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Results for “Granulocyte Precursor Cells”

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PubMed1997

[New developments in understanding the compensatory hematological reactions and their outcomes in local fractionated therapeutic gamma irradiation].

We have carried out a study of the bone marrow status in both irradiated and non-irradiated zones of 56 patients with stage I-II Hodgkin's disease in complete 9-12 (33 patients, group 1) and 18-23 (23 patients, group 2) year remission after therapeutic irradiation of the supradiaphragmatic lymphatic collectors at a dose of 40 Gy with irradiation of the spleen (33 patients) or splenectomy (23 patients). The total count of myelokaryocytes, myelogram, a relative and absolute content of lymphoid cells, immature granulocytes and elements of erythroid series were calculated in the aspirates from the exposed to radiotherapy sternum and non-irradiated upper portion of the ileum. The number of granulocyte-macrophage (CFU-GM) and stromal (CFU-F) precursor cells were defined using in vitro culture technique. There was a complete annihilation of the bone marrow in the irradiated zones, when the dose exceeded 35 Gy in 3-4 weeks. The concentration of myelokaryocytes, immature granulocytes, erythronormoblasts, CFU-GM, CFU-F in non-exposed bone marrow were significantly lower in all patients of group 2 than in normal subjects and in group 1 patients. Absolute lymphoid count in patients with 18-23 year remission was found to be normal but was considerably reduced in comparison to patients of group 1. These changes may be the result of the previous hyperactivity of the non-irradiated bone marrow which could be a cause of stem cell compartment depletion. The differential calculation of compact and diffuse subpopulations of CFU-F revealed a significant reduction of compact colony-forming CFU-F in both irradiated and unexposed bone marrow. Almost all the stromal precursor cells from irradiated zone formed diffuse colonies in cultures. These results confirm experimental data concerning greater radiosensitivity and proliferative potential of CFU-F, forming compact colonies versus diffuse colony-forming CFU-F. Aplasia of the irradiated bone marrow and hypoplasia of the non-irradiated bone marrow 18-23 years after radiotherapy completion coexisted with normal circulating CFU-GM and granulocyte blood count suggesting a compensatory mechanism involving a mitotic amplification between the progenitor cell and the final differentiated cell.

Adult↗

PubMed1983

Interactions of porcine alveolar macrophages and bone marrow cells with African swine fever virus and virus-infected cells.

Virus yields from porcine alveolar macrophages (AM) infected with African swine fever virus (ASFV) were greater and were achieved more rapidly, when inoculated at a high multiplicity of infection (MOI) than at low MOI. The difference was related to a lower percentage of cells becoming infected after low MOI inoculation. The reduced yields after low MOI were not caused by prolongation of the culture time, by bacterial endotoxins or by production of inhibitory substances by infected AM. Virus-infected AM were not susceptible to lysis in antibody-dependent cell mediated cytotoxicity (ADCC) assays and this was apparently due to a paucity of viral antigen expressed on the cell surface. Uninfected AM did not act as effectors in ADCC. Porcine bone marrow (PBM) cells were effective in mediation of ADCC and their activity was reduced after ASFV infection. Cells separated into adherent and non-adherent populations, depleted by carbonyl iron treatment or separated by Ficoll-Hypaque centrifugation, all showed effector activity in ADCC. The effector cells were not mature neutrophils or lymphocytes and were probably granulocytic precursors.

African Swine Fever Virus↗

PubMed1985

A quantitative assay for mouse granulocyte (CFU-g) and macrophage (CFU-m) precursors using plasma clots.

Cytochemical procedures were used to identify and quantitate granulocyte and macrophage precursors from mouse bone marrow cells in plasma clot cultures. Excellent clonal morphology and cellular enzyme activity were obtained when using plasma clots as the support matrix and buffered formalin acetone as the fixative. For cytochemical identification, naphthol AS acetate esterase staining was used for macrophages and peroxidase for granulocytes. These enzyme properties were confirmed by inactivation studies with a variety of inhibitors, group specific chemical modifications, and pinocytotic affinity for horseradish peroxidase. When mouse bone marrow cells (3 X 10(4) cells/dish) were cultured in plasma clots with human placental or L-cell-conditioned medium, 70 to 110 colonies were produced. Both pure granulocyte (CFU-g) and pure macrophage colonies (CFU-m) were observed, but approximately 5% of the total colony number was composed of mixed granulocyte/macrophage colonies (CFU-gm). The number of plated cells correlated strongly with the colony number (0.990 less than r less than 0.999).

Animals↗

PubMed1996

Development, differentiation, and phenotypic heterogeneity of murine tissue macrophages.

In murine ontogeny, macrophage precursor cells develop in the yolk sac and fetal liver. Primitive macrophages also appear in the yolk sac, migrate to various tissues, and differentiate into several fetal macrophage populations. Because the development of the monocytic cell lineage is incomplete in the early stage of fetal hematopoiesis, primitive/fetal macrophages are considered to originate from granulocyte-macrophage colony forming cells or earlier macrophage precursors, bypassing the early monocytic cell series. In adult mice rendered severely monocytopenic by administration of strontium-89, resident macrophages are maintained by self-renewal. In contrast, administration of liposome-encapsulated dichloromethylene diphosphonate (clodronate) results in the elimination of various tissue macrophage populations. The repopulation of affected macrophages is dependent on the increase of precursors in the liver and spleen during the period of macrophage depletion. Such precursors reconstitute heterogeneous macrophage subpopulations. In mice homozygous for the osteopetrosis (op) mutation, the absence of macrophage colony-stimulating factor (M-CSF) activity results in a deficiency of monocytes and monocyte-derived macrophages. However, immature macrophages are present in various tissues. Administration of M-CSF to op/op mice induces the increased proliferative capacity and the morphological maturation of macrophages. However, the responses of individual tissue macrophage subpopulations to M-CSF are different. These results indicate that macrophage development, differentiation, and proliferation are regulated by the tissue microenvironment including the in situ production of macrophage growth factors in both fetal and adult life.

Animals↗

PubMed1992

[Clonal proliferation of less mature granulocytic precursors (CFU-dG) under the influence of neoplastic B lymphocytes in low grade non-hodgkin's lymphomas].

The effect of peripheral blood lymphoma B cells from low grade malignancy non-Hodgkin's lymphoma patients (Kiel classification: lymphocytic, centrocytic, centroblastic-centrocytic lymphomas) on clonal growth of normal marrow granulocytic precursors (CFU-dG) was studied. Using in vivo diffusion chamber culture method it was shown that all the tested lymphoma cells enhanced the CFU-dG growth by releasing humoral factor(s). The effect of stimulation was cell-concentration and cell-source dependent. The colony stimulating activity produced by centrocytic lymphoma cells had higher potency than that released by centroblastic-centrocytic lymphoma cells, whereas lymphocytic lymphoma cells showed the lowest ability to generate the CFU-dG growth-promoting activity (p < 0.01). It was shown that the CFU-dG growth enhancing effect was independent of marrow-derived macrophages and T lymphocytes (p > 0.05). Normal peripheral blood B lymphocytes used as a control did not show any substantial effect on the granulocytic precursors proliferation.

B-Lymphocytes↗

PubMed1992

Granulocyte-macrophage colony-stimulating factor (GM-CSF) treatment of clozapine-induced agranulocytosis: a case report.

BACKGROUND: Granulocytopenia and agranulocytosis are severe side effects of clozapine therapy. Even if these side effects are detected early and if clozapine is discontinued, patients suffering from agranulocytosis are extremely endangered by infectious diseases for up to 3 to 4 weeks until hematologic recovery. Therefore, any treatment that reduces this critical time span would decrease the risks of clozapine treatment. METHOD: The case of a patient in whom severe agranulocytosis developed after 7 weeks of clozapine treatment is presented. RESULTS: After clozapine discontinuation, treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF), a glycoprotein that has been shown to stimulate the proliferation of precursor cells in the bone marrow and their differentiation into granulocytes and macrophages, was initiated. Under GM-CSF treatment, total granulocyte count rose from 63/cu mm to a value greater than 1500/cu mm within 5 days without complications or major side effects. CONCLUSION: This case report suggests that treatment with GM-CSF may lower the risks associated with clozapine-induced agranulocytosis and therefore may indirectly improve the safety of clozapine therapy.

Adult↗

PubMed1992

Binding of fluorescein-labeled anaphylatoxin C5a to human peripheral blood, spleen, and bone marrow leukocytes.

The expression of C5a receptors (C5aR) on human leukocytes was evaluated by flow cytometry using fluorescein-labeled human C5a (C5a-F). Granulocytes and CD14+ mononuclear cells (MNL) but not CD3+, CD20+, CD16+, CD56+, or CD11b+ lymphocytes in peripheral blood and spleen bound C5a-F. C5a-F binding was saturable and inhibitable by anti-C5a monoclonal antibody (MoAb) C17/5 or unlabeled C5a. During hemodialysis, which led to the generation of C5a, only granulocytes and monocytes increased their expression of the adhesion molecule CD11b (CR3). In vitro, C5a induced an increase of CR3 and p 150/95 (CD11c/CR4) only on myeloid cells. However, treatment of leukocytes with phorbol 12-myristate 13 acetate increased CR3 and CR4 expression on both myeloid cells and a lymphocyte subpopulation. Stimulation of MNL in mixed lymphocyte cultures or by treatment with conditioned medium or with IFN-gamma did not induce binding sites for C5aR on lymphocytes and reduced the binding of C5a-F to monocytes. The expression of C5aR on low-density bone marrow cells was analyzed by setting appropriate gates during flow cytometry. Cells that bound C5a-F were found in all populations that contained granulocyte and monocyte precursors, but not in lymphocyte precursor populations. All C5aR+ bone marrow cells were CD34 and expressed high levels of CR3, which suggests a late appearance of C5aR during myeloid cell maturation. Our results indicate that C5aR is exclusively expressed on myeloid cells within the hematopoetic cell population.

Antibodies, Monoclonal↗

PubMed1999

The chemokine receptor CXCR4 is required for the retention of B lineage and granulocytic precursors within the bone marrow microenvironment.

We report that the chemokine receptor CXCR4 is required for the retention of B lineage and granulocytic precursors within fetal liver and bone marrow microenvironment. In CXCR4-deficient embryos, pro-B cells are present in blood but hardly detectable in liver; myeloid cells are elevated in blood and reduced in liver compared to wild-type embryos. Mice reconstituted with CXCR4-deficient fetal liver cells have reduced donor-derived mature B lymphocytes in blood and lymphoid organs. The numbers of pro-B and pre-B cells are reduced in bone marrow and abnormally high in blood. Granulocytic cells are reduced in bone marrow but elevated and less mature in the blood. B lineage and granulocytic precursors are released into the periphery in absence of CXCR4.

Animals↗

PubMed2003

Evaluation of the haemopoietic reservoir in de novo haemolytic paroxysmal nocturnal haemoglobinuria.

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired clonal disorder of the haemopoietic stem cell (HSC). The pathogenetic link with bone marrow failure is well recognized; however, the process of clonal expansion of the glycosylphosphatidylinositol (GPI)-deficient cells over normal haemopoiesis remains unclear. We have carried out detailed analysis of the stem cell population in 10 patients with de novo haemolytic PNH using the long-term culture-initiating cells (LTC-IC) assay in parallel with measurements of CD34+ cells and mature haemopoietic progenitors, granulocyte-macrophage colony-forming unit (CFU-GM) and CFU-erythroid [burst-forming units erythroid (BFU-E) + CFU granulocyte/erythroid/macrophage/megakaryocyte (GEMM)]. All patients had hypercellular bone marrows with erythroid hyperplasia, normal blood counts or mild peripheral blood cytopenias, increased reticulocyte counts and evidence of deficient GPI-anchored proteins. We found a significant reduction in the LTC-IC frequency in the CD34+ compartment of PNH patients (mean 2, range 1.3-3.0; n=6) compared with normal donors (mean 13, range 5.2-45.5; n=21) (P<0.0001). Furthermore, there was a significant reduction in the erythroid compartment [CFU-E/105 bone marrow mononuclear cells (BMMC) and CFU-E/105 CD34+ cells] of PNH patients, but no significant difference in the granulocyte-monocyte precursors (CFU-GM/105 BMMC or CFU-GM/105 CD34+ cells) compared with normal donors, suggesting that there is a defect in the early stem cell pool in PNH patients without clinical or haematological evidence of bone marrow failure.

Adult↗

PubMed1983

Steroid modulation of naturally occurring diurnal variation in circulating pluripotential haematopoietic cells (CFU-GEMM).

The number of committed granulocyte-monocyte precursors (CFU-GM) in circulation has been shown to increase following steroid administration in humans. To see if steroids could be used to improve the collection of peripheral blood stem cells for haematopoietic reconstitution, their effect on circulating CFU-GEMM was investigated. Six healthy young adults, three men and three women, were given 60 mg of prednisone orally at 8 a.m. on day 1. Blood CFU-GEMM and committed precursors (CFU-GM and BFU-E) were cultured in methylcellulose. Samples were taken at 4 p.m. the day before and at 8 a.m. on the day of steroid administration, and at 4, 8, 24 and, in a few cases, 48 h after steroid. Pre-treatment CFU-GEMM levels (per unit volume of blood) at 4 p.m. was 180 +/- 23% (mean +/- SEM) of that at 8 a.m., showing a significant (P less than 0.025) diurnal variation. 8 h after steroids there was a fall in CFU-GEMM to 28 +/- 4.5% of the 8 a.m. presteroid level. 24 h following steroid administration, CFU-GEMM rose significantly (P less than 0.05) to 188 +/- 33% of 8 a.m. baseline values; CFU-GM and BFU-E changes generally paralleled those noted for CFU-GEMM. These results suggest that blood levels of CFU-GEMM exhibit a significant diurnal variation. Oral prednisone given 24 h in advance of collection increases the 8 a.m. value to that found at 4 p.m. The steroid effect may be due to a resetting of the diurnal control mechanism. Use of this information may be important in collection of circulating haematopoietic stem cells for use in bone marrow reconstitution in man.

Adult↗

PubMed2005

To the intranucleolar translocation of AgNORs in leukemic early granulocytic and plasmacytic precursors.

Early leukemic granulocytic and plasmacytic precursors were studied in vitro and in vivo to provide an information on the intranucleolar distribution of AgNORs (silver stained nucleolus organizer regions). In most of these cells AgNORs appeared as clusters of silver stained particles distributed in the whole nucleolar body. On the other hand, in some leukemic early granulocytic precursors, i.e., in myeloblasts and promyelocytes enlarged AgNORs were translocated in the nucleolar peripheral part. In addition, the number of translocated AgNORs at the nucleolar periphery was significantly smaller. Such translocation of a reduced number of AgNORs was easily produced by experimental aging, i.e., starving of cultured leukemic early granulocytic precursors (HL-60 and K562 cells) in vitro and seems to be reversible. Similar translocation of a reduced number of AgNORs was also produced by aging of leukemic plasmacytic precursors. Thus, the translocation of the reduced number of AgNORs to the nucleolar periphery in some blastic leukemic hematopoietic cells might be an useful marker of their aging at the single cell level. However, more studies in this direction are required in the future.

Bone Marrow Cells↗

PubMed2006

Granulocyte colony-stimulating factor mobilizes more dendritic cell subsets than granulocyte-macrophage colony-stimulating factor with no polarization of dendritic cell subsets in normal donors.

Dendritic cells (DCs) are effective antigen-presenting cells. We hypothesized that increasing the DC populations in donor lymphocyte infusions (DLIs) may augment the graft versus malignancy effect, particularly if granulocyte-macrophage colony-stimulating factor (GM-CSF) mobilization resulted in increased precursor dendritic cell (pDC) 1 cells. Mature DCs, pDC1 cells, pDC2 cells, and CD34(+) cells from the same donor were compared after granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cell collections and GM-CSF mobilized DLI collections. Mobilization with G-CSF resulted in up to a 10-fold larger number of CD34(+) cells per kg and a 3-5-fold larger number of mature DCs, pDC1 cells, and pDC2 cells within the same donor compared with GM-CSF. The ratio of pDC1 to pDC2 in each donor remained constant with either cytokine. In this small sample of normal donors, it appears that G-CSF mobilizes more CD34(+) cells, mature DCs, pDC1 cells, and pDC2 cells within the same donor than does GM-CSF, with no significant polarization by G-CSF or GM-CSF for either pDC1 or pDC2 cells.

Adult↗

PubMed2003

The early progenitors of mouse dendritic cells and plasmacytoid predendritic cells are within the bone marrow hemopoietic precursors expressing Flt3.

Flt3 ligand (Flt3L) is a growth factor for hemopoietic progenitors and can promote the expansion of both conventional dendritic cells (DCs) and plasmacytoid predendritic cells (p-preDCs). The cells responding to Flt3L treatment and the precursors for the DCs and p-preDCs had not been fully characterized. We examined different mouse bone marrow (BM) hemopoietic precursor populations for the surface expression of Flt3 and tested them for early DC and p-preDC precursor activity. Most DC precursor activity, other than that given by multipotent hemopoietic stem cells, was within the downstream precursors expressing Flt3. The majority of mouse BM common lymphoid precursors expressed high levels of Flt3 and these were the most efficient precursors of both DCs and p-preDCs. In contrast, only a small proportion of the common myeloid precursors (CMPs) expressed Flt3, but the precursor activity for both DCs and p-preDCs was within this minor Flt3+ CMP fraction. The granulocyte and macrophage precursors and pro-B cells did not express Flt3 and had no DC or p-preDC precursor activity. These findings demonstrate that the early precursors for all DC subtypes are within the BM Flt3+ precursor populations, regardless of their lymphoid or myeloid lineage orientation.

Animals↗

PubMed1999

MR findings in ovarian granulocytic sarcoma.

Granulocytic sarcoma (chloroma) is a mass of malignant myeloid precursor cells in an extramedullary location. The female genital tract, including the ovary, may be the first site for clinical manifestation of granulocytic sarcoma. The MR findings are reported in a case of ovarian granulocytic sarcoma which preceded acute myelogenous leukaemia. Granulocytic sarcoma shows a mixed cystic and solid adnexal mass with intermediate signal intensity on T1 weighted images and hypointensity on T2 weighted images.

Child↗

PubMed1983

Transition from granulocyte to macrophage predominance in bone marrow cultures.

These studies examine the mechanisms underlying the transition from granulocytes to macrophages that characterizes cultures of bone marrow cells. Normal mouse marrow was cultured for several weeks in diffusion chambers (DCs) implanted in previously irradiated host mice. Previous studies with this system have shown that there is a period of logarithmic cell growth for 7 d following by a plateau in both total cell number and the numbers of CFU-S and CFU-C. The present studies show that this plateau in cell growth is associated with high cycling rates of both CFU-S and CFU-C. The plateau phase ends with a rapid decrease in the numbers of these progenitor cells. This is associated with a decline in the number of granulocytes, whereas macrophages persist at approximately the plateau level for the entire 48 d of culture. Transplantation of plateau phase cells into secondary DC cultures leads to a more rapid decline in the numbers of CFU-S and CFU-C followed by the total disappearance of granulocytes; in contrast, macrophage number undergoes a small increase which is maintained thereafter. When regular injections of 3H-thymidine are given to host mice bearing late phase secondary cultures, macrophage labelling rises to a plateau of only 30-40%, indicating that most macrophages at this stage of culture are long-lived cells. The kinetics of the stem cell changes implicate the CFU-C as the immediate precursor of granulocyte development in DC cultures but suggest that the CFU-S is the major determinant of overall cell renewal in this system. Macrophages doubtless also originate from CFU-C but, unlike granulocytes, these are often long-lived cells probably with some capacity for continuing cell division. These properties account for the often observed propensity of macrophages to repopulate bone marrow cultures from which stem cells and granulocytes have been depleted.

Animals↗

PubMed1989

Monoclonal antibody directed to human T-cell malignancy antigen.

A murine monoclonal antibody (B2D) against a cultured pre-T acute lymphoblastic leukemia (ALL) cell line THP-6 has been produced. The antibody reacted with seven out of eight cultured T-ALL cell lines and with leukemic cells from three out of four T-ALL/lymphoma patients. The antibody did not react with normal T and B lymphocytes, monocytes, granulocytes, platelets, erythrocytes, bone marrow lymphoid-like precursor cells, thymocytes and other acute and chronic leukemic cells of non-T cell origin. Furthermore, B2D did not react with phytohemagglutinin-activated T cells nor with concanavalin A-activated T cells. The molecules immunoprecipitated with B2D had molecular weights of 50-55 kD. Thus, B2D seems to be highly specific for T-cell malignancies. These results show that B2D defines one of human leukemia antigens which are expressed on the cell surface of T-ALL cells. Monoclonal antibody B2D may be useful for the subclassification of T-ALL cells and has therapeutic potential for a certain type of T-ALL.

Antibodies, Monoclonal↗

PubMed1992

Mobilization of peripheral blood progenitor cells by sequential administration of interleukin-3 and granulocyte-macrophage colony-stimulating factor following polychemotherapy with etoposide, ifosfamide, and cisplatin.

We report on the requirements that have to be met to combine a standard-dose chemotherapy regimen with broad antitumor activity with the mobilization of peripheral blood hematopoietic progenitor cells. Thirty-two cancer patients were given a 1-day course of chemotherapy consisting of etoposide (VP16), ifosfamide, and cisplatin (VIP; n = 46 cycles), followed by the combined sequential administration of recombinant human interleukin-3 (rhIL-3) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). Control patients received GM-CSF alone or were treated without cytokines. Maximum numbers of peripheral blood progenitor cells (PBPC) were recruited on day 13 to 17 after chemotherapy, with a median of 418 CD34+ cells/microL blood (range, 106 to 1,841) in IL-3/GM-CSF-treated patients, 426 CD34+/microL (range, 191 to 1,380) in GM-CSF-treated patients, and 46 CD34+/microL (range, 15 to 148) in patients treated without cytokines. In parallel, there was an increase in myeloid (10,490 colony-forming unit-granulocyte-macrophage [CFU-GM]/mL blood; range, 1,000 to 23,400), as well as erythroid (10,660 burst-forming unit-erythroid [BFU-E]/mL blood; range, 3,870 to 24,300) and multipotential (840 CFU-granulocyte, erythrocyte, monocyte, megakaryocyte [GEMM]/mL blood; range, 160 to 2,070) progenitor cells in IL-3 plus GM-CSF-treated patients. In GM-CSF-treated patients, significantly less precursor cells of all lineages were mobilized, particularly multipotential progenitors (400 CFU-GEMM/mL blood; range, 200 to 2,150). Only small numbers of CD34+ cells and clonogenic progenitor cells could be recruited in intensively pretreated patients. Our data document that after standard-dose chemotherapy-induced bone marrow hypoplasia, IL-3 plus GM-CSF can be used to recruit PBPC, which might shorten the hematopoietic recovery after high-dose chemotherapy in chemosensitive lymphomas or solid tumors.

Adult↗

PubMed1995

Effects of human FLT3 ligand on myeloid leukemia cell growth: heterogeneity in response and synergy with other hematopoietic growth factors.

A novel hematopoietic growth factor for primitive hematopoietic progenitor cells, the ligand for the flt3/flk2 receptor, (FL), has been recently purified and its gene has been cloned. In the present study, we investigated the effects of FL on the proliferation and differentiation of normal and leukemic myeloid progenitor cells. We demonstrate that FL is a potent stimulator of the in vitro growth of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), or G-CSF-dependent granulocyte-macrophage committed precursors from Lin- CD34+ bone marrow cells of normal donors. By contrast, FL does not affect the growth of erythroid-committed progenitors even in the presence of erythropoietin. The effect of FL on the proliferation and on the in vitro growth of clonogenic leukemic precursor cells was studied in 54 acute myeloid leukemia (AML) cases. Fresh leukemia blasts from 36 of 45 patients with AML significantly responded to FL without any relation to the French-American-British (FAB) subtype. FL stimulated the proliferation of leukemic blasts in a dose-dependent fashion. Synergistic activities were seen when FL was combined with G-CSF, GM-CSF, IL-3, or stem cell factor (SCF). FL as a single factor induced or increased significantly colony formation by clonogenic precursor cells from 21 of 24 patients with AML. In the presence of suboptimal and optimal concentrations of G-CSF, GM-CSF, IL3, SCF, or a combination of all factors, FL strongly enhanced the number of leukemic colonies (up to 18-fold). We also evaluated the induction of tyrosine phosphorylated protein on FL stimulation in fresh AML cells. We demonstrate that, on FL stimulation, a band of phosphorylated protein(s) of about 90 kD can be detected in FL-responsive, but not in FL-unresponsive cases. This study suggests that FL may be an important factor for the growth of myeloid leukemia cells, either as a direct stimulus or as a synergistic factor with other cytokines.

Cell Division↗