scholarly journals Serotonin storage pools in basophil leukemia and mast cells: characterization of two types of serotonin binding protein and radioautographic analysis of the intracellular distribution of [3H]serotonin.

1982 ◽  
Vol 93 (3) ◽  
pp. 638-647 ◽  
Author(s):  
H Tamir ◽  
T C Theoharides ◽  
M D Gershon ◽  
P W Askenase
Keyword(s):  
Mast Cells ◽  
Storage Proteins ◽  
Binding Protein ◽  
Protein S ◽  
Intracellular Distribution ◽  
Con A ◽  
Intracellular Storage ◽  
Rbl Cells

We studied binding of serotonin to protein(s) derived from rat basophil leukemia (RBL) cells and mast cells. We found two types of serotonin binding protein in RBL cells. These proteins differed from one another in molecular weight and eluted in separate peaks from sephadex G-200 columns. Peak I protein (KD = 1.9 X 10(-6) M) was a glycoprotein that bound to concanavalin A (Con A); Peak II protein (KD1 = 4.5 X 10(-8) M; KD2 = 3.9 X 10(-6) M) did not bind to Con A. Moreover, binding of [3H]serotonin to protein of peak I was sensitive to inhibition by reserpine, while binding of [3H]serotonin to protein of peak II resisted inhibition by that drug. Other differences between the two types of binding protein were found, the most significant of which was the far more vigorous conditions of homogenization required to extract peak I than peak II protein. Neither peak I nor peak II protein resembled the serotonin binding protein (SBP) that is found in serotonergic neurons of the brain and gut. Electron microscope radioautographic analysis of the intracellular distribution of [3H]serotonin taken up in vitro by RBL cells or in vivo by murine mast cells indicated that essentially all of the labeled amine was located in cytoplasmic granules. No evidence for a pool in the cytosol was found and all granules were capable of becoming labeled. The presence of two types of intracellular serotonin binding proteins in these cells may indicate that there are two intracellular storage compartments for the amine. Both may be intragranular, but peak I protein may be associated with the granular membrane while peak II protein may be more free within the granular core. Different storage proteins may help to explain the differential release of amines from mast cell granules.

scholarly journals Multiple Functions of the Nonconserved N-Terminal Domain of Yeast TATA-Binding Protein

Genetics ◽  
2001 ◽  
Vol 158 (1) ◽  
pp. 87-93
Author(s):  
Mark Lee ◽  
Kevin Struhl
Keyword(s):  
Dna Binding ◽  
Binding Protein ◽  
Protein S ◽  
Tata Binding Protein ◽  
Terminal Region ◽  
Core Domain ◽  
Terminal Domain ◽  
Two Factors

Abstract The TATA-binding protein (TBP) is composed of a highly conserved core domain sufficient for TATA-element binding and preinitiation complex formation as well as a highly divergent N-terminal region that is dispensable for yeast cell viability. In vitro, removal of the N-terminal region domain enhances TBP-TATA association and TBP dimerization. Here, we examine the effects of truncation of the N-terminal region in the context of yeast TBP mutants with specific defects in DNA binding and in interactions with various proteins. For a subset of mutations that disrupt DNA binding and the response to transcriptional activators, removal of the N-terminal domain rescues their transcriptional defects. By contrast, deletion of the N-terminal region is lethal in combination with mutations on a limited surface of TBP. Although this surface is important for interactions with TFIIA and Brf1, TBP interactions with these two factors do not appear to be responsible for this dependence on the N-terminal region. Our results suggest that the N-terminal region of TBP has at least two distinct functions in vivo. It inhibits the interaction of TBP with TATA elements, and it acts positively in combination with a specific region of the TBP core domain that presumably interacts with another protein(s).

The Anticoagulant Properties of a Modified Form of Protein S

1988 ◽  
Vol 60 (02) ◽  
pp. 298-304 ◽  
Author(s):  
C A Mitchell ◽  
S M Kelemen ◽  
H H Salem
Keyword(s):  
Monoclonal Antibody ◽  
Anticoagulant Activity ◽  
Activated Protein C ◽  
Factor Xa ◽  
Protein S ◽  
Human Neutrophil Elastase ◽  
Factor X ◽  
Sds Page

SummaryProtein S (PS) is a vitamin K-dependent anticoagulant that acts as a cofactor to activated protein C (APC). To date PS has not been shown to possess anticoagulant activity in the absence of APC.In this study, we have developed monoclonal antibody to protein S and used to purify the protein to homogeneity from plasma. Affinity purified protein S (PSM), although identical to the conventionally purified protein as judged by SDS-PAGE, had significant anticoagulant activity in the absence of APC when measured in a factor Xa recalcification time. Using SDS-PAGE we have demonstrated that prothrombin cleavage by factor X awas inhibited in the presence of PSM. Kinetic analysis of the reaction revealed that PSM competitively inhibited factor X amediated cleavage of prothrombin. PS preincubated with the monoclonal antibody, acquired similar anticoagulant properties. These results suggest that the interaction of the monoclonal antibody with PS results in an alteration in the protein exposing sites that mediate the observed anticoagulant effect. Support that the protein was altered was derived from the observation that PSM was eight fold more sensitive to cleavage by thrombin and human neutrophil elastase than conventionally purified protein S.These observations suggest that PS can be modified in vitro to a protein with APC-independent anticoagulant activity and raise the possibility that a similar alteration could occur in vivo through the binding protein S to a cellular or plasma protein.

scholarly journals C4b-binding protein α-chain enhances antitumor immunity by facilitating the accumulation of tumor-infiltrating lymphocytes in the tumor microenvironment in pancreatic cancer

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Kosuke Sasaki ◽  
Shigetsugu Takano ◽  
Satoshi Tomizawa ◽  
Yoji Miyahara ◽  
Katsunori Furukawa ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Microenvironment ◽  
Binding Protein ◽  
Combined Treatment ◽  
Tumor Infiltrating Lymphocytes ◽  
Pdac Cell ◽  
Α Chain ◽  
Infiltrating Lymphocytes

Abstract Background Recent studies indicate that complement plays pivotal roles in promoting or suppressing cancer progression. We have previously identified C4b-binding protein α-chain (C4BPA) as a serum biomarker for the early detection of pancreatic ductal adenocarcinoma (PDAC). However, its mechanism of action remains unclear. Here, we elucidated the functional roles of C4BPA in PDAC cells and the tumor microenvironment. Methods We assessed stromal C4BPA, the C4BPA binding partner CD40, and the number of CD8+ tumor-infiltrating lymphocytes in resected human PDAC tissues via immunohistochemical staining. The biological functions of C4BPA were investigated in peripheral blood mononuclear cells (PBMCs) and human PDAC cell lines. Mouse C4BPA (mC4BPA) peptide, which is composed of 30 amino acids from the C-terminus and binds to CD40, was designed for further in vitro and in vivo experiments. In a preclinical experiment, we assessed the efficacy of gemcitabine plus nab-paclitaxel (GnP), dual immune checkpoint blockades (ICBs), and mC4BPA peptide in a mouse orthotopic transplantation model. Results Immunohistochemical analysis revealed that high stromal C4BPA and CD40 was associated with favorable PDAC prognosis (P=0.0005). Stromal C4BPA strongly correlated with the number of CD8+ tumor-infiltrating lymphocytes (P=0.001). In in vitro experiments, flow cytometry revealed that recombinant human C4BPA (rhC4BPA) stimulation increased CD4+ and CD8+ T cell numbers in PBMCs. rhC4BPA also promoted the proliferation of CD40-expressing PDAC cells. By contrast, combined treatment with gemcitabine and rhC4BPA increased PDAC cell apoptosis rate. mC4BPA peptide increased the number of murine T lymphocytes in vitro and the number of CD8+ tumor-infiltrating lymphocytes surrounding PDAC tumors in vivo. In a preclinical study, GnP/ICBs/mC4BPA peptide treatment, but not GnP treatment, led to the accumulation of a greater number of CD8+ T cells in the periphery of PDAC tumors and to greater tumor regression than did control treatment. Conclusions These findings demonstrate that the combination of GnP therapy with C4BPA inhibits PDAC progression by promoting antitumor T cell accumulation in the tumor microenvironment.

Imidazolidinyl urea activates mast cells via MRGPRX2 to induce non-histaminergic allergy

2021 ◽  
Author(s):  
Jiapan Gao ◽  
Delu Che ◽  
Xueshan Du ◽  
Yi Zheng ◽  
Huiling Jing ◽  
...  
Keyword(s):  
Contact Dermatitis ◽  
Mast Cells ◽  
Pharmaceutical Products ◽  
Drug Induced ◽  
Inflammatory Infiltration ◽  
Local Inflammatory Response ◽  
Allergic Contact ◽  
G Protein Coupled

Abstract Imidazolidinyl urea (IU) is used as an antimicrobial preservative in cosmetic and pharmaceutical products. IU induces allergic contact dermatitis, however, the mechanism has not yet been elucidated. Mas-related G protein-coupled receptor-X2 (MRGPRX2) triggers drug-induced pseudo-allergic reactions. The aims of this study were to determine whether IU activated mast cells through MRGPRX2 to further trigger contact dermatitis. Wild-type (WT) and KitW-sh/HNihrJaeBsmJNju (MUT) mice were treated with IU to observe its effects on local inflammation and mast cells degranulation in vivo. Laboratory of allergic disease 2 cells were used to detect calcium mobilization and release of inflammatory mediators in vitro. WT mice showed a severe local inflammatory response and contact dermatitis, whereas only slight inflammatory infiltration was observed in MUT mice. Thus, MRGPRX2 mediated the IU-induced activation of mast cells. However, histamine, a typical allergen, was not involved in this process. Tryptase expressed by mast cells was the major non-histaminergic inflammatory mediator of contact dermatitis. IU induced anaphylactic reaction via MRGPRX2 and further triggering non-histaminergic contact dermatitis, which explained why antihistamines are clinically ineffective against some chronic dermatitis.

scholarly journals Monocyte tissue factor induction by lipopolysaccharide (LPS): dependence on LPS-binding protein and CD14, and inhibition by a recombinant fragment of bactericidal/permeability-increasing protein

Blood ◽  
1994 ◽  
Vol 83 (9) ◽  
pp. 2516-2525 ◽  
Author(s):  
K Meszaros ◽  
S Aberle ◽  
R Dedrick ◽  
R Machovich ◽  
A Horwitz ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Binding Protein ◽  
Mononuclear Phagocytes ◽  
Factor Vii ◽  
Peripheral Blood Mononuclear ◽  
Recombinant Fragment

Abstract Mononuclear phagocytes, stimulated by bacterial lipopolysaccharide (LPS), have been implicated in the activation of coagulation in sepsis and endotoxemia. In monocytes LPS induces the synthesis of tissue factor (TF) which, assembled with factor VII, initiates the blood coagulation cascades. In this study we investigated the mechanism of LPS recognition by monocytes, and the consequent expression of TF mRNA and TF activity. We also studied the inhibition of these effects of LPS by rBPI23, a 23-kD recombinant fragment of bactericidal/permeability increasing protein, which has been shown to antagonize LPS in vitro and in vivo. Human peripheral blood mononuclear cells, or monocytes isolated by adherence, were stimulated with Escherichia coli O113 LPS at physiologically relevant concentrations (> or = 10 pg/mL). The effect of LPS was dependent on the presence of the serum protein LBP (lipopolysaccharide-binding protein), as shown by the potentiating effect of human recombinant LBP or serum. Furthermore, recognition of low amounts of LPS by monocytes was also dependent on CD14 receptors, because monoclonal antibodies against CD14 greatly reduced the LPS sensitivity of monocytes in the presence of serum or rLBP. Induction of TF activity and mRNA expression by LPS were inhibited by rBPI23. The expression of tumor necrosis factor showed qualitatively similar changes. Considering the involvement of LPS-induced TF in the potentially lethal intravascular coagulation in sepsis, inhibition of TF induction by rBPI23 may be of therapeutic benefit.

Induction of leukotriene production by bleomycin and asparaginase in mast cells in vitro and in patients in vivo

1998 ◽  
Vol 55 (4) ◽  
pp. 447-453 ◽  
Author(s):  
Susanne Geuenich ◽  
Christopher Haberl ◽  
Dietmar Egger ◽  
Uwe Kaspers ◽  
Lothar Hültner ◽  
...  
Keyword(s):  
Mast Cells

scholarly journals In vitro and in vivo evidence for actin association of the naphthylphthalamic acid-binding protein from zucchini hypocotyls

1998 ◽  
Vol 13 (3) ◽  
pp. 291-301 ◽  
Author(s):  
John H. Butler ◽  
Shiquan Hu ◽  
Shari R. Brady ◽  
Michael W. Dixon ◽  
Gloria K. Muday
Keyword(s):  
Binding Protein ◽  
Acid Binding Protein ◽  
Naphthylphthalamic Acid

scholarly journals Tethering DNA Damage Checkpoint Mediator Proteins Topoisomerase IIβ-binding Protein 1 (TopBP1) and Claspin to DNA Activates Ataxia-Telangiectasia Mutated and RAD3-related (ATR) Phosphorylation of Checkpoint Kinase 1 (Chk1)

2011 ◽  
Vol 286 (22) ◽  
pp. 19229-19236 ◽  
Author(s):  
Laura A. Lindsey-Boltz ◽  
Aziz Sancar
Keyword(s):  
Dna Damage ◽  
Ataxia Telangiectasia ◽  
Mammalian Cells ◽  
Binding Protein ◽  
Effector Proteins ◽  
Ataxia Telangiectasia Mutated ◽  
Checkpoint Kinase ◽  
Atr Kinase

The ataxia-telangiectasia mutated and RAD3-related (ATR) kinase initiates DNA damage signaling pathways in human cells after DNA damage such as that induced upon exposure to ultraviolet light by phosphorylating many effector proteins including the checkpoint kinase Chk1. The conventional view of ATR activation involves a universal signal consisting of genomic regions of replication protein A-covered single-stranded DNA. However, there are some indications that the ATR-mediated checkpoint can be activated by other mechanisms. Here, using the well defined Escherichia coli lac repressor/operator system, we have found that directly tethering the ATR activator topoisomerase IIβ-binding protein 1 (TopBP1) to DNA is sufficient to induce ATR phosphorylation of Chk1 in an in vitro system as well as in vivo in mammalian cells. In addition, we find synergistic activation of ATR phosphorylation of Chk1 when the mediator protein Claspin is also tethered to the DNA with TopBP1. Together, these findings indicate that crowding of checkpoint mediator proteins on DNA is sufficient to activate the ATR kinase.

scholarly journals The chromatin-binding protein HMGN3 stimulates histone acetylation and transcription across the Glyt1 gene

2012 ◽  
Vol 442 (3) ◽  
pp. 495-505 ◽  
Author(s):  
Gráinne Barkess ◽  
Yuri Postnikov ◽  
Chrisanne D. Campos ◽  
Shivam Mishra ◽  
Gokula Mohan ◽  
...  
Keyword(s):  
Histone Modifications ◽  
Splice Variants ◽  
Binding Protein ◽  
Histone H3 ◽  
Camp Response Element Binding ◽  
Element Binding Protein ◽  
H3k14 Acetylation ◽  
H3 Acetylation

HMGNs are nucleosome-binding proteins that alter the pattern of histone modifications and modulate the binding of linker histones to chromatin. The HMGN3 family member exists as two splice forms, HMGN3a which is full-length and HMGN3b which lacks the C-terminal RD (regulatory domain). In the present study, we have used the Glyt1 (glycine transporter 1) gene as a model system to investigate where HMGN proteins are bound across the locus in vivo, and to study how the two HMGN3 splice variants affect histone modifications and gene expression. We demonstrate that HMGN1, HMGN2, HMGN3a and HMGN3b are bound across the Glyt1 gene locus and surrounding regions, and are not enriched more highly at the promoter or putative enhancer. We conclude that the peaks of H3K4me3 (trimethylated Lys4 of histone H3) and H3K9ac (acetylated Lys9 of histone H3) at the active Glyt1a promoter do not play a major role in recruiting HMGN proteins. HMGN3a/b binding leads to increased H3K14 (Lys14 of histone H3) acetylation and stimulates Glyt1a expression, but does not alter the levels of H3K4me3 or H3K9ac enrichment. Acetylation assays show that HMGN3a stimulates the ability of PCAF [p300/CREB (cAMP-response-element-binding protein)-binding protein-associated factor] to acetylate nucleosomal H3 in vitro, whereas HMGN3b does not. We propose a model where HMGN3a/b-stimulated H3K14 acetylation across the bodies of large genes such as Glyt1 can lead to more efficient transcription elongation and increased mRNA production.

In-vitro and in-vivo Evaluation of Anti-asthmatic Activity of Eugenia jambolana bark

2021 ◽  
pp. 3337-3342
Author(s):  
Bhong Prabha N. ◽  
Naikawade Nilofar. S. ◽  
Mali Pratibha. R. ◽  
Bindu Madhavi. S.
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Animal Models ◽  
Aqueous Extract ◽  
Guinea Pigs ◽  
Bark Extract ◽  
Eugenia Jambolana ◽  
In Vivo Animal Models

Objectives: The present study designed to evaluate the Antiasthmatic activity of aqueous extract of bark of Eugenia Jambolana (AEEJ) on in vitro and in vivo animal models. Materials and methods: Different in vitro and in vivo animal models was used to study the anti asthmatic activity as isolated goat tracheal chain preparation, Acetylcholine and Histamine induced bronconstriction in guinea pigs, effect of drug extract on histamine release from mast cell was checked by clonidine-induced mast cell degranulation, and milk-induced eosinophilia and leukocytosis. Results: In-vitro study on goat tracheal chain preparation revealed that aqueous extract of Eugenia jambolana (AEEJ)bark exerted antagonistic effect on the histamine induced contraction. (P<0.05) The guinea pigs when exposed to 0.2% histamine aerosol showed signs of progressive dyspnoea leading to convulsions. AEEJ significantly prolonged the latent period of convulsions (PCT) as compared to control following the exposure of histamine (0.2%) aerosol (P<0.01). The observation of present study indicates aqueous extract of Eugenia jambolana shows significant inhibition of milk induced eosinophilia and leukocytosis. Group of animals pretreated with aqueous Eugenia jambolana bark extract showed significant reduction in degranulation of mast cells when challenged with clonidine. The prevention of degranulation process by the aqueous Eugenia jambolana bark extract (P<0.01) indicates a possible stabilizing effect on the mast cells, indicating mast cell stabilizing activity. Conclusions: Thus, AEEJ showed antihistaminic, mast cell stabilizing and protective in guinea pigs against histamine induced PCD, reduced eosinophilia and leukocytosis and hence possesses potential role in the treatment of asthma.

Sign in / Sign up

Export Citation Format

Share Document