scholarly journals Antibody-dependent eosinophil-mediated damage to 51Cr-labeled schistosomula of Schistosoma mansoni: damage by purieid eosinophils.

1977 ◽  
Vol 145 (1) ◽  
pp. 136-150 ◽  
Author(s):  
A E Butterworth ◽  
J R David ◽  
D Franks ◽  
A A Mahmoud ◽  
P H David ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Cell Types ◽  
Blood Leukocytes ◽  
Normal Individuals ◽  
Dependent Cell ◽  
A Cell ◽  
Relationship Of

After earlier observations that antibody-dependent, cell-mediated damage to 51Cr-labeled schistosomula can be ablated by pretreatment of a mixed preparation of human peripheral blood leukocytes with an anti-eosinophil serum and complement, we investigated the cytotoxic effects of eosinophil-enriched cell preparations. Preparations containing up to 98.5% eosinophils and devoid of neutrophils were effective in mediating antibody-dependent damage to schistosomula. Preparations enriched in mononuclear cells or in neutrophils, and devoid of eosinophils, were inactive. Eosinophils from some patients with eosinophilia induced by schistosomiasis were less active on a cell-to-cell basis than cells from normal individuals. The possibility that such cells were initially blocked by immune complexes was considered, and it was found that reasonable cytotoxicity by purified eosinophils from patients with eosinophilia could be generated by overnight cultures. A possible requirement for cooperation between eosinophils and other cell types was also studied. Lymphocytes, neutrophils and monocytes failed to enhance eosinophil-mediated cytotoxicity. These results provide further evidence that the eosinophil is the only cell in man responsible for antibody-dependent, complement-independent damage to schistosomula in vitro. Eosinophils from individuals, however, differ in their cytotoxic potential by a mechanism yet to be elucidated. The possible relationship of these findings to immunity in vivo is discussed.

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.

scholarly journals Innate triggering and antiviral effector functions of activin A

2021 ◽  
Author(s):  
Kinda Al-Hourani ◽  
Narayan Ramamurthy ◽  
Emanuele Marchi ◽  
Ruth M Eichinger ◽  
Lian N Lee ◽  
...  
Keyword(s):  
Viral Infection ◽  
Influenza A ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Activin A ◽  
Type I ◽  
Type I Ifn ◽  
Effector Functions

First-line defence against viral infection is contingent upon rapid detection of conserved viral structural and genomic motifs by germline-encoded pattern recognition receptors, followed by activation of the type I IFN system and establishment of an intracellular antiviral state. Novel antiviral functions of bone morphogenetic protein and related activin cytokines, acting in conjunction with, and independently of, type I IFN, have recently been described. Activin A mediates multiple innate and adaptive immune functions, including antiviral effects. However, how such effects are mediated and how activin might be triggered by viral infection have not been defined. Here we addressed this in vivo and in vitro, in humans and mice. Transcriptomic analyses delineated strikingly congruent patterns of gene regulation in hepatocytes stimulated with recombinant activin A and IFNα in vitro. Activin A mRNA, encoded by INHBA, is induced upon activation of RIG-I, MDA5 and TLR7/8 viral nucleic acid sensors in vitro, across multiple cell lines and in human peripheral blood mononuclear cells. In vivo, infection of mice with influenza A also upregulated Inhba mRNA in the lung; this local upregulation of Inhba is retained in MAVS knockout mice, indicating a role for non-RIG-I-like receptors in its induction. Activin induction and signalling were also detectable in patients with chronic viral hepatitis. Together, these data suggest Activin A is triggered in parallel with type I IFN responses and can trigger related antiviral effector functions. This model has implications for the development of targeted antiviral therapies, in addition to revealing novel facets of activin biology.

scholarly journals Differential Infectivity and Division ofToxoplasma gondii in Human Peripheral Blood Leukocytes

2000 ◽  
Vol 68 (8) ◽  
pp. 4822-4826 ◽  
Author(s):  
Jacqueline Y. Channon ◽  
Rosanne M. Seguin ◽  
Lloyd H. Kasper
Keyword(s):  
Dendritic Cells ◽  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Cell Types ◽  
Peripheral Blood Leukocytes ◽  
Blood Leukocytes ◽  
Differential Infectivity

ABSTRACT When tachyzoites were incubated with human peripheral blood leukocytes in vitro, more monocytes and dendritic cells than neutrophils or lymphocytes were infected. Although tachyzoites were able to divide in each of these cell types, monocytes and dendritic cells were more permissive to rapid tachyzoite division than neutrophils or lymphocytes.

Simvastatin Suppresses Interleukin Iβ Release in Human Peripheral Blood Mononuclear Cells Stimulated With Cholesterol Crystals

2018 ◽  
Vol 23 (6) ◽  
pp. 509-517 ◽  
Author(s):  
Anna J. Boland ◽  
Nisha Gangadharan ◽  
Pierce Kavanagh ◽  
Linda Hemeryck ◽  
Jennifer Kieran ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Peripheral Blood Mononuclear Cells ◽  
Nlrp3 Inflammasome ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

Statins are mainstream therapy in the treatment and prevention of cardiovascular disease through inhibitory effects on cholesterol synthesis. However, statins’ beneficial effects in cardiovascular disease may also be attributable to their role as anti-inflammatory mediators. Here, we investigated the effects of simvastatin treatment on expression levels of interleukin (IL) 1β in both patient with hyperlipidemia and healthy human peripheral blood mononuclear cells (PBMCs) using cholesterol crystals (CC), a cardiovascular pathogenic stimulus for activation of the NOD-like receptor pyrin domain–containing protein 3 (NLRP3) inflammasome. Cholesterol crystal-induced NLRP3 inflammasome activation was used to trigger maturation and release of IL-1β in PBMCs. Specifically, isolated PBMCs from patients with hyperlipidemia at baseline and following 8 weeks of in vivo treatment with simvastatin (10-20 mg) daily were stimulated with lipopolysaccharide (LPS; 100 ng/mL) for 3 hours to induce proIL-Iβ expression followed by CC (2 mg/mL) stimulation for further 18 hours to activate the NLRP3 inflammasome complex to induce maturation/activation of IL-1β. Peripheral blood mononuclear cells were also isolated from healthy donors and stimulated in vitro with simvastatin (50, 25, 5, and 2 µmol/L) prior to stimulation with LPS and CC as described above. The effects of simvastatin treatment on levels of IL-1β expression were determined by enzyme-linked immunosorbent assay and western blot. Both in vitro and in vivo treatments with simvastatin led to a significant reduction in the levels of expression of IL-1β in response to stimulation with CC. Simvastatin inhibits the expression and activation of IL-1β induced by CC in PBMCs, which may contribute to its protective role in patients with cardiovascular disease.

Neopterin suppresses the activity of tryptophan-degrading enzyme indoleamine 2,3-dioxygenase in human peripheral blood mononuclear cells

Pteridines ◽  
2013 ◽  
Vol 24 (3) ◽  
pp. 237-243
Author(s):  
Sebastian Schroecksnadel ◽  
Elena-Sophia Ledjeff ◽  
Johanna Gostner ◽  
Christiana Winkler ◽  
Katharina Kurz ◽  
...  
Keyword(s):  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Peripheral Blood Mononuclear ◽  
Indoleamine 2,3 Dioxygenase ◽  
Blood Mononuclear Cells ◽  
Ifn Γ

AbstractIn vitro, large amounts of neopterin are released from human monocyte-derived macrophages and dendritic cells primarily upon stimulation with Th1-type cytokine interferon-γ (IFN-γ). IFN-γ also induces the enzyme indoleamine 2,3-dioxygenase (IDO), which degrades tryptophan (TRP) to form kynurenine (KYN). IDO-mediated TRP catabolism is very effective in suppressing the proliferation of T lymphocytes as well as of pathogens in vitro and in vivo. In this study, we investigated whether exogenously added neopterin may influence IDO activity in resting and in stimulated peripheral blood mononuclear cells (PBMC). PBMC were isolated from healthy donors, and neopterin was added in a concentration range from 0.01 to 50 μmol/L. After 30 min, PBMC were stimulated or not with 10 μg/mL of mitogen phytohemagglutinin (PHA). After 48 h, culture supernatants were collected, KYN and TRP concentrations were measured by high-performance liquid chromatography, and the ratio of KYN vs. TRP was calculated as an estimate of IDO activity. Spontaneous as well as PHA-induced TRP breakdown was suppressed by exogenously added neopterin in a dose-dependent way; the lowest active concentration of neopterin was <100 nmol/L. As neopterin concentrations in the nanomolar range are commonly observed in patients suffering from infections, sepsis, or uremia, our results suggest that neopterin formation might also serve as a feedback mechanism to slow down TRP degradation in vivo.

SGX70393 Inhibits Bcr-AblT315I In Vitro and In Vivo and Completely Suppresses Resistance When Combined with Nilotinib or Dasatinib.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 535-535 ◽  
Author(s):  
Thomas O’Hare ◽  
Christopher A. Eide ◽  
Jeffrey W. Tyner ◽  
Amie S. Corbin ◽  
Matthew J. Wong ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mononuclear Cells ◽  
Kinase Inhibitor ◽  
Single Agent ◽  
Resistance Profile ◽  
Murine Bone Marrow ◽  
Abl Kinase ◽  
A Cell

Abstract Overview: Bcr-AblT315I is detected in the majority of CML patients who relapse after dasatinib- or nilotinib-based second-line Bcr-Abl kinase inhibitor therapy. SGX70393, an azapyridine-based Abl kinase inhibitor, is effective against Bcr-Abl and Bcr-AblT315I at low nanomolar concentrations in vitro and in cell lines. Here, we comprehensively profiled SGX70393 against native and mutant Bcr-Abl in vitro and in vivo. We also used a cell-based mutagenesis screen to evaluate the resistance profile of SGX70393 alone and in combination with imatinib, nilotinib, or dasatinib. Methods: We assessed colony formation in the presence of SGX70393 by murine bone marrow infected with retroviruses for expression of Bcr-Abl, Bcr-AblT315I, or a variety of other mutants. Toxicity was tested in clonogenic assays of normal bone marrow. SGX70393 effects on cellular tyrosine phosphorylation were measured by immunoblot and FACS in primary Bcr-AblT315I cells isolated from patients with CML or Ph+ B-ALL. In vivo activity was evaluated in a xenograft model using Ba/F3 cells expressing Bcr-AblT315I. Lastly, the resistance profile of SGX70393 was evaluated alone and in dual combinations with imatinib, nilotinib, or dasatinib in a cell-based mutagenesis assay. Results: Colony formation by murine bone marrow cells expressing Bcr-AblT315I (IC50: 180 nM) was reduced by SGX70393 in a dose dependent manner, while no toxicity was observed in colony forming assays of normal human or murine mononuclear cells at concentrations up to 2 μM. Ex vivo exposure of human Bcr-AblT315I mononuclear cells to SGX70393 decreased CrkL phosphorylation, while imatinib, nilotinib, or dasatinib had no effect. SGX70393 inhibited Bcr-AblT315I-driven tumor growth in mice and this was correlated with reduced levels of pCrkL in tumor tissue, while imatinib was ineffective. A cell-based mutagenesis screen revealed a profile of resistant clones confined to four p-loop residues and position 317. SGX70393 in combination with imatinib contracted the spectrum of resistant mutations relative to either single agent, though outgrowth could not be completely suppressed. Combining SGX70393 with low concentrations of nilotinib or dasatinib narrowed the resistance profile still further (residues 248 and 255 for nilotinib; 317 for dasatinib) and, with clinically achievable doses of either second drug, completely abrogated emergence of resistant subclones. Conclusions: SGX70393, a potent inhibitor of Bcr-AblT315I, exhibits a resistance profile centered around the p-loop and residue 317 of Bcr-Abl. Remarkably, in combination with nilotinib or dasatinib, outgrowth of resistant clones is completely suppressed. Single-agent therapy with an effective T315I inhibitor may provide a viable option for patients who relapse with Bcr-AblT315I. However, as a broader spectrum of mutations accounts for imatinib resistance, patients with acquired dasatinib or nilotinib resistance may continue to harbor residual mutant clones other than T315I. Thus, the full clinical potential of SGX70393 may be realized in combinations with a second Abl kinase inhibitor. Our findings provide the first demonstration that Abl kinase inhibitor combinations that include a T315I-targeted component such as SGX70393 have the potential to pre-empt Bcr-Abl-dependent resistance.

scholarly journals SIMILARITY OF THE KINETICS OF INVERTASE ACTION IN VIVO AND IN VITRO. III

1933 ◽  
Vol 16 (4) ◽  
pp. 571-577 ◽  
Author(s):  
J. M. Nelson ◽  
B. G. Wilkes
Keyword(s):  
Physiological Activity ◽  
Water Concentration ◽  
Invertase Activity ◽  
Yeast Cells ◽  
Identical Manner ◽  
A Cell ◽  
Relationship Of ◽  
The Relationship

1. The relationship of sucrose and water concentration to invertase activity in vivo and in vitro has been studied under the same environmental conditions. 2. The sucroclastic activity of S. cerevisiae cells and of invertase solutions prepared from them reacts to changes in sucrose and water concentration in an identical manner. 3. The invertase contained in living yeast cells is just as freely exposed to the conditions of sucrose and water concentrations of the suspending medium as it would be if it were contained in a cell-free solution. Weight is added to the previous suggestion (2) that yeast invertase exerts its physiological activity in a region quite close to the surface of the cell.

scholarly journals Inhibition of Fumarate Reductase inLeishmania major and L. donovani by Chalcones

2001 ◽  
Vol 45 (7) ◽  
pp. 2023-2029 ◽  
Author(s):  
Ming Chen ◽  
Lin Zhai ◽  
Søren Brøgger Christensen ◽  
Thor G. Theander ◽  
Arsalan Kharazmi
Keyword(s):  
Respiratory Chain ◽  
Mammalian Cells ◽  
Leishmania Major ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Fumarate Reductase ◽  
Peripheral Blood Mononuclear ◽  
Licochalcone A

ABSTRACT Our previous studies have shown that chalcones exhibit potent antileishmanial and antimalarial activities in vitro and in vivo. Preliminary studies showed that these compounds destroyed the ultrastructure of Leishmania parasite mitochondria and inhibited the respiration and the activity of mitochondrial dehydrogenases of Leishmania parasites. The present study was designed to further investigate the mechanism of action of chalcones, focusing on the parasite respiratory chain. The data show that licochalcone A inhibited the activity of fumarate reductase (FRD) in the permeabilized Leishmania major promastigote and in the parasite mitochondria, and it also inhibited solubilized FRD and a purified FRD from L. donovani. Two other chalcones, 2,4-dimethoxy-4′-allyloxychalcone (24m4ac) and 2,4-dimethoxy-4′-butoxychalcone (24mbc), also exhibited inhibitory effects on the activity of solubilized FRD in L. majorpromastigotes. Although licochalcone A inhibited the activities of succinate dehydrogenase (SDH), NADH dehydrogenase (NDH), and succinate- and NADH-cytochrome c reductases in the parasite mitochondria, the 50% inhibitory concentrations (IC50) of licochalcone A for these enzymes were at least 20 times higher than that for FRD. The IC50 of licochalcone A for SDH and NDH in human peripheral blood mononuclear cells were at least 70 times higher than that for FRD. These findings indicate that FRD, one of the enzymes of the parasite respiratory chain, might be the specific target for the chalcones tested. Since FRD exists in the Leishmaniaparasite and does not exist in mammalian cells, it could be an excellent target for antiprotozoal drugs.

scholarly journals Oncogene expression in autoimmune and normal peripheral blood mononuclear cells.

1986 ◽  
Vol 163 (5) ◽  
pp. 1292-1307 ◽  
Author(s):  
D M Klinman ◽  
J F Mushinski ◽  
M Honda ◽  
Y Ishigatsubo ◽  
J D Mountz ◽  
...  
Keyword(s):  
B Cells ◽  
Mononuclear Cells ◽  
Cell Types ◽  
Isolated Cells ◽  
Peripheral Blood Mononuclear ◽  
Normal Peripheral Blood ◽  
Additional Cell ◽  
Normal Controls

PBMC from patients with autoimmune diseases and from normal controls were studied for the expression of several cellular oncogenes. Gene expression was assessed by Northern blot analysis of poly(A)+ RNA obtained from leukapheresis samples. Patients with SLE expressed significantly more c-myc protooncogene RNA than did normal controls. Increased expression of the N-ras protooncogene was found in that subset of patients whose autoimmune disease was very active. Cells from individuals with SLE, but not from those with other autoimmune illnesses, showed significantly decreased levels of the c-myb and c-fos protooncogenes. To examine the implications of these findings, B and T cells were purified from apheresis samples donated by normal volunteers. When mitogen was used to activate the B cells in vitro, their pattern of protooncogene expression changed to resemble that found in freshly isolated cells from lupus patients. These results suggest that the differences detected in the expression of protooncogenes by patients with SLE may be due to the abnormal activation of their B cells in vivo. The pattern of protooncogene expression found in patients with other autoimmune illnesses is consistent with the activation of additional cell types in those diseases.

Sign in / Sign up

Export Citation Format

Share Document