| 摘要: | 近年來免疫治療已成為癌症治療重要選項之一，臨床治療上觀察到許多癌症中表皮生長因子受體（EGFR）會過量表現，因此被作為一癌症治療標靶。在本研究中將以anti-EGFR Fab/anti-CD3scFv的雙特異性T細胞接合體 (BiTEE) 作為研究標的，該抗體可同時接合EGFR與分化簇3受體 (CD3R)，具有對EGFR過度表現的細胞株達到專一性毒殺的作用，為了評估BiTEE的效果，我們首先使用流式細胞儀對A549、H1975、SKBR3、CRL2336以及HT29進行EGFR相對表現量以及實際結合量的分析，結果顯示A549、H1975、SKBR3、CRL2336的表現量無顯著差異，而HT29則明顯低於其他細胞株表現量約只有1/6左右。另外BiTEE的結合量分析也與表現量的結果相近。而在T cell毒殺試驗中發現EGFR的表現量與BiTEE協同T細胞的毒殺效果有正相關性，計算後也得出EC90越低的細胞株其EGFR表現越高。此外透過對EGFR外顯子（exon）基因定序得知除H1975帶有兩種突變外，其餘細胞株皆正常，顯示基因突變會影響細胞的毒殺效果。藥物動力學實驗中透過T細胞補充小鼠模型可以得知相較於靜脈注射，皮下注射有著較為平緩的濃度曲線，兩者的AUC分別為61961.38 ng*hr/ml±18783.34以及10503.38 ng*hr/ml±4338.38，Cmax為21548.04 ng/ml±9612.9和1918.63 ng/ml±958.15，且在含有T細胞的狀態下BiTEE的濃度曲線也並沒有明顯改變。而在小鼠建立之腫瘤模型的生物分佈實驗結果顯示，含有T細胞的組別相較於無T細胞的組別，在EGFR表現量低的腫瘤中BiTEE會增加約1倍，而較EGFR高表現的組別則會增加約4倍，表示EGFR表現量會影響BiTEE在腫瘤內的含量。經由以上的實驗結果可以推測EGFR表現量與BiTEE功效有正相關，並且證實EGFR的表現量在臨床的治療中具有相當的潛力。
In recent years, immunotherapy has become one of the important options for cancer therapy. In clinical treatment, it has been observed that the epidermal growth factor receptor (EGFR) was overexpressed in many cancers, so it was regarded as a cancer treatment target. In this study, an anti-EGFR Fab/anti-CD3scFv bispecific T cell conjugator (BiTEE) was evaluated. This antibody can simultaneously bind EGFR and cluster of differentiation 3 receptor (CD3R), and has an overactive effect on EGFR. The expressed cell line achieves the specific toxicity effect. In order to evaluate the effect of BiTEE, we first used flow cytometry to analyze the relative expression level and actual binding amount of EGFR on A549, H1975, SKBR3, CRL2336 and HT29. The results showed that four of them The expressive amount of the strains was equivalent, while the expressive amount of HT29 was about 6 times less. In addition, the analysis of the binding capacity of BiTEE was also similar to the results of the expression capacity. In the T cell toxicity test, it was found that there was no obvious positive correlation between the expression level of EGFR and the toxic effect of BiTEE synergized with T cells. In addition, it was learned through sequencing of EGFR exon genes that except for H1975 with two harmful mutations, the other cell lines All are normal, indicating that gene mutations may affect the cell's toxicity effect. In pharmacokinetic experiments, compared with intravenous injection, subcutaneous injection has a relatively flat concentration curve. The AUC was 61961.38 ng*hr/ml±18783.34 and 1503.38 ng*hr/ml ±4338.38, respectively, and the Cmax is 21548.04 ng/ml. ±9612.9 and 1918.63 ng/ml ±958.15, and the concentration of BiTEE did not change significantly in the state of containing T cells. The results of the biodistribution experiment showed that compared with the group without T cells, BiTEE in tumors with low expression of EGFR increased by about 1 times, and the group with higher expression of EGFR indicated an increase of about 4 Times, EGFR expression will affect BiTEE in tumors. Through the above experimental results, it can be inferred that clinical EGFR expression is positively correlated with BITEE, and has considerable therapeutic potential. |
