TSP1 Secr Sec eted eted b m byy m n a y n y ce c ll cee s Upregulated by injury/stress W dely expressed CD47 S TSP1 only known ligand

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1 Parenchymal CD47 Promotes Renal IRI via Multiple Mechanisms Jeffrey S. Isenberg, MD, MPH Division of Pulmonary, Allergy and Critical Care Medicine Vascular Medicine Institute University of Pittsburgh School of Medicine

2 Conflict of Interest J.S.I. is Chair of the SABs for, and has equity interests in, Vasculox, Inc. and Radiation Control Technologies, Inc.

3 Thrombospondin-1 (TSP1) and CD47 TSP1 Secreted eted by many cells Widely expressed Ser 64 TSP1 only known ligand CD47 S S Upregulated by injury/stress Inhibits cell survival Promotes cell death pathways

4 NO-mediates autocrine and paracrine responses in vascular and inflammatory cells Anti-inflammatoryinflammatory NO Inhibits platelet aggregation VEGF + NO Angiogenesis, permeability enos NO NO enos Vasorelaxation NO NO Isenberg et al, Nature Cancer Reviews,, 2009

5 TSP1 interaction with CD47 redundantly inhibits VEGFR2 and NO/cGMP signaling g VEGF v v Thrombospondin-1 VEGFR2 CD47 ACh M1 AChR Kaur et al, JBC 2011 Gq PI3K PLCγ PDK1 Akt survival Isenberg et al, Cardiovasc Res 2010 CaM enos Hsp90 [Ca 2+ ] Isenberg et al, PNAS 2005 Isenberg et al, JBC 2006 Isenberg et al, Blood 2007 NO sgc cgmp PKG growth, migration, permeability Adapted from Isenberg et al, Nature Reviews Cancer, 2009

6 Renal Ischemia Reperfusion an important cause of acute organ injury dual mechanism of injury Sham kidney Ischemic kidney ischemia: hypoxic cell death reperfusion: ROS & cytokine production, leukocyte infiltration IRI in transplantation promotes delayed clamp graft function & poorer graft outcomes (Hetzel et al. 2002) increases graft immunogenicity & rejection (Halloran et al. 1997) Nothing known about TSP1-CD47 in renal IRI

7 TSP1 and CD47 are increased in renal IRI Rogers et al, J Amer Society Nephrology,, 2012

8 Renal tubular epithelial cells express CD47 and upregulate TSP1 in response to hypoxia RTEC CD47 DAPI FiO 2 1% for 30 min Cells analyzed after 24h reoxygenation N H TSP1 β actin Isotype control CD47 β actin Mean + SD n=4 Rogers et al, J Amer Society Nephrology,, 2012

9 CD47 promotes death from renal IRI Pe ercent survi ival WT IRI (n=5) CD47 -/- IRI (n=7) 40 Absence of activated CD47 confers survival to fatal renal IRI Hours Rogers et al, Am J Physio-Renal,, 2012

10 Activated CD47 impairs blood flow following IRI WT Basal 24h Ischemia reperfusion blood flow CD47 -/- 24h Basal Ischemia reperfusion blood flow Rogers et al, J Amer Society Nephrology,, 2012

11 Activated CD47 promotes histologic and functional damage following renal IRI WT IRI 24h reperfusion CD47 -/ - IRI 24h reperfusion magnification x400 Rogers et al, J Amer Society Nephrology,, 2012

12 Absent CD47 reduces inflammation in renal IRI WT IRI 24h reperfusion CD47 -/ - IRI 24h reperfusion original magnification x200 Rogers et al, J Amer Society Nephrology,, 2012

13 CD47 promotes IRI-associated cell death and apoptosis WT IRI 24h reperfusion CD47 -/ - IRI 24h reperfusion Rogers et al, J Amer Society Nephrology,, 2012

14 CD47 stimulates reactive oxygen species (ROS) production post renal reperfusion WT IRI 24h reperfusion CD47 -/ - IRI 24h reperfusion

15 CD47 upregulates inos to promote renal IRI-mediated ROS production Rogers et al, unpublished

16 CD47 blockade inhibits IRI mediated inos induction in vitro and in vivo Rogers et al, unpublished

17 Parenchymal cell CD47 promotes renal IRI SSC CD47 Kidney function Histologic damage WTBM WT WTBM CD47-/- 100% mortality at 48h 100% survival at 7 days Rogers et al, J Amer Society Nephrology,, 2012

18 Blockade of CD47 abrogates renal IRI CD47 mab given 90mins prior to renal IRI - renal function and histology assessed at 24h reperfusion Kidney function Histologic damage Rogers et al, J Amer Society Nephrology,, 2012

19 Blocking CD47 activation post I/R injury is tissue protective control Ab CD47 Ab Dorsal deep epigastric artery POD 0 flap POD 3 6 cm 2cm femoral artery and vein with take off of epigastric vessels CD47 blocking Ab given 2 hours post reperfusion Maxhimer et al, Plastic and Reconstructive Surgery,, 2009

20 Renal IRI activates parenchymal CD47 to induce inos mediated ROS and tissue injury Health TSP1 Renal IRI CD47 Cell membrane CD47 (activated) Renal TEC parenchymal CD47 is expressed but not activated??? inos O 2 Renal IRI upregulates TSP1 TSP1 binds cell surface CD47 on renal TEC A ti t d CD47 i d inos Activated CD47 induces inosbased superoxide production Protein modifications RTEC apoptosis Renal failure

21 Thank you Isenberg Lab University it of Pittsburgh National Institutes t of Health Molly Yao Natasha Rogers Xiaojun Huang Maryam Sharifi Johannes Kutten Enrico Novelli Dan Dempe Grant support: K22 CA R01 HL AHA 11BGIA P01HL A101A1 2R01HL Australian NHMRC Fellowship Patrick Pagano Michael Bauer Eileen Bauer Gabor Csanyi Mark Gladwin Hunter Champion Joseph Pilewski Yan Qin Thomas Miller David Wink Lisa Ridnour Dave Roberts Justin Maxhimer David Soto-Pantoja Angus Thomson Sukhbir Kaur Academia Deane Mosher Bill Frazier Maria Calzada Joanne Murphy-Ulrich William Monfort

22 Absence of activated CD47 results in accelerated restoration of renal function post-iri ** * *** WT Sham CD47-/- Sham WT IRI 24h CD47-/- IRI 24h WT IRI 72h CD47-/- IRI 72h WT IRI 168h CD47-/- IRI 168h Serum urea (mg/dl) * ** *** Serum creatin nine (mg/dl) WT Sham CD47 Sham -/- WT IRI 24h CD47-/- IRI 24h WT IRI 72h -/- CD47 IRI 72h WT IRI 168h -/- CD47 IRI 168h Rogers et al, unpublished

23 Parenchymal CD47 is a global cell regulator Thrombospondin-1 CD47? Other TSP1 receptors NO/cGMP signaling Other signaling pathways Pathological Physiological (elevated TSP1) angiogenesis tissue perfusion blood pressure hemostasis mitochondria acute ischemia ischemia/reperfusion chronic diseases of aging g Adaptive responses to stress innate immunity adaptive immunity cell motility cell survival radioresistance