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Xian Y, Xie D, Zhu J, Zheng C, Fan M, Jiang K, Zhang K. Association between intracellular adenosine triphosphate content of CD4 + T lymphocytes and mortality in sepsis patients: A prospective observational study. Immun Inflamm Dis 2024; 12:e1286. [PMID: 38860755 PMCID: PMC11165683 DOI: 10.1002/iid3.1286] [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: 02/06/2024] [Revised: 05/07/2024] [Accepted: 05/13/2024] [Indexed: 06/12/2024] Open
Abstract
OBJECTIVE This study aimed to link intracellular adenosine triphosphate content in CD4+ T lymphocytes (CD4+ iATP) with sepsis patient mortality, seeking a new predictive biomarker for outcomes and enhanced management. METHODS 61 sepsis patients admitted to the Intensive Care Unit between October 2021 and November 2022 were enrolled. iATP levels were gauged using whole blood CD4+ T cells stimulated with mitogen PHA-L. Based on CD4+ iATP levels (<132.24 and ≥132.24 ng/mL), patients were categorized into two groups. The primary endpoint was all-cause mortality. To identify factors associated with mortality, both univariate and multivariate Cox proportional hazard analyses were conducted. RESULTS Of the patients, 40 had high CD4+ iATP levels (≥132.24 ng/mL) and 21 had low levels (<132.24 ng/mL). In a 28-day follow-up, 21 (34.4%) patients perished. Adjusting for confounders like SOFA score, APACHE II score, lactic acid, and albumin, those with low CD4+ iATP had three- to fivefold higher mortality risk compared to high CD4+ iATP patients (61.9% vs. 20.0%; hazard ratio [95% confidence interval], Model 1: 4.515 [1.276-15.974], p = .019, Model 2: 3.512 [1.197-10.306], p = .022). CD4+ iATP correlated positively with white blood cell and neutrophil counts but not with lymphocytes, CD3, and CD4 counts. CONCLUSIONS Low CD4+ iATP levels were associated with a higher risk of mortality in sepsis patients. Measurement of CD4+ iATP may serve as a useful tool for identifying patients at a higher risk of mortality and could potentially provide a basis for clinical treatment. Further research is warranted to fully elucidate the underlying mechanisms of this association.
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Affiliation(s)
- Ying Xian
- Department of General Intensive Care Unit, Lingnan HospitalThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Dan Xie
- Department of General Intensive Care Unit, Lingnan HospitalThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Jian Zhu
- Department of Emergency Intensive Care UnitThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Changlong Zheng
- Department of Emergency Intensive Care UnitThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Min Fan
- Department of General Intensive Care Unit, Lingnan HospitalThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Kefeng Jiang
- Department of Parasitology, Zhongshan School of MedicineSun Yat‐Sen UniversityGuangzhouPeople's Republic of China
| | - Kouxing Zhang
- Department of General Intensive Care Unit, Lingnan HospitalThe Third Affiliated Hospital of Sun Yat‐Sen UniversityGuangzhouPeople's Republic of China
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Huang S, Liu D, Han L, Deng J, Wang Z, Jiang J, Zeng L. Decoding the potential role of regulatory T cells in sepsis-induced immunosuppression. Eur J Immunol 2024; 54:e2350730. [PMID: 38430202 DOI: 10.1002/eji.202350730] [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: 08/24/2023] [Revised: 02/14/2024] [Accepted: 02/16/2024] [Indexed: 03/03/2024]
Abstract
Sepsis, a multiorgan dysfunction with high incidence and mortality, is caused by an imbalanced host-to-infection immune response. Organ-support therapy improves the early survival rate of sepsis patients. In the long term, those who survive the "cytokine storm" and its secondary damage usually show higher susceptibility to secondary infections and sepsis-induced immunosuppression, in which regulatory T cells (Tregs) are evidenced to play an essential role. However, the potential role and mechanism of Tregs in sepsis-induced immunosuppression remains elusive. In this review, we elucidate the role of different functional subpopulations of Tregs during sepsis and then review the mechanism of sepsis-induced immunosuppression from the aspects of regulatory characteristics, epigenetic modification, and immunometabolism of Tregs. Thoroughly understanding how Tregs impact the immune system during sepsis may shed light on preclinical research and help improve the translational value of sepsis immunotherapy.
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Affiliation(s)
- Siyuan Huang
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
| | - Di Liu
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
| | - Lei Han
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
| | - Jin Deng
- Department of Emergency, the Affiliated Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, China
| | - Zhen Wang
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
| | - Jianxin Jiang
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
| | - Ling Zeng
- Department of Trauma Medical Center, Daping Hospital, State Key Laboratory of Trauma and Chemical Poisoning, Army Medical University, Chongqing, China
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Fu X, Liu Z, Wang Y. Advances in the Study of Immunosuppressive Mechanisms in Sepsis. J Inflamm Res 2023; 16:3967-3981. [PMID: 37706064 PMCID: PMC10497210 DOI: 10.2147/jir.s426007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/29/2023] [Indexed: 09/15/2023] Open
Abstract
Sepsis is a life-threatening disease caused by a systemic infection that triggers a dysregulated immune response. Sepsis is an important cause of death in intensive care units (ICUs), poses a major threat to human health, and is a common cause of death in ICUs worldwide. The pathogenesis of sepsis is intricate and involves a complex interplay of pro- and anti-inflammatory mechanisms that can lead to excessive inflammation, immunosuppression, and potentially long-term immune disorders. Recent evidence highlights the importance of immunosuppression in sepsis. Immunosuppression is recognized as a predisposing factor for increased susceptibility to secondary infections and mortality in patients. Immunosuppression due to sepsis increases a patient's chance of re-infection and increases organ load. In addition, antibiotics, fluid resuscitation, and organ support therapy have limited impact on the prognosis of septic patients. Therapeutic approaches by suppressing excessive inflammation have not achieved the desired results in clinical trials. Research into immunosuppression has brought new hope for the treatment of sepsis, and a number of therapeutic approaches have demonstrated the potential of immunostimulatory therapies. In this article, we will focus on the mechanisms of immunosuppression and markers of immune monitoring in sepsis and describe various targets for immunostimulatory therapy in sepsis.
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Affiliation(s)
- Xuzhe Fu
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, People’s Republic of China
| | - Zhi Liu
- Department of Ophthalmology, Shengjing Hospital of China Medical University, Shenyang, People’s Republic of China
| | - Yu Wang
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, People’s Republic of China
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Ghafil FA, Majeed SA, Qassam H, Mardan HW, Hadi NR. NEPHROPROTECTIVE EFFECT OF GAMMA-SECRETASE INHIBITOR ON SEPSIS- INDUCED RENAL INJURY IN MOUSE MODEL OF CLP. WIADOMOSCI LEKARSKIE (WARSAW, POLAND : 1960) 2023; 76:122-130. [PMID: 36883500 DOI: 10.36740/wlek202301117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
OBJECTIVE The aim: This study was set out to assess the potential protective impact of MK0752 (a gamma secretase inhibitor) on sepsis-induced renal injury through modulation of inflammatory and oxidative stress pathways. PATIENTS AND METHODS Materials and methods: Twenty-four Swiss-albino mice aged between eight and twelve week and weighted twenty to thirty-seven grams were randomly allocated into four groups (n=6 in each group). Sham group (laparotomy without cecal ligation and puncture (CLP), sepsis group (laparotomy with CLP), vehicle-treated group (equivalent volume of DMSO before the CLP), MK0752 treated group (5 mg/kg) single daily dose for three days before the CLP. Blood samples were used to assess the serum levels of urea and creatinine. The kidneys were used to assess tissue levels of the TNF-α, IL-10, IL-6, TNFR1, VEGF, notch1, jagged1 and tissue damage by histopathological analysis. RESULTS Results: The current study shows that pretreatment with MK0752 ameliorates the renal damage by significantly reducing the proinflammatory cytokines and notch1 signaling. CONCLUSION Conclusions: Taken together, these results suggest that MK0752 could be protective against the renal injury induced by sepsis through its ameliorative impact on renal architecture and modulating cytokines and Notch1 singling pathway. Further studies regarding the role of Notch signaling pathways would be worthwhile.
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Affiliation(s)
- Fadha Abdulameer Ghafil
- DEPARTMENT OF PHARMACOLOGY AND THERAPEUTICS, FACULTY OF MEDICINE, UNIVERSITY OF KUFA, NAJAF, IRAQ
| | - Sahar A Majeed
- DEPARTMENT OF PHARMACOLOGY AND THERAPEUTICS, FACULTY OF MEDICINE, UNIVERSITY OF KUFA, NAJAF, IRAQ
| | - Heider Qassam
- DEPARTMENT OF PHARMACOLOGY AND THERAPEUTICS, FACULTY OF MEDICINE, UNIVERSITY OF KUFA, NAJAF, IRAQ
| | - Haider W Mardan
- MIDDLE EUPHRATES CENTER OF NEUROSCIENCES, AL-SADDER TEACHING HOSPITAL, NAJAF, IRAQ
| | - Najah R Hadi
- MIDDLE EUPHRATES CENTER OF NEUROSCIENCES, AL-SADDER TEACHING HOSPITAL, NAJAF, IRAQ
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Bioinformatics Analysis Identifies TNFRSF1A as a Biomarker of Liver Injury in Sepsis TNFRSF1A is a Biomarker for Septic Liver Injury. Genet Res (Camb) 2022; 2022:1493744. [PMID: 36299685 PMCID: PMC9587912 DOI: 10.1155/2022/1493744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/26/2022] [Accepted: 09/29/2022] [Indexed: 11/18/2022] Open
Abstract
Sepsis is a severe disease with high mortality, and liver injury is an independent risk factor for sepsis morbidity and mortality. We analyzed co-differentially expressed genes (co-DEGs) to explore potential biomarkers and therapeutic targets for sepsis-related liver injury. Three gene expression datasets (GSE60088, GSE23767, and GSE71530) were downloaded from the Gene Expression Omnibus (GEO). DEGs were screened between sepsis and control samples using GEO2R. The association of these DEGs with infection and liver disease was analyzed by using the CTD database. GO functional analysis, KEGG pathway enrichment analysis, and protein-protein interaction (PPI) network analysis were performed to elucidate the potential molecular mechanism of DEGs. DEGs of different tissues in GSE60088 were analyzed again to obtain specific markers of septic liver injury. Mouse model of sepsis was also established by cecal ligation and puncture (CLP), and the expression of specific markers in liver, lung, and kidney tissues was analyzed using Western blot. Here, we identified 21 DEGs in three datasets with 8 hub genes, all of which showed higher inference scores in liver diseases than bacterial infections. Among them, only TNFRSF1A had a liver-specific differential expression. TNFRSF1A was also confirmed to be specifically reduced in septic liver tissues in mice. Therefore, TNFRSF1A may serve as a potential biomarker for septic liver injury.
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Kumar V, Rosenzweig R, Asalla S, Nehra S, Prabhu SD, Bansal SS. TNFR1 Contributes to Activation-Induced Cell Death of Pathological CD4 + T Lymphocytes During Ischemic Heart Failure. JACC Basic Transl Sci 2022; 7:1038-1049. [PMID: 36337927 PMCID: PMC9626895 DOI: 10.1016/j.jacbts.2022.05.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/09/2022] [Accepted: 05/09/2022] [Indexed: 10/17/2022]
Abstract
CD4+ T cells turn pathological during heart failure (HF). We show that the expression of tumor necrosis factor (TNF)-α and tumor necrosis factor receptor (TNFR1) increases in HF-activated CD4+ T cells. However, the role of the TNF-α/TNFR1 axis in T-cell activation/proliferation is unknown. We show that TNFR1 neutralization during T-cell activation (ex vivo) or the loss of TNFR1 in adoptively transferred HF-activated CD4+ T cells (in vivo) augments their prosurvival and proliferative signaling. Importantly, TNFR1 neutralization does not affect CD69 expression or the pathological activity of HF-activated TNFR1-/- CD4+ T cells. These results show that during HF TNFR1 plays an important role in quelling prosurvival and proliferative signals in CD4+ T cells without altering their pathological activity.
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Key Words
- AT, adoptive transfer
- HF, heart failure
- IL, interleukin
- LV, left ventricular
- MFI, mean fluorescence intensity
- MI, myocardial infarction
- PBS, phosphate-buffered saline
- T lymphocytes
- TCR, T-cell receptor
- TNF, tumor necrosis factor
- TNFR1, tumor necrosis factor receptor 1
- Tcm, memory T cell
- WT, wild type
- heart failure
- left ventricular remodeling
- mLN, mediastinal lymph node
- myocardial infarction
- tumor necrosis factor receptors
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Affiliation(s)
- Vinay Kumar
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Rachel Rosenzweig
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Suman Asalla
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Sarita Nehra
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Sumanth D. Prabhu
- Division of Cardiology, Department of Medicine, Washington University, St Louis, Missouri, USA
| | - Shyam S. Bansal
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,Address for correspondence: Dr Shyam S. Bansal, Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, 473 W 12th Avenue, Columbus, Ohio 43210, USA.
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Sehgal R, Kaur N, Ramakrishna G, Trehanpati N. Immune Surveillance by Myeloid-Derived Suppressor Cells in Liver Diseases. Dig Dis 2021; 40:301-312. [PMID: 34157708 DOI: 10.1159/000517459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 05/27/2021] [Indexed: 02/02/2023]
Abstract
BACKGROUND Myeloid-derived suppressor cells (MDSCs) are immunosuppressive in nature, originate in the bone marrow, and are mainly found in the blood, spleen, and liver. In fact, liver acts as an important organ for induction and accumulation of MDSCs, especially during infection, inflammation, and cancer. In humans and rodents, models of liver diseases revealed that MDSCs promote regeneration and drive the inflammatory processes, leading to hepatitis, fibrogenesis, and cirrhosis, ultimately resulting in hepatocellular carcinoma. SUMMARY This brief review is focused on the in-depth understanding of the key molecules involved in the expansion and regulation of MDSCs and their underlying immunosuppressive mechanisms in liver diseases. KEY MESSAGE Modulated MDSCs can be used for therapeutic purposes in inflammation, cancer, and sepsis.
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Affiliation(s)
- Rashi Sehgal
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India.,Amity Institute of Biotechnology (AIB), Amity University, Noida, India
| | - Navkiran Kaur
- Amity Institute of Biotechnology (AIB), Amity University, Noida, India
| | - Gayatri Ramakrishna
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Nirupma Trehanpati
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
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de Morais SD, Kak G, Menousek JP, Kielian T. Immunopathogenesis of Craniotomy Infection and Niche-Specific Immune Responses to Biofilm. Front Immunol 2021; 12:625467. [PMID: 33708216 PMCID: PMC7940520 DOI: 10.3389/fimmu.2021.625467] [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: 11/03/2020] [Accepted: 01/05/2021] [Indexed: 02/06/2023] Open
Abstract
Bacterial infections in the central nervous system (CNS) can be life threatening and often impair neurological function. Biofilm infection is a complication following craniotomy, a neurosurgical procedure that involves the removal and replacement of a skull fragment (bone flap) to access the brain for surgical intervention. The incidence of infection following craniotomy ranges from 1% to 3% with approximately half caused by Staphylococcus aureus (S. aureus). These infections present a significant therapeutic challenge due to the antibiotic tolerance of biofilm and unique immune properties of the CNS. Previous studies have revealed a critical role for innate immune responses during S. aureus craniotomy infection. Experiments using knockout mouse models have highlighted the importance of the pattern recognition receptor Toll-like receptor 2 (TLR2) and its adaptor protein MyD88 for preventing S. aureus outgrowth during craniotomy biofilm infection. However, neither molecule affected bacterial burden in a mouse model of S. aureus brain abscess highlighting the distinctions between immune regulation of biofilm vs. planktonic infection in the CNS. Furthermore, the immune responses elicited during S. aureus craniotomy infection are distinct from biofilm infection in the periphery, emphasizing the critical role for niche-specific factors in dictating S. aureus biofilm-leukocyte crosstalk. In this review, we discuss the current knowledge concerning innate immunity to S. aureus craniotomy biofilm infection, compare this to S. aureus biofilm infection in the periphery, and discuss the importance of anatomical location in dictating how biofilm influences inflammatory responses and its impact on bacterial clearance.
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Affiliation(s)
- Sharon Db de Morais
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Gunjan Kak
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Joseph P Menousek
- Department of Neurosurgery, University of Nebraska Medical Center, Omaha, NE, United States
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
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Gough P, Myles IA. Tumor Necrosis Factor Receptors: Pleiotropic Signaling Complexes and Their Differential Effects. Front Immunol 2020; 11:585880. [PMID: 33324405 PMCID: PMC7723893 DOI: 10.3389/fimmu.2020.585880] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 11/02/2020] [Indexed: 12/15/2022] Open
Abstract
Since its discovery in 1975, TNFα has been a subject of intense study as it plays significant roles in both immunity and cancer. Such attention is well deserved as TNFα is unique in its engagement of pleiotropic signaling via its two receptors: TNFR1 and TNFR2. Extensive research has yielded mechanistic insights into how a single cytokine can provoke a disparate range of cellular responses, from proliferation and survival to apoptosis and necrosis. Understanding the intracellular signaling pathways induced by this single cytokine via its two receptors is key to further revelation of its exact functions in the many disease states and immune responses in which it plays a role. In this review, we describe the signaling complexes formed by TNFR1 and TNFR2 that lead to each potential cellular response, namely, canonical and non-canonical NF-κB activation, apoptosis and necrosis. This is followed by a discussion of data from in vivo mouse and human studies to examine the differential impacts of TNFR1 versus TNFR2 signaling.
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Affiliation(s)
- Portia Gough
- Epithelial Therapeutics Unit, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD, United States
| | - Ian A Myles
- Epithelial Therapeutics Unit, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD, United States
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Uebele J, Habenicht K, Ticha O, Bekeredjian-Ding I. Staphylococcus aureus Protein A Induces Human Regulatory T Cells Through Interaction With Antigen-Presenting Cells. Front Immunol 2020; 11:581713. [PMID: 33117390 PMCID: PMC7560526 DOI: 10.3389/fimmu.2020.581713] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/14/2020] [Indexed: 11/13/2022] Open
Abstract
Despite continuous exposure and development of specific immunity, Staphylococcus aureus (Sa) remains one of the leading causes of severe infections worldwide. Although innate immune defense mechanisms are well understood, the role of the T cell response has not been fully elucidated. Here, we demonstrate that Sa and one of its major virulence factors protein A (SpA) induce human regulatory T cells (Tregs), key players in immune tolerance. In human PBMC and MoDC/T cell cocultures CD4+CD25+CD127dim Tregs were induced upon stimulation with Sa and to a lower extent with SpA alone. Treg induction was strongly, but not exclusively, dependent on SpA, and independent of antigen presentation or T cell epitope recognition. Lastly, soluble factors in the supernatant of SpA-stimulated MoDC were sufficient to trigger Treg formation, while supernatants of MoDC/T cell cocultures containing Sa-triggered Tregs displayed T cell suppressive activity. In summary, our findings identify a new immunosuppressory function of SpA, which leads to release of soluble, Treg-inducing factors and might be relevant to establish colonization.
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Affiliation(s)
- Julia Uebele
- Division of Microbiology, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Olga Ticha
- Division of Microbiology, Paul-Ehrlich-Institut, Langen, Germany
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Campoccia D, Mirzaei R, Montanaro L, Arciola CR. Hijacking of immune defences by biofilms: a multifront strategy. BIOFOULING 2019; 35:1055-1074. [PMID: 31762334 DOI: 10.1080/08927014.2019.1689964] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/05/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Biofilm formation by pathogens and opportunistic bacteria is the basis of persistent or recurrent infections. Up to 80% of bacterial infections in humans are associated with biofilms. Despite the efficiency of the evolved and complex human defence system against planktonic bacteria, biofilms are capable of subverting host defences. The immune system is not completely effective in opposing bacteria and preventing infection. Increasing attention is being focussed on the mechanisms enabling bacterial biofilms to skew the coordinate action of humoral and cell mediated responses. Knowledge of the interactions between biofilm bacteria and the immune system is critical to effectively address biofilm infections, which have multiplied over the years with the spread of biomaterials in medicine. In this article, the latest information on the interactions between bacterial biofilms and immune cells is examined and the areas where of information is still lacking are explored.
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Affiliation(s)
- Davide Campoccia
- Laboratorio di Patologia delle Infezioni Associate all'Impianto, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Rasoul Mirzaei
- Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Lucio Montanaro
- Laboratorio di Patologia delle Infezioni Associate all'Impianto, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- Department of Experimental, Diagnostic, and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Carla Renata Arciola
- Laboratorio di Patologia delle Infezioni Associate all'Impianto, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- Department of Experimental, Diagnostic, and Specialty Medicine, University of Bologna, Bologna, Italy
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Heterogeneity of Ly6G + Ly6C + Myeloid-Derived Suppressor Cell Infiltrates during Staphylococcus aureus Biofilm Infection. Infect Immun 2018; 86:IAI.00684-18. [PMID: 30249747 DOI: 10.1128/iai.00684-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 09/20/2018] [Indexed: 01/11/2023] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature monocytes and granulocytes. While neutrophils (polymorphonuclear leukocytes [PMNs]) are classically identified as highly differentiated cells specialized for antimicrobial defense, our laboratory has reported minor contributions of PMNs to the immune response during Staphylococcus aureus biofilm infection. However, these two cell types can be difficult to differentiate because of shared surface marker expression. Here we describe a more refined approach to distinguish MDSCs from PMNs utilizing the integrin receptor CD11b combined with conventional Ly6G and Ly6C expression. This approach separated the Ly6G+ Ly6C+ population that we previously identified in a mouse model of S. aureus orthopedic implant infection into two subsets, namely, CD11bhigh Ly6G+ Ly6C+ MDSCs and CD11blow Ly6G+ Ly6C+ PMNs, which was confirmed by characteristic nuclear morphology using cytospins. CD11bhigh Ly6G+ Ly6C+ MDSCs suppressed T cell proliferation throughout the 28-day infection period, whereas CD11blow Ly6G+ Ly6C+ PMNs had no effect early (day 3 postinfection), although this population acquired suppressive activity at later stages of biofilm development. To further highlight the distinctions between biofilm-associated MDSCs and PMNs versus monocytes, transcriptional profiles were compared by transcriptome sequencing (RNA-Seq). A total of 6,466 genes were significantly differentially expressed in MDSCs versus monocytes, whereas only 297 genes were significantly different between MDSCs and PMNs. A number of genes implicated in cell cycle regulation were identified, and in vivo ethynyldeoxyuridine (EdU) labeling revealed that approximately 50% of MDSCs proliferated locally at the site of S. aureus biofilm infection. Based on their similar transcriptomic profiles to those of PMNs, biofilm-associated MDSCs are of a granulocytic lineage and can be classified as granulocytic MDSCs (G-MDSCs).
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