scholarly journals Depletion of Neutrophils Exacerbates the Early Inflammatory Immune Response in Lungs of Mice Infected withParacoccidioides brasiliensis

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Paula Andrea Pino-Tamayo ◽  
Juan David Puerta-Arias ◽  
Damaris Lopera ◽  
Martha Eugenia Urán-Jiménez ◽  
Ángel González

Neutrophils predominate during the acute phase of theParacoccidioides brasiliensisinfection. Herein, we determined the role of the neutrophil during the early stages of experimental pulmonary paracoccidioidomycosis using a monoclonal antibody (mAb) specific for neutrophils. Male BALB/c mice were inoculated intranasally with1.5×106or2×106P. brasiliensisyeast cells. The mAb was administered 24 h before infection, followed by doses every 48 h until mice were sacrificed. Survival time was evaluated and mice were sacrificed at 48 h and 96 h after inoculation to assess cellularity, fungal load, cytokine/chemokine levels, and histopathological analysis. Neutrophils from mAb-treated mice were efficiently depleted (99.04%). Eighty percent of the mice treated with the mAb and infected with1.5×106yeast cells died during the first two weeks after infection. When mice were treated and infected with2×106yeast cells, 100% of them succumbed by the first week after infection. During the acute inflammatory response significant increases in numbers of eosinophils, fungal load and levels of proinflammatory cytokines/chemokines were observed in the mAb-treated mice. We also confirmed that neutrophils are an important source of IFN-γand IL-17. These results indicate that neutrophils are essential for protection as well as being important for regulating the early inflammatory immune response in experimental pulmonary paracoccidioidomycosis.

2015 ◽  
Vol 75 (2) ◽  
pp. 491-496 ◽  
Author(s):  
G. Dotta ◽  
J. Ledic-Neto ◽  
ELT. Gonçalves ◽  
A. Brum ◽  
M. Maraschin ◽  
...  

This study evaluated the acute inflammatory response induced by carrageenin in the swim bladder of Nile tilapia supplemented with the mixture of natural extracts of propolis and Aloe barbadensis (1:1) at a concentration of 0.5%, 1% and 2% in diet during 15 days. Thirty-six fish were distributed into four treatments with three replicates: fish supplemented with 0.5% of admix of extracts of propolis and Aloe (1:1) injected with 500 µg carrageenin; fish supplemented with 1% of admix of extracts of propolis and Aloe (1:1) injected with 500 µg carrageenin; fish supplemented with 2% of admix of extracts of propolis and Aloe (1:1), injected with 500 µg carrageenin and unsupplemented fish injected with 500 µg carrageenin. Six hours after injection, samples of blood and exudate from the swim bladder of fish were collected. It was observed an increase in the leukocyte count in the swim bladder exudate of fish supplemented with extracts of propolis and Aloe injected with carrageenin. The most frequent cells were macrophages followed by granular leukocytes, thrombocytes and lymphocytes. Supplementation with propolis and Aloe to 0.5% caused a significant increase in the number of cells on the inflammatory focus mainly macrophages, cells responsible for the phagocytic activity in tissues, agent of innate fish immune response.


2020 ◽  
Vol 1 (9) ◽  
pp. 64-71
Author(s):  
E. A. Klimov ◽  
◽  
E. K. Novitskaya ◽  
S. N. Koval’chuk ◽  
◽  
...  

Intercellular adhesion molecule CD209 (DC-SIGN) is a membrane C-type lectin receptor expressed on the surface of dendritic cells and macrophages. CD209 plays an important role in innate immunity. Many studies have shown the possibility of interaction of the CD209 molecule with a number of dangerous pathogens of humans and animals. This review summarizes information on the structure of the CD209 gene and its product, describes the role of the CD209 protein in the immune response, in the migration of dendritic cells from the blood to the tissue, and their interaction with neutrophils. The currently known signaling pathway of activation through the CD209 inflammatory response is presented. The role of CD209 as an endocytic antigen receptor and the participation of the protein in immune evasion of pathogens are discussed. The mechanisms known to date for the development of infections caused by pathogens of various nature in animals are described.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Paul T. King

Bronchiectasis is a prevalent respiratory condition characterised by permanent and abnormal dilation of the lung airways (bronchi). There are a large variety of causative factors that have been identified for bronchiectasis; all of these compromise the function of the immune response to fight infection. A triggering factor may lead to the establishment of chronic infection in the lower respiratory tract. The bacteria responsible for the lower respiratory tract infection are usually found as commensals in the upper respiratory tract microbiome. The consequent inflammatory response to infection is largely responsible for the pathology of this condition. Both innate and adaptive immune responses are activated. The literature has highlighted the central role of neutrophils in the pathogenesis of bronchiectasis. Proteases produced in the lung by the inflammatory response damage the airways and lead to the pathological dilation that is the pathognomonic feature of bronchiectasis. The small airways demonstrate infiltration with lymphoid follicles that may contribute to localised small airway obstruction. Despite aggressive treatment, most patients will have persistent disease. Manipulating the immune response in bronchiectasis may potentially have therapeutic potential.


2015 ◽  
Vol 74 (4) ◽  
pp. 786-790 ◽  
Author(s):  
Nicola Dalbeth ◽  
Bregina Pool ◽  
Odette M Shaw ◽  
Jacquie L Harper ◽  
Paul Tan ◽  
...  

2004 ◽  
Vol 72 (7) ◽  
pp. 3932-3940 ◽  
Author(s):  
Celina Arruda ◽  
Rita C. Valente-Ferreira ◽  
Adriana Pina ◽  
Suely S. Kashino ◽  
Raquel A. Fazioli ◽  
...  

ABSTRACT Resistance to paracoccidioidomycosis, the most important endemic mycosis in Latin America, is thought to be primarily mediated by cellular immunity and the production of gamma interferon. To assess the role of interleukin-4 (IL-4), a Th2 cytokine, pulmonary paracoccidioidomycosis in IL-4-depleted susceptible (B10.A) and intermediate (C57BL/6) mice was studied. Two different protocols were used to neutralize endogenous IL-4 in B10.A mice: 1 mg of anti-IL-4 monoclonal antibody (MAb)/week and 8 mg 1 day before intratracheal infection with 106 Paracoccidioides brasiliensis yeast cells. Unexpectedly, both protocols enhanced pulmonary infection but did not alter the levels of pulmonary cytokines and specific antibodies. Since in a previous work it was verified that C57BL/6 mice genetically deficient in IL-4 were more resistant to P. brasiliensis infection, we also investigated the effect of IL-4 depletion in this mouse strain. Treatment with the MAb at 1 mg/week led to less severe pulmonary disease associated with impaired synthesis of Th2 cytokines in the lungs and liver of control C57BL/6 mice. Conversely, in IL-4-depleted C57BL/6 mice, increased levels of tumor necrosis factor alpha and IL-12 were found in the lungs and liver, respectively. In addition, higher levels of immunoglobulin G2a (IgG2a) and lower levels of IgG1 antibodies were produced by IL-4-depleted mice than by control mice. Lung pathologic findings were equivalent in IL-4-depleted and untreated B10.A mice. In IL-4-depleted C57BL/6 mice, however, smaller and well-organized granulomas replaced the more extensive lesions that developed in untreated mice. These results clearly showed that IL-4 can have a protective or a disease-promoting effect in pulmonary paracoccidioidomycosis depending on the genetic background of the host.


2000 ◽  
Vol 68 (1) ◽  
pp. 352-359 ◽  
Author(s):  
Luz E. Cano ◽  
Lúcia M. Singer-Vermes ◽  
Tania A. Costa ◽  
José O. Mengel ◽  
Cynthia F. Xidieh ◽  
...  

ABSTRACT Using a pulmonary model of infection, we demonstrated previously that A/Sn and B10.A mice are, respectively, resistant and susceptible to Paracoccidioides brasiliensis infection. Employing the same experimental model, we examined herein the role of CD8+ T cells in the course of paracoccidioidomycosis. Treatment with anti-CD8 monoclonal antibodies caused a selective depletion of pulmonary and splenic CD8+ T cells in both mouse strains. The number of pulmonary CD4+ T cells and immunoglobulin-positive cells was independent of the number of CD8+ T cells. In susceptible mice, the loss of CD8+ T cells by in vivo treatment with anti-CD8 monoclonal antibodies impaired the clearance of yeasts from the lungs and increased the fungal dissemination to the liver and spleen. The same treatment in resistant mice increased fungal dissemination to extrapulmonary tissues but did not alter the pulmonary fungal load. Furthermore, CD8+ T-cell depletion did not modify delayed-type hypersensitivity reactions of A/Sn mice but increased these reactions in B10.A mice. The production of P. brasiliensis-specific antibodies by resistant and susceptible mice depleted of CD8+ T cells was similar to that of mice given control antibody. Histopathologically, depletion of CD8+ T cells did not disorganize the focal granulomatous lesions developed by both mouse strains. These results indicate that CD8+ T cells are necessary for optimal clearance of the fungus from tissues of mice infected with P. brasiliensisand demonstrate more prominent protective activity by those cells in the immune responses mounted by susceptible animals.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Daniel Rittirsch ◽  
Heinz Redl ◽  
Markus Huber-Lang

Multiorgan failure (MOF) represents the leading cause of death in patients with sepsis and systemic inflammatory response syndrome (SIRS) following severe trauma. The underlying immune response is highly complex and involves activation of the complement system as a crucial entity of innate immunity. Uncontrolled activation of the complement system during sepsis and SIRS with in excessive generation of complement activation products contributes to an ensuing dysfunction of various organ systems. In the present review, mechanisms of the inflammatory response in the development of MOF in sepsis and SIRS with particular focus on the complement system are discussed.


2021 ◽  
Author(s):  
Maria Chiara Trolese ◽  
Carlotta Scarpa ◽  
Valentina Melfi ◽  
Paola Fabbrizio ◽  
Francesca Sironi ◽  
...  

Abstract Background: Monocyte chemoattractant protein 1 (MCP1/CCL2) is one of the most powerful pro-inflammatory chemokines. However, its signalling is pivotal in driving axonal and muscle regeneration following injury. We previously showed that MCP1 is strongly upregulated in the nervous system of slow-progressing than fast-progressing SOD1G93A mice, which are characterised by a poor immune response that leads to a massive nerve and muscle degeneration.Methods: To assess the MCP1-mediated therapeutic role, we boosted the chemokine along the motor unit of the two SOD1G93A ALS models through a single intramuscular injection of a scAAV9 vector engineered with the Mcp1 gene (scAAV9_MCP1) at the pre-symptomatic disease stage.Results: Our observations revealed that slow-progressing SOD1G93A mice responded positively to the scAAV9_MCP1 injection anticipating the activation of the immune response, which sustained the pro-regenerative programme within nerves and skeletal muscles, eventually slackening the symptoms progression. Conversely, fast-progressing SOD1G93A mice exhibited an adverse response to the treatment, exacerbating the toxic inflammatory response in the periphery, resulting in worsened motor ability late in the disease.Intriguingly, our data suggested a novel pleiotropic role of MCP1 in the nervous system of SOD1G93A mice capable of promoting axon regeneration and modulating neuroinflammation, with the overall effect of preventing neurodegeneration.Conclusions: We provided direct evidence underlying the pivotal role of the immune response in promoting and governing skeletal muscle regeneration and thus the speed of ALS progression. The comparison study performed in fast- and slow-progressing SOD1G93A mice spotlights the nature and temporal activation of the inflammatory response as limiting factors to protect the peripheral compartment and interfere with the disease course tangibly. Altogether, these observations highlight the immune response as a key determinant for disease variability and proffer a reasonable explanation for the failure of systemic immunomodulatory treatments suggesting new potential strategies to hamper ALS progression.


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