+ cells (Th1, Th17 and Th1/17) and T regulatory CD8+ and CD4+ cells. Teriflunomide had no detectable effect on NK-cell numbers.Conclusions:In our small cohort, teriflunomide treatment affects mainly and significantly on B-cell numbers, while having a milder effect on T-cell numbers. Larger cohorts are necessary to confirm these findings and understand the effect of teriflunomide on the functionality of these cells.

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POS0003 RITUXIMAB THERAPY IN SYSTEMIC LUPUS ERYTHEMATOSUS – TRANSIENT EFFECTS ON AGE ASSOCIATED B-CELLS

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-eular.2366 ◽

2021 ◽

Vol 80 (Suppl 1) ◽

pp. 203.1-204

Author(s):

F. Faustini ◽

N. Sippl ◽

R. Stålesen ◽

K. Chemin ◽

I. Gunnarsson ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

T Cell Subsets ◽

Cd4 Cells ◽

Helper Cells ◽

B Cell Subsets ◽

Anti Cd20

Background:Immune system’s abnormalities in SLE involve several subsets of the B-cell compartment, including double negative B-cells (DN) and CD11c+CD21- B cells (also referred to as ABC-age associated B cells), which are expanded in the disease. ABC cells are also known to interact with T helper cells, T follicular and peripheral helper cells (1). Rituximab, a chimeric anti- CD20 antibody, depleting B cells, is commonly used off-label as treatment for SLE patients, especially in lupus nephritis. Little is known on the impact of B-cell depletion on such B-cell subsets and on B-T-cell interactions.Objectives:to investigate the effects of rituximab (RTX) on the frequencies of double negative B-cell subsets and CD11c+CD21- ABC cells and as well as T follicular helper (TFH, CXCR5+ PD-1+) and T peripheral helper (TPH, PD-1high) CD4+ T-cell subsets.Methods:15 SLE patients, starting RTX and followed longitudinally up to two years, were analyzed for lymphocyte subsets using multicolor flow cytometry. Cryopreserved PBMC were thawed and stained at the same time together with one buffy coat. Around 1 x 106 PBMC for each panel were labeled and further stained with fluorescent antibodies for B and T-cell markers. For the B-cell panel, PBMC were stained with anti-CD3, CD14, CD16, CD19, IgD, CD27, CD38, CD11c, CD21 and in some samples with anti-CXCR5 antibodies. For the T-cell panel, PBMC were labeled with anti-CD16, CD14, CD19 and CD3, CD4, CD8, PD-1, CCR7, CXCR5, CD45RA antibodies. All patients fulfilled the ACR 1982 classification criteria for SLE. Cellular changes were analyzed in the context of clinical information.Results:in the present cohort, the SLE patients were mainly female (86.6%) and of median age of 36.7 (29.8-49.4) with a disease duration of 6.1(1.6-11.8) years, and active disease with SLEDAI-2K at baseline 12.0 (8.0-16.0). The frequency of age-associated B cells (ABCs; CD27-IgD-CD11c+ CD21-) decreased by 13% (p=0.03) in the first two to four months after rituximab start, while globally the DN (IgD-CD27-) B cells transiently increased by around 3% (p=0.15) at the first follow-up. This increase could not be attributed to the DN1 (CXCR5+CD11c-) or DN2 (CXCR5-CD11c+) subsets but to the CD11c-CXCR5- DN (DN3) B cells (increase= 6.7%, p=0.03). In parallel, T effector cells (CCR7- CD45RA+) and TEMRA (CD45RA+ CCR7-) frequencies increased after first follow up in both CD4+ and CD8+ T cells. The frequency of TFH (CXCR5+ PD-1+) cells did not change after rituximab, however a decrease of PD-1high CD4+ cells was observed in most patients, although not significant, after 2-4 month of treatment. In most patients the frequency of PD-1high CD4+ cells either reduce or stay the same after RTX treatment (reduction= 0.53, p=0.28). After 11-15 months of RTX treatment the frequency of PD-1high CD4+ T cell reduces by a -0.5% in comparison to 2-4 months (p=0.039). The SLEDAI at baseline did not correlate with the frequency of PD-1high CD4+ T cells (r=0.03, p=0.9).Conclusion:the importance of T cell - B cell interactions in SLE pathogenesis was recently strengthened by the identification of the lymphocyte subsets TFH/TPH and ABCs respectively. Here, in the context of rituximab treated SLE, we could detect a reduction in the frequencies of both ABCs and PD-1high T cells after treatment with rituximab, while the DN3 and effector memory T cells frequencies increased. Our data suggests that anti-CD20 mediated B-cell depletion affects both B-cell and T-cell subsets frequencies, and that monitoring these specific cell subsets may be clinically relevant.References:[1]Bocharnikov AV, Keegan J, Wacleche VS, Cao Y, Fonseka CY, Wang G, et al. PD-1hiCXCR5- T peripheral helper cells promote B cell responses in lupus via MAF and IL-21. JCI insight. 2019;4(20)Disclosure of Interests:Francesca Faustini Speakers bureau: More than two years ago and not in relation to any aspect of the present research, Natalie Sippl: None declared, Ragnhild Stålesen: None declared, Karine Chemin: None declared, Iva Gunnarsson: None declared, Vivianne Malmström: None declared.

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Selective B cell depletion upon intravenous infusion of replication-incompetent anti-CD19 CAR lentivirus

10.1101/2020.05.15.098335 ◽

2020 ◽

Cited By ~ 1

Author(s):

Craig M. Rive ◽

Eric Yung ◽

Lisa Dreolini ◽

Daniel J. Woodsworth ◽

Robert A. Holt

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Peripheral Blood ◽

Immune Cell ◽

Wild Type ◽

Immune Cell Subsets ◽

Car T

AbstractAnti-CD19 CAR-T therapy for B cell malignancies has shown clinical success, but a major limitation is the logistical complexity and high cost of manufacturing autologous cell products. Direct infusion of viral gene transfer vectors to initiate in vivo CAR-T transduction, expansion and anti-tumor activity could provide an alternative, universal approach for CAR-T and related immune effector cell therapies that circumvents ex vivo cell manufacturing. To explore the potential of this approach we first evaluated human and murine CD8+ T cells transduced with VSV-G pseudotyped lentivectors carrying an anti-CD19CAR-2A-GFP transgene comprising either an FMC63 (human) or 1D3 (murine) anti-CD19 binding domain. To evaluate CD19 antigen-driven CAR-T proliferation in vitro we co-cultured transduced murine T cells with an excess of irradiated splenocytes and observed robust expansion over a 9 week period relative to control T cells transduced with a GFP transgene (mean fold expansion +/- SD: ID3-CD19CAR-GFP modified T cells, 12.2 +/- 0.09 (p < 0.001); FMC63-CD19CAR-GFP modified T cells 8.8 +/- 0.03 (p < 0.001). CAR-T cells isolated at the end of the expansion period showed potent B cell directed cytolytic activity in vitro. Next, we administered approximately 20 million replication-incompetent lentiviral particles carrying either ID3-CD19CAR-GFP, FMC63-CD19CAR-GFP, or GFP-only transgene to to wild-type C57BL/6 mice by tail vein infusion and monitored the dynamics of immune cell subsets isolated from peripheral blood at weekly intervals. We saw emergence of a persistent CAR-transduced CD3+ T cell population beginning week 3-4 that reaching a maximum of 13.5 +/- 0.58 % (mean +/- SD) and 7.8 +/- 0.76% of the peripheral blood CD3+ T cell population in mice infused with ID3-CD19CAR-GFP lentivector or FMC63-CD19CAR-GFP lentivector, respectively, followed by a rapid decline, in each case of, the B cell content of peripheral blood. Complete B cell aplasia was apparent by week 5 and was sustained until the end of the protocol (week 8). None of these changes were observed in mice infused with GFP-only control lentivector, and significant CAR positive populations were not observed within other immune cell subsets, including macrophage, natural killer, or B cells. Within the T cell compartment, CD8+ effector memory cells were the predominant CAR-positive subset. Modest weight loss of 5.5 +/- 2.97 % (mean +/- SD) observed in some animals receiving an anti-CD19CAR-GFP transgene during the protocol. These results indicate that direct IV infusion of lentiviral particles carrying an anti-CD19 CAR transgene can transduce T cells that then fully ablate endogenous B cells in wild type mice. Based on these results it may be useful to further explore, using currently available vectors, the feasibility of systemic gene therapy as a modality for CAR-T intervention.

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B Cell With Regulatory Function Are Enriched Within Transitional and IgM Memory B Cell Subsets In Healthy Donors But Are Reduced and Functionally Impaired In Patients With Chronic Graft-Versus-Host Disease

Blood ◽

10.1182/blood.v122.21.4478.4478 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4478-4478

Author(s):

Anushruti Sarvaria ◽

Ahmad Khoder ◽

Abdullah Alsuliman ◽

Claude Chew ◽

Takuya Sekine ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Cd4 T Cells ◽

Memory B Cells ◽

Regulatory Function ◽

Healthy Controls ◽

Transitional B Cells ◽

B Cell Subsets

The immunosuppressive function of IL10 producing regulatory B cells (Bregs) has been shown in several murine models of inflammation and autoimmune disease. However, there is a paucity of data regarding the existence of an equivalent regulatory B cell subset in healthy individuals and their potential role in the pathogenesis of chronic graft-versus-host disease (cGVHD) remains unknown. Here, we examined the functional regulatory properties of peripheral blood (PB)-derived human B cell subsets from healthy individuals. In addition, we carried out studies to explore their role in cGVHD, using B cells from patients following allogeneic stem cell transplantation (HSCT). We first determined whether human IL-10 producing B cells are enriched within any othe previously described human B cell subsets: CD19+IgM+CD27+ IgM memory, CD19+IgM-CD27+ switched memory, CD19+IgM+CD27- naive, and and transitional CD19+CD24hiCD38hi. Following in vitro stimulation with CD40 ligand, the majority of IL-10 producing B cells were found within the CD24hiCD38hi transitional and CD19+IgM+CD27+B cell subsets. We next assessed the regulatory properties of the PB-derived B cell subsets, by sort-purifying IgM memory (CD19+IgM+CD27+), switched memory (CD19+IgM-CD27+), naïve (CD19+IgM+CD27-) and transitional (CD19+CD24hiCD38hi) B cells from healthy controls, and cultured them 1:1 with autologous magnetic-bead purified CD4+ T cells. CD3/CD28 stimulated CD4+ T cells cultured with either CD19+IgM+CD27- naïve or CD19+IgM-CD27+ switched memory B cells proliferated to the same extent and produced equivalent amounts of IFN-γ to cultures containing CD4+ T cells alone. In contrast, culture of CD4+ T cells with IgM memory and transitional B cells significantly suppressed CD4+ T cell proliferation [median percent proliferating CD4+ T cells 52.5%; (33%-75%)] and 51% (25%-63%)], respectively when compared with CD3/CD28 stimulated CD4+ T cells (positive control) [89.5% (75%-92%], p=0.0001. The inhibitory effect of IgM memory and transitional B cells on CD4+ T cell proliferation was cell dose dependent with the highest suppression observed at a ratio of 1:1. These data suggest that human PB transitional and IgM memory B cells are endowed with regulatory function. We next examined if the in vitro suppressive effect of transitional and IgM memory B cells is mediated by regulatory T cells (Tregs). For this purpose, CD4+ T cells were depleted of CD127lo CD25hi CD4+ T cells by magnetic cell purification. B cell subsets were cultured with CD3/CD28 stimulated CD4+ CD25- T cells at a ratio of 1:1. IgM memory and transitional B cells were able to significantly suppress the proliferation and Th1 cytokine response by CD4+ CD25- T cells compared to cultures containing CD4+ CD25-T cells alone, indicating that the suppressive activity of Bregs is independent of Tregs. To further understand the underlying mechanims though which Bregs exert T-cell suppression, we used antibody blockade experiments and showed that this suppressive effect was mediated partially via the provision of IL-10, but not TGF-ß. Using transwell experiments, we further determined that the suppressive function of Bregs is also partly dependent on direct T cell/B cell contact. We next assessed whether the activity of Breg cells might be altered in patients with cGVHD. B cells from patients with cGVHD were refractory to CD40 stimulation and produced less IL-10 when compared to patients without cGVHD post-SCT and healthy controls, [1.02% (0.22-2.26) vs.1.72% (0.8-5.52) vs. 2.16 (1.3- 5.6), p=0.001]. Likewise, the absolute number of IL-10 producing B cells was significantly lower in cGvHD patients compared to patients without cGVHD and healthy controls (p=0.007), supporting both a qualitative and quantitative defect in IL-10 producing B cells in cGvHD. Our combined studies provide important new data defining the phenotype of B cell populations enriched in regulatory B cells in healthy humans and provide evidence for a defect in the activity of such cells in patients with cGVHD post-SCT. In association with previous reports showing defects in Treg cell activity in GVHD, our results suggest the existence of a broad range of deficiencies in immune regulatory cell function in cGvHD patients. * Both Anushruti Sarvaria and Ahmad K contributed equally. Disclosures: No relevant conflicts of interest to declare.

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Functional Evaluation of Activation-dependent Alterations in the Sialoglycan Composition of T Cells

Journal of Biological Chemistry ◽

10.1074/jbc.m113.523753 ◽

2013 ◽

Vol 289 (3) ◽

pp. 1564-1579 ◽

Cited By ~ 13

Author(s):

Yuko Naito-Matsui ◽

Shuhei Takada ◽

Yoshinobu Kano ◽

Tomonori Iyoda ◽

Manabu Sugai ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

T Cell Activation ◽

Cell Activation ◽

Immune Cell ◽

Cell Interactions ◽

Functional Evaluation ◽

Activated T Cells

Sialic acids (Sias) are often conjugated to the termini of cellular glycans and are key mediators of cellular recognition. Sias are nine-carbon acidic sugars, and, in vertebrates, the major species are N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc), differing in structure at the C5 position. Previously, we described a positive feedback loop involving regulation of Neu5Gc expression in mouse B cells. In this context, Neu5Gc negatively regulated B-cell proliferation, and Neu5Gc expression was suppressed upon activation. Similarly, resting mouse T cells expressed principally Neu5Gc, and Neu5Ac was induced upon activation. In the present work, we used various probes to examine sialoglycan expression by activated T cells in terms of the Sia species expressed and the linkages of Sias to glycans. Upon T-cell activation, sialoglycan expression shifted from Neu5Gc to Neu5Ac, and the linkage shifted from α2,6 to α2,3. These changes altered the expression levels of sialic acid-binding immunoglobulin-like lectin (siglec) ligands. Expression of sialoadhesin and Siglec-F ligands increased, and that of CD22 ligands decreased. Neu5Gc exerted a negative effect on T-cell activation, both in terms of the proliferative response and in the context of activation marker expression. Suppression of Neu5Gc expression in mouse T and B cells prevented the development of nonspecific CD22-mediated T cell-B cell interactions. Our results suggest that an activation-dependent shift from Neu5Gc to Neu5Ac and replacement of α2,6 by α2,3 linkages may regulate immune cell interactions at several levels.

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The Role of B and T Lymphocytes in Recurrent Acquired Thrombotic Thrombocytopenic Purpura.

Blood ◽

10.1182/blood.v114.22.3521.3521 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3521-3521

Author(s):

Mariagabriella Mariani ◽

Andrea Cairo ◽

Roberta Palla ◽

Luca Andrea Lotta ◽

Andrea Rovati ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Cellular Immunity ◽

T Cell Subsets ◽

Surface Markers ◽

Thrombocytopenic Purpura ◽

B Cell Subsets

Abstract Abstract 3521 Poster Board III-458 Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening disease characterized by thrombocytopenia, microangiopathic haemolytic anemia and widespread microvascular thrombosis, resulting in multiorgan ischemia. Acquired TTP, which accounts for approximately 95% of cases, can be either associated to anti ADAMTS13 autoantibodies or secondary to a number of associated conditions (tumors, organ transplantation, use of drugs, pregnancy). There are several key questions that remain unanswered, including the importance of cellular immunity in immunomediated TTP, and the search for laboratory markers that predict disease relapse, an event that occurs in 20% to 50% of patients who survive the acute initial episode. Since alterations of peripheral B and T cell subsets in patients with autoimmune diseases (i.e. rheumatoid arthritis and systemic lupus erythematous) are well established, the aim of this study was to analyze the role of B and T cells in acquired TTP and during its recurrence. Methods 36 healthy controls and 36 consecutive patients affected by acquired TTP during remission (defined as the maintenance of normalization of clinical and laboratory data for at least 30 days after the last plasma therapy following the resolution of the last acute episode) were characterized by flow cytometry for the quantification of: - different peripheral B cell subsets, using labeled surface markers anti-CD19-PerCP, anti-IgD-PE, anti-IgM-FITC, anti-CD27-APC, anti-CD38-FITC; - different peripheral T cell subsets, using labeled surface markers anti-CD3-FITC, anti-CD4-PE, anti-CD8-APC, anti-CD25-FITC. For Treg cell quantification (only 17 patients were analyzed), anti-CD3-PerCP, anti-CD4-FITC, anti-CD25-PE and the intracellular marker FoxP3 were used. Patients were classified in two subgroups: those who developed at least two episodes of TTP (n=19, with recurrence) and those who experienced a single episode only and no relapse during at least one year of retrospective observational time (n=17). ADAMTS13 activity was measured by residual collagen binding assay (Gerritsen et al, Thromb Haemost 1999). The presence of anti-ADAMTS13 IgG was evaluated by Western blotting and ELISA assays, using recombinant ADAMTS13 protein as antigen and patients' plasma as a source of antibody. The presence of anti-ADAMTS13 IgA, IgM, IgG subclasses (IgG1, 2, 3, 4) were evaluated by ELISA assays. For continuous variables, differences between controls and patients and between patients with or without recurrence were evaluated by the t-test; for discrete variables, by the chi square test. P values smaller than 0.05 were considered statistically significant. Analyses were performed using the SPSS package version 17.0. Results 1) TTP patients had an increased number of CD19+ B cells (mean ± SD 13% ± 5) compared with the control group (10% ± 3, p=0.001). No difference was observed in T cells subsets. 2) The results of the characterization of the two groups of patients (with and without recurrence) are reported in the table. Patients with and without recurrence did not differ either in the amount of Treg FoxP3 or in the presence of IgA, IgM and IgG subclasses. Discussion The increased B cell numbers in acquired TTP indicates an enhanced activation of cellular immunity. Analysis of B cell subsets, particularly of memory B cells, and of T cells CD24+CD25+ during remission might provide information on the likelihood of recurrence in TTP. In conclusion, in recurrent TTP patients the higher amount of B cells might result in persistent autoantibodies production whilst the decreased level of T cells CD4+CD25+ may lead to a decreased inhibition of autoreactive T cells. These findings may explain the higher level of recurrence in these patients. Disclosures: Peyvandi: Archemix Corporation: Consultancy.

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A Single-Cell Transcriptome Profiling of Anterior Kidney Leukocytes From Nile Tilapia (Oreochromis niloticus)

Frontiers in Immunology ◽

10.3389/fimmu.2021.783196 ◽

2021 ◽

Vol 12 ◽

Author(s):

Liting Wu ◽

Along Gao ◽

Lan Li ◽

Jianlin Chen ◽

Jun Li ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Single Cell ◽

Nile Tilapia ◽

Immune Cell ◽

Cell Types ◽

Cell Transcriptome ◽

B Cell Subsets ◽

Single Cell Transcriptome

Teleost fish anterior kidney (AK) is an important hematopoietic organ with multifarious immune cells, which have immune functions comparable to mammalian bone marrow. Myeloid and lymphoid cells locate in the AK, but the lack of useful specific gene markers and antibody-based reagents for the cell subsets makes the identification of the different cell types difficult. Single-cell transcriptome sequencing enables single-cell capture and individual library construction, making the study on the immune cell heterogeneity of teleost fish AK possible. In this study, we examined the transcriptional patterns of 11,388 AK leukocytes using 10× Genomics single-cell RNA sequencing (scRNA-seq). A total of 22 clusters corresponding to five distinct immune cell subsets were identified, which included B cells, T cells, granulocytes, macrophages, and dendritic cells (DCs). However, the subsets of myeloid cells (granulocytes, macrophages, and DCs) were not identified in more detail according to the known specific markers, even though significant differences existed among the clusters. Thereafter, we highlighted the B-cell subsets and identified them as pro/pre B cells, immature/mature B cells, activated B/plasmablasts, or plasma cells based on the different expressions of the transcription factors (TFs) and cytokines. Clustering of the differentially modulated genes by pseudo-temporal trajectory analysis of the B-cell subsets showed the distinct kinetics of the responses of TFs to cell conversion. Moreover, we classified the T cells and discovered that CD3+CD4−CD8−, CD3+CD4+CD8+, CD4+CD8−, and CD4−CD8+ T cells existed in AK, but neither CD4+CD8− nor CD4−CD8+ T cells can be further classified into subsets based on the known TFs and cytokines. Pseudotemporal analysis demonstrated that CD4+CD8− and CD4−CD8+ T cells belonged to different states with various TFs that might control their differentiation. The data obtained above provide a valuable and detailed resource for uncovering the leukocyte subsets in Nile tilapia AK, as well as more potential markers for identifying the myeloid and lymphoid cell types.

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Chronic Myeloid Leukemia Patients on Tyrosine Kinase Inhibitor Have Normal T Cell Responses to Vaccination but An Impaired IgM Humoral Response Associated with Loss of Discrete Memory B Cell Subsets,

Blood ◽

10.1182/blood.v118.21.3753.3753 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3753-3753

Author(s):

Hugues de Lavallade ◽

David Marin ◽

Melanie Hart ◽

Takuya Sekine ◽

Ian Gabriel ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

T Cell Responses ◽

Healthy Controls ◽

Memory B Cell ◽

Cell Responses ◽

B Cell Subsets

Abstract Abstract 3753 The tyrosine kinase inhibitors (TKIs) imatinib (IM), nilotinib (NIL) and dasatinib (DAS) are remarkably effective as single-agent therapy for chronic myeloid leukemia (CML) in chronic phase (CP). However little is known of their potential impact on the immune response. No human in vivo studies to assess how these molecular-targeted drugs affect immune function in patients are available and data from in vitro and animal studies with imatinib have been contradictory, ranging from impaired antigen-specific T-cell response to enhanced stimulation of tolerant T cells. Furthermore, although the immunomodulatory effects of TKIs on T cells, NK cells and dendritic cells have been explored in vitro, little is known of their potential impact on B cells. To characterize the in vivo immunomodulatory effects of TKIs, 51 patients with CP-CML in complete cytogenetic response (CCyR) on standard dose IM (n=26), DAS (n=14) or NIL (n=12) and 28 adult controls were recruited during two influenza seasons (2008 and 2009). Patients and controls were concomitantly immunized with an influenza vaccine (Ph. Eur. 2008/2009 or Ph. Eur. 2009/2010, CSL Biotherapies) and with the 23-valent polysaccharide pneumococcal vaccine (Pneumovax II; Sanofi Pasteur MSD). Peripheral blood mononuclear cells (PBMCs) and serum samples were collected from patients and donors prior to vaccination and T and B responses to vaccination were assessed at 4 weeks and at 2–3 months post-immunization. T-cell responses to influenza vaccine were analyzed quantitatively and qualitatively using flow cytometry and intracellular cytokine assay for TNF-α, IFN-γ, IL-2 and the cytotoxicity marker CD107a. Serum titers of IgM and IgG pneumococcal antibodies were determined by ELISA. Analysis of B cell subsets was performed using flow cytometry and correlated with the pneumococcal IgM and IgG humoral response. Following vaccination, Flu-specific T cells were detected in 24/51 (47.0%) patients on TKI and 15/24 (62.5%) healthy controls (p=0.16). Polyfunctional T-cell responses (defined as the production of 2 or more cytokines or one cytokine and the cytotoxic marker CD107a) were induced in 6/10 evaluable patients and 4/8 normal controls (p=1.0). T-cell independent humoral responses to vaccination were assessed in 45 patients and 12 healthy controls by measuring pneumococcal IgM titers. Four weeks postimmunization, 11/12 (92%) controls achieved IgM pneumococcal Ab titers >80 U/ml compared to only 23/45 (53%) CML patients on TKI (p=0.010). The pneumococcal IgM titers were significantly lower in patients with CML on TKI compared to healthy controls (median, 89.0 U/ml, range 5–200 vs 200 U/ml, range 58–200, p=0.0006), suggesting that CML patients on TKI have impaired IgM responses to vaccination. To further characterize the humoral immune response to Pneumovax, we stratified CML patients based on their pneumococcal IgM titers. We found a significantly lower percentage of IgM memory B cell subset in CML patients who failed to mount a significant pneumococcal IgM response compared to patients who achieved a pneumococcal IgM response (median, 6.25% vs 16.4%, p=0.0059) and healthy controls (median, 6.25% vs 14.3%, p=0.0086). Furthermore, we found a significant correlation between anti-pneumococcal IgM titers and IgM memory B cell percentage (Spearman rank correlation test, r=0.61, p<.0001). To investigate a putative role of TKIs for the loss of IgM memory B cell subsets in CML patients, we determined the frequencies of IgM memory B cells in paired samples collected from 15 CML-CP patients at diagnosis (i.e. prior to initiating IM) and once CCyR was achieved. We found a significant decrease in the percentage of IgM memory B cells in CML-CP patients treated with IM compared to the pre-treatment sample (median 9.4%, vs. 15.2% respectively, p=0.0023). In summary, patients with CML on TKIs can mount effective T-cell immune responses to influenza vaccination. Our data suggest that TKIs (IM, DAS and NIL) impair T-cell independent humoral immune responses, namely IgM responses to vaccination. This is associated with a loss of IgM memory B cell subsets. Further investigations to understand the mechanisms by which TKIs may impact B-cell subsets are underway. These results are of particular interest in terms of the long-term effects of TKI on tumor immune surveillance and susceptibility to infections and may have implication for vaccination strategies in CML patients. Disclosures: No relevant conflicts of interest to declare.

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Reprogramming Aberrant B Cell-Subsets to Improve Immune Function in Multiple Myeloma

Blood ◽

10.1182/blood.v120.21.3986.3986 ◽

2012 ◽

Vol 120 (21) ◽

pp. 3986-3986

Author(s):

Rao H. Prabhala ◽

Andreea Negroiu ◽

Saem Lee ◽

Mariateresa Fulciniti ◽

Puru Nanjappa ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Board Of Directors ◽

Peripheral Blood ◽

Advisory Committees ◽

Healthy Donors ◽

Ifn Γ ◽

B Cell Subsets

Abstract Abstract 3986 B cell-malignancies exhibit considerable immune dysfunction particularly in multiple myeloma (MM). We have previously demonstrated that in T cell-compartment, regulatory T helper cells are dysfunctional in multiple myeloma (MM) while Th17 cells are significantly elevated and IL-17 produced by them is associated with MM cell growth and survival as well as suppressed immune responses and bone disease. We have here investigated the B cell-subsets and their ability to re-program anti-tumor immunity in MM. We have first characterised four different B cell-subsets (B1a, B1b, B2 and regulatory B cells) using 10-color flow cytometric analysis in both peripheral blood and bone-marrow (BM) samples from MM patients compared with normal healthy donors. We observe that CD5+ B1a-B cells are significantly elevated in peripheral blood of MM patients (N=7) compared to healthy donor (N=15) (42±8% vs 13±3%, respectively, p<0.05); while normal B cells (B2 cells) are significantly reduced in peripheral blood (29.8±6.5, p<0.05) and in the BM samples (11±4.8, N=4, p<0.05) of MM patients compared to healthy donors (59±3, and 60.2±2, N=10, respectively). We also observed that both B1b (47.9±18 vs. 22.8±4) and regulatory B cells (7.1±4.5 vs. 1.54±0.3) are elevated in BM samples of MM compared to healthy donors, however there were no differences in B1b and regulatory B cells in the peripheral blood of MM compared to healthy donor samples. Interestingly, in myeloma we observe higher levels of activated B cell subsets but lower levels of memory B cell subsets compared to healthy donors. These results, particularly very low levels of normal B cells in MM patients, may explain the decreased levels of uninvolved immunoglobulin in MM. As removal of B cell population has been shown to re-program T helper cell populations, we next investigated impact of B cell population on T cell activation. We activated normal PBMC via the anti-CD3 antibody, in the presence or absence of B or CD25+ cells and measured intra-cellular IFN-γ levels in CD69+ cells. We found that the absence of B cells significantly inhibited interferon-producing T cells compared to PBMC (by 43%; p<0.05). Importantly, following removal of CD25+ cells, which consists of both Tregs and activated memory T cells, with or without B cells, we did not observe any difference in the inhibition of IFN-γ, indicating that B cells are influencing memory T cells rather than naïve T cells for the production of IFN-γ. This prompted us to identify the phenotypic signature of regulatory T cell populations when purified memory T cells are polarized with the regulatory T cell cocktail in presence or absence of B cells. We observed that B cells reduce FOXP3 expression by 18 %(N=5) and establish cognitive interactions with T cells. This occurred by increasing the expression of GITR (154%) and CTLA4 (54%); while reducing PD1 (−24%) and OX40 (−21%) expression on T cells without affecting HLA expression. We have also observed these improvements by B cell modulation on T cells in MM. Our results indicate that targeting these re-programmable capabilities of B cells to modulate T helper cell populations may enable us to improve T cell function in MM; and may improve immune function in MM and also allow us to enhance responses to vaccinations. Disclosures: Ghobrial: Millennium: Advisory Board Other; Novartis: Advisory Board, Advisory Board Other. Richardson:Novartis: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees; Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees. Treon:Onyx: Research Funding; Celgene: Research Funding; Pharmacyclics: Research Funding; Cephalon: Consultancy; Avila: Consultancy. Anderson:Celgene, Millennium, BMS, Onyx: Membership on an entity's Board of Directors or advisory committees; Acetylon, Oncopep: Scientific Founder, Scientific Founder Other.

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B cell depletion impairs vaccination-induced CD8+ T cell responses in a type I interferon-dependent manner

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-220435 ◽

2021 ◽

pp. annrheumdis-2021-220435

Author(s):

Theresa Graalmann ◽

Katharina Borst ◽

Himanshu Manchanda ◽

Lea Vaas ◽

Matthias Bruhn ◽

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Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Cell Expansion ◽

De Novo ◽

T Cell Responses ◽

Type I ◽

Cell Responses ◽

T Cell Expansion

ObjectivesThe monoclonal anti-CD20 antibody rituximab is frequently applied in the treatment of lymphoma as well as autoimmune diseases and confers efficient depletion of recirculating B cells. Correspondingly, B cell-depleted patients barely mount de novo antibody responses during infections or vaccinations. Therefore, efficient immune responses of B cell-depleted patients largely depend on protective T cell responses.MethodsCD8+ T cell expansion was studied in rituximab-treated rheumatoid arthritis (RA) patients and B cell-deficient mice on vaccination/infection with different vaccines/pathogens.ResultsRituximab-treated RA patients vaccinated with Influvac showed reduced expansion of influenza-specific CD8+ T cells when compared with healthy controls. Moreover, B cell-deficient JHT mice infected with mouse-adapted Influenza or modified vaccinia virus Ankara showed less vigorous expansion of virus-specific CD8+ T cells than wild type mice. Of note, JHT mice do not have an intrinsic impairment of CD8+ T cell expansion, since infection with vaccinia virus induced similar T cell expansion in JHT and wild type mice. Direct type I interferon receptor signalling of B cells was necessary to induce several chemokines in B cells and to support T cell help by enhancing the expression of MHC-I.ConclusionsDepending on the stimulus, B cells can modulate CD8+ T cell responses. Thus, B cell depletion causes a deficiency of de novo antibody responses and affects the efficacy of cellular response including cytotoxic T cells. The choice of the appropriate vaccine to vaccinate B cell-depleted patients has to be re-evaluated in order to efficiently induce protective CD8+ T cell responses.

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