Active lambda and kappa antibody gene rearrangement in Abelson murine leukemia virus-transformed pre-B cell lines

The two Abelson murine leukemia virus (A-MuLV)-transformed cell lines, BM18-4 and ABC-1, undergo immunoglobulin L-chain gene recombination during passage in tissue culture. BM18-4 cells are capable of kappa gene recombination, whereas ABC-1 cells are capable of both kappa and lambda gene recombination. The expression of H chains is apparently not necessary for continuing L chain gene recombination in either of these cells, although H-chain expression may have been involved in the initiation of L-chain gene recombination. All ABC-1 cells that have lambda gene rearrangements also display recombined kappa alleles, supporting the hypothesis that kappa and lambda gene recombination are initiated in an ordered, developmentally regulated manner in maturing B cells. However, analyses of the ABC-1 line indicate that pre-B cells that have initiated lambda gene recombination do not terminate kappa gene rearrangement. The lambda gene recombinations that occur in the ABC-1 cell line indicate that the germline order of lambda gene segments is: 5' ... V lambda 2 ... J lambda 2C lambda 2-J lambda 4C lambda 4 ... V lambda 1 ... J lambda 3C lambda 3-J lambda 1C lambda 1 ... 3'. In addition, the frequencies of lambda 1, lambda 2, and lambda 3 gene recombinations among ABC-1 cells are quite different than the frequencies of B cells producing lambda 1, lambda 2, and lambda 3 L-chains in the mouse. RS DNA recombinations also occur in the BM18-4 and ABC-1 cell lines, supporting the notion that Ig gene recombinases are involved in RS rearrangement. Recombined RS segments are infrequent among BM 18-4 cells but common among ABC-1 cells, suggesting that RS recombinational events often occur in maturing pre-B cells just before initiation of lambda gene rearrangements. This developmental timing is consistent with the hypothesis that RS recombination may be involved in the initiation of lambda gene assembly.     

非霍奇金淋巴瘤与基因重排

研究非霍奇金淋巴瘤与基因重排的关系,用PCR技术检测免疫球蛋白重链基因(IgH)和T细胞受体γ基因(TCRγ)的克隆性重排。结果:①211例非霍奇金淋巴瘤患者中,IgH阳性108例,TCRγ阳性45例,双阳性12例,阴性46例;②系统观察10例患者,发现临床完全缓解时仍有5/10患者呈克隆性基因重排。结论提示,基因克隆性重排的PCR分析在非霍奇金淋巴瘤的早期诊断及评估治疗有效性方面是有用的。     

Origin of human T-lymphotrophic virus I-positive T cell lines in adult T cell leukemia. Analysis of T cell receptor gene rearrangement

Using the clone-specific rearrangement of the T cell receptor gene as the genetic marker of the clonotype, we analyzed the clonal origin of the interleukin 2 (IL-2)-dependent human T-lymphotrophic virus I (HTLV-I)-positive T cell lines established from various adult T cell leukemia (ATL) patients. From a patient with chronic ATL, whose leukemic cells proliferated in vitro in response to IL-2, we repeatedly established leukemic T cell clones having the same rearrangement profile of the T beta chain gene as the leukemic cells. By contrast, established cell lines from acute ATL patients had different beta chain gene rearrangements from those of the leukemic cells. These HTLV-I+ T cell lines might not be the direct progeny of the leukemic cells, but that of T cells infected either in vivo or in vitro. These IL-2-reactive nonleukemic T cells might have been selected in vitro, because their leukemic cells failed to respond to IL-2, despite the expression of IL-2 receptor. The analysis of the T cell receptor gene rearrangement may give a new approach for the elucidation of the mechanism of leukemogenesis and the origin of the HTLV-I+ T cell lines in ATL.     

Using standards and controls in molecular assays for infectious diseases.

Ten years ago, laboratory directors introducing molecular infectious disease diagnostics in the routine clinical setting had few resources to assist in their implementation and quality assurance programs. In the past 10 years, several organizations have recognized this need and have established standard reference materials, controls, external quality assessment programs, and written guidelines. It is a challenge for the clinical laboratory scientist to evaluate and incorporate these new programs and services in the context of traditional good laboratory practice and current laboratory regulations. This article presents many of the options available for control materials, proficiency programs, standard reference materials, and written guidelines. It shows where harmonization of new practice with long-standing convention and regulation is progressing and where questions remain.     

Preferential rearrangement of V kappa 4 gene segments in pre-B cell lines

Examination of the in vitro V kappa gene rearrangements of murine adult bone marrow-derived pre-B cell lines reveals that 21 of 25 (84%) cell lines have rearranged a member of the V kappa 4 family. In contrast, analysis of two V kappa cDNA libraries prepared from LPS-stimulated adult spleen cells indicates that only 17% of the Ig kappa cDNAs contain sequences belonging to the V kappa 4 gene family. Half of the pre-B cell lines examined also share an 8-kbp BamHI reciprocal product (rp). However, these rp do not involve the same V kappa gene, indicating that conserved BamHI sites exist 3' of some V kappa genes. This rp is also readily detected in DNA from normal adult spleen cells, suggesting that the in vitro rearrangements examined in this study are representative of kappa rearrangements that occur in vivo. We suggest that, unlike the diverse V kappa repertoire expressed by mature B cells, the germline V kappa segments involved in initial rearrangements of the Ig kappa locus are highly restricted, and that an initial V kappa 4 rearrangement is probably followed by other, more random recombination events.     

Human cutaneous T cell lymphoma and leukemia cell lines produce and respond to T cell growth factor

Three cell lines of mature T cell origin derived from patients with cutaneous T cell lymphoma-leukemias (CTCL) were found to be constitutive producers of T cell growth factor (L-TCGF). These are the first reported human cell lines which constitutively produce TCGF. Biologically active TCGF could also be eluted from the surface of these cells using an acid glycine buffer under conditions that maintained cell viability, and subcellular fractionation showed that almost all the TCGF activity was associated with the plasma membrane. Over 30 other human hematopoietic cell lines derived from other disorders were unable to produce TCGF even after induction, and their acid eluates did not contain TCGF activity. L-TCGF from CTCL lines had the same biological activity as TCGF obtained from normal leukocytes (N-TCGF) in that they both supported the long-term growth of normal T cells only after the cells were previously activated by antigen or lectin. Both L-TCGF and N-TCGF increased the rate of proliferation of TCGF-independent and TCGF-dependent CTCL cell lines. The same three factor-independent cell lines that released TCGF adsorbed TCGF in a cell-concentration, time-, and temperature-dependent manner. Since the CTCL cell lines produce TCGF, adsorb TCGF, and increase their proliferative rate in response to TCGF or a related molecule, it is suggested that this endogenously produced factor plays a role in maintaining the abnormal proliferation of these cells in culture as permanently growing cell lines independent of exogenous TCGF. However, this does not mean that this is an essential aspect of neoplastic transformation. Since it is unusual to develop these cell lines in the absence of the continuous need for added TCGF, “autostimulation” may be one of the many unusual variant phenotypic properties sometimes associated with neoplastic cells that gives them a selective advantage for in vitro growth.     

抗原受体基因重排克隆性检测在淋巴瘤诊断中的应用

本研究旨在探讨抗原受体基因重排克隆性检测在淋巴瘤诊断中的意义。收集分析了31例淋巴瘤组织,石蜡包埋切片,HE染色后观察形态,免疫组织化学分析免疫表型。采用BIOMED-2标准化试剂盒检测抗原受体基因重排克隆性。结果表明,31例病例中形态学及免疫组织化学分析疑似T细胞淋巴瘤12例,T细胞反应性增生1例,B细胞淋巴瘤16例,B细胞反应性增生2例。基因重排克隆性检测免疫球蛋白(Ig)阳性率94.44%(17/18),T细胞抗原受体(TCR)阳性率92.31%(12/13),2例阴性。最终12例确诊为T细胞淋巴瘤,B细胞淋巴瘤17例,反应性增生2例,阳性检出率为93%。结论:抗原受体重排基因克隆性分析是诊断淋巴瘤的一种有效辅助手段。     

人白血病细胞株重组激活基因表达及T细胞受体基因重排的检测

背景：淋巴细胞特异性重组激活基因编码的重组激活基因1与重组激活基因2蛋白是参与V（D）J重排机制的重要的重组酶。除参与V（D）J重排以外，近年的研究结果表明重组激活基因介导的转位作用可能与染色体易位及淋巴性恶性肿瘤的发生有关，但迄今尚未有明确定论。目的：检测重组激活基因、DNA修复因子Ku70／Ku80和末端脱氧核苷转移酶mRNA表达以及T细胞受体基因重排在人白血病和淋巴癌细胞株的发生情况。设计：重复测量实验。单位：南方医科大学生物技术学院分子免疫研究所。材料：T淋巴白血病细胞株Jurkat和6T-CEM购自上海细胞生物研究所；T淋巴白血病细胞株Molt-4，皮肤T细胞淋巴癌细胞株HuT102，Burkitt’s淋巴癌细胞株Raji和Daudi以及原髓细胞白血病细胞株HL-60和慢性髓原白血病细胞株K562均由本实验室保存。细胞用含有体积分数0．1胎牛血清的RPMI1640培养基于37℃，体积分数0．05C02条件下培养。方法：实验于2005-10／2006-01在南方医科大学生物技术学院分子免疫研究所完成。采用反转录聚合酶链反应检测重组激活基因1，重组激活基因2，非同源末端连接装置途径中的DNA修复因子Ku70／Ku80。以及末端脱氧核苷转移酶mRNA表达；采用巢式、半巢式聚合酶链反应、连接介导的聚合酶链反应等方法检测T细胞受体重排删除DNA环和T细胞受体B链重组信号序列两端的断裂点。了解参与V（D）J重排过程的基因表达和T细胞受体基因重排中间体的产生情况。主耍观察指标：重组激活基因、DNA修复因子Ku70／Ku80和末端脱氧核苷转移酶mRNA表达以及T细胞受体基因重排在人白血病和淋巴癌细胞株的发生情况。结果：反转录聚合酶链反应检测结果显示：重组激活基因1mRNA在4种T细胞株中均被检测到，在两种B细胞株和两种髓性白血病细胞株中未检测到；重组激活基因2和末端脱氧核苷转移酶mRNA表达仅在Jurkat，Molt-4和6T-CEM3种T细胞株中检测到，但在6T-CEM表达较弱；除HL-60细胞未检测到Ku80表达外，所有细胞株均检测到Ku70和Ku80表达。对4种T细胞株T细胞受体重排中间体检测结果表明：仅在Jurkat细胞中检测到DB2-J132 sjTRECs与DB25’端和3’Rss断点，表明Jurkat细胞发生T细胞受体基因重排。同时发现Jurkat TCR Dβ2-Jβ2重排删除环结合区具有明显的多样性特征。结论：重组激活基因可能与T细胞白血病具有更为密切的关系。Jurkat细胞有可能成为研究重组激活基因与T细胞淋巴性肿瘤的一个潜在的细胞模型。     

人白血病细胞株重组激活基因表达及T细胞受体基因重排的检测

背景:淋巴细胞特异性重组激活基因编码的重组激活基因1与重组激活基因2蛋白是参与V(D)J重排机制的重要的重组酶。除参与V(D)J重排以外,近年的研究结果表明重组激活基因介导的转位作用可能与染色体易位及淋巴性恶性肿瘤的发生有关,但迄今尚未有明确定论。目的:检测重组激活基因、DNA修复因子Ku70/Ku80和末端脱氧核苷转移酶mRNA表达以及T细胞受体基因重排在人白血病和淋巴瘤细胞株的发生情况。设计:重复测量实验。单位:南方医科大学生物技术学院分子免疫研究所。材料:T淋巴白血病细胞株Jurkat和6T-CEM购自上海细胞生物研究所;T淋巴白血病细胞株Molt-4,皮肤T细胞淋巴瘤细胞株HuT102,Burkitt’s淋巴瘤细胞株Raji和Daudi以及原髓细胞白血病细胞株HL-60和慢性髓原白血病细胞株K562均由本实验室保存。细胞用含有体积分数0.1胎牛血清的RPMI1640培养基于37℃,体积分数0.05CO2条件下培养。方法:实验于2005-10/2006-01在南方医科大学生物技术学院分子免疫研究所完成。采用反转录聚合酶链反应检测重组激活基因1,重组激活基因2,非同源末端连接装置途径中的DNA修复因子Ku70/Ku80,以及末端脱氧核苷转移酶mRNA表达;采用巢式、半巢式聚合酶链反应、连接介导的聚合酶链反应等方法检测T细胞受体重排删除DNA环和T细胞受体β链重组信号序列两端的断裂点。了解参与V(D)J重排过程的基因表达和T细胞受体基因重排中间体的产生情况。主要观察指标:重组激活基因、DNA修复因子Ku70/Ku80和末端脱氧核苷转移酶mRNA表达以及T细胞受体基因重排在人白血病和淋巴瘤细胞株的发生情况。结果:反转录聚合酶链反应检测结果显示:重组激活基因1mRNA在4种T细胞株中均被检测到,在两种B细胞株和两种髓性白血病细胞株中未检测到;重组激活基因2和末端脱氧核苷转移酶mRNA表达仅在Jurkat,Molt-4和6T-CEM3种T细胞株中检测到,但在6T-CEM表达较弱;除HL-60细胞未检测到Ku80表达外,所有细胞株均检测到Ku70和Ku80表达。对4种T细胞株T细胞受体重排中间体检测结果表明:仅在Jurkat细胞中检测到Dβ2-Jβ2sjTRECs与Dβ25’端和3’RSS断点,表明Jurkat细胞发生T细胞受体基因重排。同时发现JurkatTCRDβ2-Jβ2重排删除环结合区具有明显的多样性特征。结论:重组激活基因可能与T细胞白血病具有更为密切的关系。Jurkat细胞有可能成为研究重组激活基因与T细胞淋巴性肿瘤的一个潜在的细胞模型。     

IgH基因克隆性重排检测在B细胞淋巴瘤诊断中的应用

目的建立B-NHL临床诊断中IgH基因克隆性重排检测基本方法.方法应用PCR方法,采用IgH FR3A引物,检测了7例B-NHL及4例反应性增生的淋巴结石蜡样本中IgH基因重排情况.结果黏膜相关型边缘区B细胞淋巴瘤（MALT）3例中有2例（2/3）,弥漫大B细胞淋巴瘤2例中2例（2/2）,滤泡淋巴瘤1例中0例（0/1）,套细胞淋巴瘤1例中1例（1/1）检测到IgH基因的克隆性重排.总检测率为5/7（71%）,4例淋巴结反应性增生病例病例均为IgH基因的多克隆性重排.结论PCR-FR3A在鉴别淋巴组织肿瘤性或反应性增生和最终确诊B-NHL上是一项有效的辅助方法.     

Immunoglobulin mu-chain gene rearrangement in a patient with T cell acute lymphoblastic leukemia

A 6-yr-old girl with T cell acute lymphoblastic leukemia (ALL) is described. She had a mediastinal mass and her leukemic cells expressed T cell-associated antigens (Leu 1+, OKT3+, OKT9+, and OKT10+). When we examined genomic DNA from the leukemic cells, we detected Ig mu-chain gene rearrangement with germ-line configuration of light chain genes. As reported recently, detecting Ig gene rearrangement has become an important procedure for further classifying B cell precursor cells. This case, however, suggests that there is also heterogeneity among patients with T cell ALL, not only at the level of cell surface phenotypes, but also at the level of the Ig gene. These findings have major implications when we consider both the ontogenesis of these leukemic cells and the normal differentiation of human lymphocytes.     

Nontargeted stable integration of recombinant adeno-associated virus into human leukemia and lymphoma cell lines as evaluated by fluorescence in situ hybridization

A number of studies on human epithelial cells of varying origin have demonstrated integration of recombinant adeno-associated virus (AAV) vectors into a variety of chromosomes compared with the site-specific integration on chromosome 19 predominantly observed for wild-type (wt) AAV. We have constructed a recombinant AAV (rAAV) vector and tested the integration into hematopoietic cells, using the human acute myeloid leukemia cell line AML5 and the human non-Hodgkin's lymphoma cell line OCI-LY18 as targets. The integration sites were visualized by fluorescence in situ hybridization (FISH). Positive signals were observed for chromosomes 1, 2, 3, 8, 14, 15, 19, and Y. The majority of cells demonstrated integration into one specific site. A minority showed simultaneous integration into more than one chromosome. The frequency of observed integrations was not uniformly distributed among chromosomes; for instance, in AML5 chromosome 2 seemed to be favored. Colony-derived AML5 clones bore unique integration patterns indicating successful transduction of clonogenic progenitor cells with high proliferative potential. The integration was stable and observed for more than 12 months after transduction. FISH has been shown to be a powerful tool for detailed analyses of rAAV integration patterns and can be used to evaluate targets and transduction conditions.     

鼻腔及咽淋巴环恶性淋巴瘤的免疫组化与基因重排检测

对４３例鼻腔及咽淋巴环非何杰金淋巴瘤（Ｎｏｎ－Ｈｏｄｇｋｉｎ＇ｓＬｙｍｐｈｏｍａ，ＮＨＬ）重点进行了免疫表型和基因重排检测，其中鼻腔２５例、咽淋巴环１８例。免疫表型检查结果４３例ＮＨＬ中，ＵＣＨＬ－１和Ｌ２６表达阳性各为２６和７例，１０例无确切免疫表型表达，常有ＵＣＨＬ－１和Ｌ２６阳性细胞同时存在于组织中；ＴＣＲβ和ＩｇＨ基因重排检测：４１例中２８例出现特异性基因重排扩增单带，其中２１例ＴＣＲβ基因重排检测阳性，７例ＩｇＨ阳性，包括１２例ＵＣＨＬ－１和６例Ｌ２６阳性表达者和１０例无确切免疫表型表达者；１例高度反应性增生病例ＴＣＲβ基因重排检测阳性，２例低分化癌和２例淋巴组织高度反应性增生均为阴性。结果表明，免疫表型和基因重排检测有一定互补性；同时讨论了用常规石蜡切片的刮取组织进行基因重排检测的意义。     

WT1基因表达对K562、HL-60细胞增殖作用的研究

目的：探讨ＷＴ１基因反义ＲＮＡ对髓系白血病细胞生长增殖和细胞凋亡的影响及作用机制。方法：用ＷＴ１基因反义ＲＮＡ培养Ｋ５６２、ＨＬ６０细胞，用氮蓝四氮唑盐染色、流式细胞仪检测、逆转录聚合酶链反应等方法观察细胞增殖、凋亡、细胞动力学和基因表达情况。结果：ＷＴ１反义ＲＮＡ可以特异性抑制Ｋ５６２细胞增殖，诱导Ｋ５６２、ＨＬ６０细胞凋亡；对ＨＬ６０细胞的增殖无影响，对ＷＴ１、ｂｃｌ２、ｍｄｍ２基因表达无显著影响。结论：ＷＴ１基因与白血病细胞的增殖、凋亡密切相关，对白血病细胞凋亡的影响与ｐ５３、ｂｃｌ２基因无关。     

非霍奇金淋巴瘤存在IgH基因重组

目的探讨新的生物诊断标记物提高对非霍奇金淋巴瘤(NHL)的诊断准确性及其对于疾病的诊断、疗效评估及病情监控的意义,探讨Ig H基因序列重组作为新型生物诊断标记物的可行性。方法首先进行NHL的二代测序(NGS),然后用PCR技术检测NHL患者血浆特异性DNA片段的重组情况。结果通过对12例NHL患者的肿瘤组织Ig H基因组区域进行平行DNA捕获和测序(Ig Cap),准确定位和检测出Ig H位点重组序列。另外,我们还获得了一名患者的血浆循环DNA重组片段。结论 NHL患者的血浆中可检测到Ig H基因重组,Ig Cap可能成为一种新的针对NHL患者的临床诊断、疗效评估及病情监控的生物诊断标记物。     

T cell receptor alpha-chain gene rearrangements in B-precursor leukemia are in contrast to the findings in T cell acute lymphoblastic leukemia. Comparative study of T cell receptor gene rearrangement in childhood leukemia.

We have analyzed T cell receptor alpha-chain gene configuration using three genomic joining (J) region probes in 64 children with acute lymphoblastic leukemia (ALL). 11 out of 18 T-ALLs were T3 positive; alpha-chain gene rearrangements were demonstrated in only two of 18, indicating that the majority of T-ALLs would have rearrangements involving J alpha segments located upstream of these probes. In contrast, 15 out of 46 B-precursor ALLs showed rearrangements of the alpha-chain gene and J alpha segments located approximately 20-30 kb upstream of the constant region were involved in 13 of these patients. Nine of 15 B-precursor ALLs with rearranged alpha-chain genes had rearrangements of both gamma- and beta-chain genes, whereas the remaining six had no rearrangements of gamma- and beta-chain genes. These findings indicated that alpha-chain gene rearrangement is not specific for T lineage cells and gamma- and/or beta-chain gene rearrangement does not appear essential for alpha-chain gene rearrangement, at least in B-precursor leukemic cells.     

Identification of the human T cell lymphoma virus in B cell lines established from patients with adult T cell leukemia.

Cell lines were established from the peripheral blood of two patients with adult T cell leukemia. In contrast to our previous experience, where all such lines expressed T cell markers, these two cell lines expressed B cell antigens and Ig light chains (kappa on CF-2, lambda on HS). Human T cell lymphoma proviral (HTLV) sequences were demonstrated in both cell lines. Since only a portion of the cells in culture expressed Ig light chains, experiments were carried out to exclude the possibility that the cultures were not a mixture of B and T or non-B cells. Cells that expressed kappa- or lambda-light chains were separated by cell sorting from kappa- or lambda-negative cells and replaced in culture. Light chain negative cells reexpressed light chains after time in culture. After 5-azacytidine treatment of the cell lines, all cells expressed Ig light chains. These studies show that the human retrovirus HTLV, which has been demonstrated to be associated with certain T cell malignancies, can infect B cells or B cell precursors.