Relatore: ANTONIO CURTI

Transcription

1 Relatore: ANTONIO CURTI Posizione di dipendente in aziende con interessi commerciali in campo sanitario (NIENTE DA DICHIARARE) Consulenza ad aziende con interessi commerciali in campo sanitario (NIENTE DA DICHIARARE) Fondi per la ricerca da aziende con interessi commerciali in campo sanitario (NIENTE DA DICHIARARE) Partecipazione ad Advisory Board (NIENTE DA DICHIARARE) Titolarietà di brevetti in compartecipazione ad aziende con interessi commerciali in campo sanitario (NIENTE DA DICHIARARE) Partecipazioni azionarie in aziende con interessi commerciali in campo sanitario (NIENTE DA DICHIARARE) Altro

2 XIII Congresso Nazionale SIES Rimini, OTTOBRE 2014 Circuiti infiammatori e immunoregolatori nel microambiente midollare Antonio Cur* Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale Istituto di Ematologia L. e A. Seràgnoli, Università degli Studi di Bologna

3 HSCs and BM niche: The end of a «splendid isolation» Pro-inflammatory Factors/Alarmins TNFα Interferons Extracellular NTPs TLR ligands

4 HSPC response to Inflammatory Cytokines HSCs do not only respond to the depletion of PB cells: the HSC compartment can react directly to inflammatory cytokines IFNs directly stimulate dormant HSCs and induce active proliferation Essers MAG et al. Nature 2009 Trumpp A. et al., Nat Rev Immunol 2010

5 HSPCs respond to Alarmins HSCs respond directly to stress- and pathogen-related molecules, sensing damage even before inflammatory cytokines are released

6 PRRs: Pathogen Related Receptors PAMPs, DAMPs, and Alarmins P2Rs TLRs RIG-I-like Receptors NOD-like Receptors AIM2-like Receptors Mostly expressed by immune cells (Monocytes, Macrophages, Neutrophils, and DCs)

7 Hematopoietic Stem Cells (HSCs) The network created by PAMPs, DAMPs, Alarmins, and PRRs transversally affects the whole hematopoietic system, from terminally differentiated cells, up to the compartment of immature HSCs Rossi L. et al. Cell Stem Cell 2012

8 The Purinergic Landscape Lemoli, Blood 2004 Rossi, Blood 2007 Ferrari, Exp Hematol 2011 Salvestrini, Blood 2011 Trabanelli, J Immunol 2012 Rossi, Blood 2012 Ciciarello, Stem Cells and Dev 2013 Rossi, Exp Hemat 2013

9 entps and Inflammation Extracellular nucleotides play a key role in tuning inflammation, danger and tissue damage signals Trabanelli S et al., J Immunol 2012 Rossi L. et al., Blood 2012

10 What role do entps play in the HSC compartment? HSC P2Rs? Differentiation Proliferation Migration

11 P2Rs AND PURINERGIC SIGNALLING: Expression Profile in CD34+ HSPCs P2XRs P2X 1 P2X 2 P2X 3 P2X 4 P2X 5 P2X 6 P2X 7 P2X 7 [Ca ++ ] i ATP P2YRs P2Y 1 P2Y 2 [Ca ++ ] i UTP Lemoli RM et al. Blood 2004; Rossi L et al. Blood 2012

12 UTP expands SRCs in NOD/SCID mice 100 CTR 100 UTP % human CD45 + cells % Human CD45+ cells ,1 0,01 0,001 SRC frequency 1/9, % human CD45 + cells % Human CD45+ cells ,1 0,01 SRC frequency 1/3,666 0, CD34 + cells injected/ mice CD34 + cells injected/ mice Lemoli RM et al. Blood 2004

13 Competitive repopulation assay in NOD/SCID mice % human cells * Homing UTP CTR 0 BM PB * p <.05 Rossi et al.; Blood 2007

14 Gene Expression Profiling in UTP-treated HSPCs A. Cytoskeletal organization B. Cell motility and Rho migration GTPases (GTPase-Rho Signaling signaling pathway) C. Cell Adhesion UTP treatment hinders CXCR4 down-regulation and internalization after CXCL12 binding Rossi et al.; Blood 2007

15 entps inhibit AML cell proliferation CFU-C Fold-change CTR 10 nm CD34+ AML ** * 100 nm * ** 1 um ** 10 um ** *** 100 um ** *** 1 mm AML Normal CD34 + eatp increases CD34+ clonogenic potential, however it inhibits AML-derived CFU-L expansion Salvestrini V et al, Blood 2012

16 entps inhibit AML cell migration Cytosk. proteins Cell Motility Cell Motility Inhibitors GTPase Inhibitors Integrins Adhesion Molecules Salvestrini V et al, Blood 2012

17 Purinergic signaling inhibits AML cell Homing and Engraftment eatp inhibits: > AML cell homing > AML cell engraftment > AML LSC engraftment P2X7R expression after culture in the presence of 1mM ATP Salvestrini V et al. Blood 2012

18 Purinergic signalling in Acute Myeloid Leukemia (AML) Normal HSCs Leukemic stem cells Proliferation Migration Homing Engraftment Potential therapeutic use of entps in hematological malignancies

19 Purinergic signaling in BM-MSCs?

20 BM-Derived MSCs express P2Rs 100 bp P2Y 1 R P2Y 2 R P2Y 4 R P2Y 6 R P2Y 11 R P2Y 12 R P2Y 13 R P2Y 14 R DNA-free 100 bp P2X 1 R P2X 3 R P2X 4 R P2X 5 R P2X 6 R P2X 7 R DNA-free 500 bp semi-quantitative PCR Ferrari D. et al. Exp Hematol 2011

21 Role of purinergic signalling In Human BM-MSCs ATP potentiates hmsc spontaneous migration and chemotactic response to CXCL12. In vivo, pretreatment with ATP increases hmscs BM homing. Moreover, ATP modulates BM-MSC differentiation patterns, promoting osteogenesis and adipogenesis Ferrari D et al. Exp Hemat 2011 Ciciarello M et al., Stem Cells Dev 2013

22 Exp Rev Hematol, 2014 Bone Marrow Immunoregulatory Pathways: the immunosuppressive microenvironment in AML

23 Indoleamine 2,3-dioxygenase (IDO) at the cross-road between inflammation and immunotolerance Indoleamine 2,3-dioxygenase (IDO) catalyzes the conversion of tryptophan into kynurenine IDO1 IDO2 Different cells, such as decidua cells, monocytes, regulatory DCs and mesenchymal stromal cells inhibit T-cell responses through IDO expression A wide variety of human tumors expresses IDO protein, which mediates immune tolerance Institute Seràgnoli, Bologna

24 Dendritic cells induce Tregs by means of both IDO enzymes CTR 1-MT-D 1-MT-L myeloid DC plasmacytoid DC Trabanelli et al, J Immunol, 2014

25 Trabanelli et al, J Immunol, 2014 IDO1 and IDO2 expression is differently regulated by inflammation

26 IDO is expressed and functionally active in AML

27 IDO + AML cells induce Tregs through the conversion of CD25 - into CD25 + CD4 + FOXP3 + T cells A) CD4 + CD25 + B) % cells * CD4 + CD25 - Baseline IDO + AML IDO + AML 1-MT * % Annexin-V + cells h 72 h 96 h medium 1-MT medium 1-MT CD4 + CD25 + CD4 + CD25 - C) CD25 CD4 D) % CD4 + CD p= 0.01 p= 0.03 medium 1-MT CTR IDO + IDO - Curti et al. Blood, 2007; Blood, 2009; Haematologica, 2010

28 Ustun C et al. Blood 2011;118: Tregs in AML: is it time for immunomodulation?

29 Induction of lymphopenia IDO inhibitors Depletion of Tregs IDO IDO Arginase PD-1 Anti-PD1 antibodies ipilimumab Expansion of anti-leukemia effectors T cells Leukemia cells Cytokines/soluble factors Inflammatory mediators (ATP) CTLA-4 Immunomodulatory drugs: Lenalidomide Anti-P2X7 (ATP) molecules Chemotherapy? Exp Rev Hematol, 2014

30 Acknowledgements University of Ferrara Francesco Di Virgilio Elena Adinolfi Sara Gulinelli Dept. Of Medicine European Institute of Oncology, Francesco Bertolini Chair of Hematology, IRST S. Martino, Genoa, Italy Roberto M. Lemoli Institute of Hematology «L. and A. Seràgnoli» University of Bologna Valentina Salvestrini Marilena Ciciarello Darina Ocadlikova Mariangela Lecciso Lara Rossi Dorian Forte University of Modena Sergio Ferrari Rossella Manfredini Ludwig Center for Cancer Research, Lausanne Pedro Romero Sara Trabanelli Lucia Catani Daria Sollazzo Mario Arpinati Francesca Ulbar Gabriella Chirumbolo