Constitutive apoptosis in equine peripheral blood neutrophils in vitro

Autophagy pathways play an important role in immunity and inflammation via pathogen clearance mechanisms mediated by immune cells, such as macrophages and neutrophils. In particular, autophagic activity is essential for the release of neutrophil extracellular traps (NETs), a distinct form of active neutrophil death. The current study set out to elucidate the mechanism of the NFIL3/REDD1/mTOR axis in neutrophil autophagy and NET formation during gout inflammation. Firstly, NFIL3 expression patterns were determined in the peripheral blood neutrophils of gout patients and monosodium urate (MSU)-treated neutrophils. Interactions between NFIL3 and REDD1 were identified. In addition, gain- or loss-of-function approaches were used to manipulate NFIL3 and REDD1 in both MSU-induced neutrophils and mice. The mechanism of NFIL3 in inflammation during gout was evaluated both in vivo and in vitro via measurement of cell autophagy, NET formation, MPO activity as well as levels of inflammatory factors. NFIL3 was highly-expressed in both peripheral blood neutrophils from gout patients and MSU-treated neutrophils. NFIL3 promoted the transcription of REDD1 by binding to its promoter. REDD1 augmented neutrophil autophagy and NET formation by inhibiting the mTOR pathway. In vivo experimental results further confirmed that silencing of NFIL3 reduced the inflammatory injury of acute gouty arthritis mice by inhibiting the neutrophil autophagy and NET formation, which was associated with down-regulation of REDD1 and activation of the mTOR pathway. Taken together, NFIL3 can aggravate the inflammatory reaction of gout by stimulating neutrophil autophagy and NET formation via REDD1/mTOR, highlighting NFIL3 as a potential therapeutic target for gout.

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Downregulation of blood and bone marrow neutrophils decreases expression of acute lung injury in sheep

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1992.263.5.h1492 ◽

1992 ◽

Vol 263 (5) ◽

pp. H1492-H1498

Author(s):

P. J. McKenna ◽

D. L. Rosolia ◽

Y. Ishihara ◽

K. H. Albertine ◽

N. C. Staub ◽

...

Keyword(s):

Bone Marrow ◽

Acute Lung Injury ◽

Lung Injury ◽

Peripheral Blood ◽

Pulmonary Circulation ◽

Tissue Injury ◽

Blood Neutrophils ◽

Superoxide Release

We have shown that infusion of zymosan-activated plasma (ZAP) in sheep causes acute lung injury and downregulates peripheral blood neutrophils in that elicited superoxide release is reduced for at least 24 h after the infusion. The present study was designed to test the following hypotheses: 1) peripheral blood neutrophils are representative of neutrophils marginated in the pulmonary circulation, 2) blood neutrophils are downregulated because neutrophils developing in bone marrow are similarly affected, and 3) downregulated neutrophils have a reduced capacity to produce tissue injury. In a series of experiments in 21 sheep, we showed that elicited superoxide release was similar in peripheral blood neutrophils and in marginated neutrophils washed out of the pulmonary vascular bed. Measurements of superoxide release from blood and bone marrow neutrophils collected 2-24 h after ZAP infusion revealed progressive downregulation with time and greater downregulation of superoxide release in bone marrow neutrophils compared with peripheral blood neutrophils. Finally, after downregulating peripheral blood neutrophils, subsequent infusion of ZAP in conscious sheep produced sequestration of neutrophils in the pulmonary circulation but failed to produce a sustained increase in lung lymph protein clearance. The results suggest that neutrophil downregulation, as measured in vitro, is expressed in vivo as reduced ability of neutrophils to produce tissue injury when challenged by an activating agent.

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FATE OF NON-VIRULENT GROUP A STREPTOCOCCI PHAGOCYTIZED BY HUMAN AND MOUSE NEUTROPHILS

Journal of Experimental Medicine ◽

10.1084/jem.106.6.777 ◽

1957 ◽

Vol 106 (6) ◽

pp. 777-786 ◽

Cited By ~ 10

Author(s):

Armine T. Wilson ◽

Grove G. Wiley ◽

Pauline Bruno

Keyword(s):

Electric Current ◽

Peripheral Blood ◽

Group A Streptococci ◽

Blood Neutrophils ◽

Group A ◽

Time Required ◽

Human And Mouse ◽

Virulent Group

The fate of non-virulent group A streptococci phagocytized in vitro has been investigated by destroying the phagocyte with electric current and observing whether the liberated cocci multiply. Human and mouse peripheral blood neutrophils quickly injure ingested cocci, the time required to produce 50 per cent non-survival of chains being 8 and 6¾ minutes, respectively.

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Effect of In Vitro Cold Exposure on Phagocytic Activity of Human Peripheral Blood Neutrophils

Bulletin of Experimental Biology and Medicine ◽

10.1007/s10517-015-2910-0 ◽

2015 ◽

Vol 159 (1) ◽

pp. 142-145

Author(s):

T. V. Polezhaeva ◽

O. O. Zaitseva ◽

A. N. Khudyakov ◽

O. N. Solomina

Keyword(s):

Cold Exposure ◽

Peripheral Blood ◽

Phagocytic Activity ◽

Human Peripheral Blood ◽

Blood Neutrophils

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In vitro effects of GM-CSF on mature peripheral blood neutrophils.

International Journal of Molecular Medicine ◽

10.3892/ijmm.1.6.943 ◽

1998 ◽

Cited By ~ 3

Author(s):

G Fossati ◽

I Mazzucchelli ◽

D Gritti ◽

G Ricevuti ◽

S W Edwards ◽

...

Keyword(s):

Peripheral Blood ◽

Gm Csf ◽

Blood Neutrophils ◽

In Vitro Effects

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Expression of CD4 on human peripheral blood neutrophils

Blood ◽

10.1182/blood-2002-10-3056 ◽

2003 ◽

Vol 101 (11) ◽

pp. 4452-4456 ◽

Cited By ~ 40

Author(s):

Priscilla Biswas ◽

Barbara Mantelli ◽

Antonio Sica ◽

Mauro Malnati ◽

Carla Panzeri ◽

...

Keyword(s):

T Lymphocytes ◽

Peripheral Blood ◽

Mononuclear Cells ◽

Human Peripheral Blood ◽

Human Herpesvirus ◽

Peripheral Blood Mononuclear ◽

Similar Frequency ◽

Blood Neutrophils ◽

Hiv 1

Abstract CD4, the primary receptor for entry of HIV, is known to be expressed on T cells and monocytes/macrophages; healthy natural killer (NK) lymphocytes; in vitro human herpesvirus 6 (HHV6)–infected CD8+, NK, and γδ T lymphocytes; CD34+ progenitor cells; and a subset of eosinophils and basophils. We here report the unconventional expression of CD4 at the surface of peripheral blood neutrophils derived from 4 of 51 (7.8%) HIV-1–infected and 3 of 25 (12%) uninfected donors, with similar frequency within the 2 groups. The percentage of CD4+ neutrophils ranged from 39% to 97% of the total neutrophil population. Both surface and cytoplasmic forms of CD4 were present in neutrophils. Quantitative RNA polymerase chain reaction (PCR) revealed that neutrophils contain levels of CD4 mRNA comparable to those of peripheral blood mononuclear cells derived from the same donor. The conformation of CD4 expressed at the surface of neutrophils was similar to that of CD4 expressed on T lymphocytes as determined by the binding of monoclonal antibodies specific for conformational epitopes and the binding of recombinant HIV-1 gp120. Thus, our data provide evidence that neutrophils express endogenous CD4 and bind HIV. Owing to their abundance in peripheral blood, CD4+ neutrophils may influence significantly the biodistribution of HIV delivering it to sites of inflammation or to additional tissue reservoirs.

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Downmodulation of IL-8 receptors, type A and type B, on human lung neutrophils in vivo

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1997.273.3.l618 ◽

1997 ◽

Vol 273 (3) ◽

pp. L618-L625 ◽

Cited By ~ 3

Author(s):

K. Soejima ◽

S. Fujishima ◽

H. Nakamura ◽

Y. Waki ◽

M. Nakamura ◽

...

Keyword(s):

Peripheral Blood ◽

Type A ◽

Type B ◽

Low Level ◽

Blood Neutrophils ◽

Vitro Analysis ◽

High Level ◽

In Vitro Analysis

We examined the expression of interleukin (IL)-8 receptors (Rs), type A (IL-8-RA) and type B (IL-8-RB), on peripheral blood and bronchoalveolar lavage (BAL) fluid neutrophils; we also examined IL-8 and other chemoattractants in the epithelial lining fluid (ELF) of patients with chronic lower respiratory tract infection (CLI) to elucidate the in vivo regulation of IL-8Rs. Neutrophils were stained with monoclonal antibodies specific for IL-8-RA and IL-8-RB. We detected higher levels of IL-8 (81.6 +/- 25.4 ng/ml, mean +/- SE), leukotriene (LT) B4, and IL-1 beta in the ELF of the CLI patients than in their serum (P < 0.05). The expression of IL-8Rs on BAL neutrophils was significantly lower than that on peripheral blood neutrophils (P < 0.01 for both). In vitro analysis showed that low-level IL-8 (50 ng/ml) alone did not affect IL-8R expression but that it was downregulated by high-level IL-8 (500 ng/ml) alone and by low-level IL-8 in combination with LTB4 or IL-1 beta. Staurosporine reduced the downmodulation by low-level IL-8 plus LTB4 or IL-1 beta but not by high-level IL-8 alone. We speculate that pulmonary IL-8-RA and IL-8-RB may have been downmodulated by the combined effect of local chemoattractants through, in part, a protein kinase C-dependent mechanism.

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Neutrophils dominate in opsonic phagocytosis of P. falciparum blood-stage merozoites and protect against febrile malaria

Communications Biology ◽

10.1038/s42003-021-02511-5 ◽

2021 ◽

Vol 4 (1) ◽

Cited By ~ 1

Author(s):

Asier Garcia-Senosiain ◽

Ikhlaq Hussain Kana ◽

Subhash Singh ◽

Manoj Kumar Das ◽

Morten Hanefeld Dziegiel ◽

...

Keyword(s):

Peripheral Blood ◽

Blood Stage ◽

Peripheral Blood Leukocytes ◽

Phagocytic Cells ◽

Blood Leukocytes ◽

Fc Gamma Receptor ◽

Gamma Receptor ◽

Blood Neutrophils ◽

Antibody Levels

AbstractAntibody-mediated opsonic phagocytosis (OP) of Plasmodium falciparum blood-stage merozoites has been associated with protection against malaria. However, the precise contribution of different peripheral blood phagocytes in the OP mechanism remains unknown. Here, we developed an in vitro OP assay using peripheral blood leukocytes that allowed us to quantify the contribution of each phagocytic cell type in the OP of merozoites. We found that CD14 + +CD16− monocytes were the dominant phagocytic cells at very low antibody levels and Fc gamma receptor (FcγR) IIA plays a key role. At higher antibody levels however, neutrophils were the main phagocytes in the OP of merozoites with FcγRIIIB acting synergistically with FcγRIIA in the process. We found that OP activity by neutrophils was strongly associated with protection against febrile malaria in longitudinal cohort studies performed in Ghana and India. Our results demonstrate that peripheral blood neutrophils are the main phagocytes of P. falciparum blood-stage merozoites.

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Inflammatory Cytokines Enhance the Interaction of Mannheimia haemolytica Leukotoxin with Bovine Peripheral Blood Neutrophils In Vitro

Infection and Immunity ◽

10.1128/iai.70.8.4336-4343.2002 ◽

2002 ◽

Vol 70 (8) ◽

pp. 4336-4343 ◽

Cited By ~ 34

Author(s):

F. Leite ◽

S. O'Brien ◽

M. J. Sylte ◽

T. Page ◽

D. Atapattu ◽

...

Keyword(s):

Inflammatory Cytokines ◽

Peripheral Blood ◽

Biological Response ◽

Lymphocyte Function ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Blood Neutrophils ◽

Ifn Γ ◽

Bovine Pneumonic Pasteurellosis

ABSTRACT Mannheimia (Pasteurella) haemolytica A1 produces several virulence factors that play an important role in the pathogenesis of bovine pneumonic pasteurellosis. Foremost among these is a leukotoxin (LKT) that specifically kills ruminant leukocytes. Recent evidence suggests that M. haemolytica LKT binding to bovine leukocytes is mediated by the β2-integrin CD11a/CD18 (lymphocyte function-associated antigen 1 [LFA-1]), which subsequently induces activation and cytolysis of these cells. Inflammatory cytokines, which are released during viral and bacterial infection, are reported to increase LFA-1 expression and conformational activation. We investigated the effects of the inflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) on the interaction of M. haemolytica LKT with bovine peripheral blood neutrophils (PMNs). In this study we demonstrated, by flow cytometry, that bovine PMNs increased their binding to an anti-bovine LFA-1 monoclonal antibody (BAT75A) following in vitro incubation with IL-1β, TNF-α, or IFN-γ. Incubation with cytokines also increased CD18 expression, as assessed by real-time PCR and by Western blotting. Increased LFA-1 expression by PMNs exposed to cytokines was associated with increased LKT binding and cytotoxicity. The latter represented, at least in part, enhanced PMN apoptosis, as assessed by propidium iodine staining and caspase-3 activation. The results of this study suggest that inflammatory cytokines may play an important role in enhancing the biological response of bovine PMNs to M. haemolytica LKT.

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