Hyeun-Ki Cho

 Hyeun-Ki Cho
Mentor: Dr. Paul Oh
College of Medicine
 
"I got involved with research because I wanted to learn something new and hone my problem-solving skills. While I believe that information one gains from classes is important, it is different to actually apply them in laboratory setting. Also, research challenges me in new ways to diligently work through frustrating and difficult experimental problems."

Major

Statistics

Minor

Mathematics

Research Interests

  • Medicine
  • Mathematical Modeling
  • Statistical Modeling

Academic Awards

  • UF University Scholars Program
  • HHMI Intramural
  • Dean's List
  • President's Award

Organizations

  • Dramagators
  • Alzheimers Outreach
  • Phi Kappa Phi

Volunteer

  • Shands Hospital
  • Feed-a-Need
  • Alzheimers Outreach

Hobbies and Interests

  • Watching Football
  • Working Out
  • Solving Math or Physics Problems

Research Description

Histological Analysis of AVM Vessel Formation
Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal dominant vascular disease that affects about 1 out of 5000 people worldwide. It is characterized by epistaxis (spontaneous and recurrent nosebleeds), mucocutaneous telangiectases as well as arteriovenous malformations (AVMs) in internal organs such as brain, lung, liver and gastrointestinal tract. AVM is a direct connection between artery and vein without intervening capillaries. Mutations in ALK1 (activin receptor-like kinase 1), ENG (endoglin), or SMAD4 have shown to be accountable for this malady. We have shown that deficiency of Alk1 gene is necessary but not sufficient in forming skin AVMs. Another factor, such as skin wound, is essential for the abnormal connections between arteries and veins. When a wound is placed on the skin of Alk1-deficient mice, new vessels resembling AVMs are formed. Alk1 deletion and skin wound are identified as the chief contributing factors to the formation of AVM. Recent data have shown that Alk1 regulates the recruitment of macrophages during wound healing and that macrophages are essential for the formation of wound-induced AVMs in tamoxifen-induced Alk1 knock-out (Alk1-iKO) model. To further investigate the roles of macrophages, we want to perform a longitudinal study over seven days to observe their recruitment during AVM formation. Macrophages will be detected by using F4-80 macrophage specific marker. In addition, other leukocytes and lymphocytes may be present. We suspect that T-cells, B-cells, and other white-blood cells may be recruited around AVM vessels since there is clinical evidence that shows mononuclear cells are accumulated around dilated vessels of skin AVMs. Identifying the cells that are recruited around AVM vessels will provide a strong foundation for further studies on AVM formation. There is also a necessity to observe the relationship between the blood and lymphatic vessels in Alk1-iKO models. Some data show that Alk1 deletion can affect lymphatic vessels in addition to blood vessels. Hence, in this project, I will study the progression of the AVM vessel growth through histological analysis of the back skins of Alk1-iKO. More specifically, the growth of arterial, venous, and lymphatic smooth muscle and endothelial tissues will be observed. By immunostaining the back skin tissue sections with venous, arterial, and lymphatic vessels specific markers, the changes in vasculature will be studied. A longitudinal study will be done over the length of seven days. This study will provide basic knowledge for further studies that may lead to a better understanding of the relationship between the two types of vessels. There are three goals to this experiment. One of them is to observe the progression of macrophage recruitment. The second goal is to discern the recruited cells around the dilating AVM vessels. From previous experiments, we established that macrophages are essential in the formation of AVM. The presence of other circulating cells is very probable. The final aim is to check the growth of AVM arterial, venous, and lymphatic vessels. These experiments are significant because they may provide information that will lead to further studies on AVM formation.