Melissa A. Moss, Ph.D. – Protein Self-Assembly - SC EPSCoR/IDeA

Biological Engineering at USC 

Junior Faculty Presentations 

Esmaiel Jabbari Jay Blanchette 

Melissa Moss Xiaoming He 

Guiren Wang Arash Kheradvar 

October 23, 2007

Biomimetic Polymers & Tissue Engineering 

Esmaiel Jabbari, PhD 

Associate Professor, USC Department of Chemical Engineering 

Adjunct Professor of Orthopaedic Surgery, USC School of Medicine

Growth Factor Delivery and Scaffold 

Fabrication 

Cell encapsulation 

for cartilage 

regeneration 

Injectable 

nanocomposite 

for bone repair 

Nanosphere for 

tumor delivery 

Microsphere for 

DNA delivery 

Nanofibers 

fabricated by 

template 

biopolymerization 

Preformed scaffold 

For guided bone 

regeneration

Multi-Functional Biomimetic Scaffolds 

Peptide Reinforced Nanocomposite 

Bone microstructure 

Scaffolds functionalized 

with cell-adhesive peptides 

Scaffolds that induce 

cell migration

Peptidomimetic Nanospheres 

Lack of selectivity 

has limited the 

use of anticancer 

drugs to more 

invasive and 

localized 

methods 

Peptidomimetic nanospheres for 

Targeted tumor delivery 

Targeted to intestinal tumor 

Targeted delivery to tumor cells

Nanofibers and Cell Differentiation 

Random fibers 

Cells align along the fiber direction 

Aligned fibers 

Osteogenesis 

Vasculogenesis 

Vasculogenic Osteogenesis

Publications 

1. Sarvestani AS, Jabbari E. Biomacromoelcules, 7: 1573-1580 (2006). 

2. He X, Jabbari E. Protein & Peptide Letters, 13: 715-718 (2006). 

3. Jabbari E, He X. J. Mater. Sci. Mater. Med., in Press (2006). 

4. Sarvestani AS, He X, Jabbari E. Biomacromolecules, 8-2: 406-415 (2007). 

5. Sarvestani AS, He X, Jabbari E. Biopolymers, 85-4: 370-378 (2007). 

5. He X, Jabbari E. Biomacromolecules, 8:780-792 (2007). 

6. Sarvestani AS, Jabbari E. Polymer Composites, in Press (2007). 

7. Sarvestani AS, Jabbari E. Macromol. Theory Simul., in Press (2007). 

8. Sarvestani AS, He X, Jabbari E. Materials Letters, in Press (2007). 

9. Xu W, He X, Sarvestani AS, Jabbari E. J. Biomat. Sci. Polym. Ed. in Press (2007). 

10. Sarvestani AS, He X, Jabbari E. Euro. Biophys. J. in Press (2007). 

11. Jabbari E, Tavakoli J, Sarvestani AS. Smart Mater. Struct. In Press (2007). 

12. Jabbari E, He X, Sarvestani AS, Xu W. J. Biomed. Mater. Res., in Press (2007). 

13. Sarvestani AS, Xu W, He X, Jabbari E, Polymer, in Press (2007). 

14. Henderson JA, He X, Jabbari E. Macromol Biosci. [Epub ahead of print] (2007).

Melissa A. Moss, Ph.D. – Protein Self-Assembly 

• PhD 

– Chemical Engineering 

– Thesis: Effect of TNF-α and shear stress stimuli on the 

adhesion of human breast cancer cells to endothelial 

monolayers 

– Supported by NSF Graduate Research Fellowship 

• Postdoctoral 

– Biochemistry/Neuroscience 

– Protein mis-folding in Alzheimer’s Disease 

– Supported by AHA Florida-Puerto Rico Affiliate 

Postdoctoral Fellowship 

College of Engineering and Computing 

University of South Carolina


Understand how 

monomeric protein 

self-assembles to 

form amyloid fibrils 

Alzheimer’s Brain 

Amyloid 

Plaques 

Nanotechnology 

applications 

Food and 

pharmaceutical 

industry 

Disease 

progression 

Courtesy of D. Dickson, 

Mayo Clinic, Jacksonville 

Pathology 

Nichols et al. (2002) 

Biochemistry, 41: 6115-27 

Aβ Fibrils 




Elongation 

Understand how Aβ self-assembles 

to form fibrils 

Aβ 

μM 

40 

20 

Protofibril 

Monomer 

30 

20 

10 

mAU 

(280nm) 

Isolate 

aggregation 

intermediates to 

study their growth 

Association 

0 

0 

4 8 12 16 

Volume, mL 

Determine the effect 

of various growth 

mechanisms on 

aggregate morphology 

Funding: NSF CAREER Award 




Elongation 

Utilize inhibitors to 

understand, control 

protein self-assembly 

Identify, characterize 

inhibitors that target 

specific growth 

mechanisms 

Association 

1000 

F 

500 

0 

Control 

O 

O N N 

N HN 

0 2 4 6 

Time, h 

Define inhibitor 

structure-function 

relationships 





Au 

electrode 

surface 

biotin 

tag 

avidin 

unlabeled 

soluble 

aggregate 

biotinylated 

Ab 1-40 

monomer unlabeled Aβ 1-40 

monomer 

Δm, pmol/cm 2 

Employ novel techniques to quantify 

Aβ self-assembly 

300 

200 

100 

A 

0 

0 2 4 6 8 

time, min 

60 

40 

20 

0 

-Δf, Hz 

Mimic cell-surface growth 

Correlate growth with 

physiological activity 

Δm, pmol/cm 2 

60 

40 

20 

0 

100 

XTT 

% 

Control 

0 2 4 6 8 10 

time, min 

0 

A 

Quartz Crystal 

Microbalance 

Monomer 

5 μM Fibril + Monomer 

5 10 20 30 

[Aβ Monomer], μM 


New Investigator Grant, Alzheimer’s Association 

Publication: Kotarek and Moss, “Implementation of a Quartz Crystal Microbalance to 

Detect Growth of Intermediates of the Amyloid-β Protein,” In Preparation, 

Analytical Biochemistry 




Alzheimer’s Brain 

Courtesy of D. Dickson, 

Mayo Clinic, Jacksonville 

Pathology 

Nichols et al. (2002) 

Biochemistry, 41: 6115-27 

Funding: 

Publication: 

Cerebral 

Amyloid 

Angiopathy 

Characterize physiological 

activity of Aβ aggregates 

Correlate activity 

with 

aggregate size 

Demonstrate 

specific effects of 

intermediates 

on endothelial cells 

Aβ Fibrils 

Beginning Grant-In-Aid, AHA Mid-Atlantic Affiliate 

Gonzalez-Velasquez and Moss, “Soluble Aggregates of the Amyloid-β 

Protein Activate Endothelial Monolayers for Adhesion and Subsequent 

Transmigration of Monocyte Cells,” In Press, Journal of Neurochemistry 




Lab Group: 

Postdoctoral Fellow 

Francisco Gonzalez 

Graduate Students 

Joseph Kotarek 

Adriana Reyes Barcelo 

Deborah Soto 

Chen Suo 

Undergraduate Students 

Charlotte Cooper 

Kathryn Johnson (Magellan) 

Fahmin Basher (Magellan) 

Tim Davis (Magellan) 

Sarah Holton (Magellan) 

Chris Butch (Magellan) 

Brandon Murphy (USC-PH) 

Corelis Zayas Ortiz (NSF-REU) 

Elizabeth Schongar (NSF-REU) 

Meagan Stewart (NSF-REU) 



Nano Laser-Induced Fluorescence 

Photobleaching Anemometer (nLIFPA) 

Guiren Wang 

Department of Mechanical Engineering 

& Biomedical Engineering Program, USC

Background 

Education 

• Postdoc, Microfluidics Lab, Stanford University 2002 

• PhD, Technical University Berlin 1999 

Research interest: multidisciplinary fields in 

• Micro/Nanofluidics, sensor, Lab-on-a-Chip 

• Biomechanics, drug discovery/delivery 

• Fluid mechanics, turbulence and mixing 

• Optical measurement, laser-induced fluorescence 

• Bioreactor and tissue engineering 

As Principle investigator (PI) for: 

• DARPA/(SBIR): 11/06-07/07 

Novel Nanofluidics-Based Sensor System 

• NIH/SBIR: 09/04–09/05 

Novel Micro Thrombectomy Catheter for Ischemic Stroke 

• OSD(DoD)/SBIR: 12/05–01/06 

Novel Electrothermal microfluidic Drug Infusion Pump 

Lab-On-A-Chip 

GPCR 

G q PLC 

PIPDAG 2 + IP 3 

[Ca 2+ ] i 

Cell 

Signal transduction 

Optical diagnostics 

Biodefense 

• Professional service: 

NIH panel review 

Bioreactor in tissue eng. 

Tissue cutting

Highly demanded for novel flow velocimetry 

• When flow Reynolds number (Re) becomes small and many 

biological processes occur at low Re 

• Nanofluidics and microfluidics 

• Chemical binding kinetics near surface, particularly for weak 

binding, e.g. hydrogen bond 

• Endothelial surface layer: mechanism of flow resistance reduction 

• Mechanotransduction 

• Platelet-Endothelial Cell Adhesion 

• Tribology, where lubrication failure leads to wear in prostheses 

• Shear stress measurement 

• Particle-liquid suspension flows near solid surfaces for polish 

silicon wafers in chip manufacturing

The state-of-the-art on velocimetry 

• Flush time of a neutral marker 

• Sample weighing 

• Conductivity cell 

• Current monitoring 

• Streaming potential 

• Nuclear magnetic resonance 

• Hot Wire Anemometer 

• Laser Doppler Velocimetry 

• Nano/Micro Particle Image Velocimetry (n/µPIV) 

Molecular tracer method 

• Photobleaching based velocimetry 

Easy to use, but 

low temporal and 

spatial resolution 

Difficult to use 

Successful used 

but limited 

resolution 

– Flush time: Low temporal and spatial resolution 

– Recovery time: High spatial resolution, low temporal 

– Laser-Induced Fluorescence Photobleaching Anemometer (LIFPA)

Key issues and emerging techniques 

Key issues 

• Molecular tracer 

• Molecular tracer signal transducer 

• Overcoming the Abbe’s diffraction limit (> 150 nm) 

Emerging techniques 

• Velocimetry: 

– LIFPA: molecuar tracer, high spatial and temporal resolution 

• Breaking diffraction limit 

– Standing wave or evanescent wave total internal reflection 

• Resolution: ~ 100 nm, but cannot measure transverse distribution 

– Stimulated emission depletion (STED) 

• Resolution: ~ 16 nm (X), 20nm (XY) and 50nm (Z) (Heintzmann and Ficz, 2006)

Laser-Induced-Fluorescence Photobleaching 

Anemometer (LIFPA) in microfluidic system 

Motivation: 

1. Electrokinetics flow 

measuring and calibration 

2. Flow velocity measurement 

in BioMEMS 

Simplified model 

for LIFPA 

I f = I f0 * e –t / τ 

t = df / u 

I f = I f0 * e – df/ (uτ) 

I f : Fluorescence intensity 

τ: Bleaching constant 

t: Dye residence time

Preliminary data 

Signal transduction 

Fluorescence intensity ( Arbitrary unit)I f 

35 

30 

25 

20 

15 

10 

Different u 

5 

0 

0 20 40 60 80 100 120 140 

Time (s) 

Time 

Calibration curve 

F lo w v e lo c ity (m m /s ) 

4 

3.5 

u 

3 

2.5 

2 

1.5 

1 

Calibrated curve 

Measured velocity 

0.5 

0 

0 10 20 30 40 

Fluorescence intensity (arbitrary unit) 

I f 

Set-up 

Wang, GR, et al(2007) Electrophoresis. In press. 

Wang, G. R. (2005) Lab on a Chip, 5, 450 – 456.

Stimulated emission depletion (STED) 

Hell 2003, Nature Biotech

We propose: nanoLIFPA, i.e. LIFPA + STED and TIR 

• Generating ultra fine laser illuminated measuring spot 

– Total Reflection 

– Stimulated emission depletion 

• Measuring velocity with LIFPA 

LIFPA + STED 

•STED can possibly focus to only 

30 nm diameter 

Detector 

LIFPA + Evanescent wave (TIR) 

•Evanescent wave can illuminate in 

thickness of 100 nm near the wall 

STED 

Excitation 

Nanochannel

Rapid mixing applications in biorengineering 

Many cases fast mixing at low Re and shear force 

in continuous operation is desirable 

Mixing 

application 

• Combustion 

• All fast chemical reaction process 

• Bioreactor (Tissue engineering, Fermentation, cell 

culture, extraction and etc) 

• Producing pure plasmid DNA 

• Protein folding 

• Cell activation 

• Slow enzymatic reaction for drug discovery 

• Immunoassay 

• Crystallization and nanoparticle 

• Cell and protein protection from rupture

Bioreactor for tissue engineering and vaccine: 

Using novel flow and mixing control 

Current problem 

Tissue engineering 

• limited understanding of 

physicochemical culture 

parameters 

• high manufacturing costs Too 

high turbulent eddies and shear 

force Cell damage 

Large size plasmid DNA for gene 

vaccines 

• Lysis process requires rapid 

mixing 

• But shear force can damage to cell 

and chromosomal DNA 

Research plan 

• Flow control based on the new 

receptivity 

• In vitro models to study the 

pathophysiology 

• Enhanced transport at low Re and low 

shear force 

• Precisely controlled biological and 

chemical condition 

• Precisely controlled mechanical force 

• Cell seeding on 3D scaffolds 

• Increase of mass transport 

• Drug screening

Calibration curve and measured 

electroosmotic flow (EFO) velocity 

LIFPA can measure EOF rapidly and accurately 

I f 

Fluorescence intensity (arbitrary unit) 

35 

30 

25 

20 

15 

10 

5 

0 

0 1000 2000 3000 

Voltage (V) 

Voltage 

u 

EOF velocity (mm/s) 

3 

2.5 

2 

1.5 

1 

0.5 

0 

0 500 1000 1500 2000 2500 3000 

Voltage (V) 

calibrated result 

measured result 

Voltage

Chip quality test 

• Pressure driven flow is normal 

• But the Electroosmotic flow (EOF) is abnormal 

Pressure driven flow 

Electroosmotic flow

Chip quality test 

•Electroosmotic flow (EOF) is normal 

•But the Pressure driven flow is abnormal 

Pressure driven flow 

Electroosmotic flow

Presentation to NSF/EPSCoR Outreach 

Visit - October 23rd, 2007 

Jay Blanchette 

Background 

B.S.E. – Biomedical Engineering, Duke University 

Predoctoral – National Cancer Institute, Bethesda, MD 

Ph. D. – Biomedical Engineering, Purdue University / The 

University of Texas – Austin (NSF IGERT) 

Postdoctoral – Dept of Chemical and Biological 

Engineering, University of Colorado - Boulder

Designing Delivery Systems for 

Therapeutic Agents 

• Doctoral Work: Synthetic delivery systems 

(pH-responsive hydrogels) for oral 

administration of chemotherapeutics 

• Current Research: Bio-synthetic hybrids to 

achieve sustained and responsive delivery 

of therapeutics (current research focuses 

on treatment of diabetes)

Site and 

Mechanism of 

Delivery 

Intestinal epithelium 

Drug carrier 

Mucosal Layer 

Intestinal Lumen

Cell Encapsulation 

Shield the transplanted cells from the body’s 

immune system while still allowing passage of 

nutrients and waste products to maintain cell 

function 

Semi-permeable 

membrane to 

shield the Islets of 

Langerhans – 

artificial pancreas

Stresses Related to Removal of 

Islets from the Pancreas 

Stresses are placed on the 

clusters of cells 

Foreign Environment – Cells 

know when they are in the 

wrong place and generally 

trigger their own death 

(Anoikis) 

Hypoxia – Without sufficient 

oxygen supply, the islets will 

not function properly

Signal Transduction Targets : ILK 

Target integrin-linked kinase (ILK) to try and keep cells 

functioning properly in foreign environment 

[Figure from N. Yoganathan et al Pharmacol Ther (2002)]

“Hotwiring” the Pro-survival 

Signaling Pathway 

- The islets are surrounded by 

a biologically inert capsule 

- Genetic modification of the 

islets can make them think that 

they are instead surrounded by 

appropriate matrix proteins 

which keeps them alive and 

releasing insulin

Insulin Release from 

Encapsulated, Whole Islets 

1.5 

Normalized 

Insulin 

Release 

1 

0.5 

Cre 

Bcl-2 

mILK 

0 

0 7 14 21 28 

Time (Day) 

Relative amount of insulin released compared to Day 1 of 4 week study

Role of Hypoxia in Loss of Islet Function 

-Develop a marker to identify islets in a 

hypoxic state 

-Creation of a recombinant adenovirus 

for use as a hypoxia reporter 

- Place red fluorescent protein under the 

control of the hypoxia response element 

(HRE) 

Hif-1 

HRE 

DsRed

Hypoxia Reporter System 

Normoxia 

24h at 1% O2

Bio-synthetic Hybrids 

• If you can keep tissue functional, then sustained 

and responsive delivery systems can be created 

• Research focused on development of artificial 

pancreas has applications in cell-material 

interactions and use of living tissue for delivery 

• The complexity of the cells opens up options that 

are not realistic with purely synthetic delivery 

systems (ability to respond to 1 or more stimuli 

and sustained release)

Xiaoming He, Ph.D. 

Education: PostDoc: Harvard Medical School, 2007 

Ph.D.: University of Minnesota, 2004 

M.S., B.S.: Xi’an JiaoTong University, 1998, 1995 

Positions: Assistant Professor: Biomedical and Mechanical Engineering, 2007- 

Research Associate: Massachusetts General Hospital (MGH), 2004-2007 

Research Associate: Shriner Hospital for Children, Boston, 2004-2007 

Development Engineer: American Medical Systems, Inc., MN, 2003-2004 

Assistant Professor/Lecturer: Beijing University of Technology, 1998-2000 

Publications: Journal 15 + 3 submitted; Conference 15; Patent 1 pending 

Activities: Co-Chair: Biotransport Session, ASME Summer Bioeng. Conf. 2005 

Reviewer: 7 Journals, 3 Conferences 

Societies: ASME, Society for Cryobiology, SPIE, Sigma XI 

Awards: Best Poster Award, European Association of Urology 2003 

Travel Award, Society for Cryobiology 2002

Heat and Mass Transfer in Biological Systems 

Minimally invasive surgery: Cancer and other diseases 

Cryosurgery 

Hyper-thermic surgery 

-196 o C -80 

-20 0 20 37 45 

100 o C 

Deep Cryo 

Cryo Hypo Normo-thermic 

Tardigrade 

(Water bear) 

Cryoprotectants: DMSO, glycerol 

Dehydrated 

Rehydrated 

Lyoprotectants: Trehalose, sucrose, glucose 

BioPreservation: 

Germplasm (sperm and eggs) 

Stem cells & primary cells 

Engineered and native tissues

Engineering and Sciences 

ThermoMechanical 

Biotransport, Biophysics, and Biomechanics 

Biological 

molecule, cell, tissue Injury, and function 

Inflammatory 

Necrosis 

Thermal Fixation 

Alive Peripheral 

Probe Site 

FEM thermal analysis 

Ice formation 

FTIR: Thermal protein 

denaturation in cells 

Histology: thermal 

injury in kidney tissue 

Control 

Thermally 

treated 

Intracellular delivery 

of bioprotectants 

FEM stress analysis 

in frozen tissue 

Live/dead assay: cell 

membrane integrity 

Functional analysis 

after biopreservation

Engineering and Scientific Challenges in Thermal Surgery: 

Molecular and Nanoscale Targeting 

EM Field 

Probe T(t) 

Diseased 

Tissue Diseased 

Tissue 

Normal 

Tissue 

∗ Sensitizing diseased tissue using 

chemical adjuvants (e.g. TNF-α) 

∗ Nanoencapsulation of chemical 

adjuvants for controlled delivery 

∗ Metallic nanoparticles for 

targeted heating

Engineering and Scientific Challenges in Biopreservation: 

A Look on the Phase Diagram 

T, o C 

T m,Sugar/CPA 

Liquid 

22 

0 

-5 

Liquidus 

Ice + 

Sub-cooled Liquid 

Extended Liquidus 

Solidus 

Sugar/CPA + 

Super-saturated Liquid 

Glass Transition 

T g,Sugar/CPA 

Dry or 

Desiccation 

-137 

-196 

Cryo 

Vitrified or Glassy State 

0% 

Sugar/CPA Concentration 

100% 

CPA: Cryoprotectant

Engineering and Scientific Challenges in Biopreservation: 

Ultra-Fast Vitrification and Desiccation at the Sub-Micron Scale 

T, o C 

T m,Sugar/CPA 

Liquid 

22 

0 

-5 

Ice Formation 

Freeze Concentration 

Toxic 

T g,Sugar/CPA 

IV 

-137 

Glass Transition 

I: Slow Freezing 

II: Vitrification 

-196 

III 

Vitrified or Glassy State 

II 

I 

III: Ultrafast Vitrification 

IV: Desiccation 

0% 

Sugar/CPA Concentration 

100% 

CPA: Cryoprotectant

Summary 

Future Research: Micro, Molecular, and Nanoscale 

Thermomechanical and Biological Responses in 

Biopreservation and Minimally Invasive Surgery 

Broader Impact: 

∗ Enhancement of the South Carolina Biological 

Engineering Research Infrastructure 

∗ Environmental Conservation of Endangered Species 

∗ Contribution to Food Industry 

∗ Contribution to the Nation’s Health Care

Targeting Support from NSF: CAREER … 

Thank you!

Arash Kheradvar, M.D., Ph.D. 

• Assistant Prof. of Mechanical Engineering 

• Clinical Adjunct Assistant Prof. of Medicine 

• M.D. from Tehran University of Medical 

Sciences 

• Ph.D. from California Institute of Technology 

• Member of Editorial Board, American Journal of 

Artificial Internal Organs 

• Invited grant proposal reviewer for National 

Medical Research Council, Ministry of Health, 

Singapore.

Research Interests 

• Cardiovascular Engineering: 

◦ Biofluid Mechanics 

◦ Heart Valve & Stent Engineering 

◦ Cardiac Macro & Micro Mechanics 

◦ Cardiovascular Imaging

Biofluid Mechanics: Vortex formation 

time in Left Ventricle 

Pressure Forces 

Thrust 

∑ F = ρ 

∫ 

Ω 

D 

Dt 

U 

dV 

+ 

∫ 

( P − P ) ndS 

+ = 0 

J V A 

F R 

∂Ω 

Vortex ring 

Recoil 

⎛ 

⎜ 

T* 

⎝ 

= ∫ 

E -wave 

( t) 

⎞ 

dt ⎟ 

D(t) 

⎠ 

u Jet

Assessment of Cardiac Viscoelastic 

Properties

Application of Fracture Mechanics 

in Ventricular Remodeling 

Normal Induction of a defect Defect propagation

Novel approaches toward developing: 

minimally-invasive invasive heart valves 

Kheradvar A, et al. Implantable small 

percutaneous valves and the method of 

delivery (US20060195180) 

Kheradvar A & Gharib M. Deployable forming 

heart valve system and its percutaneous method 

of delivery. patent pending 

Kheradvar A & Gharib M. Monolithically forming 

valve system and its percutaneous method of delivery. 

Patent pending

Helical to Circular Transformation

NSF-MRI: Acquisition of a high precision 

laser cutting system: for precise, clear 

cutting of special materials

Melissa A. Moss, Ph.D. – Protein Self-Assembly - SC EPSCoR/IDeA

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