scholarly journals CD200R1 and CD200R1L expression is regulated during B cell development in swine and modulates the Ig production in response to the TLR7 ligand imiquimoid

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251187
Author(s):  
Teresa Poderoso ◽  
Paloma Martínez De la Riva ◽  
Belén Álvarez ◽  
Ángel Ezquerra ◽  
Javier Domínguez ◽  
...  

The CD200R family comprises a group of paired receptors that can modulate the activation of immune cells. They are expressed both on myeloid cells and lymphocyte subsets. Here we report that the expression of these receptors on porcine B cells is tightly regulated, being mainly expressed on mature cells. The expression of the inhibitory receptors CD200R1 and/or its splicing variant CD200R1X2, either in combination or not with the activating receptor CD200R1L, is upregulated in sIgM+ effector/memory cells, and tends to decline thereafter as these cells progress to plasmablasts or switch the Ig isotype. sIgM+ naïve and primed cells only express, by contrast, the CD200R1X2 receptor. B-1 like cells also express CD200R1 isoforms, either alone or in combination with CD200R1L. Treatment of peripheral blood mononuclear cells with a monoclonal antibody specific for inhibitory receptors, enhances the IgM and IgG production induced by TLR7 stimulation suggesting a modulatory role of B cell functions of these receptors.

2019 ◽  
Author(s):  
Eladio J. Márquez ◽  
Cheng-han Chung ◽  
Radu Marches ◽  
Robert J. Rossi ◽  
Djamel Nehar-Belaid ◽  
...  

AbstractDifferences in immune function and responses contribute to health- and life-span disparities between sexes. However, the role of sex in immune system aging is not well understood. Here, we characterize peripheral blood mononuclear cells from 172 healthy adults 22-93 years of age using ATAC-seq, RNA-seq, and flow-cytometry. These data reveal a shared epigenomic signature of aging including declining naïve T cell and increasing monocyte/cytotoxic cell functions. These changes were greater in magnitude in men and accompanied by a male-specific genomic decline in B-cell specific loci. Age-related epigenomic changes first spike around late-thirties with similar timing and magnitude between sexes, whereas the second spike is earlier and stronger in men. Unexpectedly, genomic differences between sexes increase after age 65, with men having higher innate and pro-inflammatory activity and lower adaptive activity. Impact of age and sex on immune cell genomes can be visualized at https://immune-aging.jax.org to provide insights into future studies.


2021 ◽  
Vol 23 (4) ◽  
pp. 969-974
Author(s):  
A. V. Kolerova ◽  
D. A. Mikailova ◽  
M. A. Beimanova ◽  
E. A. Blinova

Psoriasis is a chronic autoimmune disease in which the skin and joints are involved in the pathological process. It was found that the recurrence of rashes in this disease occurs due to the resident memory cells of the skin. The number of CD4+CCR3+ effector memory cells in peripheral blood correlates with the severity of the disease. Therefore, the aim of our work is to study the phenotype of peripheral blood memory cells in patients with psoriasis.The study included 6 healthy donors: average age – 45.4 (min – 29, max – 55), women – 3, men – 3; 10 patients with psoriasis: women – 4, men – 6, average age – 37.3 (min – 23, max – 57), of which 5 patients with PASI > 10 and 5 patients with PASI < 10. The exclusion criteria for the study were the presence of autoimmune, oncological and hematological diseases, systemic therapy with immunosuppressive drugs for 1 month. Patients signed informed consent to participate in the study. Isolation of peripheral blood mononuclear cells was performed in a density gradient of ficoll-urographin (p = 1.082 g/L). Then cells were stained with fluorochrome-conjugated monoclonal antibodies to surface markers of central (Tcm) and effector (Tem) CD4+ memory cells (CD4, CD45RO, CD197), the α-chain of the IL-7 receptor (CD127), and the γ-chain of the IL-7 receptor (CD132). Statistical analysis of the data obtained was performed using the Statistica 6.0 software package.The percent of Tcm in the peripheral blood of donors was 33.4% (in – 18.2, max – 43.7), Tem – 28.7% (min – 13.6, max – 38.9), in patients with psoriasis: Tcm – 28.65% (min – 13.3, max – 59.6), Tem – 21.5% (min – 9.3, max – 38.6). In the peripheral blood of patients with psoriasis, among the central CD4+ memory cells, the proportion of CD127+CD132- -cells is 26.00%, CD127+CD132+ – 1.69%, CD127+CD132- – 69.00%, CD127- CD132+ – 1.94%. Among effector CD4+ memory cells, the proportion of CD127+CD132- -cells is 23.58%, CD127+CD132+ – 1.18%, CD127+CD132- – 69.84%, CD127- CD132+ – 0.70%. A direct correlation was found between the number of CD127- CD132+ central memory cells and the PASI value (r = 0.639, p < 0.05).In patients with psoriasis, the proportion of central memory cells is higher than in healthy donors, while the number of effector memory cells is lower. A direct correlation was found between the number of central cells expressing the γ-chain of the IL-7 receptor and the severity of the disease. Activated memory cells are characterized by high expression of CD132. It can be assumed that this population of memory cells plays a role in maintaining autoimmune inflammation in patients with this disease, and also participates in the repopulation of skin resident memory cells. 


Gut ◽  
2020 ◽  
pp. gutjnl-2020-321731
Author(s):  
Dominik Aschenbrenner ◽  
Maria Quaranta ◽  
Soumya Banerjee ◽  
Nicholas Ilott ◽  
Joanneke Jansen ◽  
...  

ObjectiveDysregulated immune responses are the cause of IBDs. Studies in mice and humans suggest a central role of interleukin (IL)-23-producing mononuclear phagocytes in disease pathogenesis. Mechanistic insights into the regulation of IL-23 are prerequisite for selective IL-23 targeting therapies as part of personalised medicine.DesignWe performed transcriptomic analysis to investigate IL-23 expression in human mononuclear phagocytes and peripheral blood mononuclear cells. We investigated the regulation of IL-23 expression and used single-cell RNA sequencing to derive a transcriptomic signature of hyperinflammatory monocytes. Using gene network correlation analysis, we deconvolved this signature into components associated with homeostasis and inflammation in patient biopsy samples.ResultsWe characterised monocyte subsets of healthy individuals and patients with IBD that express IL-23. We identified autosensing and paracrine sensing of IL-1α/IL-1β and IL-10 as key cytokines that control IL-23-producing monocytes. Whereas Mendelian genetic defects in IL-10 receptor signalling induced IL-23 secretion after lipopolysaccharide stimulation, whole bacteria exposure induced IL-23 production in controls via acquired IL-10 signalling resistance. We found a transcriptional signature of IL-23-producing inflammatory monocytes that predicted both disease and resistance to antitumour necrosis factor (TNF) therapy and differentiated that from an IL-23-associated lymphocyte differentiation signature that was present in homeostasis and in disease.ConclusionOur work identifies IL-10 and IL-1 as critical regulators of monocyte IL-23 production. We differentiate homeostatic IL-23 production from hyperinflammation-associated IL-23 production in patients with severe ulcerating active Crohn’s disease and anti-TNF treatment non-responsiveness. Altogether, we identify subgroups of patients with IBD that might benefit from IL-23p19 and/or IL-1α/IL-1β-targeting therapies upstream of IL-23.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nirupama D. Verma ◽  
Andrew D. Lam ◽  
Christopher Chiu ◽  
Giang T. Tran ◽  
Bruce M. Hall ◽  
...  

AbstractResting and activated subpopulations of CD4+CD25+CD127loT regulatory cells (Treg) and CD4+CD25+CD127+ effector T cells in MS patients and in healthy individuals were compared. Peripheral blood mononuclear cells isolated using Ficoll Hypaque were stained with monoclonal antibodies and analysed by flow cytometer. CD45RA and Foxp3 expression within CD4+ cells and in CD4+CD25+CD127loT cells identified Population I; CD45RA+Foxp3+, Population II; CD45RA−Foxp3hi and Population III; CD45RA−Foxp3+ cells. Effector CD4+CD127+ T cells were subdivided into Population IV; memory /effector CD45RA− CD25−Foxp3− and Population V; effector naïve CD45RA+CD25−Foxp3−CCR7+ and terminally differentiated RA+ (TEMRA) effector memory cells. Chemokine receptor staining identified CXCR3+Th1-like Treg, CCR6+Th17-like Treg and CCR7+ resting Treg. Resting Treg (Population I) were reduced in MS patients, both in untreated and treated MS compared to healthy donors. Activated/memory Treg (Population II) were significantly increased in MS patients compared to healthy donors. Activated effector CD4+ (Population IV) were increased and the naïve/ TEMRA CD4+ (Population V) were decreased in MS compared to HD. Expression of CCR7 was mainly in Population I, whereas expression of CCR6 and CXCR3 was greatest in Populations II and intermediate in Population III. In MS, CCR6+Treg were lower in Population III. This study found MS is associated with significant shifts in CD4+T cells subpopulations. MS patients had lower resting CD4+CD25+CD45RA+CCR7+ Treg than healthy donors while activated CD4+CD25hiCD45RA−Foxp3hiTreg were increased in MS patients even before treatment. Some MS patients had reduced CCR6+Th17-like Treg, which may contribute to the activity of MS.


2021 ◽  
Author(s):  
Emily Stephenson ◽  
◽  
Gary Reynolds ◽  
Rachel A. Botting ◽  
Fernando J. Calero-Nieto ◽  
...  

AbstractAnalysis of human blood immune cells provides insights into the coordinated response to viral infections such as severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). We performed single-cell transcriptome, surface proteome and T and B lymphocyte antigen receptor analyses of over 780,000 peripheral blood mononuclear cells from a cross-sectional cohort of 130 patients with varying severities of COVID-19. We identified expansion of nonclassical monocytes expressing complement transcripts (CD16+C1QA/B/C+) that sequester platelets and were predicted to replenish the alveolar macrophage pool in COVID-19. Early, uncommitted CD34+ hematopoietic stem/progenitor cells were primed toward megakaryopoiesis, accompanied by expanded megakaryocyte-committed progenitors and increased platelet activation. Clonally expanded CD8+ T cells and an increased ratio of CD8+ effector T cells to effector memory T cells characterized severe disease, while circulating follicular helper T cells accompanied mild disease. We observed a relative loss of IgA2 in symptomatic disease despite an overall expansion of plasmablasts and plasma cells. Our study highlights the coordinated immune response that contributes to COVID-19 pathogenesis and reveals discrete cellular components that can be targeted for therapy.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 112.2-113
Author(s):  
M. Gatto ◽  
S. Bjursten ◽  
C. Jonell ◽  
C. Jonsson ◽  
S. Mcgrath ◽  
...  

Background:Inflammatory arthritis (IA) is frequent among rheumatic side effects induced by checkpoint inhibitor (CPI) therapy for metastatic malignancies1. While T cells are likely to sustain the inflammatory process2, fewer data are available concerning the role of B cells3.Objectives:To investigate the phenotype of circulating B cells in patients who develop CPI-induced IA (CPI-IA) and to compare it with features of B cells in patients not developing immune-related adverse events (irAE) upon CPI treatment.Methods:B cell subsets at baseline (before CPI initiation) and during CPI treatment were analyzed in CPI-IA patients and in patients receiving CPI but who did not develop irAE (non-irAE). Peripheral blood mononuclear cells (PBMC) were analyzed by flow cytometry and B cells were identified as CD19+ and divided into naïve (CD27-IgD+), memory (CD27+IgD+/-), double negative (CD27-IgD-) and transitional (CD10+CD24+CD38+/hi) B cells. Levels of CD21, an activation marker on transitional B cells, were also analyzed. Non-parametric tests were used for analysis of differences between groups.Results:Six CPI-IA and 7 non-irAE patients matched for age, gender and CPI treatment were included, who had received CPI treatment due to metastatic melanoma. Flow cytometry revealed a significant increase of circulating B cells (p=0.002) (Figure 1A) and especially of transitional B cells in CPI-IA patients vs. non-irAE (median %, range: 7.8 (4.5-11.4) vs. 3.2 (1.6-4.3),p=0.007) (Figure 1B), while no remarkable changes were seen across other subsets. Transitional B cell levels significantly decreased from active to quiescent CPI-IA in all patients (p=0.008). In two CPI-IA patients for whom baseline sampling was available, the increase of transitional levels occurred early after CPI treatment and before CPI-IA onset. Levels of expression of CD21 on transitional B cells were increased in CPI-IA vs. non-irAE (p=0.01).Conclusion:Transitional B cells are expanded in CPI-IA patients and seem to increase early after start of CPI therapy. Monitoring this B cell subset might lead to closer follow-up and earlier diagnosis of CPI-IA.References:[1]Ramos-Casals M, Brahmer JR, Callahan MK, et al. Immune-related adverse events of checkpoint inhibitors. Nat Rev Dis Primers 2020;6:38[2]Murray-Brown W, Wilsdon TD, Weedon H, et al. Nivolumab-induced synovitis is characterized by florid T cell infiltration and rapid resolution with synovial biopsy-guided therapy. J Immunother Cancer 2020;8:e000281[3]Das R, Bar N, Ferreira M, et al. Early B cell changes predict autoimmunity following combination immune checkpoint blockade. J Clin Invest. 2018;128:715-2Disclosure of Interests:None declared


Author(s):  
Véronique Avettand-Fenoel ◽  
Jérôme Lechenadec ◽  
Mariama Sadjo Diallo ◽  
Marine Fillion ◽  
Adeline Melard ◽  
...  

Abstract Background Early combined antiretroviral therapy (cART) limits the total HIV-DNA load in children. However, data on its impact in older children and adolescents remain scarce. This study aims to compare HIV reservoirs in children (5-12 years) and adolescents (13-17 years) who started cART before 6 months (early (E-)group) or after 2 years old (late (L-)group). Methods The ANRS-EP59-CLEAC study prospectively enrolled 76 HIV-1 perinatally-infected patients who reached HIV-RNA&lt;400 copies/mL less than 24 months after cART initiation, regardless of subsequent viral suppression (E-group: 27 children, 9 adolescents; L-group: 19 children, 21 adolescents). Total and integrated HIV-DNA were quantified in blood and in CD4+ T cell subsets. A substudy assessed HIV reservoir inducibility after ex vivo peripheral blood mononuclear cells (PBMCs) stimulation. Results Total HIV-DNA levels were lower in early- than late-treated patients (Children: 2.14 vs 2.87 log cp/million PBMCs, p&lt;0.0001; Adolescents: 2.25 vs 2.74log, p&lt;0.0001). Low reservoir was independently associated with treatment precocity, protective HLA and low cumulative viremia since cART initiation. The 60 participants with undetectable integrated HIV-DNA started cART earlier than the other patients (4 vs 54 months, p=0.03). In those with sustained virological control, transitional memory and effector memory CD4+T cells were less infected in the E-group than in the L-group (p=0.03 and 0.02, respectively). Viral inducibility of reservoir cells after normalization to HIV-DNA levels was similar between the groups. Conclusions Early cART results in a smaller blood HIV reservoir until adolescence, but all tested participants had an inducible reservoir. This deserves cautious consideration for HIV remission strategies.


Blood ◽  
2008 ◽  
Vol 112 (3) ◽  
pp. 770-781 ◽  
Author(s):  
Mithun Vinod Shah ◽  
Ranran Zhang ◽  
Rosalyn Irby ◽  
Ravi Kothapalli ◽  
Xin Liu ◽  
...  

Abstract T-cell large granular lymphocyte (LGL) leukemia is characterized by clonal expansion of CD3+CD8+ cells. Leukemic LGLs correspond to terminally differentiated effector-memory cytotoxic T lymphocytes (CTLs) that escape Fas-mediated activation-induced cell death (AICD) in vivo. The gene expression signature of peripheral blood mononuclear cells from 30 LGL leukemia patients showed profound dysregulation of expression of apoptotic genes and suggested uncoupling of activation and apoptotic pathways as a mechanism for failure of AICD in leukemic LGLs. Pathway-based microarray analysis indicated that balance of proapoptotic and antiapoptotic sphingolipid-mediated signaling was deregulated in leukemic LGLs. We further investigated sphingolipid pathways and found that acid ceramidase was constitutively overexpressed in leukemic LGLs and that its inhibition induced apoptosis of leukemic LGLs. We also showed that S1P5 is the predominant S1P receptor in leukemic LGLs, whereas S1P1 is down-regulated. FTY720, a functional antagonist of S1P-mediated signaling, induced apoptosis in leukemic LGLs and also sensitized leukemic LGLs to Fas-mediated death. Collectively, these results show a role for sphingolipid-mediated signaling as a mechanism for long-term survival of CTLs. Therapeutic targeting of this pathway, such as use of FTY720, may have efficacy in LGL leukemia.


1993 ◽  
Vol 178 (4) ◽  
pp. 1347-1355 ◽  
Author(s):  
M E Surette ◽  
R Palmantier ◽  
J Gosselin ◽  
P Borgeat

Stimulation of heparinized blood with 1 microM formyl-methionyl-leucyl-phenylalanine (FMLP) resulted in the formation of &lt; 30 pmol/ml plasma of 5-lipoxygenase (5-LO) products. The preincubation of blood with 1 microgram/ml of lipopolysaccharide (LPS) (Escherichia coli 0111-B4) for 30 min before stimulation with FMLP resulted in the accumulation of 250-300 pmol of 5-LO products per ml plasma. The major products detected were leukotriene B4 and (5S)-hydroxy-6,8,11,14-eicosatetraenoic acid which were produced in equivalent amounts. The priming activity was detectable with as little as 1-10 ng LPS per ml blood and was optimal using 1-10 micrograms LPS/ml blood. The priming for 5-LO product synthesis was optimal after 20-30 min of preincubation with LPS and declined at preincubation times &gt; 30 min. The priming effect of LPS was also observed using the complement fragment C5a or interleukin 8 as agonists. Polymorphonuclear leukocytes (PMN) and peripheral blood mononuclear cells accounted for 80 and 20% of the synthesis of 5-LO products, respectively. The ability of LPS to prime isolated PMN was dependent on the presence of plasma and was inhibited by the anti-CD14 antibody IOM2, indicating a CD14-dependent priming mechanism. The priming of whole blood with tumor necrosis factor alpha (TNF-alpha) and LPS was additive and the presence of mononuclear cells did not enhance the ability of LPS to prime PMN, indicating that the priming activity of LPS is independent of LPS-induced TNF-alpha synthesis. The mechanism by which LPS enhance 5-LO product synthesis in PMN was investigated. Treatment of PMN with LPS strongly enhanced the release of arachidonic acid after stimulation with FMLP. The release of arachidonic acid was optimal 2-3 min after stimulation with FMLP, attaining levels 5-15-fold greater than those observed in unprimed cells stimulated with FMLP. These results demonstrate that LPS dramatically increases the ability of blood to generate 5-LO products, and support the putative role of leukotrienes in pathological states involving LPS.


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