A novel MyD-1 (SIRP-1α) signaling pathway that inhibits LPS-induced TNFα production by monocytes

Blood ◽  
2003 ◽  
Vol 102 (7) ◽  
pp. 2532-2540 ◽  
Author(s):  
Rosemary E. Smith ◽  
Vanshree Patel ◽  
Sandra D. Seatter ◽  
Maureen R. Deehan ◽  
Marion H. Brown ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Kinase Inhibitor ◽  
Tyrosine Phosphatase ◽  
Peripheral Blood Mononuclear ◽  
Necrosis Factor Alpha ◽  
Purified Protein Derivative ◽  
Sequential Activation ◽  
Novel Target

Abstract MyD-1 (CD172) is a member of the family of signal regulatory phosphatase (SIRP) binding proteins, which is expressed on human CD14+ monocytes and dendritic cells. We now show a novel role for MyD-1 in the regulation of the innate immune system by pathogen products such as lipopolysaccharide (LPS), purified protein derivative (PPD), and Zymosan. Specifically, we demonstrate that ligation of MyD-1 on peripheral blood mononuclear cells (PBMCs) inhibits tumor necrosis factor alpha (TNFα) secretion but has no effect on other cytokines induced in response to each of these products. In an attempt to understand the molecular mechanisms underlying this surprisingly selective effect we investigated signal transduction pathways coupled to MyD-1. Ligation of the SIRP was found to recruit the tyrosine phosphatase SHP-2 and promote sequential activation of phosphatidylinositol (PI) 3-kinase, phospholipase D, and sphingosine kinase. Inhibition of LPS-induced TNFα secretion by MyD-1 appears to be mediated by this pathway, as the PI 3-kinase inhibitor wortmannin restores normal LPS-driven TNFα secretion. MyD-1-coupling to this PI 3-kinase-dependent signaling pathway may therefore present a novel target for the development of therapeutic strategies for combating TNFα production and consequent inflammatory disease. (Blood. 2003;102:2532-2540)

scholarly journals Downregulation of CD45 Signaling in COVID-19 Patients Is Reversed by C24D, a Novel CD45 Targeting Peptide

2021 ◽  
Vol 8 ◽  
Author(s):  
Danny Alon ◽  
Yossi Paitan ◽  
Eyal Robinson ◽  
Nirit Ganor ◽  
Julia Lipovetsky ◽  
...  
Keyword(s):  
Immune System ◽  
Signaling Pathway ◽  
Intracellular Signaling ◽  
Mononuclear Cells ◽  
Tyrosine Phosphatase ◽  
Cell Receptor ◽  
Peripheral Blood Mononuclear ◽  
Intracellular Signals ◽  
Number Of Patients ◽  
Targeting Peptide

CD45, the predominant transmembrane tyrosine phosphatase in leukocytes, is required for the efficient induction of T cell receptor signaling and activation. We recently reported that the CD45-intracellular signals in peripheral blood mononuclear cells (PBMCs) of triple negative breast cancer (TNBC) patients are inhibited. We also reported that C24D, an immune modulating therapeutic peptide, binds to CD45 on immune-suppressed cells and resets the functionality of the immune system via the CD45 signaling pathway. Various studies have demonstrated that also viruses can interfere with the functions of CD45 and that patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are immune-suppressed. Given the similarity between the role of CD45 in viral immune suppression and our findings on TNBC, we hypothesized that the C24D peptide may have a similar “immune-resetting” effect on PBMCs from COVID-19 patients as it did on PBMCs from TNBC patients. We tested this hypothesis by comparing the CD45/TCR intracellular signaling in PBMCs from ten COVID-19 patients vs. PBMCs from ten healthy volunteers. Herein, we report our findings, demonstrating the immune reactivating effect of C24D via the phosphorylation of the tyrosine 505 and 394 in Lck, the tyrosine 493 in ZAP-70 and the tyrosine 172 in VAV-1 proteins in the CD45 signaling pathway. Despite the relatively small number of patients in this report, the results demonstrate that C24D rescued CD45 signaling. Given the central role played by CD45 in the immune system, we suggest CD45 as a potential therapeutic target.

scholarly journals Inhibition of SHP2 ameliorates psoriasis by decreasing TLR7 endosome localization

2020 ◽  
Author(s):  
Yuyu Zhu ◽  
Fenli Shao ◽  
Wei Yan ◽  
Qiang Xu ◽  
Yang Sun
Keyword(s):  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Tyrosine Phosphatase ◽  
Skin Inflammation ◽  
Peripheral Blood Mononuclear ◽  
Genetic Ablation ◽  
Src Homology 2 ◽  
Promising Therapeutic Approach ◽  
Src Homology ◽  
Src Homology 2 Domain

Psoriasis is a complex chronic inflammatory skin disease with unclear molecular mechanisms. Here, we identify Src homology-2 domain containing protein tyrosine phosphatase-2 (SHP2) as a novel accelerator of psoriasis development. Both genetic ablation of SHP2 in macrophages and pharmacological inhibition of SHP2 prevents the development of psoriasis-like skin inflammation in an imiquimod-induced murine model of psoriasis. Mechanistically, SHP2 promotes the trafficking of Toll-like receptor 7 (TLR7) from Golgi to endosome through its interaction with and dephosphorylation of TLR7 at Tyr1024, which promotes the ubiquitination of TLR7 and psoriasis-like skin inflammation. Importantly, SHP2 allosteric inhibitor SHP099 reduces the expression of pro-inflammatory cytokines in peripheral blood mononuclear cells from human patients with psoriasis. Collectively, our findings identify SHP2 as a novel regulator of psoriasis and suggest that SHP2 inhibition may be a promising therapeutic approach for psoriatic patients.

scholarly journals Sirt1 Activity in PBMCs as a Biomarker of Different Heart Failure Phenotypes

Biomolecules ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1590
Author(s):  
Valeria Conti ◽  
Graziamaria Corbi ◽  
Maria Vincenza Polito ◽  
Michele Ciccarelli ◽  
Valentina Manzo ◽  
...  
Keyword(s):  
Heart Failure ◽  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Statistical Significance ◽  
University Hospital ◽  
Peripheral Blood Mononuclear ◽  
Necrosis Factor Alpha ◽  
Angiotensin Converting Enzyme 2 ◽  
Tnf Α ◽  
The University

Heart Failure (HF) is a syndrome, which implies the existence of different phenotypes. The new categorization includes patients with preserved ejection fraction (HFpEF), mid-range EF (HFmrEF), and reduced EF (HFrEF) but the molecular mechanisms involved in these HF phenotypes have not yet been exhaustively investigated. Sirt1 plays a crucial role in biological processes strongly related to HF. This study aimed to evaluate whether Sirt1 activity was correlated with EF and other parameters in HFpEF, HFmrEF, and HFrEF. Seventy patients, HFpEF (n = 23), HFmrEF (n = 23) and HFrEF (n = 24), were enrolled at the Cardiology Unit of the University Hospital of Salerno. Sirt1 activity was measured in peripheral blood mononuclear cells (PBMCs). Angiotensin-Converting Enzyme 2 (ACE2) activity, Tumor Necrosis Factor-alpha (TNF-α) and Brain Natriuretic Peptide (BNP) levels were quantified in plasma. HFpEF showed lower Sirt1 and ACE2 activities than both HFmrEF and HFrEF (p < 0.0001), without difference compared to No HF controls. In HFmrEF and HFrEF a very strong correlation was found between Sirt1 activity and EF (r2 = 0.899 and r2 = 0.909, respectively), and between ACE2 activity and Sirt1 (r2 = 0.801 and r2 = 0.802, respectively). HFrEF showed the highest TNF-α levels without reaching statistical significance. Significant differences in BNP were found among the groups, with the highest levels in the HFrEF. Determining Sirt1 activity in PBMCs is useful to distinguish the HF patients’ phenotypes from each other, especially HFmrEF/HFrEF from HFpEF.

scholarly journals Lipopolysaccharides prime whole human blood and isolated neutrophils for the increased synthesis of 5-lipoxygenase products by enhancing arachidonic acid availability: involvement of the CD14 antigen.

1993 ◽  
Vol 178 (4) ◽  
pp. 1347-1355 ◽  
Author(s):  
M E Surette ◽  
R Palmantier ◽  
J Gosselin ◽  
P Borgeat
Keyword(s):  
Arachidonic Acid ◽  
Mononuclear Cells ◽  
Leukotriene B4 ◽  
Eicosatetraenoic Acid ◽  
Tnf Alpha ◽  
Peripheral Blood Mononuclear ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Priming Activity

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.

scholarly journals Molecular Cloning, Expression, and Immunogenicity of MTB12, a Novel Low-Molecular-Weight Antigen Secreted byMycobacterium tuberculosis

1998 ◽  
Vol 66 (9) ◽  
pp. 4208-4214 ◽  
Author(s):  
John R. Webb ◽  
Thomas S. Vedvick ◽  
Mark R. Alderson ◽  
Jeffrey A. Guderian ◽  
Shyian S. Jen ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Molecular Cloning ◽  
Mononuclear Cells ◽  
Single Copy ◽  
Low Molecular Weight ◽  
Peripheral Blood Mononuclear ◽  
Purified Protein Derivative ◽  
Culture Filtrate Proteins ◽  
Processed Form

ABSTRACT Proteins secreted into the culture medium by Mycobacterium tuberculosis are thought to play an important role in the development of protective immune responses. In this report, we describe the molecular cloning of a novel, low-molecular-weight antigen (MTB12) secreted by M. tuberculosis. Sequence analysis of the MTB12 gene indicates that the protein is initially synthesized as a 16.6-kDa precursor protein containing a 48-amino-acid hydrophobic leader sequence. The mature, fully processed form of MTB12 protein found in culture filtrates has a molecular mass of 12.5 kDa. MTB12 protein constitutes a major component of the M. tuberculosis culture supernatant and appears to be at least as abundant as several other well-characterized culture filtrate proteins, including members of the 85B complex. MTB12 is encoded by a single-copy gene which is present in both virulent and avirulent strains of the M. tuberculosis complex, the BCG strain of M. bovis, and M. leprae. Recombinant MTB12 containing an N-terminal six-histidine tag was expressed in Escherichia coli and purified by affinity chromatography. Recombinant MTB12 protein elicited in vitro proliferative responses from the peripheral blood mononuclear cells of a number of purified protein derivative-positive (PPD+) human donors but not from PPD− donors.

scholarly journals Molecular mechanisms governing circulating immune cell heterogeneity across different species revealed by single cell sequencing

2021 ◽  
Author(s):  
Zhibin Li ◽  
chengcheng Sun ◽  
Fei Wang ◽  
Xiran Wang ◽  
Jiacheng Zhu ◽  
...  
Keyword(s):  
Single Cell ◽  
Immune Cells ◽  
Evolutionary Biology ◽  
Regulatory Networks ◽  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Immune Cell ◽  
Cell Types ◽  
Genetic Regulatory Networks ◽  
Peripheral Blood Mononuclear

Background: Immune cells play important roles in mediating immune response and host defense against invading pathogens. However, insights into the molecular mechanisms governing circulating immune cell diversity among multiple species are limited. Methods: In this study, we compared the single-cell transcriptomes of 77 957 immune cells from 12 species using single-cell RNA-sequencing (scRNA-seq). Distinct molecular profiles were characterized for different immune cell types, including T cells, B cells, natural killer cells, monocytes, and dendritic cells. Results: The results revealed the heterogeneity and compositions of circulating immune cells among 12 different species. Additionally, we explored the conserved and divergent cellular cross-talks and genetic regulatory networks among vertebrate immune cells. Notably, the ligand and receptor pair VIM-CD44 was highly conserved among the immune cells. Conclusions: This study is the first to provide a comprehensive analysis of the cross-species single-cell atlas for peripheral blood mononuclear cells (PBMCs). This research should advance our understanding of the cellular taxonomy and fundamental functions of PBMCs, with important implications in evolutionary biology, developmental biology, and immune system disorders

scholarly journals A 70-Kilodalton Recombinant Heat Shock Protein ofCandida albicans Is Highly Immunogenic and Enhances Systemic Murine Candidiasis

1998 ◽  
Vol 66 (5) ◽  
pp. 2154-2162 ◽  
Author(s):  
Carla Bromuro ◽  
Roberto La Valle ◽  
Silvia Sandini ◽  
Francesca Urbani ◽  
Clara M. Ausiello ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Mononuclear Cells ◽  
Cell Mediated Immunity ◽  
Healthy Human ◽  
Peripheral Blood Mononuclear ◽  
Necrosis Factor Alpha ◽  
Ifn Γ

ABSTRACT The 70-kDa recombinant Candida albicans heat shock protein (CaHsp70) and its 21-kDa C-terminal and 28-kDa N-terminal fragments (CaHsp70-Cter and CaHsp70-Nter, respectively) were studied for their immunogenicity, including proinflammatory cytokine induction in vitro and in vivo, and protection in a murine model of hematogenous candidiasis. The whole protein and its two fragments were strong inducers of both antibody (Ab; immunoglobulin G1 [IgG1] and IgG2b were the prevalent isotypes) and cell-mediated immunity (CMI) responses in mice. CaHsp70 preparations were also recognized as CMI targets by peripheral blood mononuclear cells of healthy human subjects. Inoculation of CaHsp70 preparations into immunized mice induced rapid production of interleukin-6 (IL-6) and tumor necrosis factor alpha, peaking at 2 to 5 h and declining within 24 h. CaHsp70 and CaHsp70-Cter also induced gamma interferon (IFN-γ), IL-12, and IL-10 but not IL-4 production by CD4+ lymphocytes cocultured with splenic accessory cells from nonimmunized mice. In particular, the production of IFN-γ was equal if not superior to that induced in the same cells by whole, heat-inactivated fungal cells or the mitogenic lectin concanavalin A. In immunized mice, however, IL-4 but not IL-12 was produced in addition to IFN-γ upon in vitro stimulation of CD4+ cells with CaHsp70 and CaHsp70-Cter. These animals showed a decreased median survival time compared to nonimmunized mice, and their mortality was strictly associated with organ invasion by fungal hyphae. Their enhanced susceptibility was attributable to the immunization state, as it did not occur in congenitally athymic nude mice, which were unable to raise either Ab or CMI responses to CaHsp70 preparations. Together, our data demonstrate the elevated immunogenicity of CaHsp70, with which, however, no protection against but rather some enhancement of Candida infection seemed to occur in the mouse model used.

scholarly journals Association of Strong Immune Responses to PPE Protein Rv1168c with Active Tuberculosis

2008 ◽  
Vol 15 (6) ◽  
pp. 974-980 ◽  
Author(s):  
Nooruddin Khan ◽  
Kaiser Alam ◽  
Shiny Nair ◽  
Vijaya Lakshmi Valluri ◽  
Kolluri J. R. Murthy ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Tuberculin Test ◽  
Interferon Response ◽  
Peripheral Blood Mononuclear ◽  
Purified Protein Derivative ◽  
Conventional Tests ◽  
Immunodominant Antigens ◽  
Smear Negative ◽  
And Control ◽  
Immunogenic Properties

ABSTRACT Accurate diagnosis of tuberculosis (TB) infection is critical for the treatment, prevention, and control of TB. Conventional diagnostic tests based on purified protein derivative (PPD) do not achieve the required diagnostic sensitivity. Therefore, in this study, we have evaluated the immunogenic properties of Rv1168c, a member of the PPE family, in comparison with PPD, which is routinely used in the tuberculin test, and Hsp60 and ESAT-6, well-known immunodominant antigens of Mycobacterium tuberculosis. In a conventional enzyme immunoassay, the recombinant Rv1168c protein displayed stronger immunoreactivity against the sera obtained from patients with clinically active TB than did PPD, Hsp60, or ESAT-6 and could distinguish TB patients from Mycobacterium bovis BCG-vaccinated controls. Interestingly, Rv1168c antigen permits diagnosis of smear-negative pulmonary TB as well as extrapulmonary TB cases, which are often difficult to diagnose by conventional tests. The immunodominant nature of Rv1168c makes it a promising candidate to use in serodiagnosis of TB. In addition, our studies also show that Rv1168c is a potent T-cell antigen which elicits a strong gamma interferon response in sensitized peripheral blood mononuclear cells obtained from TB patients.

Identification of Molecular Mechanisms in Parkinson’s Disease Pathogenesis: Significance of Survival and Inflammation Pathways

2020 ◽  
Author(s):  
Zerrin Karaaslan ◽  
Ozlem Timirci Kahraman ◽  
Elif Sanli ◽  
Hayriye Arzu Ergen ◽  
Basar Bilgic ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Functional Annotation ◽  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Neuronal Degeneration ◽  
Expression Profiles ◽  
Quantitative Polymerase Chain Reaction ◽  
Rt Pcr ◽  
Peripheral Blood Mononuclear

Abstract Background: Our aim was to identify the differentially expressed genes (DEGs) between Parkinson’s disease (PD) patients and controls by microarray technology and analysis of related molecular pathways by functional annotation. Methods: Thirty PD patients and 30 controls were enrolled. Agilent Human 8X60 K Oligo Microarray was used for gene level expression identification. Gene ontology and pathway enrichment analyses were used for functional annotation of DEGs. Protein-protein interaction analyses were performed with STRING. Expression levels of randomly selected 5 genes among DEGs were quantified by real time quantitative polymerase chain reaction (RT-PCR) for validation. Flow cytometry was done to determine frequency of regulatory T cells (Tregs) in peripheral blood mononuclear cells. Results: A total of 361 DEGs (143 upregulated and 218 downregulated) were identified after GeneSpring analysis. DEGs were involved in 28 biological processes, 12 cellular components and 26 molecular functions. Pathway analyses demonstrated that upregulated genes mainly enriched in p53 (CASP3, TSC2, ATR, MDM4, CCNG1) and PI3K/Akt (IL2RA, IL4R, TSC2, VEGFA, PKN2, PIK3CA, ITGA4, BCL2L11) signaling pathways. TP53 and PIK3CA were identified as most significant hub proteins. Expression profiles obtained by RT-PCR were consistent with microarray findings. PD patients showed increased proportions of CD49d+ Tregs, which correlated with disability scores. Discussion: Survival pathway genes were upregulated putatively to compensate neuronal degeneration. Bioinformatics analysis showed an association between survival and inflammation genes. Increased CD49d+ Treg ratios might signify the attempt of the immune system to suppress ongoing inflammation. Conclusion: Altered functions of Tregs might have an important role in PD pathogenesis and CD49d expression could be a prognostic biomarker of PD.

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