CD133-2 (AC141) expression analysis in acute leukemia immunophenotyping in correlation to CD34 and P-glycoprotein

A total of 49 newly diagnosed patients with acute leukemia were studied in order to assess the diagnostic value of clone AC141 of CD133 antibody by flow cytometry. AC141 expression was further compared to CD34 and P-glycoprotein, immunophenotype, morphology and cytogenetic/molecular data. Flow cytometry allowed for the detection of AC141 expression in 42.8% of the patients. A strong correlation with myeloid lineage was observed. All AC141(+) acute myeloid leukemia (AML) cases were of immature morphology and a strong concordance with CD34 expression was found. However, discordant patterns were also observed. Besides, AC141 expression correlated with CD7 in the absence of mature markers (CD14, CD15 and CD64). Similarly to CD34, P-glycoprotein levels were also significantly higher in AC141(+) AML cases. No correlation was found with cytogenetic/molecular data of the patients. In conclusion, membrane expression of AC141, in combination with other antigens, might facilitate a more precise immunologic characterization of acute leukemias and may serve as an alternative to CD34 for purging purposes in selected patients.     

Characterization of Thy-1 (CDw90) expression in CD34+ acute leukemia

Thy-1 (CDw90) is a phosphatidylinositol-anchored cell surface molecule which, when coexpressed with CD34 in normal human bone marrow, identifies a population of immature cells that includes putative hematopoietic stem cells. To date, the characterization of Thy-1 expression has been confined largely to normal tissues and cell lines. In this study, we evaluated the frequency and intensity of Thy-1 expression as defined by reactivity with the anti-Thy-1 antibody 5E10 in 38 cases of CD34+ acute leukemia (21 acute myelogenous leukemia [AML], 8 chronic myelogenous leukemia [CML] in blast crisis, and 9 acute lymphoblastic leukemia [ALL]). In 34 of 38 cases (89%) the CD34+ cells lacked expression of the Thy-1 antigen. High-density Thy-1 expression was found in 1 case of CML in lymphoid blast crisis, and low- density Thy-1 expression was identified on a portion of the leukemic cells in 2 cases of AML with myelodysplastic features, and 1 case of CML in myeloid blast crisis, suggesting a possible correlation between Thy-1 expression and certain instances of stem cell disorders such as CML and AML with dysplastic features. In contrast, the dissociation of Thy-1 and CD34 expression in the majority of acute leukemias studied suggests that the development of these leukemias occurs at a later stage than the hematopoietic stem cell. Characterization of Thy-1 expression in acute leukemia may eventually provide insights into the origin of the disease. In addition, separation of leukemic blasts from normal stem cells based on Thy-1 expression may prove useful in assessing residual disease, as well as in excluding leukemic blasts from stem cell preparations destined for autologous bone marrow or peripheral stem cell transplantation.     

C-kit receptor (CD0117) expression in acute leukemia

The murine monoclonal antibody YB5.B8 (CD117) identifies a transmembrane tyrosine kinase receptor encoded by the human c-kit proto-oncogene. In this study we investigated the expression of c-kit on different types of acute leukemia to determine the degree of specificity and sensitivity of this marker for the myeloid and lymphoid lineages. C-kit was positive in over half of the 115 cases of acute leukemia studied. Overall, two thirds of AML cases expressed c-kit, whereas only one of 23 ALL patients was c-kit positive. C-kit was also positive in 16 of 19 cases of myeloid blast crisis of myeloproliferative disorders and negative in four with a lymphoid phenotype. There was no correlation between c-kit expression and the degree of myeloid differentiation by FAB subtypes or other markers. We conclude that c-kit is a specific marker for the myeloid lineage, which is expressed early during hematopoietic differentiation and can aid the diagnosis of AML in difficult cases. More patients need to be tested to establish whether the expression of c-kit may define AML subgroups of prognostic significance.     

CD133和CD90在肝细胞癌中的表达及其意义

存在于肿瘤组织中的少数具有干细胞性质的细胞群体被称为肿瘤干细胞(CSCs),可促进肿瘤的发生和发展,也是肿瘤耐药性、复发及转移的根源.有报道CD133和CD90可能为肿瘤干细胞表面标志物,但CD133和CD90在肝癌中的表达及其意义报道尚少.本研究采用免疫组织化学方法检测不同肝组织中CD133及CD90蛋白的表达水平,探讨其在肝癌中的表达情况及其与肝癌生物学特性及预后的关系.     

Routine immunophenotyping of acute leukemias (Reply)

Blut (1990) 60: 48–50     

CD133和CD90在肝细胞癌中的表达及其意义

存在于肿瘤组织中的少数具有干细胞性质的细胞群体被称为肿瘤干细胞(CSCs),可促进肿瘤的发生和发展,也是肿瘤耐药性、复发及转移的根源.有报道CD133和CD90可能为肿瘤干细胞表面标志物,但CD133和CD90在肝癌中的表达及其意义报道尚少.本研究采用免疫组织化学方法检测不同肝组织中CD133及CD90蛋白的表达水平,探讨其在肝癌中的表达情况及其与肝癌生物学特性及预后的关系.     

CD116在急性白血病中的表达及临床意义

目的：探讨ＣＤ１１６在急性白血病中的表达及临床意义。方法：对１１４例急性白血病者进行免疫表型及细胞遗传学分析。结果ＣＤ１１６在急性淋巴细胞白轿病（ＡＬＬ）中无阳性表达,而在急性髓性细胞白血病（ＡＭＬ）中阳性表达率为４２．４％;ＣＤ１１６在ＡＭＬ各亚型间出现的频率存在明显差异,阳性率Ｍ５为８３．３％,Ｍ４为４０．０％,Ｍ３和Ｍ２分别为２７．２％和１５．０。２例Ｍ５患者出现染色体＋８异常,伴ＣＤ１１６     

三色荧光标记抗体在急性白血病免疫分型中的应用

目的：探讨多参数分析流式细胞术白血病免疫分型的方法。方法：用自行设计的七组三色荧光标记抗体组合，共含15种抗体，对200例急性白血病患者骨髓或外周血进行流式细胞术免疫分型。结果：应用本组抗体组合可对T-急性淋巴细胞白血病、B-急性淋巴细胞白血病和急性粒细胞白血病-M1-M7患者作出免疫学诊断，并可诊断形态学难以辨认的及一般免疫分型法较难诊断的单核细胞白血病。结论：三色荧光标记抗体组合可用较少的抗体，特异地对急性白血病各亚型进行多参数免疫表型分析，提高了免疫分型的准确性。     

Isolation and characterization of human CD34(-)Lin(-) and CD34(+)Lin(-) hematopoietic stem cells using cell surface markers AC133 and CD7

Recent evidence indicates that human hematopoietic stem cell properties can be found among cells lacking CD34 and lineage commitment markers (CD34(-)Lin(-)). A major barrier in the further characterization of human CD34(-) stem cells is the inability to detect this population using in vitro assays because these cells only demonstrate hematopoietic activity in vivo. Using cell surface markers AC133 and CD7, subfractions were isolated within CD34(-)CD38(-)Lin(-) and CD34(+)CD38(-)Lin(-) cells derived from human cord blood. Although the majority of CD34(-)CD38(-)Lin(-) cells lack AC133 and express CD7, an extremely rare population of AC133(+)CD7(-) cells was identified at a frequency of 0.2%. Surprisingly, these AC133(+)CD7(-) cells were highly enriched for progenitor activity at a frequency equivalent to purified fractions of CD34(+) stem cells, and they were the only subset among the CD34(-)CD38(-)Lin(-) population capable of giving rise to CD34(+) cells in defined liquid cultures. Human cells were detected in the bone marrow of non-obese/severe combined immunodeficiency (NOD/SCID) mice 8 weeks after transplantation of ex vivo-cultured AC133(+)CD7(-) cells isolated from the CD34(-)CD38(-)Lin(-) population, whereas 400-fold greater numbers of the AC133(-)CD7(-) subset had no engraftment ability. These studies provide novel insights into the hierarchical relationship of the human stem cell compartment by identifying a rare population of primitive human CD34(-) cells that are detectable after transplantation in vivo, enriched for in vitro clonogenic capacity, and capable of differentiation into CD34(+) cells. (Blood. 2000;95:2813-2820)     

自配试剂在Coulter流式细胞仪检测急性白血病免疫分型中的应用

目的 分析自配Coulter流式细胞仪试剂在检测急性白血病免疫分型中的应用效果.方法 将自配全血溶解试剂和鞘液及清洗液的理化性质、准确度和精密度以及对检测急性白血病免疫表型抗原的应用效果与原装试剂进行比较分析.结果 自配试剂与原装试剂理化性质基本一致;两种试剂分别测定同一白血病免疫分型标本20次,结果各胞膜抗原批内CV值均＜2%;检测急性白血病免疫分型胞膜和胞浆多种抗原,分别与原装试剂比较,两者差异均无统计学意义(P＞0.05),且检测胞浆抗原cMPO和cCD79a结果均呈高度正相关(r＞0.970).结论 自配Coulter流式细胞仪试剂对白血病免疫分型的检测效果好,可代替原装试剂进行应用并推广.     

The use of the alkaline phosphatase-antialkaline phosphatase technique for immunophenotyping acute myeloid leukemia

The leukemic cells from 31 cases of acute myeloid leukemia were immunophenotyped by the alkaline phosphatase-antialkaline phosphatase (APAAP) technique, using 7 monoclonal antibodies reactive with cells of myeloid origin. We found a good correlation between the results obtained using the APAAP method and indirect immunofluorescence. In most cases, we observed a slight degree of variation in the percentages of reacting cells when comparing the two methods. Nevertheless, taking 20% of cells being immunolabeled as a threshold for defining a case as positive, we found no discrepancies in the final classification of each case. The main advantages of the APAAP method are: (1) its use with routinely prepared peripheral or blood marrow samples, and (2) the possibility of correlating immunological characterization with morphology. Since the results with the APAAP method were comparable with those obtained using indirect immunofluorescence, we suggest that this former technique can complement, and sometimes substitute, other methods of immunological evaluation.     

Prognostic impact of CD200 and CD56 expression in adult acute lymphoblastic leukemia patients

Background: The aim of the study is to determine the prognostic relevance of CD200/ CD56 expression in adult acute lymphoblastic leukemia patients.

Methods: The expression of CD200 and CD56 by blast cells was assessed by flow cytometry before the start of chemotherapy in 70 B-ALL patients.

Results: Positive expression of CD200 was detected in forty-six patients (66%) and CD56 was detected in 7 patients (10%) out of 70 patients, respectively. Only three patients (4.3%) had co-expression for CD200⁺ and CD56⁺. Splenomegaly and thrombocytopenia were frequently observed more in CD200⁺ patients. Increased frequency of CD34⁺ was associated with CD200⁺and CD56⁺ patients. The CD200⁺ and CD56⁺ subgroups of B-ALL patients had inferior OS and disease free survival compared to CD 200^? and CD 56^? patients.

Conclusions: CD200⁺ and/or CD56⁺ positive expression in B-ALL patients at diagnosis is a poor prognostic biomarker. Identification of CD200⁺ and CD56⁺ expression at diagnosis is recommended for a better stratification of adult B-ALL patients.