Abstract

Both major histocompatibility complex class I (MHC-I) molecules and Transporter associated with Antigen Processing (TAP) proteins are essential to elicit a proper immunological response against a malignant cell. In many cancer cells, these two important components are abnormal, deficient, or completely absent. Hence, the cancer cells are able to escape T-cell recognition and destruction. Previous research has shown that the introduction of TAP protein into TAP-deficient cancer cells helps the anti-tumor response in vitro and in vivo. In this project, an anti-tumor recognition response was examined for cancer cells that were transfected with TAP and MHC-I genes. My hypothesis was that the anti-tumor response would be greatly augmented with the addition of both MHC-I and TAP. To test this hypothesis, I performed three types of assays using nine mouse cancer cell lines, some of which were transfected with TAP protein and/or MHC-I genes. These lines included samples of mouse lung cancer cells transfected with MHC-I alone, TAP.1 alone, TAP.1 and TAP.2, TAP.1 and MHC-I, and the combination of MHC-I, TAP.1, and TAP.2. Appropriate controls were also used. A Western blot was used to identify the cell lines which express TAP protein. A Fluorescence-Activated Cell Sorting (FACS) analysis was performed to identify the cell lines which expressed MHC-I molecules. A 51Cr-release assay was used to measure immune recognition of each cell line. With the completion of these three assays, the results were analyzed to see if the immune recognition correlated to the TAP and MHC-I expression. Cancer cells transfected with the combination of MHC-I, TAP.1, and TAP.2 elicited the highest immunes response, as expected.