In-vivo optical imaging in experimental

arthritis models

Eline Vermeij

Department of Rheumatology

PRIME lecture

29-2-2012

Biophotonic imaging using the IVIS

• Fluorescent & bioluminescent reporters

• Detection in the range of 400-900 nm

• Multiple animals (3 mice / 2 rats) at once

• Minimally invasive

• Quick: 1-10 minutes per measurement

• Quantitative yet limited resolution

Rheumatoid Arthritis features

Rheumatoid Arthritis features

Inducible promoters

Disease-inducible promoter reporters

• In about 15-30% of the RA patients, the disease course is characterized

by an intermittent pattern of exacerbation and remission

• During disease course different genes are upregulated

• Promoter of a gene consists of a unique combination of transcription factor

binding sites

• Molecular imaging of transcriptional regulation of these genes during

disease can be done by using expression vectors

Disease-inducible promoter reporters

• Regulation of the expression of the genes in-vivo is largely unknown and

very complex

• With these promoter reporters we can mimic gene expression

• By using quantitative imaging we can visualize and calculate the

upregulation of genes

Geurts et al., 2009.

Disease-inducible promoter reporters

• Selected 10 different disease-inducible

promoter reporters in-vivo testing

• Synovial lining targeted via viral transduction

intra-articular injection

• Streptococcal Cell Wall arthritis (SCW)

In-vivo luciferase measurements

SAA3

In-vivo luciferase measurements Histological scoring

SAA3

In-vivo luciferase measurements Histological scoring

S100A8

SAA3

In-vivo luciferase measurements Histological scoring

S100A8

SAA3

Disease-inducible promoters are a valuable imaging

tool to monitor arthritis activity

• Imaging of the activation of cells in the synovial lining / gene

expression

• Follow up during disease progression

• Treatment respons

Rheumatoid Arthritis features

Activatable

and targeting

NIR-probes

Fluorescence imaging of activatable and targeting

probes

• ProSense:

Activated by cathepsin B, S, L, K inflammation

• MMPSense (Metalloproteinases):

Activated by MMP 2, 9, 13 bone and cartilage destruction

• OsteoSense:

Targets hydroxyapatite (bone mineral) active bone remodeling

Fluorescence imaging of enzyme activity and treatment response

in a mouse model of RA

• Collagen-induced arthritis chronic arthritis model

• IL-1 important pro-inflammatory cytokine

• Pre-treatment with anti-IL-1 should diminish disease and enzyme activity and

therefore fluorescent signal intensity

Fluorescence imaging of enzyme activity and treatment response

in a mouse model of RA

• Collagen-induced arthritis chronic arthritis model

• IL-1 important pro-inflammatory cytokine

• Pre-treatment with anti-IL-1 should diminish disease and enzyme activity and

therefore fluorescent signal intensity

Fluorescence imaging is a valuable tool to monitor the protective effect

of anti-IL-1 treatment

MMP activity in mouse model of OA

• Osteoarthritis (OA) is characterized by cartilage damage and bone spurs

• Less inflammation compared to rheumatoid arthritis

• MMP activity (cartilage and bone damage) expected, but no cathepsin

activity (inflammation)

MMP activity in mouse model of OA

• DMM model

• Destabilization of the medial meniscus

• Cartilage damage

• MMP activity in OA process?

• MMPSense and ProSense imaging at

week 8

MMP activity in mouse model of OA

• DMM model

• Destabilization of the medial meniscus

• Cartilage damage

• MMP activity in OA process?

• MMPSense and ProSense imaging at

week 8

DMM week 8

MMPSense

DMM/Control = 1.23

MMPSense ProSense

MMP activity in mouse model of OA

• DMM model

• Destabilization of the medial meniscus

• Cartilage damage

• MMP activity in OA process?

• MMPSense and ProSense imaging at

week 8

DMM week 8

MMPSense

DMM/Control = 1.23

MMP activity but no cathepsin activity during OA process in DMM model

MMPSense ProSense

ProSense and MMPSense in SCID model

• SCID model is a humanized mouse model for rheumatoid arthritis

• Transplantation of synovium from RA patients to immunodeficient SCID mice

• This model can be used to screen the effect of different therapeutics on human

material

• Protocol:

• D 0 = transplantation of biopsies subcutaneously on the back (ø 6mm)

• D 0-7 = engraftment period

• D 7-14 = treatment period

• D14 = imaging and sacrifice: collection of blood and synovial grafts

hIL-6

ProSense and MMPSense in SCID model

• Imaging with ProSense (inflammation) and MMPSense (MMP activity) at 14

days after transplantation

• Correlation ProSense with pro-inflammatory cytokine IL-8 in serum (r=0.95)

ProSense

ProSense and MMPSense in SCID model

• Imaging with ProSense (inflammation) and MMPSense (MMP activity) at 14

days after transplantation

• Correlation ProSense with pro-inflammatory cytokine IL-8 in serum (r=0.95)

MMPSense ProSense

ProSense and MMPSense in SCID model

• Imaging with ProSense (inflammation) and MMPSense (MMP activity) at 14

days after transplantation

• Correlation ProSense with pro-inflammatory cytokine IL-8 in serum (r=0.95)

NIR-fluorescent probes are useful tools to measure enzyme activity in

real-time and quantitatively

MMPSense ProSense

Acknowledgements

Department of Rheumatology

Radboud University Nijmegen

Medical Centre

• Onno Arntz

• Miranda Bennink

• Marije Koenders

• Wim van den Berg

• Fons van de Loo