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Immunogenic Cell Death, DAMPs and Prothymosin α as a Putative Anticancer Immune Response Biomarker. Cells 2022; 11:cells11091415. [PMID: 35563721 PMCID: PMC9102069 DOI: 10.3390/cells11091415] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/13/2022] [Accepted: 04/13/2022] [Indexed: 12/13/2022] Open
Abstract
The new and increasingly studied concept of immunogenic cell death (ICD) revealed a previously unknown perspective of the various regulated cell death (RCD) modalities, elucidating their immunogenic properties and rendering obsolete the notion that immune stimulation is solely the outcome of necrosis. A distinct characteristic of ICD is the release of danger-associated molecular patterns (DAMPs) by dying and/or dead cells. Thus, several members of the DAMP family, such as the well-characterized heat shock proteins (HSPs) HSP70 and HSP90, the high-mobility group box 1 protein and calreticulin, and the thymic polypeptide prothymosin α (proTα) and its immunoreactive fragment proTα(100–109), are being studied as potential diagnostic tools and/or possible therapeutic agents. Here, we present the basic aspects and mechanisms of both ICD and other immunogenic RCD forms; denote the role of DAMPs in ICD; and further exploit the relevance of human proTα and proTα(100–109) in ICD, highlighting their possible clinical applications. Furthermore, we present the preliminary results of our in vitro studies, which show a direct correlation between the concentration of proTα/proTα(100–109) and the levels of cancer cell apoptosis, induced by anticancer agents and γ-radiation.
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Prothymosin α activates type I collagen to develop a fibrotic placenta in gestational diabetes. Clin Sci (Lond) 2021; 134:2435-2445. [PMID: 32909608 DOI: 10.1042/cs20200147] [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: 02/14/2020] [Revised: 08/28/2020] [Accepted: 09/10/2020] [Indexed: 11/17/2022]
Abstract
High-risk pregnancies, such as pregnancies with gestational diabetes mellitus (GDM), are becoming more common and as such, have become important public health issues worldwide. GDM increases the risks of macrosomia, premature infants, and preeclampsia. Although placental dysfunction, including fibrosis is associated with the development of GDM, factors that link these observations remain unknown. Prothymosin α (ProTα) is expressed in the placenta and is involved in cell proliferation and immunomodulation. It also plays an important role in insulin resistance and fibrosis. However, the role of ProTα in GDM is still unclear. In the present study, we found that fibrosis-related protein expressions, such as type I collagen (Col-1) were significantly increased in the placentae of ProTα transgenic mice. With elevated fibrosis-related protein expressions, placental weights significantly increased in GDM group. In addition, placental and circulating ProTα levels were significantly higher in patients with GDM (n=39), compared with the healthy group (n=102), and were positively correlated with Col-1 expression. Mice with streptozotocin (STZ)-induced GDM had increased ProTα, fasting blood glucose, Col-1, and placental weight, whereas plasma insulin levels were decreased. ProTα overexpression enhanced nuclear factor κB (NFκB) activation to increase fibrosis-related protein expressions in 3A-Sub-E trophoblasts, while treatment with an NFκB inhibitor reversed the effect of ProTα on fibrosis-related protein expressions. We further investigated whether ProTα is regulated by hyperglycemia-induced reactive oxygen species (ROS). In conclusion, ProTα increases the amount of placental connective tissue and thus contributes to the pathogenesis of placental fibrosis in GDM. Therefore, ProTα may be a novel therapeutic target for GDM.
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Klegeris A. Regulation of neuroimmune processes by damage- and resolution-associated molecular patterns. Neural Regen Res 2021; 16:423-429. [PMID: 32985460 PMCID: PMC7996015 DOI: 10.4103/1673-5374.293134] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Sterile inflammatory processes are essential for the maintenance of central nervous system homeostasis, but they also contribute to various neurological disorders, including neurotrauma, stroke, and demyelinating or neurodegenerative diseases. Immune mechanisms in the central nervous system and periphery are regulated by a diverse group of endogenous proteins, which can be broadly divided into the pro-inflammatory damage-associated molecular patterns (DAMPs) and anti-inflammatory resolution-associated molecular patterns (RAMPs), even though there is notable overlap between the DAMP- and RAMP-like activities for some of these molecules. Both groups of molecular patterns were initially described in peripheral immune processes and pathologies; however, it is now evident that at least some, if not all, of these immunomodulators also regulate neuroimmune processes and contribute to neuroinflammation in diverse central nervous system disorders. The review of recent literature demonstrates that studies on DAMPs and RAMPs of the central nervous system still lag behind the much broader research effort focused on their peripheral counterparts. Nevertheless, this review also reveals that over the last five years, significant advances have been made in our understanding of the neuroimmune functions of several well-established DAMPs, including high-mobility group box 1 protein and interleukin 33. Novel neuroimmune functions have been demonstrated for other DAMPs that previously were considered almost exclusively as peripheral immune regulators; they include mitochondrial transcription factor A and cytochrome C. RAMPs of the central nervous system are an emerging area of neuroimmunology with very high translational potential since some of these molecules have already been used in preclinical and clinical studies as candidate therapeutic agents for inflammatory conditions, such as multiple sclerosis and rheumatoid arthritis. The therapeutic potential of DAMP antagonists and neutralizing antibodies in central nervous system neuroinflammatory diseases is also supported by several of the identified studies. It can be concluded that further studies of DAMPs and RAMPs of the central nervous system will continue to be an important and productive field of neuroimmunology.
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Affiliation(s)
- Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC, Canada
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Wenzel TJ, Kwong E, Bajwa E, Klegeris A. Resolution-Associated Molecular Patterns (RAMPs) as Endogenous Regulators of Glia Functions in Neuroinflammatory Disease. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2020; 19:483-494. [DOI: 10.2174/1871527319666200702143719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/17/2020] [Accepted: 04/20/2020] [Indexed: 01/01/2023]
Abstract
Glial cells, including microglia and astrocytes, facilitate the survival and health of all cells
within the Central Nervous System (CNS) by secreting a range of growth factors and contributing to
tissue and synaptic remodeling. Microglia and astrocytes can also secrete cytotoxins in response to
specific stimuli, such as exogenous Pathogen-Associated Molecular Patterns (PAMPs), or endogenous
Damage-Associated Molecular Patterns (DAMPs). Excessive cytotoxic secretions can induce the death
of neurons and contribute to the progression of neurodegenerative disorders, such as Alzheimer’s disease
(AD). The transition between various activation states of glia, which include beneficial and detrimental
modes, is regulated by endogenous molecules that include DAMPs, cytokines, neurotransmitters,
and bioactive lipids, as well as a diverse group of mediators sometimes collectively referred to as
Resolution-Associated Molecular Patterns (RAMPs). RAMPs are released by damaged or dying CNS
cells into the extracellular space where they can induce signals in autocrine and paracrine fashions by
interacting with glial cell receptors. While the complete range of their effects on glia has not been described
yet, it is believed that their overall function is to inhibit adverse CNS inflammatory responses,
facilitate tissue remodeling and cellular debris removal. This article summarizes the available evidence
implicating the following RAMPs in CNS physiological processes and neurodegenerative diseases:
cardiolipin (CL), prothymosin α (ProTα), binding immunoglobulin protein (BiP), heat shock protein
(HSP) 10, HSP 27, and αB-crystallin. Studies on the molecular mechanisms engaged by RAMPs could
identify novel glial targets for development of therapeutic agents that effectively slow down neuroinflammatory
disorders including AD.
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Affiliation(s)
- Tyler J. Wenzel
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Evan Kwong
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Ekta Bajwa
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
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Lunin S, Khrenov M, Glushkova O, Parfenyuk S, Novoselova T, Novoselova E. Precursors of thymic peptides as stress sensors. Expert Opin Biol Ther 2020; 20:1461-1475. [PMID: 32700610 DOI: 10.1080/14712598.2020.1800636] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
INTRODUCTION A large volume of data indicates that the known thymic hormones, thymulin, thymopoietin, thymosin-α, thymosin-β, and thymic humoral factor-y2, exhibit different spectra of activities. Although large in volume, available data are rather fragmented, resulting in a lack of understanding of the role played by thymic hormones in immune homeostasis. AREA COVERED Existing data compartmentalizes the effect of thymic peptides into 2 categories: influence on immune cells and interconnection with neuroendocrine systems. The current study draws attention to a third aspect of the thymic peptide effect that has not been clarified yet, wherein ubiquitous and highly abundant intranuclear precursors of so called 'thymic peptides' play a fundamental role in all somatic cells. EXPERT OPINION Our analysis indicated that, under certain stress-related conditions, these precursors are cleaved to form immunologically active peptides that rapidly leave the nucleus and intracellular spaces, to send 'distress signals' to the immune system, thereby acting as stress sensors. We propose that these peptides may form a link between somatic cells and immune as well as neuroendocrine systems. This model may provide a better understanding of the mechanisms underlying immune homeostasis, leading thereby to the development of new therapeutic regimes utilizing the characteristics of thymic peptides.
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Affiliation(s)
- Sergey Lunin
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
| | - Maxim Khrenov
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
| | - Olga Glushkova
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
| | - Svetlana Parfenyuk
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
| | - Tatyana Novoselova
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
| | - E Novoselova
- Laboratory of Reception Mechanisms, Institute of Cell Biophysics of the Russian Academy of Sciences, PSCBR RAS , Pushchino, Russia
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Birmpilis AI, Karachaliou CE, Samara P, Ioannou K, Selemenakis P, Kostopoulos IV, Kavrochorianou N, Kalbacher H, Livaniou E, Haralambous S, Kotsinas A, Farzaneh F, Trougakos IP, Voelter W, Dimopoulos MA, Bamias A, Tsitsilonis O. Antitumor Reactive T-Cell Responses Are Enhanced In Vivo by DAMP Prothymosin Alpha and Its C-Terminal Decapeptide. Cancers (Basel) 2019; 11:cancers11111764. [PMID: 31717548 PMCID: PMC6896021 DOI: 10.3390/cancers11111764] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022] Open
Abstract
Prothymosin α (proTα) and its C-terminal decapeptide proTα(100-109) were shown to pleiotropically enhance innate and adaptive immune responses. Their activities have been broadly studied in vitro, focusing primarily on the restoration of the deficient immunoreactivity of cancer patients' leukocytes. Previously, we showed that proTα and proTα(100-109) act as danger-associated molecular patterns (DAMPs), ligate Toll-like receptor-4, signal through TRIF- and MyD88-dependent pathways, promote the maturation of dendritic cells and elicit T-helper type 1 (Th1) immune responses in vitro, leading to the optimal priming of tumor antigen-reactive T-cell functions. Herein, we assessed their activity in a preclinical melanoma model. Immunocompetent mice bearing B16.F1 tumors were treated with two cycles of proTα or proTα(100-109) together with a B16.F1-derived peptide vaccine. Coadministration of proTα or proTα(100-109) and the peptide vaccine suppressed melanoma-cell proliferation, as evidenced by reduced tumor-growth rates. Higher melanoma infiltration by CD3+ T cells was observed, whereas ex vivo analysis of mouse total spleen cells verified the in vivo induction of melanoma-reactive cytotoxic responses. Additionally, increased levels of proinflammatory and Th1-type cytokines were detected in mouse serum. We propose that, in the presence of tumor antigens, DAMPs proTα and proTα(100-109) induce Th1-biased immune responses in vivo. Their adjuvant ability to orchestrate antitumor immunoreactivities can eventually be exploited therapeutically in humans.
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Affiliation(s)
- Anastasios I. Birmpilis
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
| | - Chrysoula-Evangelia Karachaliou
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety, NCSR “Demokritos”, Agia Paraskevi, 15310 Athens, Greece; (C.-E.K.); (E.L.)
| | - Pinelopi Samara
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
| | - Kyriaki Ioannou
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
- King’s College London, Rayne Institute, 123 Coldharbour Lane, SE5 9NU London, UK;
| | - Platon Selemenakis
- Molecular Carcinogenesis Group, Department of Histology and Embryology, School of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece; (P.S.); (A.K.)
| | - Ioannis V. Kostopoulos
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
| | - Nadia Kavrochorianou
- Inflammation Research Group, Transgenic Technology Laboratory, Hellenic Pasteur Institute, 127 Vasilissis Sofias Avenue, 11521 Athens, Greece; (N.K.); (S.H.)
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen. Germany; (H.K.); (W.V.)
| | - Evangelia Livaniou
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety, NCSR “Demokritos”, Agia Paraskevi, 15310 Athens, Greece; (C.-E.K.); (E.L.)
| | - Sylva Haralambous
- Inflammation Research Group, Transgenic Technology Laboratory, Hellenic Pasteur Institute, 127 Vasilissis Sofias Avenue, 11521 Athens, Greece; (N.K.); (S.H.)
| | - Athanasios Kotsinas
- Molecular Carcinogenesis Group, Department of Histology and Embryology, School of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece; (P.S.); (A.K.)
| | - Farzin Farzaneh
- King’s College London, Rayne Institute, 123 Coldharbour Lane, SE5 9NU London, UK;
| | - Ioannis P. Trougakos
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen. Germany; (H.K.); (W.V.)
| | - Meletios-Athanasios Dimopoulos
- Department of Clinical Therapeutics, School of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (M.-A.D.); (A.B.)
| | - Aristotelis Bamias
- Department of Clinical Therapeutics, School of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (M.-A.D.); (A.B.)
| | - Ourania Tsitsilonis
- Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.I.B.); (P.S.); (K.I.); (I.V.K.); (I.P.T.)
- Correspondence: ; Tel.: +30-210-727-4215; Fax: +30-210-727-4635
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Samara P, Miriagou V, Zachariadis M, Mavrofrydi O, Promponas VJ, Dedos SG, Papazafiri P, Kalbacher H, Voelter W, Tsitsilonis O. A fragment of the alarmin prothymosin α as a novel biomarker in murine models of bacteria-induced sepsis. Oncotarget 2018; 8:48635-48649. [PMID: 28611290 PMCID: PMC5564713 DOI: 10.18632/oncotarget.18149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/17/2017] [Indexed: 12/21/2022] Open
Abstract
Sepsis is a life-threatening condition that requires urgent care. Thus, the identification of specific and sensitive biomarkers for its early diagnosis and management are of clinical importance. The alarmin prothymosin alpha (proTα) and its decapeptide proTα(100-109) are immunostimulatory peptides related to cell death. In this study, we generated bacterial models of sepsis in mice using two Klebsiella pneumoniae strains (L-78 and ATCC 43816) and monitored sepsis progression using proTα(100-109) as a biomarker. Serum concentration of proTα(100-109) gradually increased as sepsis progressed in mice infected with L-78, a strain which, unlike ATCC 43816, was phagocytosed by monocytes/macrophages. Analysis of splenocytes from L-78-infected animals revealed that post-infection spleen monocytes/macrophages were gradually driven to caspase-3-mediated apoptosis. These results were verified in vitro in L-78-infected human monocytes/macrophages. Efficient phagocytosis of L-78 by monocytes stimulated their apoptosis and the concentration of proTα(100-109) in culture supernatants increased. Human macrophages strongly phagocytosed L-78, but resisted cell death. This is the first report suggesting that high levels of proTα(100-109) correlate, both in vitro and in vivo, with increased percentages of cell apoptosis. Moreover, we showed that low levels of proTα(100-109) early post-infection likely correlate with sepsis resolution and thus, the decapeptide could eventually serve as an early surrogate biomarker for predicting bacteria-induced sepsis outcome.
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Affiliation(s)
- Pinelopi Samara
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Vivi Miriagou
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
| | - Michael Zachariadis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece.,Institute of Biosciences and Applications, National Center for Scientific Research "Demokritos", Agia Paraskevi, Athens, Greece
| | - Olga Mavrofrydi
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Skarlatos G Dedos
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Panagiota Papazafiri
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Ourania Tsitsilonis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
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Karachaliou CE, Triantis C, Liolios C, Palamaris L, Zikos C, Tsitsilonis OE, Kalbacher H, Voelter W, Loudos G, Papadopoulos M, Pirmettis I, Livaniou E. In vivo biodistribution and imaging studies with a 99mTc-radiolabeled derivative of the C-terminus of prothymosin alpha in mice bearing experimentally-induced inflammation. Eur J Pharm Biopharm 2017; 113:188-197. [PMID: 28087377 DOI: 10.1016/j.ejpb.2016.12.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 11/15/2016] [Accepted: 12/14/2016] [Indexed: 10/20/2022]
Abstract
Prothymosin alpha (ProTα) is a highly conserved mammalian polypeptide (109 amino acids in man) exerting in vitro and in vivo immunoenhancing activities. Recently, our team has developed a 99mTc-radiolabeled derivative of the C-terminal bioactive decapeptide of ProTα ([99mTc]C1) and employed it in in vitro studies, the results of which support the existence of binding sites on human neutrophils that recognize [99mTc]C1, intact ProTα as well as the C-terminal decapeptide of ProTα and presumably involve Toll-like receptor 4. In the present work, [99mTc]C1 was administered to Swiss albino mice with experimentally-induced inflammation for in vivo biodistribution and imaging studies, in parallel with a suitable negative control, which differs from [99mTc]C1 only in bearing a scrambled version of the ProTα decapeptide. The biodistribution data obtained with [99mTc]C1 demonstrated fast clearance of radioactivity from blood, heart, lungs, normal muscle, and predominantly urinary excretion. Most importantly, slow clearance of radioactivity from the inflammation focus was observed, resulting in a high ratio of inflamed/normal muscle tissue (9.15 at 30min post injection, which remained practically stable up to 2h). The inflammation-targeting capacity of [99mTc]C1 was confirmed by imaging studies and might be attributed to neutrophils, which are recruited at the inflamed areas and bear binding sites for [99mTc]C1. In this respect, apart from being a valuable tool for further studies on ProTα in in vitro and in vivo systems, [99mTc]C1 merits further evaluation as a radiopharmaceutical for specific imaging of inflammation foci.
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Affiliation(s)
- Chrysoula-Evangelia Karachaliou
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Charalampos Triantis
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Christos Liolios
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Lazaros Palamaris
- Department of Medical Instruments Technology, Technological Educational Institute, Athens 12243, Greece
| | - Christos Zikos
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Ourania E Tsitsilonis
- Division of Animal and Human Physiology, Department of Biology, University of Athens, Athens 15784, Greece
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - George Loudos
- Department of Medical Instruments Technology, Technological Educational Institute, Athens 12243, Greece
| | - Minas Papadopoulos
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Ioannis Pirmettis
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece
| | - Evangelia Livaniou
- Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety (INRASTES), National Center for Scientific Research "Demokritos" (NCSR "Demokritos"), Athens 15310, Greece.
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Papaioannou NE, Voutsas IF, Samara P, Tsitsilonis OE. A flow cytometric approach for studying alterations in the cytoplasmic concentration of calcium ions in immune cells following stimulation with thymic peptides. Cell Immunol 2016; 302:32-40. [DOI: 10.1016/j.cellimm.2016.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/10/2015] [Accepted: 01/06/2016] [Indexed: 11/29/2022]
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Ueda H, Halder SK, Matsunaga H, Sasaki K, Maeda S. Neuroprotective impact of prothymosin alpha-derived hexapeptide against retinal ischemia-reperfusion. Neuroscience 2016; 318:206-18. [PMID: 26779836 DOI: 10.1016/j.neuroscience.2016.01.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 12/17/2015] [Accepted: 01/05/2016] [Indexed: 01/13/2023]
Abstract
Prothymosin alpha (ProTα) has robustness roles against brain and retinal ischemia or serum-starvation stress. In the ProTα sequence, the active core 30-amino acid peptide/P30 (a.a.49-78) is necessary for the original neuroprotective actions against ischemia. Moreover, the 9-amino acid peptide sequence/P9 (a.a.52-60) in P30 still shows neuroprotective activity against brain and retinal ischemia, though P9 is less potent than P30. As the previous structure-activity relationship study for ProTα may not be enough, the possibility still exists that any sequence smaller than P9 retains potent neuroprotective activity. When different P9- and P30-related peptides were intravitreally injected 24h after retinal ischemia in mice, the 6-amino acid peptide/P6 (NEVDEE, a.a.51-56) showed potent protective effects against ischemia-induced retinal functional deficits, which are equipotent to the level of P30 peptide in electroretinography (ERG) and histological damage in Hematoxylin and Eosin (HE) staining. Further studies using ERG and HE staining suggested that intravitreal or intravenous (i.v.) injection with modified P6 peptide/P6Q (NEVDQE) potently inhibited retinal ischemia-induced functional and histological damage. In an immunohistochemical analysis, the ischemia-induced loss of retinal ganglion, bipolar, amacrine and photoreceptor cells were inhibited by a systemic administration with P6Q peptide 24h after the ischemic stress. In addition, systemic post-treatment with P6Q peptide significantly inhibited retinal ischemia-induced microglia and astrocyte activation in terms of increased ionized calcium-binding adaptor molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) intensity, respectively, as well as their morphological changes, increased number and migration. Thus, this study demonstrates the therapeutic significance of modified P6 peptide P6Q (NEVDQE) derived from 6-amino acid peptide (P6) in ProTα against ischemic damage.
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Affiliation(s)
- H Ueda
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521, Japan.
| | - S K Halder
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - H Matsunaga
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - K Sasaki
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - S Maeda
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521, Japan
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Prothymosin Alpha and Immune Responses: Are We Close to Potential Clinical Applications? VITAMINS AND HORMONES 2016; 102:179-207. [PMID: 27450735 PMCID: PMC7126549 DOI: 10.1016/bs.vh.2016.04.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The thymus gland produces soluble molecules, which mediate significant immune functions. The first biologically active thymic extract was thymosin fraction V, the fractionation of which led to the isolation of a series of immunoactive polypeptides, including prothymosin alpha (proTα). ProTα displays a dual role, intracellularly as a survival and proliferation mediator and extracellularly as a biological response modifier. Accordingly, inside the cell, proTα is implicated in crucial intracellular circuits and may serve as a surrogate tumor biomarker, but when found outside the cell, it could be used as a therapeutic agent for treating immune system deficiencies. In fact, proTα possesses pleiotropic adjuvant activity and a series of immunomodulatory effects (eg, anticancer, antiviral, neuroprotective, cardioprotective). Moreover, several reports suggest that the variable activity of proTα might be exerted through different parts of the molecule. We first reported that the main immunoactive region of proTα is the carboxy-terminal decapeptide proTα(100-109). In conjunction with data from others, we also revealed that proTα and proTα(100-109) signal through Toll-like receptor 4. Although their precise molecular mechanism of action is yet not fully elucidated, proTα and proTα(100-109) are viewed as candidate adjuvants for cancer immunotherapy. Here, we present a historical overview on the discovery and isolation of thymosins with emphasis on proTα and data on some immune-related new activities of the polypeptide and smaller immunostimulatory peptides thereof. Finally, we propose a compiled scenario on proTα's mode of action, which could eventually contribute to its clinical application.
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Zhang BC, Sun L. Tongue sole (Cynoglossus semilaevis) prothymosin alpha: Cytokine-like activities associated with the intact protein and the C-terminal region that lead to antiviral immunity via Myd88-dependent and -independent pathways respectively. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 53:96-104. [PMID: 26162512 DOI: 10.1016/j.dci.2015.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 07/01/2015] [Accepted: 07/02/2015] [Indexed: 06/04/2023]
Abstract
Prothymosin alpha (ProTα) is a small protein that in mammals is known to participate in diverse biological processes including immunomodulation. In teleost, the immunological function of ProTα is unknown. In the current study, we investigated the expression and function of the ProTα (named CsProTα) from the teleost fish tongue sole (Cynoglossus semilaevis). We found that CsProTα expression was abundant in immune relevant tissues and upregulated by megalocytivirus infection. Immunoblot detected secretion of CsProTα by peripheral blood leukocytes. Recombinant CsProTα (rCsProTα) as well as the C-terminal 11-residue (Ct11) were able to bind head kidney monocytes (HKM) and induce immune gene expression; however, the induction patterns caused by rCsProTα and Ct11 differed considerably. When introduced in vivo, rCsProTα and Ct11 significantly reduced megalocytivirus infection in fish tissues, whereas rCsProTα antibody significantly promoted viral replication. Blocking of Myd88 activity abolished the virus-inhibitory effect of rCsProTα but not Ct11. Taken together, these results demonstrate for the first time that both the intact protein and the C-terminal segment of a teleost ProTα can act like cytokines and induce antiviral immunity via, however, distinct signaling pathways that differ in the requirement of Myd88.
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Affiliation(s)
- Bao-cun Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Li Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
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Karachaliou CE, Liolios C, Triantis C, Zikos C, Samara P, Tsitsilonis OE, Kalbacher H, Voelter W, Papadopoulos M, Pirmettis I, Livaniou E. Specific in vitro binding of a new (99m)Tc-radiolabeled derivative of the C-terminal decapeptide of prothymosin alpha on human neutrophils. Int J Pharm 2015; 486:1-12. [PMID: 25796124 DOI: 10.1016/j.ijpharm.2015.03.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 11/28/2022]
Abstract
Prothymosin alpha (ProTα) is a conserved mammalian polypeptide with intracellular functions associated with cell proliferation and apoptosis and an extracellular role associated with immunopotentiation. The N-terminal fragment [1-28], which is identical with the immunostimulating peptide thymosin α1 (Tα1), was earlier considered as the immunoactive region of the polypeptide; however, recent data suggest that ProTα may exert a discrete immunomodulating action through its central or C-terminal region, via targeting Toll-like receptor- 4 (TLR4). In this work, a derivative of the C-terminal fragment ProTα[100-109] (ProTα-D1) that can be radiolabeled with (99m)Tc was developed. The biological activity of the non-radioactive (185/187)rhenium-complex of this derivative ([(185/187)Re]ProTα-D1, structurally similar with [(99m)Tc]ProTα-D1) was verified through suitable in vitro bioassays on human neutrophils. Subsequent cell-binding studies revealed specific, time-dependent and saturable binding of [(99m)Tc]ProTα-D1 on neutrophils, which was inhibited by intact ProTα and ProTα[100-109], as well as by a "prototype" TLR4-ligand (lipopolysaccharide from Escherichia coli). Overall, our results support the existence of ProTα-binding sites on human neutrophils, recognizing [(99m)Tc]ProTα-D1, which might involve TLR4. [(99m)Tc]ProTα-D1 may be a useful tool for conducting further in vitro and in vivo studies, aiming to elucidate the extracellular mode of action of ProTα and, eventually, develop ProTα-based immunotherapeutics.
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Affiliation(s)
- Chrysoula-Evangelia Karachaliou
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Christos Liolios
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Charalampos Triantis
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Christos Zikos
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Pinelopi Samara
- Faculty of Biology, University of Athens, Athens 15784, Greece
| | | | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - Minas Papadopoulos
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Ioannis Pirmettis
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Evangelia Livaniou
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece.
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Baxevanis CN, Voutsas IF, Tsitsilonis OE. Toll-like receptor agonists: current status and future perspective on their utility as adjuvants in improving anticancer vaccination strategies. Immunotherapy 2013; 5:497-511. [PMID: 23638745 DOI: 10.2217/imt.13.24] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Toll-like receptor (TLR) agonists possess remarkable properties, particularly with regard to dendritic cell activation, promoting Th1-type cytokine production and optimizing cytotoxic T-cell responses. Preclinical and clinical studies conducted to date show that TLR agonists can improve currently applied anticancer vaccination protocols. Although these have resulted in the US FDA approval of three TLR agonists for use in humans, their abundant application encounters limitations, principally due to dose-limiting toxicity evoking from systemic cytokine production. Here, using selected examples of clinical studies, we provide a concise review regarding the knowledge acquired thus far on the adjuvant use of TLR agonists as cancer vaccine components. We also provide evidence on the exploitation of a novel TLR agonist, prothymosin-α, which enhances the efficacy of tumor-reactive effectors without causing severe adverse effects.
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Development of an ELISA for the quantification of the C-terminal decapeptide prothymosin α(100-109) in sera of mice infected with bacteria. J Immunol Methods 2013; 395:54-62. [PMID: 23831611 DOI: 10.1016/j.jim.2013.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/21/2013] [Accepted: 06/21/2013] [Indexed: 11/20/2022]
Abstract
Apoptosis is characterized by a series of discrete biochemical events, among which is the truncation of the nuclear polypeptide prothymosin alpha (proTα) by activated caspase-3. This early apoptotic event results in the generation of a carboxy-terminal fragment of proTα, the immunoactive decapeptide proTα(100-109). We hypothesized that the detection of increased levels of proTα(100-109) in serum can be directly correlated with the induction of massive cell apoptosis, resulting from a severe bacterial infection. Thus, using high-affinity-purified polyclonal antibodies (Abs), raised in rabbits and a prototype antibody-capture system, we developed a highly sensitive and specific competitive ELISA for proTα(100-109). The sensitivity of the ELISA (0.1ng/mL to 10μg/mL) is acceptable for the quantification of the decapeptide in serum samples. To assess our initial hypothesis, we determined the concentration of proTα(100-109) in the sera of mice infected with the bacterium Streptococcus pyogenes over the course of the infection. We show that serum concentration of proTα(100-109) was marginal to undetectable before infection, increased over time and peaked at 72h postinfection. In silico analysis suggests that the Abs generated are unlikely to cross-react with any other unrelated mouse or bacterial protein. Further validation of our ELISA using serum samples from humans, infected with bacteria, may provide a useful tool to differentiate the causative agent of a potentially lethal septic infection.
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