Head of the lab: Dr. Ketty Soteriadou, email@example.com, tel: +30-2106478841
The main research activity of the laboratory focuses on the study of the protozoan pathogen Leishmania and leishmaniases, a group of diseases caused by the various species of Leishmania transmitted by sand flies. Leismaniases are characterised by a broad spectrum of clinical manifestations with varying severity. Visceral leishmaniasis (VL, kala-azar) can even cause death if left untreated. The leishmaniases are considered as a major public health problem with great social and economic impact.
In our country approximately 50 VL cases are reported every year. The prevalence in dogs, the local reservoir host, is up to 34% in endemic areas like Attiki. However, it is very difficult to provide realistic estimates since official reporting of cases although obligatory is not systematic.
The World Health Organization emphasizes the need for the development of new non-toxic drugs as well as of an effective vaccine, in order to control the continuously increasing number of cases. Additionally, the development of reliable and sensitive diagnostic tools/ methods for early detection of the parasite is of major importance. In order to contribute to the fight against this major health issue we focus our research on the following projects:
- Determination of pathogen factors playing a key role in parasite cell cycle and infectivity/pathogenicity
- Identification and study of putative drug targets in trypanosomatidae like GSK-3 and the determination of new molecules with antiparasitic activity.
- Development of molecular methods for the diagnosis and typing of Leishmania species for usage in epidemiological studies as well as population genetic analysis of strains isolated in South-Eastern Europe.
1. Determination of pathogen factors playing a key role in parasite cell cycle and infectivity/pathogenicity
In particular, we study molecules playing an important role in the parasite life-cycle and infectivity such as linker histone H1 and the leishmanial Ran protein, which belongs to the Ras superfamily of small GTPases. To this end we either generate transgenic parasites that over-express the protein of interest or parasites, where the gene of interest has been knocked out by homologous recombination. The transgenic parasites are being used in in vivo and in vitro experiments for establishing the role for the proteins under study in parasite infectivity.
By using this approach we have shown that overexpression of Leishmania histone H1 (LeishH1) in Leishmania spp. significantly reduces infectivity in macrophages, assessed in vitro, whereas in vivo parasites that overexpress histone H1 are not infectious. Overexpression of LeishH1 causes a delay in cell-cycle progression and more specifically in the G1à S transition and S phase completion. These parasites also delay to differentiate to the amastigote stage, resulting in not being able to survive within the macrophage environment (Smirlis et al, 2006).
In order to determine molecules that are (post)-translationally controlled by LeishH1 over-expression we are currently analysing the differences in the “proteome” between control (bearing plasmid alone) and parasites over-expressing LeishH1 by 2D electrophoresis followed by mass spectroscopy.
We are also interested in the mechanism regulating the Leishmania histones’ expression. The histone protein levels in metazoans are regulated according to the cell-cycle. The protein SLBP (stem-loop binding protein) is a major factor of this mechanism. SLBP interacts with a stem-loop structure present in the histone transcripts. The regulation of histone expression in Leishmania seems to have some common characteristics with the metazoan mechanism. We have characterized a similar stem-loop structure in the Leishmania histone transcripts, which seems to be involved in the regulation of their expression.
Ran GTPase belongs to the Ras superfamily of monomeric G proteins. In mammalian cells is involved in the regulation of nucleocytoplasmic trafficking, nuclear envelope assembly, mitotic spindle assembly, DNA replication and mitotic checkpoint. RanGTP is a chromatin signal that stimulates spindle assembly. We have characterized the leishmanial Ran and studied its role in the parasitic life-cycle. One of the most interesting findings of this study was the observation that Ran interacts with a linker histone, histone H1, in vitro and that the two proteins co-localize at the parasite nuclear rim. Interaction of Ran with LeishH1 suggests that this association maybe involved in modulation of pathways other than those documented for the metazoan Ran–core histone association (Smirlis et al. 2009).
2. The identification and study of putative drug targets in trypanosomatidae like GSK-3 and the determination of new molecules with antiparasitic activity.
In particular we study the antileishmanial activity of indirubins known to target mammalian cyclin-dependent kinases (CDKs) and/or glycogen synthase kinase (GSK-3). We have thus investigated whether the leishmanial GSK-3 could be a target of indirubins. We have characterized GSK-3 in Leishmania and assessed the role of the drug-targeted kinase in cell-cycle progression and the induction of program cell death (PCD). Interestingly, the leishmanial GSK-3 was identified as the predominant intracellular target of 5-Me-6-BIO (Xingi et al. 2009). The leishmanial GSK-3 is validated as a potential drug target and could be exploited for the development of selective indirubin-based leishmanicidals.
In parallel we are analyzing the potential signalling pathways of trypanosomatid GSK-3 in PCD, cell-cycle control and flagellum morphogenesis by using indirubin-treated parasites and GSK-3 RNAi T.brucei mutants.
We have also studied the antileishmanial activity of the taxoid 10-deacetylbaccatin III, isolated from dried needles and small branches of the European yew tree (Taxus baccata). Interestingly 10-deacetylbaccatin III was found to selectively inhibit the growth of L. donovani intracellular amastigotes within J774 murine macrophages in vitro at nanomolar concentrations.
The susceptibility of clinical isolates to first-line drugs used for treating leishmaniasis is also within our research interests.
3. Development of molecular methods for diagnosis and typing of Leishmania species to be used in epidemiological studies as well as in population genetic analysis of strains isolated in South-Eastern Europe.
Even though Leishmaniasis is endemic in Greece, studies dealing with its epidemiology are limited. L. tropica is the species responsible for cutaneous leishmaniases in Greece and L. infantum is the causative agent of visceral leishmaniasis. Besides the predominant MON-1 zymodeme, typing of isolates from human and canine host from Athens and Crete, with the use of Multilocus Enzyme Electrophoresis (MLEE), considered as the gold standard for typing Leishmania, revealed a high percentage of MON-98 (29.3%) which is the highest percentage reported worldwide.
Typing and population structure analysis of isolates is carried out using molecular methods with high discriminatory power. In particular, we have developed a typing method which is based on the amplification of the K26 gene and the subsequent differentiation of the strains based on the size/sequence polymorphism of the gene. The K26-PCR based assay is specific for the Leishmania donovani complex and discriminates L.donovani / L infantum zymodemes. Analysis of the population structure and dynamics of the isolates is carried out by multilocus microsatellite typing (MLMT) using a set of 14 microsatellite markers which are polymorphic within MON-1 strains.
Head of the laboratory
Κetty Soteriadou, Emeritus Research Director; firstname.lastname@example.org
Despina Smirli, Researcher D; email@example.com
Alexandros Alexandratos, firstname.lastname@example.org
Evi Gouzelou, email@example.com
Antonia Estathiou, firstname.lastname@example.org
- GSRT-TUBITAK grant (Joint Research and Technology Programmes 2010-2012, Greece -Turkey). Project title: L. donovani si (re-)emergence and spreading in Europe: Molecular typing, population genetic analysis and risk assessment. Project Leaders: Dr. Ketty Soteriadou (Laboratory of Molecular Parasitology, Hellenic Pasteur Institute, Athens, Greece) and Prof. Seray Ozensoy Toz (Department of Parasitology, Ege University Medical School, Izmir, Turkey). Duration: 2010-2012; Funding: 15,000 €
- International Research Staff Exchange Scheme Call: FP7-PEOPLE-2010-IRSES. Project Title: Exploring the Chemical Biodiversity with Innovative Approaches to Fight Chagas Disease and Leishmaniasis. Project Coordinator: A. L. Skaltsounis, National and Kapodistrian University of Athens. ScientificDirector: Ketty Soteriadou, Hellenic Pasteur Institute. Duration: 2011-2015; Funding: 48,300 €
- SYNERGASIA. Project Title: Investigation of new markers for diagnosing antiplatelet resistance in patients with cardiovascular disease. Alternative therapeutic approaches to the development of new antiplatelet agents. Coordinator: A. Tselepis, University of Ioannina. ScientificDirector HPI: Ketty Soteriadou, Hellenic Pasteur Institute. Duration: 2012-2015; Funding: 150,000 €
- Foundation for Education and European Culture. ProjectTitle: Evaluation of L. donovani growth inhibition by indirubin analogues. Project Coordinator: Dr. Despoina Smirlis. Duration: 2011-2012; Funding: 3,000 €
- EU Key action 2 QLRT-2000-01810: Leishmania genotyping.
- Greek General Secretariat of Research and Technology Programme PENED 2001. Development of Immunochemical methods for isolating taxol derivates from plant sources.
- Greek General Secretariat of Research and Technology Programme EPAN 2003: A novel anti-platelet therapeutic approach in acute coronary syndromes: Combined peptide inhibitors of the platelet integrin αIIb/β3-mediated signaling for nasal and intravenous administration
- FP6-INCO-MED 2004: Monitoring risk factors of spreading of leishmaniasis around the Mediterranean basin
- ΠΑVΕΤ 2005: Galenica AE.: Development of potent peptide-based inhibitors of platelet aggregation.
- ΠΑVΕΤ 2005: Medicon AE.: Application of molecular strips for the development of selective and specific diagnostic tests.
- KESY 2010: Differentiation and Gene Flow among strains of the Leishmania donovani complex in Eastern Mediterranean
Gouzelou E, Haralambous C, Amro A, Mentis A, Pratlong F, Dedet JP, Votypka J, Volf P, Ozensoy Toz S, Kuhls K, Schönian G, Soteriadou K. (2012). Multilocus Microsatellite Typing (MLMT) of Strains from Turkey and Cyprus Reveals a Novel Monophyletic L. donovani Sensu Lato Group. PLoS Negl Trop Dis. 6(2):e1507.
Soares MB, Silva CV, Bastos TM, Guimarães ET, Figueira CP, Smirlis D, Azevedo WF Jr. (2012). Anti-Trypanosoma cruzi activity of nicotinamide. Acta Trop. 122(2):224-9
Smirlis D, Soteriadou K. (2011). Trypanosomatid apoptosis: ‘Apoptosis’ without the canonical regulators. Virulence. 2(3):253-6
Smirlis D, Duszenko M, Ruiz AJ, Scoulica E, Bastien P, Fasel N, Soteriadou K. (2010). Targeting essential pathways in trypanosomatids gives insights into protozoan mechanisms of cell death. Parasit Vectors. 17;3:107.
Mazeris A, Soteriadou K, Dedet JP, Haralambous C, Tsatsaris A, Moschandreas J, Messaritakis I, Christodoulou V, Papadopoulos B, Ivovic V, Pratlong F, Loucaides F, Antoniou M (2010). Leishmaniases and the Cyprus paradox. Am J Trop Med Hyg. 82, 441-448.
D. Smirlis., H. Boleti, M. Gaitanou, M. Soto, K. Soteriadou K (2009). Leishmania donovani RAN-GTPase interacts at the nuclear rim with linker histone H1. Biochem J. 424(3):367-74
D.R. Abanades, L. Ramírez, S. Iborra, K. Soteriadou, V.M. González, P. Bonay, C. Alonso, M. Soto (2009). Key role of the 3′ untranslated region in the cell cycle regulated expression of the Leishmania infantum histone H2A genes: minor synergistic effect of the 5′ untranslated region. BMC Mol Biol. 10, 48.
E. Xingi, D. Smirlis, V. Myrianthopoulos, P. Magiatis, K. Grant, L. Meijer, E. Mikros, AL Skaltsounis, Ketty Soteriadou (2009). 5-Me-6-BIO targeting the leishmanial GSK-3 short form affects cell-cycle progression and induces apoptosis-like death: exploitation of GSK-3 for treating leishmaniasis. Int. J. Paras. 39(12):1289-303
M.Z. Alam, C. Haralambous, K. Kuhls, E. Gouzelou, D. Sgouras, K. Soteriadou, L. Schnur, F. Pratlong, G. Schönian (2009). The paraphyletic composition of Leishmania donovani zymodeme MON-37 revealed by multilocus microsatellite typing. Microbes Infect. 11, 707-715.
Μ. Antoniou, C. Haralambous, A. Mazeris, F. Pratlong, J.P Dedet, K. Soteriadou (2009). Leishmania donovani leishmaniasis in Cyprus. Lancet Infect Dis. 9, 76-77
L. Gradoni,K. Soteriadou, H. Louizir, A. Dakkak, S. Ozensoy, C. Jaffe, J.-P. Dedet, L. Campino, C. Canavate, J-C Dujardin (2008). Drug regimens for visceral leishmaniasis in Mediterranean countries. Trop Med Int Health 13, 1272-1276. Epub 2008 Aug 24.
K. Kuhls, C. Chicharro, C. Cañavate, S. Cortes, L. Campino, C. Haralambous, K. Soteriadou, F. Pratlong, J.P. Dedet, I. Mauricio, M. Miles, M. Schaar, S. Ochsenreither, O.A. Radtke, G. Schönian. (2008). Differentiation and Gene Flow among European Populations of Leishmania infantum MON-1. PLoS Negl Trop Dis. 2(7):e261.
J.C. Dujardin, L. Campino, C. Cañavate, J.P. Dedet, L . Gradoni, K. Soteriadou, A. Mazeris, Y\. Ozbel, M. Boelaert (2008). Spread of vector-borne diseases and neglect of Leishmaniasis, Europe. Emerg Infect Dis. 7, 1013-1018
Μ. Antoniou, C. Haralambous, A. Mazeris, F. Pratlong, J.P Dedet, K. Soteriadou (2008). Leishmania donovani leishmaniasis in Cyprus. Lancet Infect Dis. 8(1), 6-7
I. Papageorgiou, H.P. De Koning, K. Soteriadou and G. Diallinas (2007). Kinetic and mutational analysis of the Trypanosoma brucei NBT1 nucleobase transporter expressed in Saccharomyces cerevisiae reveals structural similarities between ENT and MFS transporters. Int. J. Parasitol.38(6):641-53
C. Haralambous, M. Antoniou, F. Pratlong, J.P. Dedet and K. Soteriadou (2007). Development of a molecular assay specific for the Leishmania donovani complex that discriminates L. donovani/L. infantum zymodemes: a useful tool for typing MON-1. Diagn Microbiol Infect Dis.60(1):33-42
J. Lekakis, S. Bisti, E. Tsougos, A. Papathanassiou, N. Dagres, I. Ikonomidis, K. Soteriadou, A.D. Tselepis, J. Goudevenos and D.T. Kremastinos (2007).Platelet glycoprotein IIb HPA-3 polymorphism and acute coronary syndromes. Int J Cardiol. 127(1):46-50
K. Georgopoulou, D. Smirlis, S. Bisti, E. Xingi, L. Skaltsounis and K. Soteriadou (2007). In vitro activity of 10-deacetylbaccatin III against Leishmania donovani promastigotes and intracellular amastigotes. Planta Med 73, 1081-1088.
C. Haralambous, A. Dakkak, F. Pratlong, J.P. Dedet and K. Soteriadou (2007). First detection and genetic typing of Leishmania infantum MON-24 in a dog from the Moroccan Mediterranean coast: genetic diversity of MON-24. Acta Trop 103(1), 69-79.
J. Lukes, IL. Mauricio, G. Schonian, J.C. Dujardin, K. Soteriadou, J.P. Dedet, K. Kuhls, K.W. Tintaya, M. Jirku, E. Chocholova, C. Haralambous, F. Pratlong, M. Obornik, A. Horak, F.J. Ayala, and M.A. Miles (2007). Evolutionary and geographical history of the Leishmania donovani complex with a revision of current taxonomy. Proc Natl Acad Sci U S A 104(22), 9375-9380.
D. Smirlis, S. Bisti, E. Xingi, G. Konidou, M. Thiakaki and K. Soteriadou (2006). Leishmania histone H1 up-regulation delays parasite cell-cycle progression, parasite differentiation and reduces Leishmania infectivity in vivo. Mol. Microbiol. 60(6), 1457-1473
S. Bisti, G. Konidou, J. Boelaert, M. Lebastard and K. Soteriadou (2006). Effective parasite killing in iron loaded BALB/c mice inoculated in the ear dermis with high and low doses of Leishmania major is associated with an increase in oxidative burst: absence of dermal lesions in the model that is closer to natural settings. Microbes and Infection 8, 1464-1472
S. Bisti and K. Soteriadou (2006).. Protective Immunity and Resistance to Re-infection in iron-loaded BALB/c mice inoculated with a low number of Leishmania major metacyclic promastigotes is associated with NF-κB activation. Microbes and Infection 8, 1473-1482
M. Thiakaki, Β. Kolli, K-P Chang and K. Soteriadou (2006). Down-regulation of gp63 level in Leishmania amazonensis promastigotes reduces their infectivity to BALB/c mice. Microbes and Infection 8, 1455-1460
nuclear rim with linker histone H1. Biochem J. 424(3):367-74
I. Papageorgiou, L. Yakob, M. Al Salabi, G. Diallinas, K. Soteriadou and H. de Koning. (2005). Identification of the first pyrimidine nucleobase transporter in Leishmania: similarities with the Trypanosoma brucei U1 transporter and antileishmanial activity of uracil analogues. Parasitology 130, 275-283
M. Thiakaki, I. Rohousova, V. Volfova, P. Volf, K-P Chang and K. Soteriadou (2005). Sand fly specificity of saliva-mediated protective immunity in Leishmania amazonensis-BALB/c mouse model. Microbes and Infection 7, 760-766
JV Mitsios, Tambaki AP, Abatzis M, Biris N, Sakarellos-Daitsiotis M, Sakarellos C, Soteriadou K, Goudevenos J, Elisaf M, Tsoukatos D, Tsikaris V, Tselepis AD (2004). Effect of synthetic peptides corresponding to residues 313-332 of the alphaIIb subunit on platelet activation and fibrinogen binding to alphaIIbbeta3. Eur J Biochem. 271, 855-62
N. Biris, M. Abatzis, J. Mitsios, M. Sakarellos-Daitsiotis, C. Sakarellos, D. Tsoukatos, A. Tselepis, L. Michalis, D. Sideris, G. Konidou, K. Soteriadou and V. Tsikaris (2003) Mapping of the fibrinogen binding domains on αIIb subunit: A study performed on the activated form of platelet αIIbβ3. Eur.J.Biochem. 270,3760 –3767
F. Papageorgiou and K. Soteriadou (2002). Expression of a novel Leishmania gene encoding for an histone H1-like protein in L. major modulates Leishmania infectivity in vitro. Infect. Immun. 70, 6976-6986
J. Boelaert, R. Appelberg, M. Gomes, E. Blasi, R. Mazzolla, J. Grosset, N. Lounis, K. Soteriadou, M. Thiakaki, D. Taramelli, C. Tognazioli (2001). Experimental results on chloroquine and AIDS-opportunists. JAIDS Hum. Retroviruses. 26,300-301
S. Bisti, G. Konidou, F. Papageorgiou, G. Milon, J. Boelartand K. Soteriadou (2000). The outcome of Leishmania major experimental infection in BALB/C mice can be modulated by endogenously delivered iron. Eur. J. Immunol. 30, 3732-3740
M-C. Petit, P. Orlewski, V. Tsikaris, M. Sakarellos-Daitsiotis, C. Sakarellos, A. Tzinia, G. Konidou, K. Soteriadou, M. Marraud and M. T. Cung (1998). Solution structure of the fibronectin-like Leishmania gp63 SRYD-containing sequence in the free and antibody-bound state. Transferred NOE and molecular dynamics studies. Eur. J. Biochem.253, 184-193
K. Soteriadou, A. Tzinia, E. Panou-Pomonis, V. Tsikaris, M. Sakarellos-Daitsiotis, C Sakarellos G. Papoulou and R. Matsas (1996). Antigenicity and conformational analysis of the zinc-binding sites of two Zn++-metalloproteases: Leishmania gp63 and mammalian endopeptidase E-24.11. Biochem. J. 313, 455-466
K. P. Soteriadou, P. Papavassiliou, C. Voyiatzaki and J. Boelaert (1995). Effect of iron chelation on the in vitro growth of Leishmania promastigotes. J. Antimicrob. Chem. 35, 23-29
K. P. Soteriadou, A. K.Τzinia, A. Mamalaki, M. Phelouzat, F. Lawrence and M. Robert-Gero (1994). Expression of the major surface glycoprotein of Leishmania, gp63, in wild-type and sinefungin-resistant promastigotes. Eur. J. Biochem. 223, 61-68.
C. S. Voyiatzaki and K. P. Soteriadou (1992). Identification and isolation of Leishmania Transferrin Receptor. J. Biol. Chem. 267, 9112-9117.
K. P. Soteriadou, M.S. Remoundos, M.C. Katsikas, A.K. Tzinia, V. Tsikaris, C. Sakarellos and S. Tzartos (1992). The Ser-Arg-Tyr-Asp Region of the Major Surface Glycoprotein of Leishmania Antigenically Mimics the Arg-Gly-Asp-Ser Cell Attachment Region of Fibronectin. J. Biol. Chem. 267, 13980-13985.
A. K. Tzinia and K. P. Soteriadou (1991). Substrate-dependent pH optima of gp63 purified from seven strains of Leishmania promastigotes. Mol. Bioch. Parasitol. 47, 83-90.
C. S. Voyiatzaki and K. P. Soteriadou (1990). Evidence of transferrin binding sites on Leishmania promastigotes. J. Biol. Chem. 265, 22380-22385.