Investigation of immune privilege in basal cell carcinoma

• Main Author: Gao, Wendi
• Language: English
• Published: University of British Columbia 2017
• Online Access: http://hdl.handle.net/2429/63553

Basal cell carcinoma (BCC) is the most common type of skin cancer which arises in the skin’s basal cells that line the deepest layer of the epidermis. Previous studies have identified some immune privilege (IP) related genes and products expressed in some malignancies. IP is also believed to exist in BCC tumors during BCC development. However, quantitative analyses and functional studies to clearly demonstrate IP in BCC tumors are required. My goal was to examine BCC tumor cells to identify novel functional mechanisms of IP. My hypothesis was that BCC tumors have functional IP capabilities. With in vitro experiments, I found that cultured BCC cells appeared to suppress histo-incompatible peripheral blood mononuclear cell (PBMC) T cells’ activation, as well as IFN-γ secretion. In contrast, non-tumor skin cells from the same subject elicited significant T cell activation. I screened for expression of candidate IP-related genes in BCC tumors relative to normal skin from healthy people by quantitative RT-PCR. I found significant upregulation of CD200, and a downregulation of its receptor CD200R. There were also several other genes related to IP expressed differently in BCC tumors compared to healthy control tissues. We also demonstrated the upregulation of CD200 and downregulation of CD200R at the protein level by flow cytometry. In summary, these experiments give further evidence in support of BCC IP and predict a potential role of CD200 in BCC IP. === Medicine, Faculty of === Experimental Medicine, Division of === Medicine, Department of === Graduate