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.

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.

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.

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.

Increased serum level of interleukin-5 in a patient with episodic angioedema and eosinophilia syndrome

A case of episodic angioedema and eosinophilia syndrome is reported. An 18-year-old male suffered from monthly episodes of angioedema, pruritic papules, weight gain, and fever for twelve years. During the episodes, peripheral eosinophils and serum levels of interleukin (IL)-5, an eosinophil proliferating cytokine were elevated. Extensive evaluations disclosed neither visceral involvement nor evidence of parasitic infections, collagen diseases, or neoplastic disorders. Corticosteroid treatment brought about a dramatic clinical improvement concomitant with decrement of eosinophils and serum IL-5 was observed. These observations suggest that IL-5 may be a causative factor for this pathological state.

[Biochemistry and biological activities of eosinophil granule proteins]

The biochemistry, the molecular biology and the biological activity of the eosinophil granule proteins, major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN) and eosinophil peroxidase (EPO) are reviewed. MBP is present in the core of the eosinophil granule and is toxic to parasite and host cells. ECP and EDN are proteins in the matrix of the granule and share sequence similarity and ribonuclease activity. These two proteins can provoke the Gordon phenomenon in rabbits and are toxic to parasites. EPO consists of two polypeptide and is a toxin for parasite and host cells with or without H2O2. The common characteristics of these proteins are their high isoelectric points and cytotoxic activities.

GM-CSF and eosinophil chemotactic factors in an acute lymphoblastic leukemia patient with eosinophilia

We describe a patient with common acute lymphoblastic leukemia associated with blood and cerebrospinal fluid (CSF) eosinophilia. Serum obtained at onset and conditioned medium prepared from T cells obtained at remission stimulated with interleukin-2 contained eosinophil colony stimulating activity (Eo-CSA), which was confirmed to be predominantly GM-CSF. Leukemic cell conditioned medium and serum obtained at remission contained no Eo-CSA. The CSF contained increased eosinophil chemotactic activity, however, this factor was not identified.

[A case of new type scrub typhus (tsutsugamushi disease) presenting with acute respiratory failure and hemophagocytic syndrome]

A 47-year-old male was referred to our hospital with persistent high fever. He had received antibiotics (ASPC) for the diagnosis of acute infectious disease, which failed to respond, and subsequently developed marked lymphocytopenia and thrombocytopenia. During his hospitalization, hypoxic respiratory failure rapidly developed. A bone marrow aspiration revealed marked hemophagocytosis, leading to the tentative diagnosis of opportunistic respiratory infection associated with malignant histiocytosis. Treatment for suspected malignancy and Pneumocystis carinii pneumonia was commenced. However, because of the initial lack of response to ASPC, generalized skin rashes without an ordinary stick wound which had diminished before the hospitalization, and a history of working outdoors in a nearby mountain area, the possibility of new type tsutsugamushi disease was strongly suggested. Intravenous administration of minocycline promptly improved his symptoms and laboratory data. The diagnosis was confirmed by a significant increase in the titer of antibody to Rickettsia tsutsugamushi. The thrombocytopenia was considered to have been caused by co-existent hemophagocytic syndrome.

Myeloid progenitor cell growth characteristics and effect of G-CSF in a patient with congenital cyclic neutropenia

A 17-year-old male with congenital cyclic neutropenia was treated with recombinant human granulocyte colony stimulating factor (G-CSF) administered subcutaneously at 1 to 2 micrograms/kg per day. The peak and nadir counts of neutrophils and the peak counts of monocytes were significantly elevated, and the period of cycling decreased from 3 to 2 weeks. Bone marrow culture studies revealed the following abnormalities in granulocytic progenitor cells (CFU-G): a decrease in the concentrations of G-cluster forming cells, stimulated by a maximal dose of G-CSF, and a tendency of abnormally low responsive growth of the CFU-G to lower concentrations of G-CSF and GM-CSF. Our findings suggest that administration of G-CSF at relatively low doses overcomes or compensates for these abnormalities, though not completely, as fluctuation in the neutrophil counts persisted.

Interleukin-2 treatment-associated eosinophilia is mediated by interleukin-5 production

During a trial using recombinant human interleukin-2 (rhIL-2) immunotherapy for acute myeloblastic leukaemia (AML) in remission, eosinophilia was observed in all patients. We used in-vitro clonogenic assays to investigate the mechanism of the eosinophilia in five patients. The mean eosinophil count increased from 0.05 x 10(9)/l before rhIL-2 to 0.98 x 10(9)/l within 48 h of stopping the infusion, and an exponential correlation between the pretreatment lymphocyte CD4:CD8 ratio and the maximum eosinophil count was observed. RhIL-2 did not stimulate eosinophil colony formation by normal bone marrow. However, serum collected from patients during rhIL-2 infusion was a potent stimulator of eosinophil colony forming units (CFU-Eo), but had no significant stimulatory effect on granulocyte-macrophage colony forming units (CFU-GM). The CFU-Eo stimulation by pre-treatment serum was 2.8-fold higher than control serum. Serum collected during treatment stimulated CFU-Eo 12 times more than control serum (P less than 0.05). By pre-incubating patient serum, collected during rhIL-2 treatment, with monoclonal antibodies to murine IL-5, or human granulocyte-macrophage colony stimulating factor (GM-CSF), a reduction of 80% and 38% respectively in eosinophil and GM colony production was found. The CFU-Eo stimulating effect of patient serum was in the range of the CFU-Eo stimulating effect of normal serum, after the addition of 5 u/ml of recombinant murine IL-5. The results suggest that eosinophilia was caused by IL-5 and GM-CSF production by rhIL-2 stimulated CD4 positive lymphocytes. The location on chromosomes 5 of the genes for IL-5, GM-CSF and IL-3 may be associated with regulation of expression, by a common mechanism, of all the factors known to be involved in eosinophil production. This mechanism may be activated by IL-2 stimulation. The separate location on chromosome 17 of the G-CSF gene may explain the ability of IL-2 to produce a distinct stimulus to eosinophil but not neutrophil production.

Interaction of monocytes and T cells in the regulation of normal human megakaryocytopoiesis in vitro: role of IL-1 and IL-2

Autologous or allogeneic peripheral blood T cells can stimulate the human megakaryocyte progenitor cell (CFU-Meg)-derived colony formation in a dose-dependent fashion in agar cultures of nonadherent (NA), T cell-depleted (NT) bone marrow (BM) cells. Low concentrations of monocytes and T cells can collaborate in the stimulation of CFU-Meg colony formation or in the production of megakaryocyte colony stimulating factor (Meg-CSF) by T cells in the presence of mitogens or IL-2. Monocytes alone can produce only negligible Meg-CSF under any conditions. When monocyte conditioned medium (CM) was added to T cell-stimulated NA, NT BM cell cultures, CFU-Meg colony growth was appreciably increased compared with that stimulated by T cells alone. Dose-dependent increase in CFU-Meg colony growth was noted when varying concentrations of IL-1 were added to T cell-stimulated NA, NT cell cultures, although IL-1 itself could support no CFU-Meg colony growth in the absence of T cells. These data suggest that a synergistic interaction between T cells and monocytes during the production of Meg-CSF by T cells could be partly mediated by IL-1. IL-2 was found to stimulate Meg-CSF production by T cells in the presence or absence of mitogens. IL-2-stimulated Meg-CSF production by T cells was augmented by the addition of monocytes. Although IL-2 itself had no stimulatory effect on CFU-Meg colony growth, dramatic augmentation in the CFU-Meg colony number was noted when IL-2 was added to T cell-stimulated NA, NT cell cultures. High concentrations of monocytes and prostaglandin E (PGE) inhibited the CFU-Meg colony formation. These results suggest that IL-1 and IL-2 may play a stimulatory role on the normal human in vitro megakaryocytopoiesis, and may be involved in the development of reactive thrombocytosis and bone marrow megakaryocytic hyperplasia in various inflammatory diseases.

Interleukin 5 activity in sera from patients with eosinophilia

Sera from 10 patients with eosinophilia contained eosinophil colony stimulating factor (Eo-CSF) activity. Using anti murine (m) interleukin-5 (IL-5) antibody, we demonstrated that this activity was mainly derived from IL-5. Administration of prednisolone to patients decreased both Eo-CSF activity in sera and the number of eosinophils in blood. These results extend our recent study demonstrating that T cells from eosinophilic patients produce IL-5 with IL-2 stimulation and may support the speculation that IL-5 is an important factor which induces eosinophilia.

[Amylase-producing extramedullary plasmacytoma with multiple cutaneous metastasis following a solitary plasmacytoma of bone]

A 65-year-old woman was admitted because of multiple cutaneous tumors in the left lumbar area in March 1983. In 1979, she had been diagnosed as solitary plasmacytoma (IgG, kappa) of the left femur and amputation of the left leg had been performed. In 1981, the tumor relapsed in the left ilium in association with an increased level of serum IgG with M-component and normal activity of serum amylase. The serum M-protein had been disappeared after resection of the tumor. On admission laboratory examinations showed a slightly high level of serum IgG and elevated activities of serum and urine amylase. Amylase isoenzyme analysis revealed a predominance of the S-isozyme. Bone marrow aspiration revealed no atypical plasma cells. The supernate of cultured plasma cells obtained from the cutaneous tumor contained high amylase activity consisting exclusively of S-type. Thereafter serum amylase activities changed approximately in parallel with serum M-protein levels and total tumor volumes after chemotherapy or radiotherapy. At the terminal phase in 1986, however, serum amylase activities became extraordinarily high compared with serum M-protein levels, suggesting a clonal change of the plasmacytoma cells.

[CD8+ agranular lymphocyte proliferative disorder with T-cell receptor beta-chain gene rearrangement associated with thymoma and neutropenia]

A 58-year-old male with a 10-years history of thymoma was admitted to our hospital because of the respiratory infection. Hepatosplenomegaly and systemic lymphadenopathy were revealed on physical examination. Chest roentgenogram showed a large anterior mediastinal tumor and a right pleural effusion. Blood examination showed Hb 11.5 g/dl, leucocyte count 1,600/microliters (1% neutrophils, 34% monocytes, 65% lymphocytes) and platelet count 11.2 x 10(4)/microliters. The lymphocytes in the peripheral blood and pleural fluid were mostly small agranular mature lymphocytes and CD2+ 3+ 4- 8+. A monoclonal rearrangement of TCR beta chain gene was found using Southern blot analysis of the lymphocytes in the peripheral blood and pleural fluid. The CFU-GM colony formation by bone marrow cells was normal, and not suppressed by the patient's serum or peripheral blood lymphocytes. Neutrophil-associated IgG was increased with a direct immunofluorescence test. Serum IgG level was slightly decreased. Radiation therapy for thymoma exerted no effect. Treatment with prednisolone 60 mg daily resulted in complete disappearance of the pleural effusion and partial improvement of hepatosplenomegaly, thymoma and neutropenia. Histological examination of the thymoma revealed predominantly spindle cell type. He is still in good condition 21 months after diagnosis. This case seems to represent neoplastic proliferation of mature CD8+ T cells associated with thymoma.

[Spontaneous differentiation from myeloperoxidase-negative acute nonlymphocytic leukemia to acute myelomonocytic leukemia]

We reported a 68-year-old woman with acute nonlymphocytic leukemia, in whom the leukemia transformed from poorly differentiated myeloperoxidase (MPO)-negative type into myelomonocytic type during the observation without chemotherapy. Hematological findings on admission revealed a leukocyte count of 3,500/microliters with 48% blasts and a platelet count of 9.2 x 10(4)/microliters. Bone marrow aspiration showed 68.2% infiltration of blasts negative for MPO. Sudan black B and esterase stains. By electron microscopy MPO was detected in the endoplasmic reticulum and nucleoenvelope of the blasts. Large vacuole-like granules were MPO-negative. She was observed without administration of any antileukemic agent or an immunopotentiator. The leukocyte count rose gradually, in association with increases in the relative and absolute counts of mature neutrophils and monocytic cells, and the platelet count. Twenty-six months after the initial diagnosis, a blood examination showed a leukocyte count of 74,300/microliters with 20.5% mature neutrophils and 15.5% monocytic and a platelet count of 31.4 x 10(4)/microliters. Cytological, cytochemical, ultrastructural and immunological studies of the bone marrow cells showed features compatible with acute myelomonocytic leukemia (FAB M4). This case is unusual in respect that poorly differentiated ANLL transformed spontaneously into moderately differentiated ANLL.

[Neutrophil-associated IgG and neutrophil-binding IgG in autoimmune neutropenia]

Neutrophil-associated IgG (NAIgG) and neutrophil-binding IgG in sara (NBIgG) of 77 patients with neutropenia suspected to be caused by autoimmune mechanisms (group A) and 31 patients with aplastic anemia or myelodysplastic syndrome (group B) were assayed by flow cytometry. Auto-NBIgG was elevated in 32% of the patients in group A, particularly in about 70% of those with collagen diseases or ITP, but the level was normal in group B. Elevated NAIgG with normal auto-NBIgG levels was found in 27% of the patients in group A and in 64% of the patients in group B. The assay of auto-NBIgG was useful for detection of anti-neutrophil autoantibodies and for the diagnosis of autoimmune neutropenia. In addition, the level of NAIgG may be non-specifically elevated in non-immune neutropenia.

T cells from eosinophilic patients produce interleukin-5 with interleukin-2 stimulation

Anti-murine (m) interleukin-5 (IL-5) antibody was found to inhibit eosinophil (Eo) colony formation stimulated by recombinant human (rh) IL-5, but did not inhibit the production of Eo stimulated by rh IL-3 or granulocyte-macrophage colony-stimulating factor (GM-CSF). Conditioned medium (CM) prepared from eosinophilic patients' T cells with interleukin-2 (IL-2) stimulation (T-IL-2-CM), was found to contain CFU-Eo growth-stimulating factor. Using anti-mIL-5 antibody, we demonstrated that T-IL-2-CM from patients with eosinophilia contained a significant amount of IL-5. We also detected IL-5 mRNA in T cells from eosinophilic patients with IL-2 stimulation. These results suggest that IL-5 plays an important role in the induction of selective eosinophilia in humans and that IL-5 is produced from T cells with IL-2 stimulation.

Effect of human recombinant interleukin 4 on in vitro granulopoiesis of human bone marrow cells

Utilizing in vitro colony assay, we investigated the effect of human recombinant interleukin 4 (hIL-4) on granulopoiesis of normal human bone marrow cells. Though hIL-4 itself did not possess any colony-stimulating activity, the number of neutrophil (N) colonies, particularly the number of small colonies, supported by human recombinant G-CSF (hG-CSF) was significantly increased when hIL-4 was used as a costimulant. In contrast, the number of eosinophil (Eo) colonies supported by hIL-5 was decreased when hIL-4 was used as a costimulant. Also, the numbers of N and Eo colonies supported by hIL-3 or hGM-CSF were both significantly decreased when hIL-4 was added. These data suggest that hIL-4 has diverse positive and negative regulatory effects on human neutro- and eosinophilopoiesis as a cofactor of various CSFs.

Interleukin 2 stimulates the T-cells from patients with eosinophilia to produce CFU-Eo growth stimulating factor

To explore the mechanism of eosinophilopoiesis in patients with reactive eosinophilia, we studied the effect of interleukin 2 (IL-2) on the production of CSFs, especially CFU-eosinophil growth stimulating factor (CFU-Eo GSF) from T-lymphocytes in patients with reactive eosinophilia. Conditioned media (CM) prepared from patients' E rosette forming cells (ERFC) with or without IL-2 was assayed for CFU-Eo, CFU-monocyte, macrophage (CFU-M) and CFU-neutrophil (CFU-N) GSF. The addition of IL-2 to the ERFC significantly stimulated the production of CFU-Eo and CFU-M GSF while only CFU-M GSF increased in normals. Serial testing of the CFU-Eo GSF in ERFC-CM demonstrated that the ability of ERFC to produce CFU-Eo GSF with IL-2 stimulation was retained even when the eosinophilia had disappeared. These results suggest that CFU-Eo GSF is produced from T-cells with IL-2 stimulation and that the T-cells from patients produce IL-2 stimulation and that the T-cells from patients produce CFU-Eo GSF with IL-2 stimulation after the disappearance of eosinophilia.

Heterogeneity of in vitro growth pattern of megakaryocyte progenitors (CFU-M) in myeloproliferative disorders

In groups of 26 patients with myeloproliferative disorders (MPD), 8 with chronic myelogenous leukaemia (CML); 8 with polycythaemia vera (PV); 10 with essential thrombocythaemia (ET); and 6 patients with reactive thrombocytosis (RT), we studied the growth characteristics of bone marrow CFU-M in agar culture. The bone marrows from all the patients with MPD formed so called endogenous CFU-M colonies, in the absence of PHA-LCM, that increased in a dose-dependent manner with the addition of increasing concentrations of normal human AB-citrated plasma (NH-ABCP), while the bone marrows from all the patients with RT and from healthy controls formed few or no endogenous CFU-M colonies. In MPD, the endogenous CFU-M growth was enhanced by normal T cells in a dose-dependent fashion, and was decreased with the depletion of T cells from the marrow cells. These results suggest that the formation of endogenous CFU-M colonies is caused by hypersensitivity of CFU-M in MPD to NH-ABCP, which may contain a small amount of Meg-CSF, and/or by in vitro T cell stimulation. Among MPD, the endogenous CFU-M growth in ET was significantly lower than that of other MPD patients; however, the total number of ET CFU-M grown in the presence of PHA-LCM was the highest. These data show that the bone marrow CFU-M in MPD are heterogeneous with respect to in vitro growth pattern or sensitivity to exogenous Meg-CSF.

Effect of human recombinant interleukin 5 and G-CSF on eosinophil colony formation

Human recombinant (r) IL-5 was shown to have the activity to stimulate eosinophil (Eo) colony formation from human non-T, non-adherent bone marrow cells. The majority of these colonies were found to contain a small number of basophils, macrophages or neutrophils. Human rG-CSF, which alone did not stimulate Eo colony formation, showed an enhancing effect on Eo colony formation when added with IL-5. IL-5 seems to stimulate the proliferation and differentiation of CFU-Eo, while G-CSF acts on the early stage of eosinophilopoiesis.

Specific production of eosinophil colony stimulating factor from sensitized T cells from a patient with allergic eosinophilia

To explore the possibility that an eosinophil colony stimulating factor (EO-CSF) is elaborated independently of neutrophil CSF (N-CSF), we compared the effect on the production of EO-CSF and N-CSF of adding a specific antigen, an aspergillus extract, to peripheral blood leucocytes of an eosinophilic patient with allergic bronchopulmonary aspergillosis. Conditioned media prepared from the patient's mononuclear (MN) and T cells were assayed for EO-CSF and N-CSF activities by agar culture technique, using normal human nonphagocytic MN bone marrow cells as target cells. The addition of the specific antigen to the cultures of the patient's MN or T cells significantly stimulated the production of EO-CSF, but not that of N-CSF, while the patient's non-T cells and normal MN or T cells were not stimulated by the antigen challenge to produce either CSF. These results suggest that EO-CSF is a factor distinct from N-CSF, that its production is dependent on the presence of sensitized T cells with antigen-specific stimulation, and that it might be one of the causes of blood eosinophilia in this patient.