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Biomedical subjects

M Andreeff

Publications and source records attributed to M Andreeff.

At least 163 records · Page 9Linked to original sources
PubMed1995

Chromosome 17 numerical abnormalities in 55 patients with non-Hodgkin's lymphoma: a fluorescence in situ hybridization study.

Monosomy 17 and structural abnormalities of the short arm of chromosome 17 have been reported to influence prognosis and treatment outcome in patients with non-Hodgkin's lymphoma (NHL). In diffuse large cell lymphoma, these abnormalities were associated with refractoriness to chemotherapy, higher proliferative rate and poor prognosis. We studied the incidence of chromosome 17 abnormalities in 55 patients with NHL by using fluorescence in situ hybridization with a directly conjugated centromeric probe for chromosome 17. Twenty-three patients (42%) were previously untreated. Thirty-four patients (62%) had diffuse large cell lymphoma, 18 (33%) had follicular low-grade lymphoma, one had small lymphocytic lymphoma, one had diffuse mixed cell lymphoma, and one had mantle cell lymphoma. Cells from benign lymphoid hyperplasia were used as controls. Eight patients (15%) had trisomy 17 in 1.2-40.7% of cells and one patient (1.8%) had monosomy 17 in 68.8% of cells. We conclude that monosomy 17 is not common in NHL. Chromosome 17 deletions should be investigated with region-specific probes to determine their clinical relevance in NHL.

Adolescent↗
PubMed1995

Phase II study of interleukin-6 in patients with smoldering relapse of acute myelogenous leukemia.

We gave interleukin-6 (IL-6) to eight patients with AML in first relapse after a median remission of 20.5 weeks and one patient with AML refractory to initial induction therapy. All nine patients had 5-29% blasts in the marrow together with < 5000 circulating blasts/microliter (smoldering disease) with a median platelet count of 19,000/microliters at a median of 7 weeks after initiation of last chemotherapy. The dose was 3.75 micrograms/kg by subcutaneous injection daily for 14 days. None of the nine responded, with response defined as at least a doubling in platelet count to > 30,000/microliters provided neither the marrow nor circulating blast count doubled to > 30% or > 10,000/microliters respectively. Given these data, the likelihood of a 15% response rate in patients whose disease is in smoldering relapse after a short first CR is only 27%, with 15% being the expected average CR rate following chemotherapy in these patients. Rises in platelet count unrelated to spontaneous recovery after prior chemotherapy were seen in three patients and a rise in marrow blast percent in four. Our results suggest that IL-6 might be used in stimulating platelet recovery in AML patients who remain thrombopenic without evidence of leukemia after chemotherapy, unlike our patients whose marrow had 5-29% blasts prior to starting IL-6.

Adult↗
PubMed1995

A 3-day schedule of fludarabine in previously treated chronic lymphocytic leukemia.

This study was undertaken to determine the efficacy and toxicity of a shorter schedule of fludarabine administration (30 mg/m2 i.v. daily for 3 days every 4 weeks) in patients with previously treated chronic lymphocytic leukemia (CLL). Eighty patients with previously treated advanced (Rai III-IV) (54%) or progressive Rai stage 0-II (46%) were treated. The results of this trial were retrospectively compared with those of previous fludarabine trials using different schedules of administration. The complete response (CR), nodular CR and partial response rates were 10, 15 and 21%. The overall response rate (46%) was slightly lower than prior regimens using a 5-day schedule of fludarabine; however, this difference was not significant. Further evaluation by dual-parameter flow cytometry and immunoglobulin gene rearrangement analysis revealed that minimal residual disease was more common in a 3-day schedule. The overall incidence of infections per treatment course (14%) was significantly lower than that observed on the 5-day or weekly regimens (P < 0.001). The incidence of minor, atypical and viral infections were similar. There was no difference in survival in the various trials. In conclusion, a 3-day schedule of fludarabine in previously treated CLL patients was associated with a lower infection rate and similar survival to a 5-day schedule. These data support the use of a 3-day schedule of fludarabine as a single agent and in combination with other active agents.

Adult↗
PubMed1995

A diagnostic workstation for neoplastic bone marrow diseases: evaluation on 526 cases.

The diagnostic accuracy of a workstation for neoplastic bone marrow pathology was evaluated on 526 cases from two institutions. The workstation consists of knowledge-based systems for peripheral blood analysis, flow cytometry immunophenotyping, and bone marrow morphology, linked together by a relational database. The "gold standard" diagnosis was established by complete agreement among three hematopathologists after independent review of the data from each case. The workstation's diagnosis agreed with the "gold standard" in 515 cases (97.9%). In six of the 11 diagnostic errors, the bone marrow module could not reach a final diagnosis. The five misclassifications would not have resulted in a change of therapy for the patient. The institutional diagnosis of record agreed with the gold standard in 462 cases (87.8%). The results indicate that the workstation is capable of high-quality, reproducible, multiparameter interpretive reporting.

Acute Disease↗
PubMed1995

High remission rate, short remission duration in patients with refractory anemia with excess blasts (RAEB) in transformation (RAEB-t) given acute myelogenous leukemia (AML)-type chemotherapy in combination with granulocyte-CSF (G-CSF).

A study was made to determine CR rate, response duration and survival in patients with RAEB or RAEB-t given AML-type chemotherapy, in particular the newer agents idarubicin and fludarabine. Eighty-five adults (58 RAEB-t, 27 RAEB) received either IA (idarubicin 12 mg/m2 daily on days 1-3, ara-C 1.5 g/m2 daily on days 1-4 CI), FA (fludarabine 30 mg/m2 daily on days 1-5, ara-C 2 g/m2 daily on days 1-5) or FLAG (FA + G-CSF 400 micrograms/m2 daily from day-1 until CR). IA was given exclusively to patients with better prognosis (as assessed by pretreatment karyotype), while FA and FLAG were given first to patients with worse and then to those with better prognosis. In remission, patients received lower doses of the same regimens for 6-12 months. The 85 patients comprise the largest reported series of RAEB or RAEB-t patients given AML-type chemotherapy. Their median age was 61 years, 33% had chromosome 5 or 7 abnormalities (-5/-7), and 55% were treated in laminar air flow rooms. The CR rate was 66%. While rates were highest in younger patients with a normal karyotype, CR rates in excess of 50% were also obtained in patients over age 60 (27/47; 57%) and in patients with -5/-7 (17/29; 59%). In 11 of the 14 cytogenetically abnormal patients in whom cytogenetic analysis was repeated at the time of CR, only normal metaphases were found. In the remaining 3 the number of abnormal metaphases was substantially reduced. However, the probability of continued CR was low (e.g. 452 +/- 0.08 at 12 months), and the only patients alive in CR beyond two years were patients under age 60 without -5/-7 and with RAEB-t. Survival probability was 0.35 +/- 0.05 at one year. Eight of 56 patients died in CR. While current AML-type chemotherapy can produce higher CR rates than is perhaps usually appreciated, in some patients with RAEB or RAEB-t (e.g. older patients with -5/-7) the brevity of the remissions and the risk entailed suggest that new post-remission therapies are needed to make this approach generally worthwhile.

Adult↗
PubMed1995

PML/RARalpha, a fusion protein in acute promyelocytic leukemia, prevents growth factor withdrawal-induced apoptosis in TF-1 cells.

A unique mRNA produced by the t(15;17) (q22-24;q11-21) translocation in the leukemic cells of acute promyelocytic leukemia patients encodes a chimeric protein, PML/RARalpha, which is formed by the fusion of the retinoic acid receptor alpha (RARalpha) and the promyelocytic locus gene (PML). This translocation is often the only visible karyotypic aberration present which is detected in almost 100% of acute promyelocytic leukemia patients. As an initial step to study the role of PML/RARalpha in leukemogenesis, we attempted to express the fusion protein in hematopoietic cells through retrovirus-mediated gene transfer of the retroviral vector, pGPRCHT, which contains the PML/RARalpha cDNA. Transduction of the PML/RARalpha cDNA fragment used in this vector, which extends from the position 31 bp to the position 2638 bp in a transcription unit driven by the Moloney murine sarcoma virus LTR, was found to abrogate the growth factor dependence of TF-1 cells. In addition, introduction of PML/RARalpha into TF-1 cells can protect these cells from the apoptosis usually induced in TF-1 cells by growth factor withdrawal, as measured by three assays for apoptosis: morphology, DNA ladder formation, and end labeling of nicked DNA with fluorescent-conjugated nucleotide precursors followed by a fluorescence-activated cell sorting assay. These data suggest that the PML/RARalpha fusion protein may inhibit programmed cell death in myeloid cells.

Apoptosis↗
PubMed1994

A knowledge-based system for the interpretation of flow cytometry data in leukemias and lymphomas.

Flow cytometry immunophenotyping and analysis of DNA ploidy and proliferative activity have become extremely helpful techniques for diagnosing and subclassifying hematopoietic cell populations in a modern, full-service hematopathology laboratory. The number of physicians with special training in the interpretation of these studies is limited. A knowledge-based computer system has been designed to aid in the interpretation of immunophenotyping and DNA flow cytometry results in hematopoietic disease. The system, known as "Professor Fidelio," is a heuristic classification system that reasons on the basis of defined diagnostic patterns. In this study, Fidelio was tested as a stand-alone system on 366 specimens from two large tertiary medical centers. Fidelio's interpretation was considered to be appropriate in all cases. In 300 of 366 (82%) specimens, the system's interpretation agreed with the diagnosis of record. Many of the disagreements could be traced to errors in the recording of the original diagnosis and minor differences in diagnostic criteria between Fidelio's knowledge base and the criteria in use at the medical centers. When used in a stand-alone mode, Fidelio's interpretation was less specific than the diagnosis of record in certain lymphoproliferative disorders that require morphologic information for subclassification. Professor Fidelio is one module in a workstation for the diagnostic hematology laboratory. This workstation is designed for interpretive reporting, education, and database functions for clinical research. Clinical and morphologic information are shared between Fidelio and the other modules for peripheral blood analysis, bone marrow morphology, and lymph node interpretation by means of a relational database. The system will be useful in hospitals that lack individuals specially trained in flow cytometry.(ABSTRACT TRUNCATED AT 250 WORDS)

Artificial Intelligence↗
PubMed1994

Flow cytometric determination of the multidrug-resistant phenotype in acute leukemia.

Expression of the multidrug-resistant (MDR) phenotype was investigated in acute leukemia using a monoclonal antibody (HYB-241) directed against a cell surface epitope of the 180 kd P-glycoprotein (gp180) by flow cytometric analysis of clinical samples. Samples from sixty-four patients were tested (37 with acute myelocytic leukemia, 20 with acute lymphocytic leukemia, and 7 with blastic chronic myelocytic leukemia). A D value (derived from Kolmogorov-Smirnov test) greater than 0.15 was considered positive (+). Eight of 32 newly diagnosed patients were positive for gp180 compared with 22 of 32 relapsed/refractory (R/R) patients (P < 0.001). Of the new patients, vinca/anthracycline-based induction therapy failed in 3/6 gp180(+) and 5/18 gp180(-) patients. In the R/R group, 15/16 gp180(+) and 3/6 gp180(-) patients failed to achieve complete remission (P < 0.05). In vitro drug accumulation studies performed with verapamil failed to show a correlation with clinical response. However, in a subset of patients, a striking correlation (r = .97, P = .001) was noted between the presence of gp180 as determined by the D value and the functional activity of the P-glycoprotein as expressed by increased daunorubicin accumulation in the presence of verapamil. The results suggest that 1) newly diagnosed patients can express gp180, 2) P-glycoprotein is expressed in 69% of R/R patients, 3) response in R/R patients is effected by the presence of gp180, and 4) expression of gp180 is highly correlated with its function as a drug-efflux pump in a subset of the patients studied. The complexity of clinical drug resistance is underscored by the finding that the MDR model is not applicable to all cases. In such instances, other mechanisms may play a predominant role.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Retinoic acid-induced expression of CD38 antigen in myeloid cells is mediated through retinoic acid receptor-alpha.

CD38 is a leukocyte differentiation antigen that has been thought to be a phenotypic marker of different subpopulations of T- and B-lymphocytes. In myeloid cells, CD38 is expressed during early stages of differentiation. Virtually no information is available on regulation and functions of CD38. Recently we reported that all-trans-retinoic acid (ATRA) is a potent and highly specific inducer of CD38 expression in human promyelocytic leukemia cells. Here we report that ATRA-induced expression of CD38 antigen in myeloid cells is mediated through retinoic acid-alpha receptor (RAR alpha). ATRA failed to induce CD38 expression in a mutant subclone of the HL-60 myeloid leukemia cell line (designated HL-60R) that is relatively resistant to ATRA-induced granulocytic differentiation. Retroviral vector-mediated transduction of RA receptor (RAR alpha) into this HL-60R subclone completely restored the sensitivity of these cells to ATRA in terms of their ability to express CD38. In contrast, CD38 expression was not inducible by ATRA in HL-60R cells, transfected with a functional RAR beta, RAR gamma, or RXR alpha receptor. Induction of CD38 in acute promyelocytic and acute myeloblastic leukemia cells was independent of ATRA-induced cytodifferentiation. Following culture with ATRA, increased CD38 protein levels were also observed in normal CD34+ bone marrow cells, but not on normal circulating granulocytes. From these results, we conclude that CD38 is ATRA inducible in myeloid leukemia cells and normal CD34+ bone marrow cells. This effect is independent of differentiation and is mediated by RAR alpha in HL-60 cells, suggesting a similar role for RAR alpha in CD38 expression in other hematopoietic cells.

ADP-ribosyl Cyclase↗
PubMed1994

Lack of effect of 2-chlorodeoxyadenosine therapy in patients with chronic lymphocytic leukemia refractory to fludarabine therapy.

BACKGROUND: Fludarabine and 2-chlorodeoxyadenosine are nucleoside analogues that have proved effective in patients with chronic lymphocytic leukemia (CLL). Although their mechanism of action is thought to be similar, a small number of patients who do not respond to fludarabine do respond to 2-chlorodeoxyadenosine. The extent to which 2-chlorodeoxyadenosine is effective in patients who do not respond to fludarabine is not known, however. METHODS: We treated 28 patients with CLL refractory to fludarabine therapy with a continuous infusion of 2-chlorodeoxyadenosine at a daily dose of 4 mg per square meter of body-surface area for seven days. The treatment could be repeated monthly. The number of treatments ranged from one to five; patients who responded continued to receive treatment until the maximal response was achieved. RESULTS: Two patients (7 percent) had partial remissions, but no patients had complete remissions. One other patient had a substantial response but had residual thrombocytopenia. The rate of response in most affected organs was 20 percent, but anemia or thrombocytopenia rarely improved. Myelosuppression was frequent, and 65 percent of the courses of 2-chlorodeoxyadenosine therapy were accompanied by febrile episodes or infections. Ten patients died within 60 days of starting therapy with 2-chlorodeoxyadenosine; eight deaths were related to infection. The median platelet count at the start of 2-chlorodeoxyadenosine therapy in these 10 patients was 24,000 per cubic millimeter, as compared with 109,000 per cubic millimeter in the other 18 patients. Five patients were alive after a median follow-up of 24 months. CONCLUSIONS: Patients with advanced CLL refractory to fludarabine therapy are unlikely to benefit from treatment with 2-chlorodeoxyadenosine. Although 20 percent of the patients have some response, thrombocytopenia and anemia are rarely corrected and may be made worse by 2-chlorodeoxyadenosine therapy.

Adult↗
PubMed1994

Polysomy of chromosome 12 in 60 patients with non-Hodgkin's lymphoma assessed by fluorescence in situ hybridization: differences between follicular and diffuse large cell lymphoma.

Sixty consecutive evaluable specimens from patients with non-Hodgkin's lymphoma (NHL) were studied for the incidence of polysomy of chromosome 12 by fluorescence in situ hybridization (FISH) with probes for the repetitive DNA sequence in the centromeric region of chromosome 12. Thirty-six samples were from follicular lymphomas (FLs), and twenty-four were from diffuse large cell lymphomas (DLCLs). Fifty-two specimens (86%) were obtained by fine-needle aspiration of a diseased node, seven (11.6%) were from involved bone marrows, and one specimen was from a pleural effusion. Twelve of the thirty-six (33%) cases with FL had trisomy 12 in 3-41% of the cells (median, 10%) (normal controls had three signals in 1.4 +/- 0.7% of cells). Trisomy 12 was found in 62% of the patients who had had FL for more than 5 years. Nine of the twenty-four cases (37%) with DLCL had more than two copies of chromosome 12 in 4-92% of the cells (median, 78%), and all nine cases were of B-cell phenotype. Unlike FL cells, some DLCL cells had 4-6 copies of chromosome 12. In previously untreated patients, 54% of DLCLs and 26% of FLs had subpopulations of cells containing more than two copies of chromosome 12 (P = 0.04). Only 2/7 cases of DLCL with polysomy 12 had rearrangement of the BCL2 gene, indicating that the majority of DLCL cases with polysomy 12 did not result from histologic transformation of low grade follicular lymphomas. These data demonstrate that FISH of interphase cells is a sensitive method for detecting numerical abnormalities of chromosome 12 in NHL.(ABSTRACT TRUNCATED AT 250 WORDS)

Aneuploidy↗
PubMed1994

High incidence of monosomy 18 in lymphoid malignancies that have bone marrow and peripheral blood involvement.

We studied the incidence of numerical chromosome 18 abnormalities in 107 patients with lymphoid malignancies by fluorescence in situ hybridization (FISH) using a directly conjugated centromeric probe for chromosome 18. Samples were obtained by fine needle aspiration of diseased nodes, bone marrows or peripheral blood. Monosomy 18 was more common in chronic lymphocytic leukemia (43%), small lymphocytic lymphoma (28%), and follicular lymphomas (12.5%) than in diffuse lymphomas (5.3%; p < 0.01). Monosomy 18 was detected in 9.7-17.1% of the cells in non-Hodgkin's lymphoma (NHL) (background, 5.4%; 99% CI, 4.2%-6.6%) and in 8%-16.7% (median, 10%) of the cells in (CLL) (background, 3.4%; 99% CI, 2.5%-4.3%). All patients with monosomy 18 were found to have bone marrow involvement. Of all untreated patients who had disease involving the bone marrow, 32% were found to have monosomy 18. Trisomy 18 was detected in 3.6%-48.2% of the cells in NHL (background, 0.9%; 99% CI, 0.2%-1.6%) and was most common in diffuse large-cell lymphoma (34%) and follicular lymphomas (31%). None of the patients with small lymphocytic lymphoma or chronic lymphocytic leukemia had trisomy 18. There was no correlation between trisomy 18 and response to treatment or clinical presentation. In this study, monosomy 18 was observed frequently in patients with lymphoid malignancies that involve the bone marrow and peripheral blood. Our data suggest that important gene(s) located on chromosome 18 may be involved in homing of the malignant lymphocytes to the bone marrow and peripheral blood.

Adult↗
PubMed1994

Use of granulocyte colony-stimulating factor before, during, and after fludarabine plus cytarabine induction therapy of newly diagnosed acute myelogenous leukemia or myelodysplastic syndromes: comparison with fludarabine plus cytarabine without granulocyte colony-stimulating factor.

PURPOSE: To determine whether granulocyte colony-stimulating factor (G-CSF) administered before, during, and after fludarabine plus cytarabine (ara-C; FA) chemotherapy affected complete response (CR) rate, infection rate, blood count recovery, or survival in patients with newly diagnosed acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS). PATIENTS AND METHODS: A total of 112 patients with newly diagnosed AML (n = 69) or MDS (n = 43) received G-CSF 400 micrograms/m2/d 1 day before (presenting WBC count < 50,000/microL) and/or during (all patients) fludarabine 30 mg/m2/d and ara-C 2 g/m2/d for 5 days (FLAG). G-CSF continued until a CR was achieved. Results were compared with those in 85 newly diagnosed patients (54 AML, 31 MDS) previously treated with FA without G-CSF. RESULTS: Patients in both groups were relatively old (median age of all patients, 63 years), and were likely to have prognostically unfavorable cytogenetic abnormalities (36% had abnormalities of chromosomes 5 and 7 [-5/-7]). G-CSF accelerated recovery to > or = 1,000 neutrophils (P < .0001; median, 34 days for FA, 21 days for FLAG), but logistic regression provided no evidence that the CR rate was higher with FLAG than with FA (P = .50), with unadjusted CR rates of 63% and 53%, respectively. This may reflect relatively high rates of death before neutrophil recovery in both groups. Rates of infection were similar in both groups. The follow-up duration in remission is short, and much of these data remain censored. To date, survival is similar with FA and FLAG. CONCLUSION: On average, G-CSF before, during, and after FA had no effect on CR or infection rates in this population, in which elderly patients and poor prognostic factors were prevalent. The use of FA and laminar airflow rooms rather than more usual therapy needs to be considered when analyzing the results.

Aged↗
PubMed1994

Granulocyte-colony stimulating factor, granulocyte-macrophage colony stimulating factor, PIXY-321, stem cell factor, interleukin-3, and interleukin-7: receptor binding and effects on clonogenic proliferation in acute lymphoblastic leukemia.

Cytokines are frequently used after chemotherapy of leukemias and solid tumors to augment recovery of normal hematopoiesis. While the regulation of normal and leukemic myelopoiesis is well investigated, little is known about effects of cytokines on growth and differentiation of lymphoblastic leukemia. In this study, we investigated the expression of receptors for G-CSF, GM-CSF, SCF, IL-3, and IL-7 on acute lymphoblastic leukemia (ALL) blasts and the effects of these growth factors (GF) on ALL blast colony formation. The binding of fluorescence-tagged cytokines to receptors on ALL blasts was studied by flow-cytometry in 27 cases of ALL (24 precursor B-ALL, 3 T-ALL). Receptor-binding for myeloid-associated GF was observed in the majority of precursor B-ALL (G-CSF = 100%, GM-CSF = 65%, IL-3 = 83%, SCF = 74%), but not in T-ALL. Binding of labelled IL-7 was detected in both precursor B- (92%) and T-ALL (100%). The presence of receptors for SCF in ALL was confirmed by polymerase chain reaction for c-kit mRNA in 19/21 cases tested. Expression of receptors for G-CSF, GM-CSF, IL-3, and SCF was not associated with expression of myeloid antigens, or with specific cytogenetic abnormalities. The effects of these GF on clonogenic cells were tested in the ALL blast colony assay and varied between samples, but all cytokines were able to increase clonogenic growth. The GM-CSF/IL-3 fusion molecule PIXY-321 was most effective in promoting colony growth. In some cases inhibition of colony formation was found. We conclude that ALL blast cells have receptors not only for IL-7, but also for G-CSF, GM-CSF, SCF, and IL-3. ALL precursors can respond to these GF with changes in their clonogenic growth indicating the presence of functional receptors. Results may have implications for therapeutic approaches combining cytokines and chemotherapy.

Adolescent↗
PubMed1994

Combination of hematopoietic growth factors containing IL-3 induce acute myeloid leukemia cell sensitization to cycle specific and cycle non-specific drugs.

Laboratory studies have suggested that hematopoietic growth factors (GF), combined with cytosine-arabinoside (Ara-C) can enhance cytotoxic effects of this agent against acute myeloid leukemia (AML) cells. While clinical trials based on this growth factor/chemotherapy combination (GF/CT) are progressing with discordant results, further information regarding the underlying mechanisms have been reported supporting this rationale and requiring additional investigation. To assess the role of cytokinetic changes in the GF/CT strategy and to evaluate if chemotherapeutic agents regimens other than Ara-C, when combined with GF, can enhance their cytotoxic effects, we have primed AML blasts with two cytokine combinations and then exposed these cells to the S-phase specific agent Ara-C as well as to the phase non-specific drug daunorubicin (DNR) and to the alkylating agent 4-hydroperoxycyclophosphamide (4-HC). The two cytokine combinations used for priming AML blasts were: (i) interleukin-3 (IL-3) + granulocyte-macrophage colony-stimulating factor (GM-CSF) + granulocyte colony-stimulating factor (G-CSF); and (ii) GM + G-CSF. Cytokinetic analysis in ten AML samples and clonogenic growth of leukemic colonies (CFU-L) in methylcellulose were used to detect proliferative and cytotoxic effects on AML samples. We report that in AML clonogenic cell growth can be stimulated by cytokines in 50% of the samples (4/8), and that Ara-C sensitization clearly occurs in two out of these four samples. Among the different cytokine combinations tested, the one containing IL-3 was the most effective through a cytokinetic mechanism consistent with recruitment (averaged G0 decrease p = 0.04; S-phase increase p = 0.005). Furthermore we observed increased cytotoxicity also to the phase non-specific drugs DNR and 4-HC, which may be mediated by other mechanisms recently described. We conclude that GF/CT combinations may also be beneficial in regimens containing drugs other than Ara-C, used for AML treatment, including bone marrow transplantation conditioning regimens.

Antineoplastic Agents↗
PubMed1994

Large-scale preparation of highly purified, frozen/thawed CD34+, HLA-DR- hematopoietic progenitor cells by sequential immunoadsorption (CEPRATE SC) and fluorescence-activated cell sorting: implications for gene transduction and/or transplantation.

The purification of early hematopoietic progenitor cells for autologous transplantation is based on two rationales: (1) elimination of clonogenic tumor cells, and/or (2) gene transfer into indefinitely self-replicating hematopoietic stem cells. Primitive CD34+ stem cells can be separated from more mature stem cells, or probably from clonogenic tumor cells, by differences in HLA-DR surface antigen expression. The objective of this study was to establish a large-scale technique for purification of CD34+, DR- progenitor cells from a large volume marrow harvest. In five different experiments, CD34+ cells were purified to between 76% and 91% by avidin-biotin immunoadsorption (CEPRATE SC) as a first step. This was followed by fluorescence-activated cell sorting to separate DR+ and DR- cells, which resulted in the generation of between 1.75 and 11.3 x 10(5) CD34+, DR- cells. The purity of DR- cells increased from between 0.5% and 4.3% in the immuno-adsorbed fraction up to 99% in the DR- sorted fraction. As shown in a single experiment, the purity of CD34+, DR- cells immediately after thawing increased from 0.01% to 94.3% while losing 99% of those early progenitor cells during the multistep purification procedure. We were able to physically separate one CD34+, DR- cell from up to 8000 nucleated cells in the prepurified cell suspension. One million highly purified CD34+, DR- progenitor cells is potentially an adequate cell dose for autologous transplantation equivalent to what is contained in an unselected and functioning marrow autograft.

Antigens, CD↗
PubMed1994

Flow cytometry. Clinical and research applications in hematologic malignancies.

Flow cytometric immunophenotyping has become an essential component of the diagnostic workup of leukemias and lymphomas, complementing morphology by providing information on the lineage and differentiation. It also has value in monitoring disease after therapy and in detecting minimal residual disease. This article reviews recent developments in the clinical and research applications of flow cytometry in the study of hematologic malignancies.

Flow Cytometry↗