Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.

We studied the effects of polymorphonuclear neutrophils (PMN) and immature myeloid cells on the granulocyte colony-stimulating factor (G-CSF) level in vitro to better understand the regulatory mechanisms of neutropoiesis. Intact normal PMN decreased the G-CSF level after incubation with recombinant human (rh) G-CSF in a time- and dose-dependent manner. The percent reduction decreased as the concentration of rhG-CSF increased. However, the cell-free PMN-conditioned medium (PMN-CM) did not decrease the G-CSF level. The intact PMN also decreased the granulocyte-macrophage (GM)-CSF level after culture with rhGM-CSF, but did not affect the monocyte (M)-CSF level after culture with rhM-CSF. Normal bone marrow (BM) immature neutrophilic cells and G-CSF-dependent acute myeloid leukemic cells (OCI/AML la) also decreased the G-CSF level, whereas K-562 cells, which have no detectable G-CSF receptors, did not affect it. Phenylarsine oxide (PhAsO), an inhibitor of endocytosis of ligand receptor complex, abrogated this decreasing effect of intact PMN and OCI/AML la cells. These findings suggest that mature and immature myeloid cells negatively regulate neutropoiesis by, at least in part, decreasing the G-CSF level probably through receptor-mediated continual absorption and metabolism of G-CSF.

Identification of surface molecules on eosinophils and lymphocytes in blood from patients with eosinophilia.

Surface molecules on eosinophils and lymphocytes in blood from patients with hypereosinophilic syndrome (HES), Kimura's disease and normal volunteers were examined. In all 3 patients with HES, CD54-positive eosinophils were increased and in some patients with HES and Kimura's disease HLA-DR-positive eosinophils were increased. Additionally, CD11b-positive, CD16-positive, CD25-positive, CD54-positive, CD69-positive and HLA-DR-positive lymphocytes were increased in some of these patients.

Clonal involvement of eosinophils in therapy-related myelodysplastic syndrome with eosinophilia, translocation t(1;7) and lung cancer.

We report a therapy-related MDS (RAEB) patient with eosinophilia, unbalanced translocation der(7)t(1;7) (q12;q22) and lung cancer. We observed no increase in cytokine levels in serum or in the conditioned medium (CM) of peripheral T cells cultured with or without IL-2. When bone marrow (BM) cells were cultured with GM-CSF, IL-3 and SCF in a semisolid system, the colonies were exclusively eosinophilic. Cytogenetic analysis of the colony cells identified the same chromosome abnormality in all metaphases to that of BM cells. Suspension and clonogenic colony assay of BM cells cultured with various cytokines showed predominant eosinophilic growth and differentiation with GM-CSF, but not with the other cytokines examined. These findings, together with mild morphological abnormalities of eosinophils, indicate clonal involvement of eosinophils in the myelodysplastic syndrome (MDS) clone, and that the eosinophilia was derived from the neoplastic clone with the translocation and was not associated with the patient's lung cancer.

Preferential inhibitory effect of soluble factor(s) in human bone marrow stromal cells on proliferation of K562 leukemia cells versus normal myeloid progenitor cells.

We examined the effect of diffusible factors generated during the culture of the KM102 stromal cell line as well as in long-term bone marrow culture (LTBMC) on K562 leukemia cells, with respect to proliferation of clonogenic cells as well as total cells, and compared it with the effect on normal myeloid progenitors (CFU-GM). Proliferation of K562 cells plated in diffusion chambers was inhibited by coculture for 3-5 days in the fluid phase of stromal cell cultures or stromal cell-conditioned medium (CM), while CFU-GM proliferation was not inhibited under the same culture conditions. The inhibitory action was not attributed to the exhaustion of nutrients or growth promoting factors such as stem cell factor. These findings suggest that bone marrow stromal cells secrete diffusible molecule(s) which exert a preferential inhibitory effect on K562 leukemic cells vs. normal CFU-GM. Neutralization with antibodies against hematopoiesis-inhibiting cytokines such as TGF-beta 1, IFN-gamma, MIP-1 alpha and IL-4 which were detected in stromal cell-CM, failed to abrogate the inhibitory effect of KM102-CM on K562 cells. IL-1, TNF-alpha, IFN-alpha and lipopolysaccharides, known as stimulators of various cytokines from stromal cells, could not enhance the inhibitory activity. Further characterization of the factors may have implications for the treatment of leukemias.

Internal DNA deletion within the BCL-6 gene on untranslocated chromosome in non-Hodgkin's lymphoma with 3q27 abnormality.

Chromosomal translocations involving the band 3q27 are recognized as common specific cytogenetic abnormalities in B cell non-Hodgkin's lymphoma (NHL), and the BCL-6 gene, identified on 3q27 was shown to be disrupted by these translocations. Previously, we have reported biallelic BCL-6 rearrangements occurring in some patients with B cell NHL. In the present study, we describe a NHL patient with t(3;22)(q27;q11) translocation. In this patient, biallelic BCL-6 abnormalities were indicated by Southern blot analysis. Further studies revealed that one of the two independent abnormalities was a juxtaposition to the immunoglobulin (Ig) lambda gene associated with chromosomal translocation, whereas the other was an internal DNA deletion of 1.5 kb area on untranslocated chromosome 3. Deletion junctions were located within the first exon and the 5' region of the first intron. The result provides the evidence that, besides chromosomal translocation, submicroscopic local DNA recombination can cause structural alteration of the BCL-6 gene.

Eosinophilia associated with proliferation of CD(3+)4-(8-) alpha beta+ T cells with chromosome 16 anomalies.

We describe a patient with eosinophilia and an abnormal CD(3+)4-(8-) alpha beta+ T-cell population. Chromosomal analysis of sorted CD(3+)4-(8-) cells revealed abnormal karyotypes on chromosome 16. In the presence of IL-2 the production of IL-5 from CD(3+)4-(8-) cells was higher than that from CD(3+)4-(8-) cells. Eosinophil survival-enhancing activity in the patient serum was inhibited by a combination of anti-IL-5 and anti-GM-CSF monoclonal antibodies. These data suggest that increased production of IL-5 and GM-CSF from the abnormal CD(3+)4-(8-) cells might cause eosinophilia.

Eosinophils negatively regulate eosinophilopoiesis by decreasing IL-5 levels.

The effect of mature eosinophils on eosinophilopoiesis was studied. Mature eosinophils decreased the interleukin-5 (IL-5) level after incubation with IL-5 and suppressed IL-5 release from non-adherent mononuclear cells. These findings suggest that eosinophils negatively regulate eosinophilopoiesis by decreasing the IL-5 level.

[Eosinophil colony stimulating factor (Eo-CSF) activity and soluble interleukin-2 receptor (sIL-2R) in patients with reactive eosinophilia].

To explore the pathophysiology of patients with reactive eosinophilia from unknown cause, we measured the eosinophil colony stimulating factor (Eo-CSF) activity in the interleukin-2 (IL-2) stimulated lymphocyte conditioned medium (CM) prepared from 22 patients with reactive eosinophilia. Eo-CSF activity, the levels of interleukin-5 (IL-5) and granulocyte-macrophage colony stimulating factor (GM-CSF) were increased in the CM from patients with high IgE levels. Hydrocortisone decreased the level of Elo-CSF in the CM. Elevated serum levels of soluble IL-2 receptor (sIL-2R) were presented in 13 out of 15 patients with eosinophilia. The sIL-2R levels in patients with marked eosinophilia (>3000/mu l) were higher than those in patients with mild eosinophilia (< or = 3000/mu l). High sIL-2R levels were noted in T cell CM from 3 out of 15 patients and in eosinophil CM from 1 out of 4 patients. These data suggested that lymphocyte from eosinophilic patients with elevated IgE produce Eo-CSF, IL-5 and GM-CSF by IL-2 stimulation. Eo-CSF production is inhibited by hydrocortisone. SIL-2R is released from lymphocyte and in some case may be released from eosinophils.

Serum concentrations of IL-5, GM-CSF, and IL-3 and the production by lymphocytes in various eosinophilia.

The concentrations of interleukin-5 (IL-5), granulocyte-macrophage colony-stimulating factor GM-CSF, and interleukin-3 (IL-3) in serum and in IL-2-stimulated lymphocyte culture medium (L-IL2-CM) prepared from patients with reactive eosinophilia were measured by enzyme-linked immunosorbent assay (ELISA). Serum IL-5 levels were increased in 16 out of 42 cases. GM-CSF and IL-3 were below the detectable levels in all sera examined. The concentrations of IL-5 and GM-CSF in L-IL2-CM were increased in 10 out of 29 patients. IL-3 was below the detectable levels in all L-IL2-CM.

Biallelic DNA rearrangements and deletions within the BCL-6 gene in B-cell non-Hodgkin's lymphoma.

Chromosomal translocations involving band 3q27 are recently described common specific cytogenetic abnormalities in B-cell neoplasms, and the BCL-6 gene, identified on 3q27, was shown to be disrupted and over-expressed in lymphoma cells having these chromosomal translocations. In the present study we found rearrangements within the BCL-6 gene in seven out of 35 cases with B-cell non-Hodgkin's lymphoma (NHL). Further analysis revealed that three of these patients with BCL-6 abnormality had multiple rearranged bands hybridized with probes from a single restriction fragment within the major translocation cluster (MTC), suggesting that independent DNA rearrangements would occur on both alleles. Additionally, Southern blot analysis indicated that three patients carry deletions encompassing the area containing the first exon of the BCL-6 gene. Our results suggest that biallelic DNA rearrangements and deletions would occasionally occur in NHL patients with BCL-6 abnormality.

[Complete remission achieved by low-dose Ara-C, aclarubicin and rhG-CSF (CAG) therapy in acute non-lymphocytic leukemia with monosomy 7 occurring after severe aplastic anemia].

We report a case of acute myelogenous leukemia (AML), which developed from severe aplastic anemia (SAA) and was successfully treated by low-dose Ara-C and aclarubicin with concomitant use of G-CSF (CAG therapy). A 37-year-old male was admitted for scrutiny of pancytopenia and diagnosed as SAA because of hypocellular bone marrow without abnormal or dysplastic cells. Although hematopoiesis recovered with steroid pulse therapy followed by administration of anabolic steroids, 29 months after initial onset of SAA, he presented as AML (FAB-M6), as his bone marrow Contained 21.6% leukemic myeloblasts and 56% of erythroblasts. Chromosome study revealed 45, XY, -7 in 14 of 20 cells analyzed. Complete remission was achieved by administration of low-dose Ara-C (20 mg/m2 for 7 days) and aclarubicin (14 mg/m2 for 4 days) along with G-CSF (200 micrograms/m2 for 7 days), without any severe complications. In the previous reports in Japan since 1982, 7 out of 8 cases with AML developing from SAA died within a year. Our results indicate that CAG therapy is useful for treatment for this subset of AML with poor prognosis.

Serum concentrations of interleukin-5 and the production of lymphocytes in reactive eosinophilia.

The concentrations of interleukin-5 (IL-5) in serum and in IL-2-stimulated lymphocyte culture medium (L-IL2-CM) prepared from patients with reactive eosinophilia were measured by enzyme-linked immunosorbent assay. The serum IL-5 concentration was increased in 16 of 34 cases. The concentrations of IL-5 in L-IL2-CM were increased in 8 of 21 patients.

IL-5 mRNA expression in blood lymphocytes from patients with Kimura's disease and parasite infection.

Blood lymphocytes from patients with eosinophilia are known to produce interleukin-5 (IL-5) with appropriate stimulation in vitro. To determine whether blood lymphocytes from these patients produce IL-5 in vivo, we tested the IL-5 mRNA expression in blood lymphocytes immediately after separation by reverse-transcriptase polymerase chain reaction (RT-PCR) method. We found that lymphocytes from eosinophilic patients expressed IL-5 mRNA, but lymphocytes from normal volunteers did not express the lymphokine. These findings suggest that in patients with eosinophilia, peripheral blood lymphocytes produce IL-5 in vivo.

Serum levels of major basic protein in patients with or without eosinophilia: measurement by enzyme-linked immunosorbent assay.

A bone marrow proteoglycan (BMPG) has been purified which consists of the same amino acid sequence as that of pro-MBP, and produced two anti-BMPG mAbs. Serum levels of major basic protein (MBP), a cationic protein rich in the eosinophil granule, were measured in patients with eosinophilia or allergic diseases by an enzyme-linked immunosorbent assay (ELISA) using these mAbs. The serum levels of MBP in patients with eosinophilia (n = 64) and in those with allergic diseases without eosinophilia (n = 32) were elevated significantly (P < 0.001 and P = 0.038, respectively). There was a weak positive correlation between the serum levels of MBP and the eosinophil counts in the patients with eosinophilia (r = 0.38). Among these patients, extremely high serum levels of MBP were found in those with hypereosinophilic syndrome (HES) and Kimura's disease. Serum levels of MBP decreased more slowly than the eosinophil counts in patients with eosinophilia when treated by glucocorticoids. We conclude that measurement of serum levels of MBP is useful in evaluating the total-body proliferation and infiltration of eosinophils more accurately than following-up the eosinophil counts alone.

Regulation of interleukin-5 production by interleukin-4, interferon-alpha, transforming growth factor-beta and interleukin-6.

Normal lymphocytes produce IL-5 with PHA and PMA stimulation. In this system, IL-5 production was enhanced by IL-4 and was inhibited by IFN alpha, TGF beta and IL-6.

[Non-Hodgkin's T cell lymphoma associated with marked eosinophilia].

A case of non-Hodgkin's T cell lymphoma (diffuse lymphoma, large cell type) associated with marked eosinophilia and pleurisy in a 57-year-old male is reported. The leukocyte count was 12.5 x 10(3)/microliters and eosinophil count was 53% and the absolute count of 6.6 x 10(3)/microliters. The patient's serum and pleural effusion fluid, containing abundant lymphoma cells, showed eosinophil colony stimulating factor (Eo-CSF) activity. Conditioned medium (CM) prepared from patient's T cells (T-CM) produced Eo-CSF and this was enhanced by interleukin-2 (IL-2) stimulation. We demonstrated that the patient's serum contained a significant amount of interleukin-5 (IL-5) and the patient's T-CM, particularly after IL-2 stimulation contained a significant amount of granulocyte-macrophage colony-stimulating factor (GM-CSF). These findings suggest that Eo-CSF produced by neoplastic T cells or normal T cells activated by tumor antigen stimulated the production of eosinophils in this patient and that both IL-5 and GM-CSF might play a role in Eo-CSF activity.

Eosinophilia in myelodysplastic syndrome with a (12;21)(q23;q22) translocation.

Cytogenetic analysis of bone marrow (BM) cells from a patient with myelodysplastic syndrome (MDS) associated with eosinophilia showed a 45,XY,t(12;21)(q23;q22), -17 karyotype. We performed clonal and suspension cultures using the patient's BM mononuclear cells to clarify the mechanism of eosinophilia. Eosinophil colonies formed in the presence of interleukin-5 (IL-5) and granulocyte-macrophage colony-stimulating factor (GM-CSF), but not in the presence of IL-3. When BM cells were cultured in suspension in the presence of IL-5, they differentiated to mature eosinophils, and chromosome analysis identified the 45,XY,t(12;21)(q23;q22), -17 karyotype in all metaphases. The patient's serum did not stimulate eosinophil proliferation or differentiation in comparison with normal serum, however, these data suggest that the abnormal clone with 45,XY,t(12;21)(q23;q22), -17 karyotype may have an increased responsiveness to IL-5 and GM-CSF, resulting in eosinophilia.