Biochemical characterization of an Oriental restricted non-HLA and non-minor histocompatibility antigen named CY

• Main Authors: none none, 鄭兆焜
• Other Authors: Kuo Liang Yang
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/05813692707589544485

碩士 === 慈濟大學 === 醫學生物技術研究所 === 96 === The Immune system of our body relies on the Major HistocompatibilityComplex (MHC) to present self or non-self antigens to T cells by which furtherimmune responses are elicited. In human, the MHC is called human leukocyteantigen (HLA) system. Apart from MHC, there is a minor histocompatibilitycomplex and its antigens are called minor histocompatibility (mH) antigens which also contribute to some immune functions.In this study, we focused on a protein named CY antigen. CY antigen was firstreported in 2003 (in European Journal of Immunogenetics) that it was observed in Chinese (from China, Hong Kong and Taiwan), Japanese, Thai, and Vietnamese.The antibody specific for CY antigen was found in the serum of a Caucasianwoman with a history of blood transfusion.mH gene study using SSP-PCR (sequence-specific primer-PCR) typing protocol,it indicated that CY antigen is not the mH antigens. Therefore, the initialassumption that CY antigen is not a mH antigen was proven correct as far as this investigation can determine to date.We extracted membrane proteins of white blood cells with CY antigen andwithout CY antigen. In Western Blot experiments, we proved the existence of CYantigen which has a molecular weight of around 28-29 KD. ImmortalizedEpstein-Barr virus (EBV) transformed cell lines were established to provideconstant supply of cell membrane materials from CY carrying and CY lackingindividuals for the extraction of CY protein for investigation purposes. Using the membrane protein for Western Blot assay, consistently, a protein with 28-29 KD was observed, proving the usefulness of the transformed B cell lines in CY investigation.Finally, we further analyzed CY antigen by two-dimensional electrophoresis analysis and mass spectrometry. Results obtained from mass spectrometry suggestthat CY antigen might be related to voltage-dependent anion-selective channelprotein 1 (VDAC-1) or voltage-dependent anion-selective channel protein 3(VDAC-3). Further study is necessary to discover the nature of CY antigen.