T細胞在後天免疫系統中扮演重要的角色，T細胞會表達獨特的T細胞受器(TCR)基因，該基因經過V(D)J重組以識別特定抗原，因此TCR序列的集合反映了免疫庫的狀態。TRIg是分析TCR序列的獨特工具，它可以對非完整重組的序列進行分析，然而在分析的嚴謹度和便利性可再改進。在這裡本研究通過增修原始碼來改進TRIg，接著應用改進的TRIg在三個主題中。首先本研究研究T細胞淋巴癌(TCL)患者的TCR免疫庫，以提高目前標準之BIOMED-2檢測方式對TCL診斷的靈敏度。與健康個體相比，本研究發現一名BIOMED-2測試為陰性的患者，其免疫庫中未重組(NR)序列的比例最高。在NR序列中，J2-2P序列在患者中也最豐富，這表示J2-2P基因具有改善TCL診斷之生物標誌物的潛力。其次本研究探討了等位基因排斥背後的機制，本研究發現具有兩個完整重組(CR) TCR序列的細胞數量，比只有一個CR序列的細胞數量略低。而在具有兩個CR的細胞中，這兩個基因通常表現量不同。此外還觀察到框移突變現象，這些表示等位基因排除通過多種方式進行調節。最後本研究分析了肝移植患者的TCR免疫庫並檢查其與臨床特徵的關聯，本研究發現出現急性排斥患者的TCR免疫庫多樣性較高，且多樣性與年齡具有負關聯。由於年齡已知是急性排斥的危險因子，本研究合理的解釋年齡這危險因子背後的機制。

T cells are essential in the adaptive immune system. Each T cell expresses a unique T cell receptor (TCR) gene, which undergoes V(D)J recombination for recognizing a specific antigen. The collection of TCR sequences thus reflects the immune repertoire. TRIg is a unique tool for analyzing TCR sequences especially when they are not completely recombined (CR). However, it was not sound enough for rigorous and convenient analyses. Here, we improved TRIg by modifying codes and applied the improved TRIg in three topics. First, we studied TCR repertoires in patients with T cell lymphoma (TCL) for improving sensitivity of the diagnosis. Compared to healthy individuals, we found that the TCR gene J2-2P had a potential for enhancing the diagnosis of TCL. Second, we studied the mechanisms behind allelic exclusion of TCR gene. While the first TCR allele was always CR, we found that the second TCR allele of T cells were either non-recombined (NR) or CR in most T cells. In T cells with two CR alleles, the two alleles were usually expressed differently. Besides, one CR sequences was usually frame-shifted. Therefore, we found that allelic exclusion was regulated in at least three ways. Finally, we analyzed the TCR repertoire of liver transplantation recipients and examined the association with acute rejection. We found that recipients with a more diverse TCR repertoire tended to develop acute rejection and be younger. As young age was known to be a risk factor for acute rejection, we discovered a plausible mechanism behind the risk factor.

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