IgH和IgL引物联合检测对提高石蜡组织淋巴瘤基因重排检出率的价值

Value of Combinational Detection by IgH and IgL Primers in Improving Detection Rate of Lymphoma Gene in Paraffin-embedded Tissue

背景与目的:通过聚合酶链反应(polymerasechainreaction,PCR)扩增免疫球蛋白重链(immunoglobulinheavychain,IgH)基因对其克隆性的检测,可以辅助诊断淋巴瘤。缺点是假阴性率较高,在石蜡包埋组织中尤为明显。本研究拟采用手工显微切割、免疫球蛋白重链和轻链(immunoglobulinlightchain,IgL)联合测定等方式,探讨该方法在石蜡包埋组织中非霍奇金淋巴瘤(non-Hodgkin\slymphoma,NHL)诊断中的价值。方法:选用1对IgH引物、1对T细胞受体γ(Tcellreceptorγ,TCRγ)、TCRγ引物、2对新设计的轻链引物,通过PCR、琼脂糖和聚丙烯酰胺凝胶电泳(PAGE)及银染技术,检测经形态学及免疫组织化学确诊的58例石蜡包埋组织标本,包括39例B细胞淋巴瘤、16例T细胞淋巴瘤和3例淋巴结反应性增生组织。以DG75和Jurkat淋巴瘤细胞系DNA作为对照。结果:IgH引物P1在39例B细胞淋巴瘤检出阳性率79.5%(31/39),假阳性率6.25%(1/16),IgL引物在B细胞淋巴瘤检出阳性率71.8%(28/39),假阳性率12.5%(2/16),经统计学分析二者检出率无显著性差异(P>0.05)。二者联合检测,B细胞淋巴瘤阳性检出率可以达到92.3%,假阳性率并无明显提高(12.5%)。以上重排引物在反应性增生淋巴结组织中均未检出。结论:IgH与IgL引物联合检测可明显提高石蜡包埋组织中B细胞淋巴瘤的检出率,并为B-NHL的诊断及鉴别诊断提供了有效的辅助手段。

BACKGROUND ＆ OBJECTIVE： Clonality detection through amplifying immunoglobulin heavy chain （IgH） by polymerase chain reaction （PCR） is a useful tool in diagnosis of lymphoma, but the false negative rate is high, especially in paraffin-embedded tissues. This study was to explore the value of tumor tissue microdissection and combinational detection of IgH and immunoglobulin light chain （IgK or Igλ） in diagnosis of non-Hodgkin＇s lymphoma （NHL）. METHODS. Two pairs of conventional primers for IgH and T-cell receptor γ （TCRγ）, 2 novel designed pairs of primers for Igk and Igλ, were used to detect 58 paraffin-embedded blocks, which had been diagnosed by pathology and histochemistry. Of the 58 cases of lymph node tissues, 39 were B-cell lymphoma, 16 were T-cell lymphoma, and 3 were reactive proliferative lymph node tissue. Lymphoma cell lines DG75 and Jurkat were used as control. RESULTS： The positive rates of IgH primers （P1） and IgL primers （Pk/Pλ） were 79.5% and 71.8% in the 39 cases of B-cell lymphoma （P〉0.05）, 6.3% and 12.5% in the 16 cases of T-cell lymphoma, respectively. The positive rate was greatly increased to 92.3% in combinationally detecting the primers for IgH and Pk/Pλ. There was no positive detection among the reactive proliferative lymph node tissues. CONCLUSION： B-cell lymphoma detection rate can be significantly improved by the combination of IgH and IgL gene rearrangement primers, which provides efficient assistant method for the diagnosis and differential diagnosis of lymphoma.