student research day - Case Western Reserve University School of ...

Stephanie Michal
Establishing if accelerated atherosclerosis mediated by periodontal disease is
attributed to CD36
Stephanie Michal, Maria Febbario
Cell Biology Department
The Cleveland Clinic Lerner Institute
CD36 is an integral membrane glycoprotein found on the surface of many cell types and its functions include
recognition of apoptotic cells and modified lipids, uptake of fatty acids, regulation of angiogenesis and recognition
of ligands that trigger an innate immune response. This summer, I work in Dr. Maria Febbraio’s laboratory working
on establishing a link between the expression of CD36 and the development of atherosclerosis. The scavenger
receptor CD36 has been linked to a pro-thrombotic phenotype that is observed in metabolic states marked by
hyperlipidemia. Yet, when a CD36 knockout mouse is created there appears to be no difference between the
knockout and the wild type mice in the development of atherosclerosis. From these findings it has been
hypothesized that increasing the inflammatory stimulus that is associated with the generation of reactive oxygen
spices that causes oxidant stress is essential for the creation of CD36 specific pro-atherogenic ligands. It has
previously been proposed that there is a link between periodontal disease and atherosclerosis because periodontal
disease in some patients represents a state of chronic inflammation. The objective of the experiment this summer
was to determine if the atherosclerosis that is arbitrated to periodontal disease is CD36 dependent. In order to
perform the experiment I harvested macrophages from the peritoneum of both wild type and CD36 knockout mice
and plated the cells. Then four groups were formed, two wild type one with the bacteria in the media and one
without and two knockouts one with bacteria in the media and one without. After 24 hours the media was removed
and the macrophages were stained with oil red O (stains LDL) and fixed. The number of foam cells were then
counted using a light microscope. The expected results were that the most foam cells would be found on the plate
of wild type macrophages that contained media filled with bacteria however there was no statistical difference
between the plates. In conclusion, I would like to acknowledge the support I received to work on this project from
the T35 grant from the NIH.
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