Zahi A. Fayad, PhDAssociate Professor

Imaging Science Laboratories

Depts of Radiology and MedicineThe Zena and Michael A. Wiener

Cardiovascular Institute and The Marie-Josee and Henry R. Kravis Cardiovascular

Health CenterMount Sinai School of Medicine, New York,

NY

11-12-2005 AEHA - Shape GuidelinesDallas, Tx

Noninvasive Molecular Imaging of AtherosclerosisWith MRI - The Future Lies in Molecular Imaging,

The question is which molecule

Choudhury RP; Fuster V; Fayad ZA Nature Drug Dev. 2004;3:913-925

Atherosclerosis: A Progressive Process

Imaging Science Laboratories

Noninvasive Detection of Plaque Instabilitywith Use of Radiolabeled (SPECT) Annexin A5 in Patients

with Carotid-Artery Atherosclerosis

Kietselaer BLJH et al. NEJM 350;14;April 1, 2004

•Left-Sided TIA 3 days before imaging

•Annexin A5 hot spot•Annexin A5 staining

•Right-sided TIA 3 months before

imagingªNo Annexin hot spot

•No Annexing A5 staining

Davies JR, Rudd JH, Stroke 2005 in press

Plaque Activity Assessment -18F-FDG- Macs

PET/CT or PET/MR

Rudd JHF et al. Circ 2002;105:2708-2711

• Paramagnetic (Iron)• Superparamagnetic (Gd)• Targeted Contrasts/Carriers

Current Contrast-Enhanced MR LimitedPlaque Activity Information

Gd-chelate enhanced-non specific

Targeted enhanced contrast agent - specific interaction with plaque

Choudhury RP; Fuster V; Fayad ZA Nature Drug Dev. 2004

Aorta

IVC

Non specific Targeted

Molecular Imaging Contrast Agents

Choudhury RP; Fuster V; Fayad ZA Nature Drug Dev. 2004Lipinski MJ; Fuster V; Fayad ZA Nature Cardiovascular Medicine 2004

• Improve MR detection sensitivity

• CA w high-relaxivity

- e.g., small peptides

• Increase payload of contrast agent

• Targeted/Functional • Colloidal Carriers/Lipid based

- Liposomes

- microemulsions

- micelles

- lipoproteins

• Targets

Age Characterization Using Fibrin-Targeted MR Contrast Agent in Chronic Thrombus

0

2

4

6

8

10

12

1

* P<0.01

Pre Acute 48 hours 1 week 2 weeks 3 weeks 4 weeks 6 weeks 8 weeks

Con

tras

t to

Noi

se R

atio

(CN

R)

*

*

*

4x

Acute Thrombus

4x

1-week-old Thrombus

10x

8-week-old Thrombus

4x

6-week-old Thrombus

Sirol M; Fayad ZA et al. Atherosclerosis 2005:182:79-85Sirol M; Fayad ZA et al. Circ 2005;112:1594-1600

MATRIX METALLOPROTEINASES TARGETING - Gd-peptide Approach

IHC of atherosclerotic plaque for MMP2

MMP Zymography ofaorta of ApoE mouse

40x

40x

P947 (Guerbet) short peptide MMPs inhibitor100 mol/kg

Amirbekian V; Fayad ZA et al. AHA 2005;D220 @ NOV 15 @ 4:45PM Imaging Science Laboratories

NER P947 vs. P1135

0

0.5

1

1.5

2

2.5

3

1 2 3 4 5

Time-Point (1 = Pre-Contrast; 2 = 1 hr post; 3 = 2 hrs post; 4 = 3 hrs post; 5 = 22 hrs post)

NER

P947 ExternalStandard

P947

control

P1135

Lipid-Based Particulates

Lipoproteins: Chylo, VLDL, TG, LDL, HDL

• Gd, Iron, Fluorescents, etc.• Ab, peptide, etc.

In Vivo Aortic Atherosclerotic Plaque in ApoE-KO MiceGd Immunomicelles Macrophages scavenger receptor types

I&II Murine (CD204)

9.4T TR=500 ms; TE= 8.6 ms101 m in plane spatial resolution500 µm slice thickness

Injected - 13.7µmol/kg

M

A

C

Amirbekian V; Fayad ZA et al.; AHA 2005;Nov 15;D220 @2pm

Imaging Science Laboratories

Sirol M; Fayad ZA et al. Circulation. 2004;109:2890-2896

Sirol M; Fayad ZA et al. AHA 2005 Nov 15 D220 @ 2:45 pm

Atherosclerotic Plaques Detected by Gadofluorine-Enhanced In Vivo MRI

Imaging Science Laboratories

Gadofluorine M Plaque MR ApoE-KO mouse lesions

• Yellow - localization in ECM (tenascin)• No cellular uptake

M

Lymphocytes

Smooth muscle cells

mAb (green)Gadofluorine-carbocyanin conjugate (red)DAPI cell nuclei (blue)

Sirol M; Fayad ZA et al. AHA 2005 NOV 15 D220;4:30PM

9.4T TR=500 ms; TE= 8.6 ms101 m in plane spatial resolution500 µm slice thickness100µmol/Kg (gadofluorine M)

Kelly KA, Weissleder R et al. Circ Res. 2005;96:327-336.

Multimodal CLIO-Cy5.5-VCAM-1 Peptide (Iron-peptide) TARGETED SUPERPARAMAGNETIC NP

Amino-Cross-linked Iron Oxide =Amino-CLIO

In vivo Macrophage Imaging Using Iron Oxide Particles inAtherosclerotic Rabbits

GRASP (white spots)T2* GRE (dark spots)

24h POST CONTRAST

Lipoprotein carrier Natural Affinity to plaques Small size (7-12 nm) Does not trigger immune reactions Easily reconstituted Efficient drug carrier

Frias JC et al. J. Am. Chem. Soc. 2004 126(50): p. 163-167

HDL Properties

ApoA-I

DMPE-NBD(optical)

UnesterifiedCholesterol

CholesterolEster

Gd-DTPA-DMPE(MRI)

Triglyceride

Phospholipid

r1p = 10.4 mM-1s-1 (1.5 T, 25 °C)

Imaging Science LaboratoriesFrias JC et al. J. Am. Chem. Soc. 2004 126(50): p. 163-167

119 98

52

37

30

22

apoA-I

HDL

rHDL + Gd-DTPA-DMPE

kDaGdGd-DTPA-DMPE-DTPA-DMPE

rr1p1p = 10.4 mM = 10.4 mM-1 -1 ss-1-1 (1.5 T, 25 (1.5 T, 25 °°C)C)4-12% SDS-PAGE

DPPE-NBD

HNO O

P

O

OHO

H O

O

O

NO2

NO

N

14

14

reconstitutiondelipidation

Control

NNH

O

O

OP

O

OHO

H O

O

O

N

O

N

O OO

O O

OO

Gd

J. C. Frías et al., J. Am. Chem. Soc., 2004, 126, 16316

12

12

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80

Fraction number

Abs

280

nm

rHDL-spherHDL-discapoE-KO plasma (x10)incubated HDL

VLDL

LDL IDL HDL

Cholesterol estersTriglyceridesGadolinium complex

Phospholipids

ApoA-I

Reconstituted hollowspherical HDL

Reconstituteddiscoidal HDL

Native incubated HDL

Pre-contrast 48 hours post-contrast1 hr post-contrast 24 hr post-contrast

ApoE-KO mice; 4.36 mmol/kg @ 9.4-T MRM rHDL-Gd-DTPA-DMPE

Frias JC et al. J. Am. Chem. Soc. 2004 126(50): p. 163-167

DAPI srHDL-NBD CD68:RPEM

rHDL for Plaque Detection in ApoE KO Mice

Silvia Aguiar, MD Gilbert Aguinaldo, MD Vardan Amirbekian Lucy Feliciano JC Frias, PhD Fabien Hyafil, MD Vitalii Itskovich, PhD Alex Leber, MD Enric Lopez, MD, PhD Michael Lipinski Frank Macaluso, RT

NIH/NHLBI R01HL71021; R01HL78667; R43HL71470 Intellectual Property Managed by Mount Sinai

Venkatesh Mani, PhD Lena Mara Gabor Mizsei, MS Dan Samber, MS Karen Saebo, PhD Marc Sirol, MD Cheuk Tang, PhD Hiraoki Taniguchi, MD Esad Vucic, MD Karen Weinshelbaum

Imaging Science Laboratories (ISL)

Mount Sinai School of Medicine

Valentin Fuster, MD, PhD Donald Smith, MD Jonathan Halperin, MD Pedro Moreno, MD K-R Purushothaman, MD Michael Farkouh, MD Mary Ann McLaughlin, MD Jeffrey Olin, MD Alison Schecter, MD

Radiology Burton Drayer, MD Zvi Lefkovitz, MD Bradley Delman, MD Emil Cohen, MD

CVI

Jesse Weinberger, MD Stanley Tuhrim, MD

Neurology

Sanjay Rajagopalan, MD Javier Sanz, MD Santo Dellegrottaglie, MD

Clinical CMR/CT

Mount Sinai School of Medicine

Collaborators Edward A. Fisher, MD, PhD John Postley, MD Carlton Boxhill, MD Lisa Hudgings, MD Christine Williams, MD Tom Starc, MD  Sam Gidding, MD Kevin Williams, MD Yukihiko Momiyama, MD Jean-Francois Toussaint, MD, PhD

Pathology John T. Fallon, MD, PhD

Pediatrics Jeff Saland, MD

The following relationships exist related to this presentation:

SOME CONTRAST AGENTS DISCUSSED ARE NOT FDA APPROVED

Presenter Disclosure Information

NIH/NHLBI R01HL71021; R01HL78667; R43HL71470 Siemens Medical Solutions Pfizer/GE HealthCare Guerbet Schering Society of Atherosclerosis Imaging (www.SAI.ORG) President

Society of Cardiovascular Magnetic Resonance Board Member

Intellectual Property Managed by Mount Sinai