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2.
Front Immunol ; 15: 1416275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139560

RESUMO

The intermediate filament vimentin is present in immune cells and is implicated in proinflammatory immune responses. Whether and how it supports antimicrobial activities of neutrophils are not well established. Here, we developed an immortalized neutrophil model to examine the requirement of vimentin. We demonstrate that vimentin restricts the production of proinflammatory cytokines and reactive oxygen species (ROS), but enhances phagocytosis and swarming. We observe that vimentin is dispensable for neutrophil extracellular trap (NET) formation, degranulation, and inflammasome activation. Moreover, gene expression analysis demonstrated that the presence of vimentin was associated with changes in expression of multiple genes required for mitochondrial function and ROS overproduction. Treatment of wild-type cells with rotenone, an inhibitor for complex I of the electron transport chain, increases the ROS levels. Likewise, treatment with mitoTEMPO, a SOD mimetic, rescues the ROS production in cells lacking vimentin. Together, these data show vimentin regulates neutrophil antimicrobial functions and alters ROS levels through regulation of mitochondrial activity.


Assuntos
Mitocôndrias , Neutrófilos , Espécies Reativas de Oxigênio , Vimentina , Espécies Reativas de Oxigênio/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Vimentina/metabolismo , Mitocôndrias/metabolismo , Animais , Camundongos , Inflamação/imunologia , Inflamação/metabolismo , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Fagocitose , Inflamassomos/metabolismo , Inflamassomos/imunologia , Citocinas/metabolismo , Humanos , Rotenona/farmacologia
3.
Front Immunol ; 15: 1403789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39156897

RESUMO

Streptococcus suis causes diseases in pigs and has emerged as a zoonotic agent. When infected, the host develops an exacerbated inflammation that can lead to septic shock and meningitis. Although neutrophils greatly infiltrate the lesions, their dynamics during S. suis infection remain poorly described. Moreover, very few studies reported on the production and role of a key factor in the regulation of neutrophils: the colony-stimulating granulocyte factor (G-CSF). In this study, we characterized the G-CSF-neutrophil axis in the pathogenesis of S. suis induced disease. Using a mouse model of S. suis infection, we first evaluated the recruitment of neutrophils and their activation profile by flow cytometry. We found that infection provokes a massive neutrophil recruitment from the bone marrow to the blood and spleen. In both compartments, neutrophils displayed multiple activation markers. In parallel, we observed high systemic levels of G-CSF, with a peak of production coinciding with that of neutrophil recruitment. We then neutralized the effects of G-CSF and highlighted its role in the release of neutrophils from the bone marrow to the blood. However, it did not affect bacteremia nor the cytokine storm induced by S. suis. In conclusion, systemic G-CSF induces the release of neutrophils from the bone marrow to the blood, but its role in inflammation or bacterial clearance seems to be compensated by unknown factors. A better understanding of the role of neutrophils and inflammatory mediators could lead to better strategies for controlling the infection caused by S. suis.


Assuntos
Fator Estimulador de Colônias de Granulócitos , Infiltração de Neutrófilos , Neutrófilos , Infecções Estreptocócicas , Streptococcus suis , Streptococcus suis/imunologia , Animais , Fator Estimulador de Colônias de Granulócitos/metabolismo , Infecções Estreptocócicas/imunologia , Camundongos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Infiltração de Neutrófilos/imunologia , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL
4.
Prostaglandins Leukot Essent Fatty Acids ; 202: 102636, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39159530

RESUMO

n3-PUFA impact health in several ways, including cardiovascular protection and anti-inflammatory effects, but the underlying mechanisms are not fully understood. In this exploratory study involving 31 healthy subjects, we aimed to investigate the effects of 12 weeks of fish-oil supplementation (1500 mg EPA+DHA/day) on the physical properties of multiple blood cell types. We used deformability cytometry (DC) for all cell types and Laser-assisted Optical Rotational Red Cell Analysis (Lorrca) to assess red blood cell (RBC) deformability. We also investigated the correlation between changes in the physical properties of blood cells and changes in the Omega-3 Index (O3I), defined as the relative content of EPA+DHA in RBCs. Following supplementation, the mean±SD O3I increased from 5.3 %±1.5 % to 8.3 %±1.4 % (p < 0.001). No significant changes in RBC properties were found by both techniques. However, by DC we observed a consistent pattern of physical changes in lymphocytes, neutrophils and monocytes. Among these were significant increases in metrics correlated with the cells' deformability resulting in less stiff cells. The results suggest that leukocytes become softer and have an increased ability to deform under induced short-term physical stress such as hydrodynamic force in the circulation. These changes could impact immune function since softer leukocytes can potentially circulate more easily and could facilitate a more rapid response to systemic inflammation or infection. In conclusion, fish-oil supplementation modulates some physical properties of leukocyte-subfractions, potentially enhancing their biological function. Further studies are warranted to explore the impact of n3-PUFA on blood cell biology, particularly in disease states associated with leukocyte dysregulation.

5.
bioRxiv ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39131367

RESUMO

Group B Streptococcus (GBS) is a Gram-positive pathobiont that commonly colonizes the gastrointestinal and lower female genital tracts but can cause sepsis and pneumonia in newborns and is a leading cause of neonatal meningitis. Despite the resulting disease severity, the pathogenesis of GBS is not completely understood, especially during the early phases of infection. To investigate GBS factors necessary for blood stream survival, we performed a transposon (Tn) mutant screen in our bacteremia infection model using a GBS mariner transposon mutant library previously developed by our group. We identified significantly underrepresented mutations in 628 genes that contribute to survival in the blood, including those encoding known virulence factors such as capsule, the ß-hemolysin, and inorganic metal ion transport systems. Most of the underrepresented genes have not been previously characterized or studied in GBS, including gloA and gloB, which are homologs for genes involved in methylglyoxal (MG) detoxification. MG is a byproduct of glycolysis and a highly reactive toxic aldehyde that is elevated in immune cells during infection. Here, we observed MG sensitivity across multiple GBS isolates and confirm that gloA contributes to MG tolerance and invasive GBS infection. We show specifically that gloA contributes to GBS survival in the presence of neutrophils and depleting neutrophils in mice abrogates the decreased survival and infection of the gloA mutant. The requirement of the glyoxalase pathway during GBS infection suggests that MG detoxification is important for bacterial survival during host-pathogen interactions.

6.
J Neuroimmune Pharmacol ; 19(1): 44, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152360

RESUMO

The systemic administration of interleukin-16 (IL-16, 3-30 ng/kg) induced thermal hyperalgesia in mice, that was prevented by the acute injection of an anti-CD4 antibody (1 µg/kg), the depletion of circulating white blood cells by cyclophosphamide or the specific reduction of circulating CD4+ cells provoked by a high dose of an anti-CD4 antibody (30 µg/mouse, 24 h before). IL-16-induced hyperalgesia was locally inhibited after intraplantar (i.pl.) administration of the non-selective cyclooxygenase (COX) inhibitor diclofenac, the COX-1 inhibitor SC-560, the COX-2 inhibitor celecoxib, the TRPV1 antagonist capsazepine or the TRPA1 antagonist HC030031, thus demonstrating that prostaglandins and TRP channels are involved in this effect. The i.pl. administration of low doses of IL-16 (0.1-1 ng) evoked local hyperalgesia suggesting the possibility that IL-16 could participate in hypernociception associated to local tissue injury. Accordingly, IL-16 concentration measured by ELISA was increased in paws acutely inflamed with carrageenan or chronically inflamed with complete Freund´s adjuvant (CFA). This augmentation was reduced after white cell depletion with cyclophosphamide or neutrophil depletion with an anti-Ly6G antibody. Immunofluorescence and flow cytometry experiments showed that the increased concentration of IL-16 levels found in acutely inflamed paws is mainly related to the infiltration of IL-16+ neutrophils, although a reduced number of IL-16+ lymphocytes was also detected in paws inflamed with CFA. Supporting the functional role of IL-16 in inflammatory hypernociception, the administration of an anti-IL-16 antibody dose-dependently reduced carrageenan- and CFA-induced thermal hyperalgesia and mechanical allodynia. The interest of IL-16 as a target to counteract inflammatory pain is suggested.


Assuntos
Hiperalgesia , Inflamação , Interleucina-16 , Animais , Camundongos , Hiperalgesia/tratamento farmacológico , Masculino , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente , Interleucina-16/metabolismo
7.
Immun Inflamm Dis ; 12(8): e1343, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39092750

RESUMO

The involvement of neutrophils in the lungs during the recovery phase of coronavirus disease 2019 (COVID-19) is not well defined mainly due to the limited accessibility of lung tissues from COVID-19 survivors. The lack of an appropriate small animal model has affected the development of effective therapeutic strategies. We here developed a long COVID mouse model to study changes in neutrophil phenotype and association with lung injury. Our data shows persistent neutrophil recruitment and neutrophil extracellular trap formation in the lungs for up to 30 days post-infection which correlates with lung fibrosis and inflammation.


Assuntos
COVID-19 , Modelos Animais de Doenças , Armadilhas Extracelulares , Pulmão , Neutrófilos , SARS-CoV-2 , Animais , Armadilhas Extracelulares/imunologia , COVID-19/imunologia , COVID-19/complicações , Camundongos , Neutrófilos/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Pulmão/patologia , Pulmão/imunologia , Pulmão/virologia , Lesão Pulmonar/imunologia , Lesão Pulmonar/virologia , Lesão Pulmonar/patologia , Lesão Pulmonar/etiologia , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Infiltração de Neutrófilos/imunologia , Humanos , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/patologia , Fibrose Pulmonar/etiologia
8.
ACS Nano ; 18(33): 22275-22297, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39105696

RESUMO

Nanomedicine has long pursued the goal of targeted delivery to specific organs and cell types but has yet to achieve this goal with the vast majority of targets. One rare example of success in this pursuit has been the 25+ years of studies targeting the lung endothelium using nanoparticles conjugated to antibodies against endothelial surface molecules. However, here we show that such "endothelial-targeted" nanocarriers also effectively target the lungs' numerous marginated neutrophils, which reside in the pulmonary capillaries and patrol for pathogens. We show that marginated neutrophils' uptake of many of these "endothelial-targeted" nanocarriers is on par with endothelial uptake. This generalizes across diverse nanomaterials and targeting moieties and was even found with physicochemical lung tropism (i.e., without targeting moieties). Further, we observed this in ex vivo human lungs and in vivo healthy mice, with an increase in marginated neutrophil uptake of nanoparticles caused by local or distant inflammation. These findings have implications for nanomedicine development for lung diseases. These data also suggest that marginated neutrophils, especially in the lungs, should be considered a major part of the reticuloendothelial system (RES), with a special role in clearing nanoparticles that adhere to the lumenal surfaces of blood vessels.


Assuntos
Pulmão , Nanopartículas , Neutrófilos , Animais , Neutrófilos/metabolismo , Neutrófilos/imunologia , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Nanopartículas/química , Sistema Fagocitário Mononuclear/metabolismo , Endotélio/metabolismo , Camundongos Endogâmicos C57BL , Nanomedicina
9.
Cell Commun Signal ; 22(1): 386, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090602

RESUMO

BACKGROUND: T-LAK cell-oriented protein kinase (TOPK) strongly promotes the malignant proliferation of cancer cells and is recognized as a promising biomarker of tumor progression. Psoriasis is a common inflammatory skin disease featured by excessive proliferation of keratinocytes. Although we have previously reported that topically inhibiting TOPK suppressed psoriatic manifestations in psoriasis-like model mice, the exact role of TOPK in psoriatic inflammation and the underlying mechanism remains elusive. METHODS: GEO datasets were analyzed to investigate the association of TOPK with psoriasis. Skin immunohistochemical (IHC) staining was performed to clarify the major cells expressing TOPK. TOPK conditional knockout (cko) mice were used to investigate the role of TOPK-specific deletion in IMQ-induced psoriasis-like dermatitis in mice. Flow cytometry was used to analyze the alteration of psoriasis-related immune cells in the lesional skin. Next, the M5-induced psoriasis cell model was used to identify the potential mechanism by RNA-seq, RT-RCR, and western blotting. Finally, the neutrophil-neutralizing antibody was used to confirm the relationship between TOPK and neutrophils in psoriasis-like dermatitis in mice. RESULTS: We found that TOPK levels were strongly associated with the progression of psoriasis. TOPK was predominantly increased in the epidermal keratinocytes of psoriatic lesions, and conditional knockout of TOPK in keratinocytes suppressed neutrophils infiltration and attenuated psoriatic inflammation. Neutrophils deletion by neutralizing antibody greatly diminished the suppressive effect of TOPK cko in psoriasis-like dermatitis in mice. In addition, topical application of TOPK inhibitor OTS514 effectively attenuated already-established psoriasis-like dermatitis in mice. Mechanismly, RNA-seq revealed that TOPK regulated the expression of some genes in the IL-17 signaling pathway, such as neutrophils chemokines CXCL1, CXCL2, and CXCL8. TOPK modulated the expression of neutrophils chemokines via activating transcription factors STAT3 and NF-κB p65 in keratinocytes, thereby promoting neutrophils infiltration and psoriasis progression. CONCLUSIONS: This study identified a crucial role of TOPK in psoriasis by regulating neutrophils infiltration, providing new insights into the pathogenesis of psoriasis.


Assuntos
Queratinócitos , Quinases de Proteína Quinase Ativadas por Mitógeno , Infiltração de Neutrófilos , Psoríase , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Progressão da Doença , Imiquimode , Queratinócitos/patologia , Queratinócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Neutrófilos/patologia , Psoríase/patologia , Psoríase/genética , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Regulação para Cima , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo
10.
Cureus ; 16(7): e64197, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39130833

RESUMO

AIM: The neutrophil-to-lymphocyte ratio (NLR) is commonly used as a prognostic indicator for microbiological and inflammatory conditions in clinical settings. However, the quotient to albumin levels, which is another nutritional and clinical predictor, may also have an interesting diagnostic and prognostic value. This study aimed to primarily investigate the predictive performances of the neutrophils to albumin and lymphocytes ratio (NALR) compared to the NLR in predicting poor outcomes during hospital admission, particularly the decomposition of respiratory, renal, liver, and circulatory systems, resulting in longer hospital stays or mortality. METHODS: An observational study was performed on a cohort of 270 hospitalised patients admitted to Rashid bin Al-Hussein Military Hospital during the period from October 2023 to early November 2023. The study specifically targeted adult patients (age >17 years) who had a minimum of 80% availability of their initial and follow-up data during admission. We dichotomised all eligible test patients into two groups: Group I, which represented better outcomes of interest, and Group II, which represented poorer outcomes of interest. Statistically, we conducted binary logistic, receiver operating, and sensitivity analyses to explore the predictive performances and indices for NALR and NLR. We also conducted chi-square and independent T analyses to uncover the distribution rates of the independent variables across Groups I and II. We considered a p-value of less than 0.05 as the level of significance. RESULTS: Out of a total sample size of 270, 82 patients (30.37%) were allocated to Group I, and 188 patients (69.63%) were allocated to Group II. Males outnumbered females in this study by 184 (68.1%) to 86 (31.9%). Patients in the study had an average age of 58.08±10.02 years. The average hospitalisation took 13.71±6.38 days, significantly longer in Group II compared to Group I (15.43±6.76 days vs. 9.77±2.69 days, p-value<0.05). We found that the area under the receiver operating characteristic (ROC) curves was estimated at [0.808±0.031 (0.748-0.868), p-value=0.000] and [0.667±0.034 (0.601-0.733), p-value=0.000] for NALR and NLR, respectively. The optimal operating thresholds for NALR and NLR were 1.5 and 5.37, with sensitivities and specificities of 86.7% versus 73.4% and 70.73% versus 70.73%, respectively. CONCLUSION: The proposed NALR showed superior predictive performance, sensitivity, and correlation compared to the parent NLR. Both tools can be used in clinical practice to prioritise clinical and pharmacotherapeutics for hospitalised patients based on unfavourable outcomes.

11.
Int Immunopharmacol ; 140: 112888, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39133956

RESUMO

Pancreatic cancer is characterized by an extremely poor prognosis and presents significant treatment challenges. Liver metastasis is the leading cause of death in patients with pancreatic cancer. Recent studies have highlighted the significant impact of neutrophils on tumor occurrence and progression, as well as their crucial role in the pancreatic cancer tumor microenvironment. Neutrophil infiltration plays a critical role in the progression and prognosis of pancreatic cancer. Neutrophils contribute to pancreatic cancer liver metastasis through various mechanisms, including angiogenesis, immune suppression, immune evasion, and epithelial-mesenchymal transition (EMT). Therefore, targeting neutrophils holds promise as an important therapeutic strategy for inhibiting pancreatic cancer liver metastasis. This article provides a summary of research findings on the involvement of neutrophils in pancreatic cancer liver metastasis and analyzes their potential as therapeutic targets. This research may provide new insights for the treatment of pancreatic cancer and improve the prognosis of patients with this disease.

12.
Adv Sci (Weinh) ; : e2400647, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119837

RESUMO

The development of acute respiratory distress syndrome (ARDS) in sepsis is associated with substantial morbidity and mortality. However, the molecular pathogenesis underlying sepsis-induced ARDS remains elusive. Neutrophil heterogeneity and dysfunction contribute to uncontrolled inflammation in patients with ARDS. A specific subset of neutrophils undergoing reverse transendothelial migration (rTEM), which is characterized by an activated phenotype, is implicated in the systemic dissemination of inflammation. Using single-cell RNA sequencing (scRNA-seq), it identified functionally activated neutrophils exhibiting the rTEM phenotype in the lung of a sepsis mouse model using cecal ligation and puncture. The prevalence of neutrophils with the rTEM phenotype is elevated in the blood of patients with sepsis-associated ARDS and is positively correlated with disease severity. Mechanically, scRNA-seq and proteomic analys revealed that inflamed endothelial cell (EC) released extracellular vesicles (EVs) enriched in karyopherin subunit beta-1 (KPNB1), promoting abluminal-to-luminal neutrophil rTEM. Additionally, EC-derived EVs are elevated and positively correlated with the proportion of rTEM neutrophils in clinical sepsis. Collectively, EC-derived EV is identified as a critical regulator of neutrophil rTEM, providing insights into the contribution of rTEM neutrophils to sepsis-associated lung injury.

13.
BMC Rheumatol ; 8(1): 34, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143483

RESUMO

BACKGROUND: to detect the role of procalcitonin, erythrocyte sedimentation rate to c-reactive protein (ESR/CRP) ratio, neutrophils-to-lymphocyte ratio (NLR), and platelets-to-lymphocyte ratio (PLR) in the diagnosis of infection in systemic lupus erythematosus (SLE) patients with fever, their diagnostic value to differentiate between infection and disease activity, and their correlation with disease activity. METHODS: Forty SLE patients and forty healthy control cases were included in the study. Disease activity was assessed by the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2 K), and quality of life was assessed by Lupus QoL. A bacterial infection was detected by clinical symptoms and positive culture results. Laboratory tests were done for all patients and controls: complete blood count (CBC), ESR, CRP, and procalcitonin (PCT). NLR, PLR, and ESR/CRP ratios were calculated. RESULTS: There was a statistically significant difference between infected SLE patients and non-infected SLE patients regarding PCT (p < 0.001), ESR (p = 0.002), CRP (p = 0.005), ESR/CRP ratio (0.002), and NLR (p = 0.023). PCT, ESR, CRP, and NLR were positively correlated with the presence of infection in SLE patients, while the ESR/CRP ratio was negatively correlated. There was no significant correlation with the SLEDAI-2 K score. Logistic regression analysis revealed that PCT was the best significant predictor of infection (OR 224.37, 95% CI 8.94-5631.35). PCT was a good predictor of infection, with a cut-off value of 0.90 ng/ml, which gave the best combination of sensitivity (84.62%) and specificity (85.71%). CONCLUSION: PCT, ESR/CRP ratio, and NLR provide good diagnostic markers for the diagnosis of infection and can distinguish between infection and disease flare in SLE patients with fever.

14.
BMC Med Genomics ; 17(1): 212, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143590

RESUMO

Non-coding RNA expression has shown to have cell type-specificity. The regulatory characteristics of these molecules are impacted by changes in their expression levels. We performed next-generation sequencing and examined small RNA-seq data obtained from 6 different types of blood cells separated by fluorescence-activated cell sorting of severe COVID-19 patients and healthy control donors. In addition to examining the behavior of piRNA in the blood cells of severe SARS-CoV-2 infected patients, our aim was to present a distinct piRNA differential expression portrait for each separate cell type. We observed that depending on the type of cell, different sorted control cells (erythrocytes, monocytes, lymphocytes, eosinophils, basophils, and neutrophils) have altering piRNA expression patterns. After analyzing the expression of piRNAs in each set of sorted cells from patients with severe COVID-19, we observed 3 significantly elevated piRNAs - piR-33,123, piR-34,765, piR-43,768 and 9 downregulated piRNAs in erythrocytes. In lymphocytes, all 19 piRNAs were upregulated. Monocytes were presented with a larger amount of statistically significant piRNA, 5 upregulated (piR-49039 piR-31623, piR-37213, piR-44721, piR-44720) and 35 downregulated. It has been previously shown that piR-31,623 has been associated with respiratory syncytial virus infection, and taking in account the major role of piRNA in transposon silencing, we presume that the differential expression patterns which we observed could be a signal of indirect antiviral activity or a specific antiviral cell state. Additionally, in lymphocytes, all 19 piRNAs were upregulated.


Assuntos
COVID-19 , Citometria de Fluxo , RNA Interferente Pequeno , SARS-CoV-2 , Humanos , COVID-19/genética , COVID-19/virologia , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/genética , SARS-CoV-2/genética , Masculino , Feminino , Pessoa de Meia-Idade , Monócitos/metabolismo , Adulto , Células Sanguíneas/metabolismo , RNA de Interação com Piwi
15.
Transl Stroke Res ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39168941

RESUMO

Specific inflammatory pathways are important in the development of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage. Understanding the specific pathways of inflammation may be critical for finding new treatments. Evidence is accumulating that innate inflammatory cells and proteins play a more important role than cells of the adaptive inflammatory system. In this work, we review the evidence from clinical and preclinical data regarding which cells of the immune system play a role in DCI with particular emphasis on the bone-marrow-derived cells monocytes and neutrophils and the brain parenchymal microglia. In addition, we will review the evidence that complement proteins, a non-cellular part of the innate immune system, play a role in the development of DCI.

17.
Int Immunopharmacol ; 141: 112963, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39159560

RESUMO

Fulminant viral hepatitis (FH) represents a significant clinical challenge, with its pathogenesis not yet fully elucidated. Heat shock protein (HSP)70, a molecular chaperone protein with a broad range of cytoprotective functions, is upregulated in response to stress. However, the role of HSP70 in FH remains to be investigated. Notably, HSP70 expression is upregulated in the livers of coronavirus-infected mice and patients. Therefore, we investigated the mechanistic role of HSP70 in coronavirus-associated FH pathogenesis. FH was induced in HSP70-deficient (HSP70 KO) mice or in WT mice treated with the HSP70 inhibitor VER155008 when infected with the mouse hepatitis virus strain A59 (MHV-A59). MHV-A59-infected HSP70 KO mice exhibited significantly reduced liver damage and mortality. This effect was attributed to decreased infiltration of monocyte-macrophages and neutrophils in the liver of HSP70 KO mice, resulting in lower levels of inflammatory cytokines such as IL-1ß, TNFα, and IL-6, and a reduced viral load. Moreover, treatment with the HSP70 inhibitor VER155008 protected mice from MHV-A59-induced liver damage and FH mortality. In summary, HSP70 promotes coronavirus-induced FH pathogenesis by enhancing the infiltration of monocyte-macrophages and neutrophils and promoting the secretion of inflammatory cytokines. Therefore, HSP70 is a potential therapeutic target in viral FH intervention.

18.
J Leukoc Biol ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107254

RESUMO

During recovery from septic shock, circulating mitochondrial N-formyl peptides (mtFPs) predispose to secondary infection by occupying formyl peptide receptor 1 (FPR1) on the neutrophil (polymorphonuclear leukocyte, PMN) membrane, suppressing cytosolic calcium ([Ca2+]i)-dependent responses to secondarily encountered bacteria. However, no study has yet investigated therapeutic clearance of circulating mtFPs in clinical settings. Thus, we studied how to remove mtFPs from septic-shock plasma and whether such removal could preserve cell-surface FPR1 and restore sepsis-induced PMN dysfunction by normalizing [Ca2+]i flux. In in vitro model systems, mtFP removal rescued PMN FPR1-mediated [Ca2+]i flux and chemotaxis that had been suppressed by prior mtFP exposure. However, PMN functional recovery occurred in a stepwise fashion over 30 - 90 minutes. Intracellular Ca2+-calmodulin appears to contribute to this delay. In ex vivo model systems using blood samples obtained from patients with septic shock, anti-mtFP antibodies alone failed to eliminate mtFPs from septic-shock plasma or inhibit mtFP activity. We therefore created a beads-based anti-mtFP antibody cocktail (bb-AMfpA) by combining protein A/sepharose with antibodies specific for the most potent human mtFP chemoattractants. The bb-AMfpA treatment successfully removed those active mtFPs from septic-shock plasma. Furthermore, the bb-AMfpA treatment significantly restored chemotactic and bactericidal dysfunction of PMNs obtained from patients with septic shock who developed secondary infections. By clearing circulating mtFPs, the immobilized anti-mtFP antibody therapy prevented mtFP interactions with surface FPR1, thereby restoring [Ca2+]i-dependent PMN antimicrobial function in clinical septic-shock environments. This approach may help prevent the development of secondary, nosocomial infections in patients recovering from septic shock.

19.
Artigo em Inglês | MEDLINE | ID: mdl-39107892

RESUMO

OBJECTIVE: Pathogenesis of antiphospholipid syndrome (APS) remains poorly elucidated. We aimed to evaluate for the first time, kidney transcriptome profiles in primary APS vs systemic lupus erythematosus (SLE) and control subjects. METHODS: We performed RNA-sequencing on archival formalin-fixed paraffin-embedded kidney biopsies from APS (n = 4) SLE (n = 5), and control (n = 3) individuals, differential gene expression analysis (DGEA), and enrichment analysis using gene ontology (GO), and CORUM, KEGG and Reactome pathway databases. RESULTS: Two-dimensional projection showed a distinct gene profile in primary APS vs control kidneys samples, but similar to SLE. DGEA in APS vs controls returned 276 upregulated and 217 downregulated genes, while the comparison between APS and SLE identified 75 upregulated and 111 downregulated genes. In 276 upregulated genes, enriched GO terms were (innate) immune response, inflammatory response, leucocyte and lymphocyte activation, cytokine production and T cell activation. CORUM and KEGG revealed complement-related genes (C3, C4A, C4B). Expression levels showed logFC values of 2.25 (p= 1.58e-05) for C3, 2.17 (p= 2.69e-06) for C4A, and 2.135 (p= 3.7e-06) for C4B in APS vs controls, without differences between APS and SLE. Interferon (IFN) alpha/beta signalling was revealed by Reactome. Expression levels of nine IFN-regulated genes found upregulated in APS vs control kidneys (p-values ≤ 0.001 for all). Examining neutrophil-extracellular traps (NETs)-related gene expression, 13 of 15 upregulated NETs-related genes exhibited higher expression in APS vs controls but not vs SLE. CONCLUSION: Complement, interferon and NETs-related genes are highly expressed in APS kidney tissues, similarly to SLE, pointing out the role of innate immunity in APS nephropathy pathogenesis and potential treatment targets.

20.
Biomed Pharmacother ; 178: 117269, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39137654

RESUMO

Excessive neutrophil infiltration into the tumor microenvironment (TME) is an important factor that contributes to tumor overgrowth and limited immunotherapy efficacy. Neutrophils activate various receptors involved in tumor progression, while suppressing the infiltration and activity of cytotoxic T cells and creating optimal conditions for tumor growth. Therefore, the appropriate control of neutrophil infiltration is an effective strategy for tumor treatment. In the present study, 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) inhibited tumor overgrowth by suppressing excessive neutrophil infiltration, resulting in >74.97 % reduction in tumor size in a Lewis lung carcinoma (LLC-1) mouse model. All subjects in the positive control group died during the 90-day survival period, whereas only four subjects in the PLAG treatment group survived. PLAG had a significantly higher tumor growth inhibitory effect and survival rate than other neutrophil infiltration-targeting inhibitors (e.g., Navarixin, lymphocyte antigen 6 complex locus G6D antibody [aLy6G]). The ability of PLAG to regulate neutrophil infiltration and inhibit tumor growth depends on thioredoxin-interacting protein (TXNIP). In tumors lacking TXNIP expression, PLAG failed to control neutrophil infiltration and infiltration-related factor release, and the inhibitory effect of PLAG on tumor growth was reduced. PLAG-mediated inhibition of neutrophil infiltration enhances the efficacy of immune checkpoint inhibitors (ICIs), increasing the antitumor efficacy and survival rate by 30 %. In conclusion, PLAG could be a novel alternative to anti-tumor drugs that effectively targets excessive neutrophil infiltration into cancer tissues.

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