Allison Floyd

floyd
Investigating the efficacy of a synthetic peptide on inhibition of cortisol-induced apoptosis

ACTH-independent Cushing’s Syndrome is a disease of the adrenal cortex that results in excess production of the steroid hormone, cortisol. Excess cortisol causes a myriad of health problems, and efforts are underway to develop new treatments for this disease. I hypothesized that a peptide derived from human alpha-fetoprotein (hAFP) would be a cortisol inhibitor based on its ability to block the activity of another member of the steroid hormone family, estrogen. To test this, we observed DNA laddering as a measure of dexamethasone (synthetic cortisol)-induced apoptosis in a murine lymphocyte cell line (HT-2). The absence of DNA laddering indicated successful inhibition of dexamethasone in this system. However, my results show definitively that this peptide does not inhibit apoptosis induced by dexamethasone in the HT-2 cell line. In contrast, a known cortisol inhibitor, RU-486 (also known as mifepristone) inhibits apoptosis. Future studies will include investigating other cell lines to determine if the peptide is more efficacious against cortisol in other cells.

David VanHoute

vanhoute
The Development of an Anti-hLH-Receptor Antibody in Chickens for Identifying hLH Receptor Expression

The goal of this study is to develop an antibody that will allow for detection of Luteinizing hormone (LH) receptors in situ. Human diseases like polycystic ovarian disease and Cushing’s Syndrome are thought to be in part caused by incorrect expression of hLH receptors within these tissues. By developing an antibody targeting the extracellular domain of hLH receptors we will have the ability to detect hLH receptors when they are wrongly expressed.

To make an antibody, an antigen needs to be prepared. For generating anti-LH receptor antibodies, the extracellular domain of hLH receptor (hLHR-ECD) was selected as the antigen. The hLHR-ECD was expressed as a glutathione s-transferase (GST) fusion protein in the E. coli strain BL21. After constructing the expression plasmid, the conditions for expressing and releasing the fusion protein from the bacteria were established. The GST- receptor fusion protein was purified to homogeneity on Glutathione-sephadex beads. Large scale expression is currently underway to produce and purify milligrams of protein to be purified as used as an antigen to generate the anti-LH receptor antibodies.

Honorary Members:

Jennifer Eliseo- Advisor: Prof. Michael Hagerman, Chemistry