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Atre R, Sharma R, Obukhov AG, Saqib U, Umar S, Darwhekar GN, Baig MS. An improved mouse model of sepsis based on intraperitoneal injections of the enriched culture of cecum slurry. Life Sci 2024; 345:122584. [PMID: 38527668 DOI: 10.1016/j.lfs.2024.122584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/07/2024] [Accepted: 03/18/2024] [Indexed: 03/27/2024]
Abstract
AIM Sepsis is a life-threatening clinical syndrome comprising multiorgan dysfunctions caused by a disproportionate body immune response. There are several animal sepsis models which are based on cecum ligation, cecal puncture, and cecum slurry injection. The major limitation of all current sepsis models is the high variability owing to the variable degree of ligation, puncture and inconsistent microbial composition used for sepsis initiation. The primary objective of this work is to demonstrate the feasibility of a standardized method for sepsis development. MATERIALS AND METHODS The cecal slurry bacterial culture was developed and preserved in glycerol stocks. Antibiotics aztreonam and vancomycin were used for generating several defined, enriched cecal slurry bacterial cultures. Mice survival was assessed until 48 hrs post injection, and the tissue samples were collected after 10 hrs from sepsis initiation. KEY FINDINGS The results indicate that increasing polymicrobial load resulted in lower survival rates and was associated with the higher number of infiltrating immune cells and necrosis. H&E (haematoxylin & eosin) staining & serum markers revealed that septic mice exhibited increased inflammation and significant damage to the liver and kidneys. The defined Gram-negative and Gram-positive specific cecal slurry bacterial cultures were developed and their efficiency in inducing sepsis was characterized. SIGNIFICANCE Enriched cecal slurry bacterial cultures can be stored in glycerol stocks at -80 °C. This has an ethical advantage of avoiding unnecessary animal euthanasia for each experiment and provides a standardization capability of sepsis development.
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Affiliation(s)
- Rajat Atre
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, MP 453552, India
| | - Rahul Sharma
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, MP 453552, India
| | - Alexander G Obukhov
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Uzma Saqib
- School of Life Sciences, Devi Ahilya Vishwavidyalaya, Vigyan Bhawan, Indore, MP 452 001, India
| | - Sadiq Umar
- Department of Oral Biology, College of Dentistry, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Gajanan N Darwhekar
- Acropolis Institute of Pharmaceutical Education and Research (AIPER), Indore, MP 453771, India
| | - Mirza S Baig
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, MP 453552, India.
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Chadda KR, Puthucheary Z. Persistent inflammation, immunosuppression, and catabolism syndrome (PICS): a review of definitions, potential therapies, and research priorities. Br J Anaesth 2024; 132:507-518. [PMID: 38177003 PMCID: PMC10870139 DOI: 10.1016/j.bja.2023.11.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 11/17/2023] [Accepted: 11/19/2023] [Indexed: 01/06/2024] Open
Abstract
Persistent Inflammation, Immunosuppression, and Catabolism Syndrome (PICS) is a clinical endotype of chronic critical illness. PICS consists of a self-perpetuating cycle of ongoing organ dysfunction, inflammation, and catabolism resulting in sarcopenia, immunosuppression leading to recurrent infections, metabolic derangements, and changes in bone marrow function. There is heterogeneity regarding the definition of PICS. Currently, there are no licensed treatments specifically for PICS. However, findings can be extrapolated from studies in other conditions with similar features to repurpose drugs, and in animal models. Drugs that can restore immune homeostasis by stimulating lymphocyte production could have potential efficacy. Another treatment could be modifying myeloid-derived suppressor cell (MDSC) activation after day 14 when they are immunosuppressive. Drugs such as interleukin (IL)-1 and IL-6 receptor antagonists might reduce persistent inflammation, although they need to be given at specific time points to avoid adverse effects. Antioxidants could treat the oxidative stress caused by mitochondrial dysfunction in PICS. Possible anti-catabolic agents include testosterone, oxandrolone, IGF-1 (insulin-like growth factor-1), bortezomib, and MURF1 (muscle RING-finger protein-1) inhibitors. Nutritional support strategies that could slow PICS progression include ketogenic feeding and probiotics. The field would benefit from a consensus definition of PICS using biologically based cut-off values. Future research should focus on expanding knowledge on underlying pathophysiological mechanisms of PICS to identify and validate other potential endotypes of chronic critical illness and subsequent treatable traits. There is unlikely to be a universal treatment for PICS, and a multimodal, timely, and personalised therapeutic strategy will be needed to improve outcomes for this growing cohort of patients.
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Affiliation(s)
- Karan R Chadda
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, London, UK; Homerton College, University of Cambridge, Cambridge, UK; Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.
| | - Zudin Puthucheary
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, London, UK; Adult Critical Care Unit, Royal London Hospital, London, UK
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3
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Vaz MSM, de Almeida de Souza GH, Dos Santos Radai JA, Fraga TL, de Oliveira GG, Wender H, da Silva KE, Simionatto S. Antimicrobial activity of cinnamaldehyde against multidrug-resistant Klebsiella pneumoniae: an in vitro and in vivo study. Braz J Microbiol 2023; 54:1655-1664. [PMID: 37392293 PMCID: PMC10485196 DOI: 10.1007/s42770-023-01040-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/10/2023] [Indexed: 07/03/2023] Open
Abstract
The emergence and spread of multidrug-resistant (MDR) Klebsiella pneumoniae strains have increased worldwide, posing a significant health threat by limiting the therapeutic options. This study aimed to investigate the antimicrobial potential of cinnamaldehyde against MDR-K. pneumoniae strains in vitro and in vivo assays. The presence of resistant genes in MDR- K. pneumoniae strains were evaluated by Polymerase Chain Reaction (PCR) and DNA sequencing. Carbapenem-resistant K. pneumoniae strains show the blaKPC-2 gene, while polymyxin-resistant K. pneumoniae presented blaKPC-2 and alterations in the mgrB gene. Cinnamaldehyde exhibited an inhibitory effect against all MDR- K. pneumoniae evaluated. An infected mice model was used to determine the in vivo effects against two K. pneumoniae strains, one carbapenem-resistant and another polymyxin-resistant. After 24 h of cinnamaldehyde treatment, the bacterial load in blood and peritoneal fluids decreased. Cinnamaldehyde showed potential effectiveness as an antibacterial agent by inhibiting the growth of MDR-K. pneumoniae strains.
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Affiliation(s)
- Marcia Soares Mattos Vaz
- Laboratório de Pesquisa Em Ciências da Saúde, Universidade Federal da Grande Dourados-UFGD, Cidade Universitária, Itahum, Km 12, Dourados, Mato Grosso Do Sul, CEP: 79804970, Brazil
| | - Gleyce Hellen de Almeida de Souza
- Laboratório de Pesquisa Em Ciências da Saúde, Universidade Federal da Grande Dourados-UFGD, Cidade Universitária, Itahum, Km 12, Dourados, Mato Grosso Do Sul, CEP: 79804970, Brazil
| | - Joyce Alencar Dos Santos Radai
- Laboratório de Pesquisa Em Ciências da Saúde, Universidade Federal da Grande Dourados-UFGD, Cidade Universitária, Itahum, Km 12, Dourados, Mato Grosso Do Sul, CEP: 79804970, Brazil
| | - Thiago Leite Fraga
- Centro Universitário da Grande Dourados-UNIGRAN, Dourados, Mato Grosso Do Sul, Brazil
| | | | - Heberton Wender
- Grupo de Pesquisa Em Nano E Fótons, Instituto de Física, Universidade Federal de Mato Grosso Do Sul, Campo Grande, Brazil
| | - Kesia Esther da Silva
- Laboratório de Pesquisa Em Ciências da Saúde, Universidade Federal da Grande Dourados-UFGD, Cidade Universitária, Itahum, Km 12, Dourados, Mato Grosso Do Sul, CEP: 79804970, Brazil
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, CA, 94304, USA
| | - Simone Simionatto
- Laboratório de Pesquisa Em Ciências da Saúde, Universidade Federal da Grande Dourados-UFGD, Cidade Universitária, Itahum, Km 12, Dourados, Mato Grosso Do Sul, CEP: 79804970, Brazil.
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Cai L, Rodgers E, Schoenmann N, Raju RP. Advances in Rodent Experimental Models of Sepsis. Int J Mol Sci 2023; 24:9578. [PMID: 37298529 PMCID: PMC10253762 DOI: 10.3390/ijms24119578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/09/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
In the development of therapeutic strategies for human diseases, preclinical experimental models have a key role. However, the preclinical immunomodulatory therapies developed using rodent sepsis were not successful in human clinical trials. Sepsis is characterized by a dysregulated inflammation and redox imbalance triggered by infection. Human sepsis is simulated in experimental models using methods that trigger inflammation or infection in the host animals, most often mice or rats. It remains unknown whether the characteristics of the host species, the methods used to induce sepsis, or the molecular processes focused upon need to be revisited in the development of treatment methods that will succeed in human clinical trials. Our goal in this review is to provide a survey of existing experimental models of sepsis, including the use of humanized mice and dirty mice, and to show how these models reflect the clinical course of sepsis. We will discuss the strengths and limitations of these models and present recent advances in this subject area. We maintain that rodent models continue to have an irreplaceable role in studies toward discovering treatment methods for human sepsis.
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Affiliation(s)
- Lun Cai
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Elizabeth Rodgers
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Nick Schoenmann
- Department of Emergency Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Raghavan Pillai Raju
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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MicroRNA Profiles in Intestinal Epithelial Cells in a Mouse Model of Sepsis. Cells 2023; 12:cells12050726. [PMID: 36899862 PMCID: PMC10001189 DOI: 10.3390/cells12050726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/22/2023] [Accepted: 02/22/2023] [Indexed: 03/03/2023] Open
Abstract
Sepsis is a systemic inflammatory disorder that leads to the dysfunction of multiple organs. In the intestine, the deregulation of the epithelial barrier contributes to the development of sepsis by triggering continuous exposure to harmful factors. However, sepsis-induced epigenetic changes in gene-regulation networks within intestinal epithelial cells (IECs) remain unexplored. In this study, we analyzed the expression profile of microRNAs (miRNAs) in IECs isolated from a mouse model of sepsis generated via cecal slurry injection. Among 239 miRNAs, 14 miRNAs were upregulated, and 9 miRNAs were downregulated in the IECs by sepsis. Upregulated miRNAs in IECs from septic mice, particularly miR-149-5p, miR-466q, miR-495, and miR-511-3p, were seen to exhibit complex and global effects on gene regulation networks. Interestingly, miR-511-3p has emerged as a diagnostic marker in this sepsis model due to its increase in blood in addition to IECs. As expected, mRNAs in the IECs were remarkably altered by sepsis; specifically, 2248 mRNAs were decreased, while 612 mRNAs were increased. This quantitative bias may be possibly derived, at least partly, from the direct effects of the sepsis-increased miRNAs on the comprehensive expression of mRNAs. Thus, current in silico data indicate that there are dynamic regulatory responses of miRNAs to sepsis in IECs. In addition, the miRNAs that were increased with sepsis had enriched downstream pathways including Wnt signaling, which is associated with wound healing, and FGF/FGFR signaling, which has been linked to chronic inflammation and fibrosis. These modifications in miRNA networks in IECs may lead to both pro- and anti-inflammatory effects in sepsis. The four miRNAs discovered above were shown to putatively target LOX, PTCH1, COL22A1, FOXO1, or HMGA2, via in silico analysis, which were associated with Wnt or inflammatory pathways and selected for further study. The expressions of these target genes were downregulated in sepsis IECs, possibly through posttranscriptional modifications of these miRNAs. Taken together, our study suggests that IECs display a distinctive miRNA profile which is capable of comprehensively and functionally reshaping the IEC-specific mRNA landscape in a sepsis model.
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6
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Wang N, Lu Y, Zheng J, Liu X. Of mice and men: Laboratory murine models for recapitulating the immunosuppression of human sepsis. Front Immunol 2022; 13:956448. [PMID: 35990662 PMCID: PMC9388785 DOI: 10.3389/fimmu.2022.956448] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/12/2022] [Indexed: 11/13/2022] Open
Abstract
Prolonged immunosuppression is increasingly recognized as the major cause of late phase and long-term mortality in sepsis. Numerous murine models with different paradigms, such as lipopolysaccharide injection, bacterial inoculation, and barrier disruption, have been used to explore the pathogenesis of immunosuppression in sepsis or to test the efficacy of potential therapeutic agents. Nonetheless, the reproducibility and translational value of such models are often questioned, owing to a highly heterogeneric, complex, and dynamic nature of immunopathology in human sepsis, which cannot be consistently and stably recapitulated in mice. Despite of the inherent discrepancies that exist between mice and humans, we can increase the feasibility of murine models by minimizing inconsistency and increasing their clinical relevance. In this mini review, we summarize the current knowledge of murine models that are most commonly used to investigate sepsis-induced immunopathology, highlighting their strengths and limitations in mimicking the dysregulated immune response encountered in human sepsis. We also propose potential directions for refining murine sepsis models, such as reducing experimental inconsistencies, increasing the clinical relevance, and enhancing immunological similarities between mice and humans; such modifications may optimize the value of murine models in meeting research and translational demands when applied in studies of sepsis-induced immunosuppression.
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Affiliation(s)
- Ning Wang
- West China Biopharm Research Institute, West China Hospital, Sichuan University, Chengdu, China
| | - Yongling Lu
- Medical Research Center, Southwest Hospital, Army Military Medical University, Chongqing, China
| | - Jiang Zheng
- Medical Research Center, Southwest Hospital, Army Military Medical University, Chongqing, China
- *Correspondence: Jiang Zheng, ; Xin Liu,
| | - Xin Liu
- Medical Research Center, Southwest Hospital, Army Military Medical University, Chongqing, China
- *Correspondence: Jiang Zheng, ; Xin Liu,
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7
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Voelker MT, Hechaichi N, Ndongson-Dongmo B, Lemm J, Heller R, Bauer R, Conway EM, Theilmeier G, Stehr SN. Role of the lectin-like domain of thrombomodulin in septic cardiomyopathy. Life Sci 2022; 306:120830. [PMID: 35872006 DOI: 10.1016/j.lfs.2022.120830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/10/2022] [Accepted: 07/18/2022] [Indexed: 11/25/2022]
Abstract
AIMS Septic cardiomyopathy is a severe complication of sepsis and septic shock. This study aimed to evaluate the role of thrombomodulin and its lectin-like domain (LLD-TM) in the development of septic cardiomyopathy and the link between LLD-TM, HMGB-1, and toll-like receptors 2/4 (TLR 2/4) to intracellular mechanisms resulting in reduced cardiac function. MATERIALS AND METHODS Sepsis was induced using a polymicrobial peritoneal infection model in wildtype and mice lacking the lectin-like domain of thrombomodulin (TMLeD/LeD), and severity of disease and cardiac function was compared. Cell cultures of cardiomyocytes were prepared from hearts harvested from wildtype and TMLeD/LeD mice. Cultures of neonatal cardiomyocytes were transfected with complete human thrombomodulin or human thrombomodulin deficient of LLD-TM and when TLR-2 and/or TLR-4 were blocked. All cultures were challenged with inflammatory stimuli. KEY FINDINGS Lack of the LLD-TM results in a significant increase in severity of disease, decreased survival and impaired cardiac function in septic mice. In vivo and in vitro analyses of cardiomyocytes displayed high levels of inflammatory cytokines causing cardio-depression. In vitro results showed a strong correlation between elevated HMGB-1 levels and elevated troponin-1 levels. No connection was found between HMGB-1 and TLR-2 and/or -4 signalling pathways. Phospholamban mediated dysregulation of calcium homeostasis resulted in a general impairment after sepsis induction, but showed no connection to LLD-TM. SIGNIFICANCE Lack of LLD-TM results in an increase in general severity of disease, decreased survival and impaired cardiac function in sepsis. TLR-2 and TLR 4 do not participate as mediating factors in the development of septic cardiomyopathy.
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Affiliation(s)
- Maria Theresa Voelker
- Department of Anaesthesiology and Critical Care Medicine, University Hospital Leipzig, Germany.
| | - Nadine Hechaichi
- Center for Sepsis Control and Care, University Hospital Jena, Germany
| | - Bernadin Ndongson-Dongmo
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Jana Lemm
- Center for Sepsis Control and Care, University Hospital Jena, Germany
| | - Regine Heller
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Reinhardt Bauer
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Edward M Conway
- UBC Centre for Blood Research, Faculty of Medicine, Division of Haematology, Life Sciences Institute, Vancouver, British Columbia, Canada
| | - Gregor Theilmeier
- Division of Perioperative Inflammation and Infection, Faculty of Medicine and Health Sciences, Oldenburg, Germany
| | - Sebastian N Stehr
- Department of Anaesthesiology and Critical Care Medicine, University Hospital Leipzig, Germany; Center for Sepsis Control and Care, University Hospital Jena, Germany
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Walker SLM, Muthoo C, Sanchez J, Del Arroyo AG, Ackland GL. Sex-specific differences in cardiac function, inflammation and injury during early polymicrobial sepsis. Intensive Care Med Exp 2022; 10:27. [PMID: 35723764 PMCID: PMC9209626 DOI: 10.1186/s40635-022-00454-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 05/16/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sex differences in sepsis are underexplored and incompletely understood. Cardiac function in early sepsis is pivotal in determining survival; hyperdynamic left ventricular ejection fraction is associated with higher mortality. Female sex may be cardioprotective, but variable experimental findings have not controlled for hypovolaemia. Sex-specific local cardiac versus peripheral inflammation in causing cardiovascular dysfunction also remain unclear. We therefore examined whether there are sex-specific differences in cardiac function in early sepsis, controlling for volaemic status and sex-specific differences in the peripheral inflammatory response initiated by tumour necrosis factor (TNFα). METHODS We used an experimental polymicrobial sepsis (faecal slurry) model titrated to minimise hypovolaemia as a confounding factor. We quantified cardiac function (transthoracic cardiac echocardiography) 1 week before, and 18 h after, sepsis. Cardiac injury (troponin I), inflammation and immune cell infiltration (flow cytometry) were quantified in naïve and septic female and male mice 18 h after sepsis. To evaluate the sex-specific influence of TNFα derived from peripheral leukocytes, we repeated the experiments in iRHOM2-/- mice that are unable to shed TNFα exclusively from circulating leucocytes. RESULTS Serum troponin I increased to 1.39 ± 0.38 ng mL-1 (from undetectable levels in controls) 18 h after onset of normovolaemic sepsis to a similar extent in both sexes. Stroke volume in male mice increased by 8 µL [(3-13); p = 0.004], compared to individualised pre-sepsis values. By contrast, stroke volume remained at baseline levels in females [mean difference: 4 µL (- 1 to 9)]. Messenger RNA levels of markers for cardiac injury/inflammation after sepsis (real-time polymerase-chain reaction) were elevated in male wild-type mice compared to female wild types (n = 10/sex), with higher cardiac mRNA levels of atrial natriuretic peptide, inflammation (TNFα) and oxidative stress (superoxide dismutase-1), although serum troponin I values were similarly elevated. Flow cytometry analysis of cardiac tissue showed doubling of CD4 + leukocyte infiltration in male mice. Sex-specific cardiac physiologic differences were similar in iRHOM2-/- mice that are unable to shed TNFα exclusively from leucocytes. CONCLUSIONS In early normovolaemic polymicrobial sepsis, a relative hyperdynamic response develops in male mice. Myocardial stress/injury after early sepsis is limited in females, with less cardiac infiltration of CD4 + leukocytes but independent of shedding of TNFα from peripheral circulating leukocytes.
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Affiliation(s)
- Sophie L M Walker
- Translational Medicine and Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Chand Muthoo
- Translational Medicine and Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Jenifer Sanchez
- Translational Medicine and Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Ana Gutierrez Del Arroyo
- Translational Medicine and Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Gareth L Ackland
- Translational Medicine and Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK.
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Proprotein Convertase Subtilisin/Kexin Type 9 Loss-of-Function Is Detrimental to the Juvenile Host With Septic Shock. Crit Care Med 2021; 48:1513-1520. [PMID: 32769621 DOI: 10.1097/ccm.0000000000004487] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Proprotein convertase subtilisin/kexin type 9 is a central regulator of lipid metabolism and has been implicated in regulating the host response to sepsis. Proprotein convertase subtilisin/kexin type 9 loss-of-function is associated with improved sepsis outcomes in the adult host through increased hepatic bacterial clearance. Thus, there is interest in leveraging proprotein convertase subtilisin/kexin type 9 inhibitors as a therapeutic strategy in adults with sepsis. We sought to validate this association in children with septic shock and in a juvenile murine model of sepsis. DESIGN Prospectively enrolled cohort of children with septic shock; experimental mice. SETTING Seventeen participating institutions; research laboratory. PATIENTS AND SUBJECTS Five-hundred twenty-two children with septic shock; juvenile (14 d old) and adult (10-14 wk) mice with constitutive proprotein convertase subtilisin/kexin type 9 null and wildtype control mice (C57BL/6). INTERVENTIONS Proprotein convertase subtilisin/kexin type 9 single-nucleotide polymorphisms, serum proprotein convertase subtilisin/kexin type 9, and lipid profiles in patients. Cecal slurry murine model of sepsis; survival studies in juvenile and adult mice, assessment of lipoprotein fractions, bacterial burden, and inflammation in juvenile mice. MEASUREMENTS AND MAIN RESULTS PCSK9 loss-of-function genetic variants were independently associated with increased odds of complicated course and mortality in children with septic shock. PCSK9, low-density lipoprotein, and high-density lipoprotein concentrations were lower among patients with complicated course relative to those without. PCSK9 concentrations negatively correlated with proinflammatory cytokine interleukin-8. Proprotein convertase subtilisin/kexin type 9 loss-of-function decreased survival in juvenile mice, but increased survival in adult mice with sepsis. PCSK9 loss-of-function resulted in low lipoproteins and decreased hepatic bacterial burden in juvenile mice. CONCLUSIONS In contrast to the adult host, proprotein convertase subtilisin/kexin type 9 loss-of-function is detrimental to the juvenile host with septic shock. PCSK9 loss-of-function, in the context of low lipoproteins, may result in reduced hepatic bacterial clearance in the juvenile host with septic shock. Our data indicate that children should be excluded in sepsis clinical trials involving proprotein convertase subtilisin/kexin type 9 inhibitors.
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Fallon EA, Chung CS, Heffernan DS, Chen Y, De Paepe ME, Ayala A. Survival and Pulmonary Injury After Neonatal Sepsis: PD1/PDL1's Contributions to Mouse and Human Immunopathology. Front Immunol 2021; 12:634529. [PMID: 33746973 PMCID: PMC7965961 DOI: 10.3389/fimmu.2021.634529] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 02/08/2021] [Indexed: 12/14/2022] Open
Abstract
Morbidity and mortality associated with neonatal sepsis remains a healthcare crisis. PD1-/- neonatal mice endured experimental sepsis, in the form of cecal slurry (CS), and showed improved rates of survival compared to wildtype (WT) counterparts. End-organ injury, particularly of the lung, contributes to the devastation set forth by neonatal sepsis. PDL1-/- neonatal mice, in contrast to PD1-/- neonatal mice did not have a significant improvement in survival after CS. Because of this, we focused subsequent studies on the impact of PD1 gene deficiency on lung injury. Here, we observed that at 24 h post-CS (but not at 4 or 12 h) there was a marked increase in pulmonary edema (PE), neutrophil influx, myeloperoxidase (MPO) levels, and cytokine expression sham (Sh) WT mice. Regarding pulmonary endothelial cell (EC) adhesion molecule expression, we observed that Zona occludens-1 (ZO-1) within the cell shifted from a membranous location to a peri-nuclear location after CS in WT murine cultured ECs at 24hrs, but remained membranous among PD1-/- lungs. To expand the scope of this inquiry, we investigated human neonatal lung tissue. We observed that the lungs of human newborns exposed to intrauterine infection had significantly higher numbers of PD1+ cells compared to specimens who died from non-infectious causes. Together, these data suggest that PD1/PDL1, a pathway typically thought to govern adaptive immune processes in adult animals, can modulate the largely innate neonatal pulmonary immune response to experimental septic insult. The potential future significance of this area of study includes that PD1/PDL1 checkpoint proteins may be viable therapeutic targets in the septic neonate.
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Affiliation(s)
- Eleanor A. Fallon
- Division of Surgical Research, Department of Surgery, Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, United States
| | - Chun-Shiang Chung
- Division of Surgical Research, Department of Surgery, Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, United States
| | - Daithi S. Heffernan
- Division of Surgical Research, Department of Surgery, Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, United States
- Department of Surgery, Providence Veterans Affairs Medical Center, Providence, RI, United States
| | - Yaping Chen
- Division of Surgical Research, Department of Surgery, Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, United States
| | - Monique E. De Paepe
- Department of Pathology, Women & Infants Hospital and Alpert Medical School of Brown University, Providence, RI, United States
| | - Alfred Ayala
- Division of Surgical Research, Department of Surgery, Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, United States
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11
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Fenner BP, Darden DB, Kelly LS, Rincon J, Brakenridge SC, Larson SD, Moore FA, Efron PA, Moldawer LL. Immunological Endotyping of Chronic Critical Illness After Severe Sepsis. Front Med (Lausanne) 2021; 7:616694. [PMID: 33659259 PMCID: PMC7917137 DOI: 10.3389/fmed.2020.616694] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/14/2020] [Indexed: 12/15/2022] Open
Abstract
Improved management of severe sepsis has been one of the major health care accomplishments of the last two decades. Due to enhanced recognition and improved management of severe sepsis, in-hospital mortality has been reduced by up to 40%. With that good news, a new syndrome has unfortunately replaced in-hospital multi-organ failure and death. This syndrome of chronic critical illness (CCI) includes sepsis patients who survive the early "cytokine or genomic storm," but fail to fully recover, and progress into a persistent state of manageable organ injury requiring prolonged intensive care. These patients are commonly discharged to long-term care facilities where sepsis recidivism is high. As many as 33% of sepsis survivors develop CCI. CCI is the result, at least in part, of a maladaptive host response to chronic pattern-recognition receptor (PRR)-mediated processes. This maladaptive response results in dysregulated myelopoiesis, chronic inflammation, T-cell atrophy, T-cell exhaustion, and the expansion of suppressor cell functions. We have defined this panoply of host responses as a persistent inflammatory, immune suppressive and protein catabolic syndrome (PICS). Why is this important? We propose that PICS in survivors of critical illness is its own common, unique immunological endotype driven by the constant release of organ injury-associated, endogenous alarmins, and microbial products from secondary infections. While this syndrome can develop as a result of a diverse set of pathologies, it represents a shared outcome with a unique underlying pathobiological mechanism. Despite being a common outcome, there are no therapeutic interventions other than supportive therapies for this common disorder. Only through an improved understanding of the immunological endotype of PICS can rational therapeutic interventions be designed.
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Affiliation(s)
- Brittany P Fenner
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - D B Darden
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Lauren S Kelly
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Jaimar Rincon
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Scott C Brakenridge
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Shawn D Larson
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Frederick A Moore
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Philip A Efron
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
| | - Lyle L Moldawer
- Department of Surgery, Sepsis and Critical Illness Research Center, University of Florida College of Medicine, Gainesville, FL, United States
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12
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Lehmann C, Aali M, Zhou J, Holbein B. Comparison of Treatment Effects of Different Iron Chelators in Experimental Models of Sepsis. Life (Basel) 2021; 11:life11010057. [PMID: 33466819 PMCID: PMC7830599 DOI: 10.3390/life11010057] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/09/2021] [Accepted: 01/11/2021] [Indexed: 01/19/2023] Open
Abstract
Growing evidence indicates that dysregulated iron metabolism with altered and excess iron availability in some body compartments plays a significant role in the course of infection and sepsis in humans. Given that all bacterial pathogens require iron for growth, that iron withdrawal is a normal component of innate host defenses and that bacterial pathogens have acquired increasing levels of antibiotic resistance, targeting infection and sepsis through use of appropriate iron chelators has potential to provide new therapeutics. We have directly compared the effects of three Food and Drug Administration (FDA)-approved chelators (deferoxamine—DFO; deferiprone—DFP; and deferasirox—DFX), as were developed for treating hematological iron overload conditions, to DIBI, a novel purpose-designed, anti-infective and anti-inflammatory water-soluble hydroxypyridinone containing iron-selective copolymers. Two murine sepsis models, endotoxemia and polymicrobial abdominal sepsis, were utilized to help differentiate anti-inflammatory versus anti-infective activities of the chelators. Leukocyte adhesion, as measured by intravital microscopy, was observed in both models, with DIBI providing the most effective reduction and DFX the poorest. Inflammation in the abdominal sepsis model, assessed by cytokine measurements, indicated exacerbation by DFX and DFO for plasma Interleukin (IL)-6 and reductions to near-control levels for DIBI and DFP. Peritoneal infection burden was reduced 10-fold by DIBI while DFX and DFP provided no reductions. Overall, the results, together with those from other studies, revealed serious limitations for each of the three hematological chelators, i.e., as potentially repurposed for treating infection/sepsis. In contrast, DIBI provided therapeutic benefits, consistent with various in vitro and in vivo results from other studies, supporting the potential for its use in treating sepsis.
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Affiliation(s)
- Christian Lehmann
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada;
- Correspondence:
| | - Maral Aali
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS B3H 4R2, Canada;
| | - Juan Zhou
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada;
| | - Bruce Holbein
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada;
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13
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Abstract
Studying the pathophysiology of sepsis still requires animal models, and the mouse remains the most commonly used species. Here we discuss the "cecal slurry" (CS) model of polymicrobial, peritoneal sepsis and compare and contrast it to other commonly used methods. Among the different murine models of sepsis, cecal ligation and puncture (CLP), and not the CS, is often considered the "gold standard" to induce polymicrobial sepsis in laboratory animals. CLP is a well-described model involving a simple surgical procedure that closely mimics the clinical course of intra-abdominal sepsis. However, CLP may not be an option for experiments involving newborn pups, where the cecum is indistinguishable from small bowel, where differences in microbiome content may affect the experiment, or where surgical procedures/anesthesia exposure needs to be limited. An important alternative method is the CS model, involving the intraperitoneal injection of cecal contents from a donor animal into the peritoneal cavity of a recipient animal to induce polymicrobial sepsis. Furthermore, CS is an effective alternative model of intraperitoneal polymicrobial sepsis in adult mice and can now be considered the "gold standard" for experiments in neonatal mice.
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14
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Cavaillon J, Singer M, Skirecki T. Sepsis therapies: learning from 30 years of failure of translational research to propose new leads. EMBO Mol Med 2020; 12:e10128. [PMID: 32176432 PMCID: PMC7136965 DOI: 10.15252/emmm.201810128] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/12/2020] [Accepted: 02/17/2020] [Indexed: 12/13/2022] Open
Abstract
Sepsis has been identified by the World Health Organization (WHO) as a global health priority. There has been a tremendous effort to decipher underlying mechanisms responsible for organ failure and death, and to develop new treatments. Despite saving thousands of animals over the last three decades in multiple preclinical studies, no new effective drug has emerged that has clearly improved patient outcomes. In the present review, we analyze the reasons for this failure, focusing on the inclusion of inappropriate patients and the use of irrelevant animal models. We advocate against repeating the same mistakes and propose changes to the research paradigm. We discuss the long-term consequences of surviving sepsis and, finally, list some putative approaches-both old and new-that could help save lives and improve survivorship.
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Affiliation(s)
| | - Mervyn Singer
- Bloomsbury Institute of Intensive Care MedicineUniversity College LondonLondonUK
| | - Tomasz Skirecki
- Laboratory of Flow Cytometry and Department of Anesthesiology and Intensive Care MedicineCentre of Postgraduate Medical EducationWarsawPoland
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15
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16
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Tunctan B, Senol SP, Temiz-Resitoglu M, Guden DS, Sahan-Firat S, Falck JR, Malik KU. Eicosanoids derived from cytochrome P450 pathway of arachidonic acid and inflammatory shock. Prostaglandins Other Lipid Mediat 2019; 145:106377. [PMID: 31586592 DOI: 10.1016/j.prostaglandins.2019.106377] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 09/06/2019] [Accepted: 09/18/2019] [Indexed: 12/14/2022]
Abstract
Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Septic shock, the most common form of vasodilatory shock, is a subset of sepsis in which circulatory and cellular/metabolic abnormalities are severe enough to increase mortality. Inflammatory shock constitutes the hallmark of sepsis, but also a final common pathway of any form of severe long-term tissue hypoperfusion. The pathogenesis of inflammatory shock seems to be due to circulating substances released by pathogens (e.g., bacterial endotoxins) and host immuno-inflammatory responses (e.g., changes in the production of histamine, bradykinin, serotonin, nitric oxide [NO], reactive nitrogen and oxygen species, and arachidonic acid [AA]-derived eicosanoids mainly through NO synthase, cyclooxygenase, and cytochrome P450 [CYP] pathways, and proinflammatory cytokine formation). Therefore, refractory hypotension to vasoconstrictors with end-organ hypoperfusion is a life threatening feature of inflammatory shock. This review summarizes the current knowledge regarding the role of eicosanoids derived from CYP pathway of AA in animal models of inflammatory shock syndromes with an emphasis on septic shock in addition to potential therapeutic strategies targeting specific CYP isoforms responsible for proinflammatory/anti-inflammatory mediator production.
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Affiliation(s)
- Bahar Tunctan
- Department of Pharmacology, Faculty of Pharmacy, Mersin University, Mersin, Turkey.
| | - Sefika Pinar Senol
- Department of Pharmacology, Faculty of Pharmacy, Mersin University, Mersin, Turkey
| | | | - Demet Sinem Guden
- Department of Pharmacology, Faculty of Pharmacy, Mersin University, Mersin, Turkey
| | - Seyhan Sahan-Firat
- Department of Pharmacology, Faculty of Pharmacy, Mersin University, Mersin, Turkey
| | - John R Falck
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kafait U Malik
- Department of Pharmacology, College of Medicine, University of Tennessee, Center for Health Sciences, Memphis, TN, USA
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17
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Assinger A, Schrottmaier WC, Salzmann M, Rayes J. Platelets in Sepsis: An Update on Experimental Models and Clinical Data. Front Immunol 2019; 10:1687. [PMID: 31379873 PMCID: PMC6650595 DOI: 10.3389/fimmu.2019.01687] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/04/2019] [Indexed: 12/22/2022] Open
Abstract
Beyond their important role in hemostasis, platelets play a crucial role in inflammatory diseases. This becomes apparent during sepsis, where platelet count and activation correlate with disease outcome and survival. Sepsis is caused by a dysregulated host response to infection, leading to organ dysfunction, permanent disabilities, or death. During sepsis, tissue injury results from the concomitant uncontrolled activation of the complement, coagulation, and inflammatory systems as well as platelet dysfunction. The balance between the systemic inflammatory response syndrome (SIRS) and the compensatory anti-inflammatory response (CARS) regulates sepsis outcome. Persistent thrombocytopenia is considered as an independent risk factor of mortality in sepsis, although it is still unclear whether the drop in platelet count is the cause or the consequence of sepsis severity. The role of platelets in sepsis development and progression was addressed in different experimental in vivo models, particularly in mice, that represent various aspects of human sepsis. The immunomodulatory function of platelets depends on the experimental model, time, and type of infection. Understanding the molecular mechanism of platelet regulation in inflammation could bring us one step closer to understand this important aspect of primary hemostasis which drives thrombotic as well as bleeding complications in patients with sterile and infectious inflammation. In this review, we summarize the current understanding of the contribution of platelets to sepsis severity and outcome. We highlight the differences between platelet receptors in mice and humans and discuss the potential and limitations of animal models to study platelet-related functions in sepsis.
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Affiliation(s)
- Alice Assinger
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Manuel Salzmann
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Julie Rayes
- Institute of Cardiovascular Science, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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18
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Meneses G, Cárdenas G, Espinosa A, Rassy D, Pérez-Osorio IN, Bárcena B, Fleury A, Besedovsky H, Fragoso G, Sciutto E. Sepsis: developing new alternatives to reduce neuroinflammation and attenuate brain injury. Ann N Y Acad Sci 2018; 1437:43-56. [DOI: 10.1111/nyas.13985] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/02/2018] [Accepted: 10/09/2018] [Indexed: 12/14/2022]
Affiliation(s)
- Gabriela Meneses
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Graciela Cárdenas
- Instituto Nacional de Neurología y Neurocirugía; SSA; Mexico City Mexico
| | - Alejandro Espinosa
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Dunia Rassy
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Ivan Nicolás Pérez-Osorio
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Brandon Bárcena
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Agnes Fleury
- Instituto Nacional de Neurología y Neurocirugía; SSA; Mexico City Mexico
| | - Hugo Besedovsky
- The Institute of Physiology and Pathophysiology, Medical Faculty; Philipps University; Marburg Germany
| | - Gladis Fragoso
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Edda Sciutto
- Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
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19
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Hawkins RB, Raymond SL, Stortz JA, Horiguchi H, Brakenridge SC, Gardner A, Efron PA, Bihorac A, Segal M, Moore FA, Moldawer LL. Chronic Critical Illness and the Persistent Inflammation, Immunosuppression, and Catabolism Syndrome. Front Immunol 2018; 9:1511. [PMID: 30013565 PMCID: PMC6036179 DOI: 10.3389/fimmu.2018.01511] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/18/2018] [Indexed: 12/19/2022] Open
Abstract
Dysregulated host immune responses to infection often occur, leading to sepsis, multiple organ failure, and death. Some patients rapidly recover from sepsis, but many develop chronic critical illness (CCI), a debilitating condition that impacts functional outcomes and long-term survival. The “Persistent Inflammation, Immunosuppression, and Catabolism Syndrome” (PICS) has been postulated as the underlying pathophysiology of CCI. We propose that PICS is initiated by an early genomic and cytokine storm in response to microbial invasion during the early phase of sepsis. However, once source control, antimicrobial coverage, and supportive therapies have been initiated, we propose that the persistent inflammation in patients developing CCI is a result of ongoing endogenous alarmin release from damaged organs and loss of muscle mass. This ongoing alarmin and danger-associated molecular pattern signaling causes chronic inflammation and a shift in bone marrow stem cell production toward myeloid cells, contributing to chronic anemia and lymphopenia. We propose that therapeutic interventions must target the chronic organ injury and lean tissue wasting that contribute to the release of endogenous alarmins and the expansion and deposition of myeloid progenitors that are responsible for the propagation and persistence of CCI.
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Affiliation(s)
- Russell B Hawkins
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Steven L Raymond
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Julie A Stortz
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Hiroyuki Horiguchi
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Scott C Brakenridge
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Anna Gardner
- Department of Aging and Geriatric Research, Institute on Aging, University of Florida College of Medicine, Gainesville, FL, United States
| | - Philip A Efron
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Azra Bihorac
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States.,Division of Nephrology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, United States
| | - Mark Segal
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States.,Division of Nephrology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, United States
| | - Frederick A Moore
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
| | - Lyle L Moldawer
- Sepsis and Critical Illness Research Center, Department of Surgery, University of Florida College of Medicine, Gainesville, FL, United States
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20
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Stortz JA, Raymond SL, Mira JC, Moldawer LL, Mohr AM, Efron PA. Murine Models of Sepsis and Trauma: Can We Bridge the Gap? ILAR J 2017; 58:90-105. [PMID: 28444204 PMCID: PMC5886315 DOI: 10.1093/ilar/ilx007] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 02/20/2017] [Accepted: 02/23/2017] [Indexed: 02/06/2023] Open
Abstract
Sepsis and trauma are both leading causes of death in the United States and represent major public health challenges. Murine models have largely been used in sepsis and trauma research to better understand the pathophysiological changes that occur after an insult and to develop potential life-saving therapeutic agents. Mice are favorable subjects for this type of research given the variety of readily available strains including inbred, outbred, and transgenic strains. In addition, they are relatively easy to maintain and have a high fecundity. However, pharmacological therapies demonstrating promise in preclinical mouse models of sepsis and trauma often fail to demonstrate similar efficacy in human clinical trials, prompting considerable criticism surrounding the capacity of murine models to recapitulate complex human diseases like sepsis and traumatic injury. Fundamental differences between the two species include, but are not limited to, the divergence of the transcriptomic response, the mismatch of temporal response patterns, differences in both innate and adaptive immunity, and heterogeneity within the human population in comparison to the homogeneity of highly inbred mouse strains. Given the ongoing controversy, this narrative review aims to not only highlight the historical importance of the mouse as an animal research model but also highlight the current benefits and limitations of the model as it pertains to sepsis and trauma. Lastly, this review will propose future directions that may promote further use of the model.
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Affiliation(s)
- Julie A. Stortz
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
| | - Steven L. Raymond
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
| | - Juan C. Mira
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
| | - Lyle L. Moldawer
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
| | - Alicia M. Mohr
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
| | - Philip A. Efron
- Julie A. Stortz, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Steven L. Raymond, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Juan C. Mira, MD, is a research fellow at the University of Florida Health Shands Hospital in Gainesville, Florida. Lyle L. Moldawer, PhD, is the Robert H. and Kathleen M. Axline Basic Science Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Alicia M. Mohr, MD, is an Associate Professor of Surgery at the University of Florida College of Medicine in Gainesville, FL. Philip A. Efron, MD, is an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine and Medical Director for the surgical intensive care unit at the University of Florida Health Shands Hospital, Department of Surgery, University of Florida College of Medicine, Gainesville, FL.
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21
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Steele AM, Starr ME, Saito H. Late Therapeutic Intervention with Antibiotics and Fluid Resuscitation Allows for a Prolonged Disease Course with High Survival in a Severe Murine Model of Sepsis. Shock 2017; 47:726-734. [PMID: 27879561 PMCID: PMC5432399 DOI: 10.1097/shk.0000000000000799] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Current animal models of sepsis often incorporate antibiotics to be consistent with clinical standards for treatment of patients in the intensive care unit. However, such experimental intervention is commonly initiated very early after infectious insult, which likely blunts the progression of systemic inflammation and downstream pathology. The objective of this study was to establish an animal model of sepsis with delayed therapeutic intervention, allowing a longer disease course and downstream pathology, but still resulting in a high survival rate. Severe lethal abdominal infection was initiated in young adult (17-18-week-old) C57BL/6 mice by cecal slurry (CS) injection. When initiated early (1- or 6-h post-CS injection), antibiotic treatment (imipenem, 1.5 mg/mouse i.p., twice/day for 5 days) rescued the majority of mice; however, few of these mice showed evidence of bacteremia, cytokinemia, or organ injury. When antibiotic treatment was delayed until late time-points (12- or 24-h post-CS injection) the majority of animals did not survive beyond 48 h. When fluid resuscitation (physiological saline, s.c.) was performed in combination with antibiotic treatment (twice daily) beginning at these late time-points, the majority of mice survived (75%) and showed bacteremia, cytokinemia, organ dysfunction, and prolonged body weight loss (<90% for 4 weeks). We recommend that this new repeated combination treatment with antibiotics and fluids resuscitation be initiated at a late time point after bacteremia becomes evident because this model more closely mimics the downstream pathological characteristics of severe clinical sepsis yet maintains a high survival rate. This model would be advantageous for studies on severe sepsis and postintensive care illness.
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Affiliation(s)
- Allison M. Steele
- Department of Physiology, University of Kentucky, Lexington, KY 40536
| | - Marlene E. Starr
- Department of Surgery, University of Kentucky, Lexington, KY 40536
| | - Hiroshi Saito
- Department of Physiology, University of Kentucky, Lexington, KY 40536
- Department of Surgery, University of Kentucky, Lexington, KY 40536
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536
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22
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Napier BA, Brubaker SW, Sweeney TE, Monette P, Rothmeier GH, Gertsvolf NA, Puschnik A, Carette JE, Khatri P, Monack DM. Complement pathway amplifies caspase-11-dependent cell death and endotoxin-induced sepsis severity. J Exp Med 2016; 213:2365-2382. [PMID: 27697835 PMCID: PMC5068231 DOI: 10.1084/jem.20160027] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 08/25/2016] [Indexed: 01/18/2023] Open
Abstract
Caspase-11–dependent cell death is controlled by carboxypeptidase B1 by inducing the cleavage of C3 and activation of C3aR. Cell death and release of proinflammatory mediators contribute to mortality during sepsis. Specifically, caspase-11–dependent cell death contributes to pathology and decreases in survival time in sepsis models. Priming of the host cell, through TLR4 and interferon receptors, induces caspase-11 expression, and cytosolic LPS directly stimulates caspase-11 activation, promoting the release of proinflammatory cytokines through pyroptosis and caspase-1 activation. Using a CRISPR-Cas9–mediated genome-wide screen, we identified novel mediators of caspase-11–dependent cell death. We found a complement-related peptidase, carboxypeptidase B1 (Cpb1), to be required for caspase-11 gene expression and subsequent caspase-11–dependent cell death. Cpb1 modifies a cleavage product of C3, which binds to and activates C3aR, and then modulates innate immune signaling. We find the Cpb1–C3–C3aR pathway induces caspase-11 expression through amplification of MAPK activity downstream of TLR4 and Ifnar activation, and mediates severity of LPS-induced sepsis (endotoxemia) and disease outcome in mice. We show C3aR is required for up-regulation of caspase-11 orthologues, caspase-4 and -5, in primary human macrophages during inflammation and that c3aR1 and caspase-5 transcripts are highly expressed in patients with severe sepsis; thus, suggesting that these pathways are important in human sepsis. Our results highlight a novel role for complement and the Cpb1–C3–C3aR pathway in proinflammatory signaling, caspase-11 cell death, and sepsis severity.
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Affiliation(s)
- Brooke A Napier
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Sky W Brubaker
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Timothy E Sweeney
- Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford University, Stanford, CA 94305.,Institute for Immunity, Transplantation, and Infection, Stanford University, Stanford, CA 94305
| | - Patrick Monette
- Department of Biology, Middlebury College, Middlebury, VT 05753
| | | | - Nina A Gertsvolf
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Andreas Puschnik
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Jan E Carette
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Purvesh Khatri
- Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford University, Stanford, CA 94305.,Institute for Immunity, Transplantation, and Infection, Stanford University, Stanford, CA 94305
| | - Denise M Monack
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
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23
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Affiliation(s)
- Anthony J. Lewis
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Christopher W. Seymour
- The Clinical Research, Investigation, and Systems Modeling of Acute illness (CRISMA) Center, Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Matthew R. Rosengart
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- The Clinical Research, Investigation, and Systems Modeling of Acute illness (CRISMA) Center, Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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24
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Kan B, Razzaghian HR, Lavoie PM. An Immunological Perspective on Neonatal Sepsis. Trends Mol Med 2016; 22:290-302. [PMID: 26993220 PMCID: PMC5104533 DOI: 10.1016/j.molmed.2016.02.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 02/08/2016] [Indexed: 02/07/2023]
Abstract
Despite concerted international efforts, mortality from neonatal infections remains unacceptably high in some areas of the world, particularly for premature infants. Recent developments in flow cytometry and next-generation sequencing technologies have led to major discoveries over the past few years, providing a more integrated understanding of the developing human immune system in the context of its microbial environment. We review these recent findings, focusing on how in human newborns incomplete maturation of the immune system before a full term of gestation impacts on their vulnerability to infection. We also discuss some of the clinical implications of this research in guiding the design of more-accurate age-adapted diagnostic and preventive strategies for neonatal sepsis.
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Affiliation(s)
- Bernard Kan
- Child and Family Research Institute, Vancouver, British Columbia, Canada; Experimental Medicine Program, Department of Medicine, University of British Columbia, Vancouver, Canada
| | - Hamid Reza Razzaghian
- Child and Family Research Institute, Vancouver, British Columbia, Canada; Experimental Medicine Program, Department of Medicine, University of British Columbia, Vancouver, Canada
| | - Pascal M Lavoie
- Child and Family Research Institute, Vancouver, British Columbia, Canada; Experimental Medicine Program, Department of Medicine, University of British Columbia, Vancouver, Canada; Department of Pediatrics, University of British Columbia, Vancouver, Canada.
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25
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Rasid O, Cavaillon JM. Recent developments in severe sepsis research: from bench to bedside and back. Future Microbiol 2016; 11:293-314. [PMID: 26849633 DOI: 10.2217/fmb.15.133] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Severe sepsis remains a worldwide threat, not only in industrialized countries, due to their aging population, but also in developing countries where there still are numerous cases of neonatal and puerperal sepsis. Tools for early diagnosis, a prerequisite for rapid and appropriate antibiotic therapy, are still required. In this review, we highlight some recent developments in our understanding of the associated systemic inflammatory response that help deciphering pathophysiology (e.g., epigenetic, miRNA, regulatory loops, compartmentalization, apoptosis and synergy) and discuss some of the consequences of sepsis (e.g., immune status, neurological and muscular alterations). We also emphasize the challenge to better define animal models and discuss past failures in clinical investigations in order to define new efficient therapies.
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Affiliation(s)
- Orhan Rasid
- Unit Cytokines & Inflammation, Institut Pasteur, 28 rue Dr. Roux, Paris, France
| | - Jean-Marc Cavaillon
- Unit Cytokines & Inflammation, Institut Pasteur, 28 rue Dr. Roux, Paris, France
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26
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Mira JC, Szpila BE, Nacionales DC, Lopez MC, Gentile LF, Mathias BJ, Vanzant EL, Ungaro R, Holden D, Rosenthal MD, Rincon J, Verdugo PT, Larson SD, Moore FA, Brakenridge SC, Mohr AM, Baker HV, Moldawer LL, Efron PA. Patterns of gene expression among murine models of hemorrhagic shock/trauma and sepsis. Physiol Genomics 2015; 48:135-44. [PMID: 26578697 DOI: 10.1152/physiolgenomics.00072.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/13/2015] [Indexed: 01/22/2023] Open
Abstract
Controversy remains whether the leukocyte genomic response to trauma or sepsis is dependent upon the initiating stimulus. Previous work illustrated poor correlations between historical models of murine trauma and sepsis (i.e., trauma-hemorrhage and lipopolysaccharide injection, respectively). The aim of this study is to examine the early genomic response in improved murine models of sepsis [cecal ligation and puncture (CLP)] and trauma [polytrauma (PT)] with and without pneumonia (PT+Pp). Groups of naïve, CLP, PT, and PT+Pp mice were killed at 2 h, 1 or 3 days. Total leukocytes were isolated for genome-wide expression analysis, and genes that were found to differ from control (false discovery rate adjusted P < 0.001) were assessed for fold-change differences. Spearman correlations were also performed. For all time points combined (CLP, PT, PT+Pp), there were 10,426 total genes that were found to significantly differ from naïve controls. At 2 h, the transcriptomic changes between CLP and PT showed a positive correlation (rs) of 0.446 (P < 0.0001) but were less positive thereafter. Correlations were significantly improved when we limited the analysis to common genes whose expression differed by a 1.5 fold-change. Both pathway and upstream analyses revealed the activation of genes known to be associated with pathogen-associated and damage-associated molecular pattern signaling, and early activation patterns of expression were very similar between polytrauma and sepsis at the earliest time points. This study demonstrates that the early leukocyte genomic response to sepsis and trauma are very similar in mice.
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Affiliation(s)
- Juan C Mira
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Benjamin E Szpila
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Dina C Nacionales
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Maria-Cecilia Lopez
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, Florida
| | - Lori F Gentile
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Brittany J Mathias
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Erin L Vanzant
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Ricardo Ungaro
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - David Holden
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Martin D Rosenthal
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Jaimar Rincon
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Patrick T Verdugo
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Shawn D Larson
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Frederick A Moore
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Scott C Brakenridge
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Alicia M Mohr
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Henry V Baker
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, Florida
| | - Lyle L Moldawer
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
| | - Philip A Efron
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida; and
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27
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Szabo PA, Anantha RV, Shaler CR, McCormick JK, Haeryfar SMM. CD1d- and MR1-Restricted T Cells in Sepsis. Front Immunol 2015; 6:401. [PMID: 26322041 PMCID: PMC4533011 DOI: 10.3389/fimmu.2015.00401] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/22/2015] [Indexed: 12/23/2022] Open
Abstract
Dysregulated immune responses to infection, such as those encountered in sepsis, can be catastrophic. Sepsis is typically triggered by an overwhelming systemic response to an infectious agent(s) and is associated with high morbidity and mortality even under optimal critical care. Recent studies have implicated unconventional, innate-like T lymphocytes, including CD1d- and MR1-restricted T cells as effectors and/or regulators of inflammatory responses during sepsis. These cell types are typified by invariant natural killer T (iNKT) cells, variant NKT (vNKT) cells, and mucosa-associated invariant T (MAIT) cells. iNKT and vNKT cells are CD1d-restricted, lipid-reactive cells with remarkable immunoregulatory properties. MAIT cells participate in antimicrobial defense, and are restricted by major histocompatibility complex-related protein 1 (MR1), which displays microbe-derived vitamin B metabolites. Importantly, NKT and MAIT cells are rapid and potent producers of immunomodulatory cytokines. Therefore, they may be considered attractive targets during the early hyperinflammatory phase of sepsis when immediate interventions are urgently needed, and also in later phases when adjuvant immunotherapies could potentially reverse the dangerous state of immunosuppression. We will highlight recent findings that point to the significance or the therapeutic potentials of NKT and MAIT cells in sepsis and will also discuss what lies ahead in research in this area.
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Affiliation(s)
- Peter A Szabo
- Department of Microbiology and Immunology, Western University , London, ON , Canada
| | - Ram V Anantha
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Division of General Surgery, Department of Medicine, Western University , London, ON , Canada
| | - Christopher R Shaler
- Department of Microbiology and Immunology, Western University , London, ON , Canada
| | - John K McCormick
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Centre for Human Immunology, Western University , London, ON , Canada ; Lawson Health Research Institute , London, ON , Canada
| | - S M Mansour Haeryfar
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Centre for Human Immunology, Western University , London, ON , Canada ; Lawson Health Research Institute , London, ON , Canada ; Division of Clinical Immunology and Allergy, Department of Medicine, Western University , London, ON , Canada
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28
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Markwart R, Condotta SA, Requardt RP, Borken F, Schubert K, Weigel C, Bauer M, Griffith TS, Förster M, Brunkhorst FM, Badovinac VP, Rubio I. Immunosuppression after sepsis: systemic inflammation and sepsis induce a loss of naïve T-cells but no enduring cell-autonomous defects in T-cell function. PLoS One 2014; 9:e115094. [PMID: 25541945 PMCID: PMC4277344 DOI: 10.1371/journal.pone.0115094] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 11/18/2014] [Indexed: 11/25/2022] Open
Abstract
Sepsis describes the life-threatening systemic inflammatory response (SIRS) of an organism to an infection and is the leading cause of mortality on intensive care units (ICU) worldwide. An acute episode of sepsis is characterized by the extensive release of cytokines and other mediators resulting in a dysregulated immune response leading to organ damage and/or death. This initial pro-inflammatory burst often transits into a state of immune suppression characterised by loss of immune cells and T-cell dysfunction at later disease stages in sepsis survivors. However, despite these appreciations, the precise nature of the evoked defect in T-cell immunity in post-acute phases of SIRS remains unknown. Here we present an in-depth functional analysis of T-cell function in post-acute SIRS/sepsis. We document that T-cell function is not compromised on a per cell basis in experimental rodent models of infection-free SIRS (LPS or CpG) or septic peritonitis. Transgenic antigen-specific T-cells feature an unaltered cytokine response if challenged in vivo and ex vivo with cognate antigens. Isolated CD4(+)/CD8(+) T-cells from post-acute septic animals do not exhibit defects in T-cell receptor-mediated activation at the the level of receptor-proximal signalling, activation marker upregulation or expansion. However, SIRS/sepsis induced transient lymphopenia and gave rise to an environment of immune attenuation at post acute disease stages. Thus, systemic inflammation has an acute impact on T-cell numbers and adaptive immunity, but does not cause major cell-autonomous enduring functional defects in T-cells.
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Affiliation(s)
- Robby Markwart
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | | | - Robert P. Requardt
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | - Farina Borken
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | - Katja Schubert
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | - Cynthia Weigel
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | - Michael Bauer
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
- Dept. for Anaesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
| | - Thomas S. Griffith
- Minneapolis Veterans Affairs Health Care System, Minneapolis, Minnesota, United States of America
- Center for Immunology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Martin Förster
- Clinic of Internal Medicine I, Jena University Hospital, Jena, Germany
| | - Frank M. Brunkhorst
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
- Center for Clinical Studies, Jena University Hospital, Jena, Germany
| | | | - Ignacio Rubio
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Jena University Hospital, Jena, Germany
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29
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Starr ME, Steele AM, Saito M, Hacker BJ, Evers BM, Saito H. A new cecal slurry preparation protocol with improved long-term reproducibility for animal models of sepsis. PLoS One 2014; 9:e115705. [PMID: 25531402 PMCID: PMC4274114 DOI: 10.1371/journal.pone.0115705] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 11/26/2014] [Indexed: 01/29/2023] Open
Abstract
Sepsis, a life-threatening systemic inflammatory response syndrome induced by infection, is widely studied using laboratory animal models. While cecal-ligation and puncture (CLP) is considered the gold standard model for sepsis research, it may not be preferable for experiments comparing animals of different size or under different dietary regimens. By comparing cecum size, shape, and cecal content characteristics in mice under different experimental conditions (aging, diabetes, pancreatitis), we show that cecum variability could be problematic for some CLP experiments. The cecal slurry (CS) injection model, in which the cecal contents of a laboratory animal are injected intraperitoneally to other animals, is an alternative method for inducing polymicrobial sepsis; however, the CS must be freshly prepared under conventional protocols, which is a major disadvantage with respect to reproducibility and convenience. The objective of this study was to develop an improved CS preparation protocol that allows for long-term storage of CS with reproducible results. Using our new CS preparation protocol we found that bacterial viability is maintained for at least 6 months when the CS is prepared in 15% glycerol-PBS and stored at -80°C. To test sepsis-inducing efficacy of stored CS stocks, various amounts of CS were injected to young (4-6 months old), middle-aged (12-14 months old), and aged (24-26 months old) male C57BL/6 mice. Dose- and age-dependent mortality was observed with high reproducibility. Circulating bacteria levels strongly correlated with mortality suggesting an infection-mediated death. Further, injection with heat-inactivated CS resulted in acute hypothermia without mortality, indicating that CS-mediated death is not due to endotoxic shock. This new CS preparation protocol results in CS stocks which are durable for freezing preservation without loss of bacterial viability, allowing experiments to be performed more conveniently and with higher reproducibility than before.
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Affiliation(s)
- Marlene E. Starr
- Aging and Critical Care Research Laboratory, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Department of Surgery, University of Kentucky, Lexington, Kentucky, 40536, United States of America
| | - Allison M. Steele
- Aging and Critical Care Research Laboratory, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Department of Physiology, University of Kentucky, Lexington, Kentucky, 40536, United States of America
| | - Mizuki Saito
- Aging and Critical Care Research Laboratory, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40536, United States of America
| | - Bill J. Hacker
- Department of Surgery, University of Kentucky, Lexington, Kentucky, 40536, United States of America
| | - B. Mark Evers
- Department of Surgery, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40536, United States of America
| | - Hiroshi Saito
- Aging and Critical Care Research Laboratory, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Department of Surgery, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Department of Physiology, University of Kentucky, Lexington, Kentucky, 40536, United States of America
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, 40536, United States of America
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30
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Anantha RV, Mazzuca DM, Xu SX, Porcelli SA, Fraser DD, Martin CM, Welch I, Mele T, Haeryfar SMM, McCormick JK. T helper type 2-polarized invariant natural killer T cells reduce disease severity in acute intra-abdominal sepsis. Clin Exp Immunol 2014; 178:292-309. [PMID: 24965554 DOI: 10.1111/cei.12404] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2014] [Indexed: 01/09/2023] Open
Abstract
Sepsis is characterized by a severe systemic inflammatory response to infection that is associated with high morbidity and mortality despite optimal care. Invariant natural killer T (iNK T) cells are potent regulatory lymphocytes that can produce pro- and/or anti-inflammatory cytokines, thus shaping the course and nature of immune responses; however, little is known about their role in sepsis. We demonstrate here that patients with sepsis/severe sepsis have significantly elevated proportions of iNK T cells in their peripheral blood (as a percentage of their circulating T cells) compared to non-septic patients. We therefore investigated the role of iNK T cells in a mouse model of intra-abdominal sepsis (IAS). Our data show that iNK T cells are pathogenic in IAS, and that T helper type 2 (Th2) polarization of iNK T cells using the synthetic glycolipid OCH significantly reduces mortality from IAS. This reduction in mortality is associated with the systemic elevation of the anti-inflammatory cytokine interleukin (IL)-13 and reduction of several proinflammatory cytokines within the spleen, notably interleukin (IL)-17. Finally, we show that treatment of sepsis with OCH in mice is accompanied by significantly reduced apoptosis of splenic T and B lymphocytes and macrophages, but not natural killer cells. We propose that modulation of iNK T cell responses towards a Th2 phenotype may be an effective therapeutic strategy in early sepsis.
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Affiliation(s)
- R V Anantha
- Division of General Surgery, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada; Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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