This study aimed to determine if high fructose corn syrup consumption could serve as a biomarker for atherosclerosis. Participants underwent blood sampling every hour for 24 hours to establish a baseline, then consumed high fructose corn syrup drinks with meals for two weeks. Follow-up 24-hour blood sampling analyzed monocyte activation and triglyceride levels. Results showed increased high fructose corn syrup led to elevated monocyte expression of adhesion molecules and triglycerides, suggesting it could be linked to atherosclerosis risk. Flow cytometry was used to distinguish monocyte populations and expression levels before and after the high fructose diet intervention.

1. Flow Cytometer analysis of
monocyte activation as a
biomarker for risk of
atherosclerosis.
Fatuma-Ayaan Rinderknecht
Gregory Foster
Dr. Scott Simon

2. Purpose of the Study
Cardio vascular disease associated with atherosclerosis
affects more than 1/3 of Americans. Atherosclerosis is a condition
where plaque starts to form on the walls of the arteries. This
plaque often limits blood flow and lead to more serious heart
conditions. Current biomarkers of atherosclerosis are only able to
identify 50% of diseased population. A biomarker is anything that
can be used as an indicator of a particular disease. The purpose
of this study is to find if high fructose corn syrup can be another
biomarker of atherosclerosis. These findings could lead to better
prevention, detection and treatment of atherosclerosis.

3. Study Design
24 hour study looking at TGRL
and monocyte activation to
establish baseline
Blood is drawn every
hour and analyzed
Individual is sent home with
case of high fructose corn
syrup drink to consume with
every meal for 2 weeks.
Individual returns after 2
weeks and 24 hour study is
repeated looking at TGRL
and monocytes.

4. Atherosclerosis and
Monocytes
Atherosclerosis is a condition in
which an artery wall thickens as a result
of the accumulation of fatty materials
such as cholesterol. The inflammatory
response in the walls of the arteries is
caused largely by the accumulation of
macrophage white blood cells and
promoted by low density lipopreteins
without removal of fats from the
macrophages by function high density
lipoproteins. Monocytes are a type of
white blood cell that is part of the immune
system. Monocytes replenish
macrophages and respond to
inflammation signals. Monocytes are
often tied to atherosclerosis because
when the endothelial walls of the arteries
become inflammed, monocytes are
recruited to that site, where the bind to
the wall and become part of the plaque.
Figure 1. Monocyte Adhesion to Arterial
Wall

5. Dr. Simon’s Lab
Dr. Simon’s lab focuses on white blood cells, like
monocytes and their role in cardiovascular disease. Monocytes
are the primary inflammatory cell type that infiltrates early
atherosclerotic plaques. Their recruitment into plaques drives
disease progression. The lab takes the blood samples from the
patients before and after their high fructose drink and analyzes
the role of the fructose in monocyte activity using flow
cytommetry. Monocytes take up circulating triglyceride rich
lipoproteins (TGRL), increase expression of adhesion receptors
(CD11c, CD11b, VLA-4, etc). These are receptors on the
monocyte cells that allow the monocyte arrest on endothelium.
This is one of the early events in plaque formation.

6. My Work in Flow Cytometry
While working in Dr. Simon’s lab, I focused on operating
and helping analyze some data obtained by the flow cytometer.
The flow cytometer is a machine that counts microscopic
particles by suspending them in a fluid and passing them by an
electronic detection apparatus and scatters light off of the
internal components of the cell. Using different
antibodies/flourophors for the monocytes, such as CD11b and
Cd11c, which are used as labels, I can use the flow cytometer
to distinguish monocyte populations in the blood samples of the
patients.

7. Working at the Flow Cytometer

8. How to Analyze Data
The data generated by flow ctymotery is usually in form
of a histogram or two-dimensional dot plot on a lograthmic
scale. In analyzing monocyte populations, I used a two
dimensional dot plot that graphed forward scatter (FSC) and
side scatter (SSC). FSC correlates with cell volume, and SSC
has to do with the inner complexity of the cell. I first “gate” the
monocytes on the graph, which seperates it from other
populations based on flourescent intensity. Because different
fluorescent dyes' emission spectra overlap, signals at the
detectors have to be compensated electronically as well as
computationally. Using software programs such as FlowJo and
CellQuest Pro, I was able to compensate the data and ready it
for further analysis.

9. Fluorescence-activated cell
sorting
Monocytes

10. Summary and Results
 This study was done to link the consuming of high fructose
corn syrup to atherosclerosis
 Monocytes adhesion to the walls of the arteries is associated
with plaque build-up in atherosclerosis
 Using flow cytometry, blood samples from people who had
high amounts of high fructose corn syrup in their diet were
tested for increased monocyte adhesion to endothelial walls
of the arteries
 It was found that increased high fructose corn syrup leads to
increased monocyte expression and triglyceride levels and
could be a biomarker of atherosclerosis

11. 0 2 4 6 8 10 12 14 16 18 20 22 24
-0.4
-0.2
0.0
0.2
0.4
0.6
Baseline
2 wks fructose
** **
**
time (hour)
MonocyteCD11cExpression
(foldchangefromfasting)
0 2 4 6 8 10 12 14 16 18 20 22 24
100
150
200
250
300
Baseline
2 wks fructose
time
TriglycerideConcentration
(mg/dL)
TGRL and CD11c increase following 2 week high
fructose corn syrup