1
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Al-Bahou R, Bruner J, Moore H, Zarrinpar A. Quantitative methods for optimizing patient outcomes in liver transplantation. Liver Transpl 2024; 30:311-320. [PMID: 38153309 DOI: 10.1097/lvt.0000000000000325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/11/2023] [Indexed: 12/29/2023]
Abstract
Liver transplantation (LT) is a lifesaving yet complex intervention with considerable challenges impacting graft and patient outcomes. Despite best practices, 5-year graft survival is only 70%. Sophisticated quantitative techniques offer potential solutions by assimilating multifaceted data into insights exceeding human cognition. Optimizing donor-recipient matching and graft allocation presents additional intricacies, involving the integration of clinical and laboratory data to select the ideal donor and recipient pair. Allocation must balance physiological variables with geographical and logistical constraints and timing. Quantitative methods can integrate these complex factors to optimize graft utilization. Such methods can also aid in personalizing treatment regimens, drawing on both pretransplant and posttransplant data, possibly using continuous immunological monitoring to enable early detection of graft injury or infected states. Advanced analytics is thus poised to transform management in LT, maximizing graft and patient survival. In this review, we describe quantitative methods applied to organ transplantation, with a focus on LT. These include quantitative methods for (1) utilizing and allocating donor organs equitably and optimally, (2) improving surgical planning through preoperative imaging, (3) monitoring graft and immune status, (4) determining immunosuppressant doses, and (5) establishing and maintaining the health of graft and patient after LT.
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Affiliation(s)
- Raja Al-Bahou
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Julia Bruner
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Helen Moore
- Department of Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Ali Zarrinpar
- Department of Surgery, University of Florida College of Medicine, Gainesville, Florida, USA
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2
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Habibabady Z, McGrath G, Kinoshita K, Maenaka A, Ikechukwu I, Elias GF, Zaletel T, Rosales I, Hara H, Pierson RN, Cooper DKC. Antibody-mediated rejection in xenotransplantation: Can it be prevented or reversed? Xenotransplantation 2023; 30:e12816. [PMID: 37548030 PMCID: PMC11101061 DOI: 10.1111/xen.12816] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 08/08/2023]
Abstract
Antibody-mediated rejection (AMR) is the commonest cause of failure of a pig graft after transplantation into an immunosuppressed nonhuman primate (NHP). The incidence of AMR compared to acute cellular rejection is much higher in xenotransplantation (46% vs. 7%) than in allotransplantation (3% vs. 63%) in NHPs. Although AMR in an allograft can often be reversed, to our knowledge there is no report of its successful reversal in a pig xenograft. As there is less experience in preventing or reversing AMR in models of xenotransplantation, the results of studies in patients with allografts provide more information. These include (i) depletion or neutralization of serum anti-donor antibodies, (ii) inhibition of complement activation, (iii) therapies targeting B or plasma cells, and (iv) anti-inflammatory therapy. Depletion or neutralization of anti-pig antibody, for example, by plasmapheresis, is effective in depleting antibodies, but they recover within days. IgG-degrading enzymes do not deplete IgM. Despite the expression of human complement-regulatory proteins on the pig graft, inhibition of systemic complement activation may be necessary, particularly if AMR is to be reversed. Potential therapies include (i) inhibition of complement activation (e.g., by IVIg, C1 INH, or an anti-C5 antibody), but some complement inhibitors are not effective in NHPs, for example, eculizumab. Possible B cell-targeted therapies include (i) B cell depletion, (ii) plasma cell depletion, (iii) modulation of B cell activation, and (iv) enhancing the generation of regulatory B and/or T cells. Among anti-inflammatory agents, anti-IL6R mAb and TNF blockers are increasingly being tested in xenotransplantation models, but with no definitive evidence that they reverse AMR. Increasing attention should be directed toward testing combinations of the above therapies. We suggest that treatment with a systemic complement inhibitor is likely to be most effective, possibly combined with anti-inflammatory agents (if these are not already being administered). Ultimately, it may require further genetic engineering of the organ-source pig to resolve the problem entirely, for example, knockout or knockdown of SLA, and/or expression of PD-L1, HLA E, and/or HLA-G.
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Affiliation(s)
- Zahra Habibabady
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Gannon McGrath
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Kohei Kinoshita
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Akihiro Maenaka
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Ileka Ikechukwu
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Gabriela F. Elias
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Tjasa Zaletel
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Ivy Rosales
- Department of Pathology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Hidetaka Hara
- Yunnan Xenotransplantation Engineering Research Center, Yunnan Agricultural University, Kunming, Yunnan, China
| | - Richard N. Pierson
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - David K. C. Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
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3
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Lapp MM, Lin G, Komin A, Andrews L, Knudson M, Mossman L, Raimondi G, Arciero JC. Modeling the Potential of Treg-Based Therapies for Transplant Rejection: Effect of Dose, Timing, and Accumulation Site. Transpl Int 2022; 35:10297. [PMID: 35479106 PMCID: PMC9035492 DOI: 10.3389/ti.2022.10297] [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: 12/10/2021] [Accepted: 03/17/2022] [Indexed: 02/04/2023]
Abstract
Introduction: The adoptive transfer of regulatory T cells (Tregs) has emerged as a method to promote graft tolerance. Clinical trials have demonstrated the safety of adoptive transfer and are now assessing their therapeutic efficacy. Strategies that generate large numbers of antigen specific Tregs are even more efficacious. However, the combinations of factors that influence the outcome of adoptive transfer are too numerous to be tested experimentally. Here, mathematical modeling is used to predict the most impactful treatment scenarios. Methods: We adapted our mathematical model of murine heart transplant rejection to simulate Treg adoptive transfer and to correlate therapeutic efficacy with Treg dose and timing, frequency of administration, and distribution of injected cells. Results: The model predicts that Tregs directly accumulating to the graft are more protective than Tregs localizing to draining lymph nodes. Inhibiting antigen-presenting cell maturation and effector functions at the graft site was more effective at modulating rejection than inhibition of T cell activation in lymphoid tissues. These complex dynamics define non-intuitive relationships between graft survival and timing and frequency of adoptive transfer. Conclusion: This work provides the framework for better understanding the impact of Treg adoptive transfer and will guide experimental design to improve interventions.
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Affiliation(s)
- Maya M. Lapp
- Department of Mathematics, The College of Wooster, Wooster, OH, United States
| | - Guang Lin
- Department of Mathematics, Purdue University, West Lafayette, IN, United States
| | - Alexander Komin
- Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Leah Andrews
- Department of Mathematics, St. Olaf College, Northfield, MN, United States
| | - Mei Knudson
- Department of Mathematics, Carleton College, Northfield, MN, United States
| | - Lauren Mossman
- Department of Mathematics, St. Olaf College, Northfield, MN, United States
| | - Giorgio Raimondi
- Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine, Baltimore, MD, United States,*Correspondence: Giorgio Raimondi, ; Julia C. Arciero,
| | - Julia C. Arciero
- Department of Mathematical Sciences, Indiana University-Purdue University of Indianapolis, Indianapolis, IN, United States,*Correspondence: Giorgio Raimondi, ; Julia C. Arciero,
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4
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Day JD, Park S, Ranard BL, Singh H, Chow CC, Vodovotz Y. Divergent COVID-19 Disease Trajectories Predicted by a DAMP-Centered Immune Network Model. Front Immunol 2021; 12:754127. [PMID: 34777366 PMCID: PMC8582279 DOI: 10.3389/fimmu.2021.754127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/04/2021] [Indexed: 01/08/2023] Open
Abstract
COVID-19 presentations range from mild to moderate through severe disease but also manifest with persistent illness or viral recrudescence. We hypothesized that the spectrum of COVID-19 disease manifestations was a consequence of SARS-CoV-2-mediated delay in the pathogen-associated molecular pattern (PAMP) response, including dampened type I interferon signaling, thereby shifting the balance of the immune response to be dominated by damage-associated molecular pattern (DAMP) signaling. To test the hypothesis, we constructed a parsimonious mechanistic mathematical model. After calibration of the model for initial viral load and then by varying a few key parameters, we show that the core model generates four distinct viral load, immune response and associated disease trajectories termed “patient archetypes”, whose temporal dynamics are reflected in clinical data from hospitalized COVID-19 patients. The model also accounts for responses to corticosteroid therapy and predicts that vaccine-induced neutralizing antibodies and cellular memory will be protective, including from severe COVID-19 disease. This generalizable modeling framework could be used to analyze protective and pathogenic immune responses to diverse viral infections.
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Affiliation(s)
- Judy D Day
- Department of Mathematics, University of Tennessee, Knoxville, TN, United States.,Department of Electrical Engineering & Computer Science, University of Tennessee, Knoxville, TN, United States
| | - Soojin Park
- Department of Neurology & Division of Critical Care and Hospital Neurology, Columbia University College of Physicians and Surgeons, New York Presbyterian Hospital - Columbia University Irving Medical Center, New York, NY, United States.,Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, United States
| | - Benjamin L Ranard
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, United States.,Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Columbia University College of Physicians and Surgeons, New York Presbyterian Hospital - Columbia University Irving Medical Center, New York, NY, United States
| | - Harinder Singh
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Carson C Chow
- Mathematical Biology Section, Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States
| | - Yoram Vodovotz
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Inflammation and Regeneration Modeling, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
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5
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Muncey AR, Patel SY, Whelan CJ, Ackerman RS, Gatenby RA. The Intersection of Regional Anesthesia and Cancer Progression: A Theoretical Framework. Cancer Control 2021; 27:1073274820965575. [PMID: 33070618 PMCID: PMC7791454 DOI: 10.1177/1073274820965575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The surgical stress and inflammatory response and volatile anesthetic
agents have been shown to promote tumor metastasis in animal and
in-vitro studies. Regional neuraxial anesthesia protects against these
effects by decreasing the surgical stress and inflammatory response
and associated changes in immune function in animals. However,
evidence of a similar effect in humans remains equivocal due to the
high variability and retrospective nature of clinical studies and
difficulty in directly comparing regional versus general anesthesia in
humans. We propose a theoretical framework to address the question of
regional anesthesia as protective against metastasis. This theoretical construct views the immune system, circulating tumor
cells, micrometastases, and inflammatory mediators as distinct
populations in a highly connected system. In ecological theory, highly
connected populations demonstrate more resilience to local
perturbations but are prone to system-wide shifts compared with their
poorly connected counterparts. Neuraxial anesthesia transforms the
otherwise system-wide perturbations of the surgical stress and
inflammatory response and volatile anesthesia into a comparatively
local perturbation to which the system is more resilient. We propose
this framework for experimental and mathematical models to help
determine the impact of anesthetic choice on recurrence and metastasis
and create therapeutic strategies to improve cancer outcomes after
surgery.
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6
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Aral AM, Zamora R, Barclay D, Yin J, El-Dehaibi F, Erbas VE, Dong L, Zhang Z, Sahin H, Gorantla VS, Vodovotz Y. The Effects of Tacrolimus on Tissue-Specific, Protein-Level Inflammatory Networks in Vascularized Composite Allotransplantation. Front Immunol 2021; 12:591154. [PMID: 34017323 PMCID: PMC8129572 DOI: 10.3389/fimmu.2021.591154] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 04/14/2021] [Indexed: 12/26/2022] Open
Abstract
Systems-level insights into inflammatory events after vascularized composite allotransplantation (VCA) are critical to the success of immunomodulatory strategies of these complex procedures. To date, the effects of tacrolimus (TAC) immunosuppression on inflammatory networks in VCA, such as in acute rejection (AR), have not been investigated. We used a systems biology approach to elucidate the effects of tacrolimus on dynamic networks and principal drivers of systemic inflammation in the context of dynamic tissue-specific immune responses following VCA. Lewis (LEW) rat recipients received orthotopic hind limb VCA from fully major histocompatibility complex-mismatched Brown Norway (BN) donors or matched LEW donors. Group 1 (syngeneic controls) received LEW limbs without TAC, and Group 2 (treatment group) received BN limbs with TAC. Time-dependent changes in 27 inflammatory mediators were analyzed in skin, muscle, and peripheral blood using Principal Component Analysis (PCA), Dynamic Bayesian Network (DyBN) inference, and Dynamic Network Analysis (DyNA) to define principal characteristics, central nodes, and putative feedback structures of systemic inflammation. Analyses were repeated on skin + muscle data to construct a "Virtual VCA", and in skin + muscle + peripheral blood data to construct a "Virtual Animal." PCA, DyBN, and DyNA results from individual tissues suggested important roles for leptin, VEGF, various chemokines, the NLRP3 inflammasome (IL-1β, IL-18), and IL-6 after TAC treatment. The chemokines MCP-1, MIP-1α; and IP-10 were associated with AR in controls. Statistical analysis suggested that 24/27 inflammatory mediators were altered significantly between control and TAC-treated rats in peripheral blood, skin, and/or muscle over time. "Virtual VCA" and "Virtual Animal" analyses implicated the skin as a key control point of dynamic inflammatory networks, whose connectivity/complexity over time exhibited a U-shaped trajectory and was mirrored in the systemic circulation. Our study defines the effects of TAC on complex spatiotemporal evolution of dynamic inflammation networks in VCA. We also demonstrate the potential utility of computational analyses to elucidate nonlinear, cross-tissue interactions. These approaches may help define precision medicine approaches to better personalize TAC immunosuppression in VCA recipients.
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Affiliation(s)
- Ali Mubin Aral
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Ruben Zamora
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Inflammation and Regenerative Modeling, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Derek Barclay
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jinling Yin
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Fayten El-Dehaibi
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Vasil E Erbas
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medicalpark Gaziantep Hospital, Gaziantep, Turkey
| | - Liwei Dong
- Plastic and Aesthetic Surgery Department, XiJing Hospital, Xi'an, China
| | - Zhaoxiang Zhang
- Plastic and Aesthetic Surgery Department, XiJing Hospital, Xi'an, China
| | | | - Vijay S Gorantla
- Department of Surgery, Wake Forest Institute for Regenerative Medicine, Wake Forest Baptist Medical Center, Winston Salem, NC, United States
| | - Yoram Vodovotz
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Inflammation and Regenerative Modeling, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
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7
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Fribourg M. A case for the reuse and adaptation of mechanistic computational models to study transplant immunology. Am J Transplant 2020; 20:355-361. [PMID: 31562790 PMCID: PMC6984985 DOI: 10.1111/ajt.15623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 02/06/2023]
Abstract
Computational mechanistic models constitute powerful tools for summarizing our knowledge in quantitative terms, providing mechanistic understanding, and generating new hypotheses. The present review emphasizes the advantages of reusing publicly available computational models as a way to capitalize on existing knowledge, reduce the number of parameters that need to be adjusted to experimental data, and facilitate hypothesis generation. Finally, it includes a step-by-step example of the reuse and adaptation of an existing model of immune responses to tuberculosis, tumor growth, and blood pathogens, to study donor-specific antibody (DSA) responses. This review aims to illustrate the benefit of leveraging the currently available computational models in immunology to accelerate the study of alloimmune responses, and to encourage modelers to share their models to further advance our understanding of transplant immunology.
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Affiliation(s)
- Miguel Fribourg
- Translational Transplant Research Center, Department of Medicine, and Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
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8
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Lin L, Xu H, Bishawi M, Feng F, Samy K, Truskey G, Barbas AS, Kirk AD, Brennan TV. Circulating mitochondria in organ donors promote allograft rejection. Am J Transplant 2019; 19:1917-1929. [PMID: 30761731 PMCID: PMC6591073 DOI: 10.1111/ajt.15309] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 01/13/2019] [Accepted: 02/03/2019] [Indexed: 01/25/2023]
Abstract
The innate immune system is a critical regulator of the adaptive immune responses that lead to allograft rejection. It is increasingly recognized that endogenous molecules released from tissue injury and cell death are potent activators of innate immunity. Mitochondria, ancestrally related to bacteria, possess an array of endogenous innate immune-activating molecules. We have recently demonstrated that extracellular mitochondria are abundant in the circulation of deceased organ donors and that their presence correlates with early allograft dysfunction. Here we demonstrate the ability of mitochondria to activate endothelial cells (ECs), the initial barrier between a solid organ allograft and its host. We find that mitochondria exposure leads to the upregulation of EC adhesion molecules and their production of inflammatory cytokines and chemokines. Additionally, mitochondrial exposure causes dendritic cells to upregulate costimulatory molecules. Infusion of isolated mitochondria into heart donors leads to significant increase in allograft rejection in a murine heterotopic heart transplantation model. Finally, co-incubation of human peripheral blood mononuclear cells with mitochondria-treated ECs results in increased numbers of effector (IFN-γ+ , TNF-α+ ) CD8+ T cells. These data indicate that circulating extracellular mitochondria in deceased organ donors may directly activate allograft ECs and promote graft rejection in transplant recipients.
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Affiliation(s)
- Liwen Lin
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina
| | - He Xu
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Muath Bishawi
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina,Biomedical Engineering, Duke University Medical Center, Durham, North Carolina
| | - FeiFei Feng
- Department of Toxicology, Zhengzhou University, Zhengzhou, China
| | - Kannan Samy
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina
| | - George Truskey
- Biomedical Engineering, Duke University Medical Center, Durham, North Carolina
| | - Andrew S Barbas
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Allan D Kirk
- Departments of Surgery, Duke University Medical Center, Durham, North Carolina,Immunology, Duke University Medical Center, Durham, North Carolina
| | - Todd V Brennan
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California
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9
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Bara O, Fliess M, Join C, Day J, Djouadi SM. Toward a model-free feedback control synthesis for treating acute inflammation. J Theor Biol 2018; 448:26-37. [PMID: 29625206 DOI: 10.1016/j.jtbi.2018.04.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 03/03/2018] [Accepted: 04/02/2018] [Indexed: 01/22/2023]
Abstract
An effective and patient-specific feedback control synthesis for inflammation resolution is still an ongoing research area. A strategy consisting of manipulating a pro and anti-inflammatory mediator is considered here as used in some promising model-based control studies. These earlier studies, unfortunately, suffer from the difficultly of calibration due to the heterogeneity of individual patient responses even under similar initial conditions. We exploit a new model-free control approach and its corresponding "intelligent" controllers for this biomedical problem. A crucial feature of the proposed control problem is as follows: the two most important outputs which must be driven to their respective desired states are sensorless. This difficulty is overcome by assigning suitable reference trajectories to the other two outputs that do have sensors. A mathematical model, via a system of ordinary differential equations, is nevertheless employed as a "virtual" patient for in silico testing. We display several simulation results with respect to the most varied situations, which highlight the effectiveness of our viewpoint.
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Affiliation(s)
- Ouassim Bara
- Department of Electrical Engineering and Computer Science University of Tennessee, Knoxville, TN 37996, USA.
| | - Michel Fliess
- LIX (CNRS, UMR 7161), École polytechnique, Palaiseau 91128, France; AL.I.E.N. (ALgèbre pour Identification & Estimation Numériques) 7 rue Maurice Barrès, Vézelise 54330, France.
| | - Cédric Join
- CRAN (CNRS, UMR 7039), Université de Lorraine BP 239, Vandœuvre-lès-Nancy 54506, France; Projet NON-A, INRIA Lille - Nord-Europe, France; AL.I.E.N. (ALgèbre pour Identification & Estimation Numériques) 7 rue Maurice Barrès, Vézelise 54330, France.
| | - Judy Day
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA.
| | - Seddik M Djouadi
- Department of Electrical Engineering and Computer Science University of Tennessee, Knoxville, TN 37996, USA.
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10
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Sud V, Abboud A, Tohme S, Vodovotz Y, Simmons RL, Tsung A. IL-17A - A regulator in acute inflammation: Insights from in vitro, in vivo and in silico studies. Cytokine 2018; 139:154344. [PMID: 29954675 DOI: 10.1016/j.cyto.2018.03.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/18/2018] [Accepted: 03/19/2018] [Indexed: 12/23/2022]
Abstract
Acute inflammation following sterile injury is both inevitable and necessary to restore homeostasis and promote tissue repair. However, when excessive, inflammation can jeopardize the viability of organs and cause detrimental systemic effects. Identifying key-regulators of the immune cascade induced by surgery is vital to attenuating excessive inflammation and its subsequent effects. In this review, we describe the emerging role of IL-17A as a key-regulator in acute inflammation. The role of IL-17A in chronic disease states, such as rheumatoid arthritis, psoriasis and cancer has been well documented, but its significance in acute inflammation following surgery, sepsis, or traumatic injury has not been well studied. We aim to highlight the role of IL-17A in acute inflammation caused by trauma, liver ischemia, and organ transplantation, as well as in post-operative surgical infections. Further investigation of the roles of this cytokine in acute inflammation may stimulate novel therapies or diagnostic modalities.
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Affiliation(s)
- Vikas Sud
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Andrew Abboud
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Samer Tohme
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Yoram Vodovotz
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States; Center for Inflammation and Regenerative Modeling, McGowan Institute for Regenerative Medicine, Pittsburgh, PA, United States
| | - Richard L Simmons
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Allan Tsung
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.
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11
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Dimitrova E, Caromile LA, Laubenbacher R, Shapiro LH. The innate immune response to ischemic injury: a multiscale modeling perspective. BMC SYSTEMS BIOLOGY 2018; 12:50. [PMID: 29631571 PMCID: PMC5891907 DOI: 10.1186/s12918-018-0580-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 03/28/2018] [Indexed: 12/13/2022]
Abstract
Background Cell death as a result of ischemic injury triggers powerful mechanisms regulated by germline-encoded Pattern Recognition Receptors (PRRs) with shared specificity that recognize invading pathogens and endogenous ligands released from dying cells, and as such are essential to human health. Alternatively, dysregulation of these mechanisms contributes to extreme inflammation, deleterious tissue damage and impaired healing in various diseases. The Toll-like receptors (TLRs) are a prototypical family of PRRs that may be powerful anti-inflammatory targets if agents can be designed that antagonize their harmful effects while preserving host defense functions. This requires an understanding of the complex interactions and consequences of targeting the TLR-mediated pathways as well as technologies to analyze and interpret these, which will then allow the simulation of perturbations targeting specific pathway components, predict potential outcomes and identify safe and effective therapeutic targets. Results We constructed a multiscale mathematical model that spans the tissue and intracellular scales, and captures the consequences of targeting various regulatory components of injury-induced TLR4 signal transduction on potential pro-inflammatory or pro-healing outcomes. We applied known interactions to simulate how inactivation of specific regulatory nodes affects dynamics in the context of injury and to predict phenotypes of potential therapeutic interventions. We propose rules to link model behavior to qualitative estimates of pro-inflammatory signal activation, macrophage infiltration, production of reactive oxygen species and resolution. We tested the validity of the model by assessing its ability to reproduce published data not used in its construction. Conclusions These studies will enable us to form a conceptual framework focusing on TLR4-mediated ischemic repair to assess potential molecular targets that can be utilized therapeutically to improve efficacy and safety in treating ischemic/inflammatory injury.
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Affiliation(s)
- Elena Dimitrova
- Department of Mathematical Sciences, Clemson University, Clemson, SC, USA
| | - Leslie A Caromile
- Center for Vascular Biology, Department of Cell Biology, University of Connecticut School of Medicine, Farmington, 06030, CT, USA
| | - Reinhard Laubenbacher
- Center for Quantitative Medicine, Department of Cell Biology, University of Connecticut School of Medicine, Farmington, CT, USA. .,Jackson Laboratory for Genomic Medicine, Farmington, CT, USA.
| | - Linda H Shapiro
- Center for Vascular Biology, Department of Cell Biology, University of Connecticut School of Medicine, Farmington, 06030, CT, USA.
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12
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Arciero JC, Maturo A, Arun A, Oh BC, Brandacher G, Raimondi G. Combining Theoretical and Experimental Techniques to Study Murine Heart Transplant Rejection. Front Immunol 2016; 7:448. [PMID: 27872621 PMCID: PMC5097940 DOI: 10.3389/fimmu.2016.00448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 10/10/2016] [Indexed: 12/21/2022] Open
Abstract
The quality of life of organ transplant recipients is compromised by complications associated with life-long immunosuppression, such as hypertension, diabetes, opportunistic infections, and cancer. Moreover, the absence of established tolerance to the transplanted tissues causes limited long-term graft survival rates. Thus, there is a great medical need to understand the complex immune system interactions that lead to transplant rejection so that novel and effective strategies of intervention that redirect the system toward transplant acceptance (while preserving overall immune competence) can be identified. This study implements a systems biology approach in which an experimentally based mathematical model is used to predict how alterations in the immune response influence the rejection of mouse heart transplants. Five stages of conventional mouse heart transplantation are modeled using a system of 13 ordinary differential equations that tracks populations of both innate and adaptive immunity as well as proxies for pro- and anti-inflammatory factors within the graft and a representative draining lymph node. The model correctly reproduces known experimental outcomes, such as indefinite survival of the graft in the absence of CD4+ T cells and quick rejection in the absence of CD8+ T cells. The model predicts that decreasing the translocation rate of effector cells from the lymph node to the graft delays transplant rejection. Increasing the starting number of quiescent regulatory T cells in the model yields a significant but somewhat limited protective effect on graft survival. Surprisingly, the model shows that a delayed appearance of alloreactive T cells has an impact on graft survival that does not correlate linearly with the time delay. This computational model represents one of the first comprehensive approaches toward simulating the many interacting components of the immune system. Despite some limitations, the model provides important suggestions of experimental investigations that could improve the understanding of rejection. Overall, the systems biology approach used here is a first step in predicting treatments and interventions that can induce transplant tolerance while preserving the capacity of the immune system to protect against legitimate pathogens.
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Affiliation(s)
- Julia C Arciero
- Department of Mathematical Sciences, Indiana University-Purdue University Indianapolis , Indianapolis, IN , USA
| | - Andrew Maturo
- Department of Mathematical Sciences, Indiana University-Purdue University Indianapolis , Indianapolis, IN , USA
| | - Anirudh Arun
- Vascularized and Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine , Baltimore, MD , USA
| | - Byoung Chol Oh
- Vascularized and Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine , Baltimore, MD , USA
| | - Gerald Brandacher
- Vascularized and Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine , Baltimore, MD , USA
| | - Giorgio Raimondi
- Vascularized and Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine , Baltimore, MD , USA
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