应用优化的全自动免疫组化染色方案检测错配修复蛋白MLH1、PMS2在结直肠癌组织中的表达

目的:通过优化的全自动免疫组化检测方案提高MLH1和PMS2蛋白免疫组化检测的稳定性。方法:收集2018年至2019年大坪医院结直肠癌手术标本20例，经石蜡包埋、切片、染色，显微镜下观察错配修复蛋白表达的差异。采用Ventana公司生产的BenchMark Ultra，二抗检测系统分别采用UltraView Universal DAB Detection kit(简称UV)、Optiview DAB IHC Detection kit(简称OV)和扩增试剂盒。结果:BenchMark Ultra染色机采用UV二抗检测系统错配修复蛋白的表达强度偏弱，背景不清晰，PMS2的表达可能会出现假阴性。优化染色方案后，改用OV二抗检测系统，MLH1和PMS2（PMS2需用扩增试剂盒）染色各项指标优于UV二抗检测系统，染色效果和手工相比，染色强度和阳性率比手工略好。结论:MLH1、PMS2等抗体指标在应用全自动免疫组化染色机染色前均需进行最适条件的摸索与优化，从而获得该抗体指标最佳的染色方案。

Detection of mismatch repair protein MLH1 and PMS2 expression in colorectal cancer tissues by optimized automatic immunohistochemical staining scheme

Objective:To improve the stability of immunohistochemical detection of MLH1 and PMS2 proteins by optimized automatic immunohistochemical staining scheme.Methods:Twenty cases of colorectal cancer surgical specimens from Daping Hospital from 2018 to 2019 were collected.The expression of MLH1 and PMS2 was observed by microscope after paraffin embedding,sectioning and staining.UltraView Universal DAB Detection kit (UV) and Optiview DAB IHC Detection kit (OV) and amplification kit were used for the secondary antibody detection system.Results:In the detection of MLH1 and PMS2,signal obtained by UV secondary antibody detection system in BenchMark Ultra dyeing machine was weak,accompanied with blurry background,making the expression of PMS2 appear false negative.After the optimization of the dyeing scheme,OV secondary antibody detection system was used.The detection of MLH1 and PMS2 (PMS2 required amplification kit) staining were better than that of UV secondary antibody detection system.Compared with manual staining,the dyeing intensity and positive rate were slightly better than manual staining.Conclusion:The optimum conditions should be explored and optimized before the application of automatic immunohistochemical staining machine,especially in the detection of MLH1 and PMS2,thus to obtain the best staining scheme for the antibodies.