粒系集落刺激因子对急性髓系白血病细胞的诱导分化作用

观察粒系集落刺激因子对急性髓系白血病细胞诱导分化作用。方法：常规分离３１例急性髓系白血病细胞体外培养７ｄ,然后通过瑞氏染色,非特异性酯酶及氯醋酸萘酚酯酶染色及ＮＢＴ还原试验分别观察了细胞形态学,细胞内酶化学和细胞功能变化,同时采用细胞免疫方染观察细胞膜分化抗原反应。     

Interferon and c-ets-1 genes in the translocation (9;11)(p22;q23) in human acute monocytic leukemia

Gene probes for interferons alpha and beta 1 and v-ets were hybridized to metaphase chromosomes from three patients with acute monocytic leukemia who had a chromosomal translocation, t(9;11)(p22;q23). The break in the short arm of chromosome 9 split the interferon genes, and the interferon-beta 1 gene was translocated to chromosome 11. The c-ets-1 gene was translocated from chromosome 11 to the short arm of chromosome 9 adjacent to the interferon genes. No DNA rearrangement was observed when these probes were hybridized to genomic DNA from leukemic cells of two of the patients. The results suggest that the juxtaposition of the interferon and c-ets-1 genes may be involved in the pathogenesis of human monocytic leukemia.     

Modeling the initiation and progression of human acute leukemia in mice

Our understanding of leukemia development and progression has been hampered by the lack of in vivo models in which disease is initiated from primary human hematopoietic cells. We showed that upon transplantation into immunodeficient mice, primitive human hematopoietic cells expressing a mixed-lineage leukemia (MLL) fusion gene generated myeloid or lymphoid acute leukemias, with features that recapitulated human diseases. Analysis of serially transplanted mice revealed that the disease is sustained by leukemia-initiating cells (L-ICs) that have evolved over time from a primitive cell type with a germline immunoglobulin heavy chain (IgH) gene configuration to a cell type containing rearranged IgH genes. The L-ICs retained both myeloid and lymphoid lineage potential and remained responsive to microenvironmental cues. The properties of these cells provide a biological basis for several clinical hallmarks of MLL leukemias.     

急性髓系白血病患者原发性mdr1基因产物P-170与CD34表达及预后的关系

观察急性髓系白血病患者原发性ｍｄｒ１基因产物Ｐ－１７０与ＣＤ３４抗原表达与预后的关系。方法。常规分离３１例急性髓系白血病细胞,然后分别进行细胞免疫化学检查,观察了细胞膜分化抗原变化和ｍｄｒ１基因产物Ｐ－１７０反应。结论：Ｐ－１７０和ＣＤ３４表达是急性髓系白血病患者对化疗抵抗的标志。     

Translocation and rearrangement of myeloperoxidase gene in acute promyelocytic leukemia

Acute promyelocytic leukemia (subtype M3) is characterized by malignant promyelocytes exhibiting an abundance of abnormally large or aberrant primary granules. Myeloperoxidase (MPO) activity of these azurophilic granules, as assessed by cytochemical staining, is unusually intense. In addition, M3 is universally associated with a chromosomal translocation, t(15;17)(q22;q11.2). In this report, the MPO gene was localized to human chromosome 17 (q12-q21), the region of the breakpoint on chromosome 17 in the t(15;17), by somatic cell hybrid analysis and in situ chromosomal hybridization. By means of MPO complementary DNA clones for in situ hybridization and Southern blot analysis, the effect of this specific translocation on the MPO gene was examined. In all cases of M3 examined, MPO is translocated to chromosome 15. Genomic blot analyses indicate rearrangement of MPO in leukemia cells of two of four cases examined. These findings suggest that MPO may be pivotal in the pathogenesis of acute promyelocytic leukemia.     

慢羽鸡成纤维细胞内源性白血病病毒ev21基因敲除

【目的】探索在慢羽鸡成纤维细胞中敲除ev21基因的可行性,净化鸡群内源性逆转录病毒,同时为快速培育缺失ev21基因的慢羽鸡配套系打下基础。【方法】根据ev21基因序列（KY235336）特点,分别在其5'和3'端各设计2个sgRNA,用于构建4种不同sgRNA的打靶质粒,筛选出在5'和3'端打靶效率较高的sgRNA。然后基于CRISPR/Cas9基因编辑技术对ev21基因进行剪切,并通过同源重组方式以红色荧光蛋白（mCherry）的DNA片段（CAG-mCherry）替换ev21基因,实现对慢羽鸡成纤维细胞内源性白血病病毒ev21基因定点敲除。【结果】在慢羽鸡成纤维细胞中能检测到ev21基因,构建的4种sgRNA（sgRNA1~sgRNA4）均能成功插入对应的打靶质粒中,经嘌呤霉素筛选及T7E1酶切检测,发现转染4种不同sgRNA打靶质粒后慢羽鸡成纤维细胞均有不同程度的死亡,其中又以sgRNA1和sgRNA3的基因敲除效率较高。同时针对同源位点左右同源臂构建表达mCherry的供体质粒,以其转染293T细胞12 h后均能表达出mCherry。以sgRNA1和sgRNA3打靶质粒及供体质粒共同转染慢羽鸡成纤维细胞,观察发现成纤维细胞内的mCherry持续表达,至转染后第30 d通过流式细胞仪分选收集红色荧光阳性成纤维细胞,并提取其总DNA进行PCR鉴定与基因测序,结果显示红色荧光阳性成纤维细胞中有目的片段（CAG-mCherry）插入,即以插入替换方式能实现对ev21基因的敲除。【结论】基于crispr/cas9基因编辑技术的基因敲除方法能成功敲除慢羽鸡成纤维细胞内源性白血病病毒ev21基因,为培育缺失ev21基因的慢羽鸡品系提供技术支持。     

Studies of the human c-myb gene and its product in human acute leukemias

The myb gene is the transforming oncogene of the avian myeloblastosis virus (AMV); its normal cellular homolog, c-myb, is conserved across a broad span of evolution. In humans, c-myb is expressed in malignant hematopoietic cell lines and in primary hematopoietic tumors. Partial complementary DNA clones were generated from blast cells of patients with acute myelogenous leukemia. The sequences of the clones were compared to the c-myb of other species, as well as the v-myb of AMV. In addition, the carboxyl terminal region of human c-myb was placed in an expression vector to obtain protein for the generation of antiserum, which was used to identify the human c-myb gene product. Like v-myb, this protein was found within the nucleus of leukemic cells where it was associated with the nuclear matrix. These studies provide further evidence that c-myb might be involved in human leukemia.     

A model of human acute lymphoblastic leukemia in immune-deficient SCID mice

A human acute lymphoblastic leukemia (ALL) cell line that was transplanted into immune-deficient SCID mice proliferated in the hematopoietic tissues, invaded various organs, and led to the death of the mice. The distribution of leukemic cells in SCID mice was similar to the course of the disease in children. A-1 cells marked with a retrovirus vector showed clonal evolution after the transplant. SCID mice that were injected with bone marrow from three patients with non-T ALL had leukemic cells in their bone marrow and spleen. This in vivo model of human leukemia is an approach to understanding leukemic growth and progression and is a novel system for testing new treatment strategies.     

Molecular analysis of the t(2;14) translocation of childhood chronic lymphocytic leukemia

Two rare cases of chronic lymphocytic leukemia (CLL) in children have been studied; both are associated with a previously undescribed chromosomal translocation [t(2;14) (p13;q32)]. In one patient the translocation was reciprocal and the breakpoint on chromosome 14 occurred just 5' of the C gamma 2 region on the productive immunoglobulin heavy-chain allele. The breakpoint on chromosome 2 does not involve the K locus but lies within an uncharacterized region that coincides with the position of a constitutive fragile site that occurs within normal lymphocytes. Data on the second patient are consistent with these findings and suggest that these cases represent a rare but distinct subgroup of CLL's with a specific cytogenetic change.     

Activating mutations of NOTCH1 in human T cell acute lymphoblastic leukemia

Very rare cases of human T cell acute lymphoblastic leukemia (T-ALL) harbor chromosomal translocations that involve NOTCH1, a gene encoding a transmembrane receptor that regulates normal T cell development. Here, we report that more than 50% of human T-ALLs, including tumors from all major molecular oncogenic subtypes, have activating mutations that involve the extracellular heterodimerization domain and/or the C-terminal PEST domain of NOTCH1. These findings greatly expand the role of activated NOTCH1 in the molecular pathogenesis of human T-ALL and provide a strong rationale for targeted therapies that interfere with NOTCH signaling.     

The role of macrophages in particle translocation from lungs to lymph nodes

Red fluorescent and green fluorescent microspheres were instilled into separate but adjacent areas of dog lung lobes. After 7 days, the tracheobronchial lymph nodes that drained both of the instilled areas contained many macrophages with all red or all green microspheres but rarely both. This indicates that the particles did not translocate passively and that lung macrophages phagocytized the microspheres in the lung and carried them to the tracheobronchial lymph nodes. In addition, two populations of pulmonary alveolar macrophages (PAM's), one that had phagocytized red microspheres in vivo and one that had phagocytized green microspheres, were lavaged from the lungs of dogs, mixed into one population, and instilled back into a previously unexposed lung lobe of the same dogs. As in the first experiment, the tracheobronchial lymph nodes that drained the instilled area contained numerous macrophages with either all red or all green microspheres. This suggested that the instilled PAM's had migrated to the tracheobronchial lymph nodes. Thus, lung macrophages, including PAM's probably play a critical role in the induction of lung immunity and in protection from disease by determining particle translocation.     

Hu-ets-1 and Hu-ets-2 genes are transposed in acute leukemias with (4;11) and (8;21) translocations

Human probes identifying the cellular homologs of the v-ets gene, Hu-ets-1 and Hu-ets-2, and two panels of rodent-human cell hybrids were used to study specific translocations occurring in acute leukemias. The human ets-1 gene was found to translocate from chromosome 11 to 4 in the t(4;11)(q21;23), a translocation characteristic of a subtype of leukemia that represents the expansion of a myeloid/lymphoid precursor cell. Similarly, the human ets-2 gene was found to translocate from chromosome 21 to chromosome 8 in the t(8;21)(q22;q22), a nonrandom translocation commonly found in patients with acute myeloid leukemia with morphology M2 (AML-M2). Both translocations are associated with expression different from the expression in normal lymphoid cells of ets genes, raising the possibility that these genes play a role in the pathogenesis of these leukemias.     

Cytotoxic antibody in normal human serums reactive with tumor cells from acute lymphocytic leukemia

Serums showing complement-dependent cytotoxic reactions to acute lymphocytic leukemia cells were detected in three normal unimmunized subjects. These serums were reactive with tumor cells from 514 (514 tested) acute lymphocytic leukemia patients, and three (12 tested) patients with acute myelocytic leukemia; they did not react with tumor cells from patients with acute monocytic leukemia (two tested), with chronic lymphocytic leukemia (two tested) or with leukolymphosarcoma (two tested); nor did they react with normal lymphocytes from 52 different donors. These reactive serums appear to recognize antigens primarily associated with acute lymphocytic leukemia.     

The human gene encoding GM-CSF is at 5q21-q32, the chromosome region deleted in the 5q- anomaly

Human granulocyte-macrophage colony-stimulating factor (GM-CSF) is a 22,000-dalton glycoprotein that stimulates the growth of myeloid progenitor cells and acts directly on mature neutrophils. A full-length complementary DNA clone encoding human GM-CSF was used as a probe to screen a human genomic library and isolate the gene encoding human GM-CSF. The human GM-CSF gene is approximately 2.5 kilobase pairs in length with at least three intervening sequences. The GM-CSF gene was localized by somatic cell hybrid analysis and in situ hybridization to human chromosome region 5q21-5q32, which is involved in interstitial deletions in the 5q- syndrome and acute myelogenous leukemia. An established, human promyelocytic leukemia cell line, HL60, contains a rearranged, partially deleted GM-CSF allele and a candidate 5q- marker chromosome, indicating that the truncated GM-CSF allele may reside at the rejoining point for the interstitial deletion on the HL60 marker chromosome.     

Inhibition of human acute lymphoblastic leukemia cells by immunotoxins: potentiation by chloroquine

Immunotoxins containing pokeweed antiviral protein and monoclonal antibodies against human T cells or human transferrin receptor efficiently killed acute lymphoblastic leukemia cells. Chloroquine specifically enhanced the rate of protein synthesis inhibition by immunotoxin. Depending on its concentration, chloroquine (10 to 100 micromolar) reduced by up to 65-fold the amount of immunotoxin required to inhibit protein synthesis in the target cells 50 percent.     

omd基因对斑马鱼骨骼矿化的影响

omd基因编码骨调蛋白,可以调控人类骨骼的矿化。目前关于omd基因对鱼类骨骼矿化的作用尚不清楚。为了探究omd基因对鱼类骨骼的影响,调查了omd基因在斑马鱼不同发育阶段和不同组织的表达,并利用CRISPR/Cas9基因编辑技术,成功构建斑马鱼omd基因突变体（omd-/-）。结果表明：omd基因在斑马鱼体内随着发育表达量逐渐增加,在脊柱和肌肉中表达较高;相比野生型斑马鱼,omd-/-品系斑马鱼的骨骼形态和尾部肌肉结构未发现明显变化,脊柱的钙含量下调59.81%;与野生型相比,omd-/-纯合敲除品系斑马鱼平均游泳距离下降33.93%,平均游泳速度下降39.44%,相对静止的时间增加88.26%,游泳能力下降。这些结果表明,omd基因缺失影响斑马鱼脊柱的矿化,并在一定程度上影响了斑马鱼的活动能力。