Treatment of childhood-onset cyclic neutropenia with recombinant human granulocyte colony-stimulating factor.

Abstract: Two Spanish families with α thalassaemia, including 4 individuals with Hb H disease, are described. DNA mapping shows that, in addition to the common α thalassaemia determinant (-α^3.7), a different and previously unreported allele is present in each family. In one, there is a deletion of 10.5–12 kb of DNA including both α genes (^-SPAN). in the other, a deletion of more than 100 kb has removed the entire α globin gene complex (^-BR).     

Chemotactic activity of recombinant human granulocyte colony- stimulating factor

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) induced migration across polycarbonate filters of human polymorphonuclear leukocytes (PMN). rhG-CSF was active in inducing PMN migration at concentrations greater than or equal to 10 to 100 U/mL (7 to 70 ng/mL). rhG-CSF did not contain appreciable levels of endotoxin contamination as assessed by Limulus amebocyte assay, and Polymixin B did not affect the chemotactic activity of rhG-CSF. A monoclonal anti-G- CSF antibody blocked the induction of migration by G-CSF, thus establishing that the cytokine was responsible for the activity of the recombinant preparation. Checkerboard analysis was performed by seeding different concentrations of G-CSF above and/or below the filter and revealed that the migratory response to this cytokine was best observed in the presence of a positive concentration gradient between the lower and upper compartments of the chamber, thus indicating an actual chemotactic effect. When different migrating cells were examined, rhG- CSF was inactive on large granular lymphocytes and endothelial cells under conditions in which appropriate reference attractants were active. In contrast, rhG-CSF elicited a chemotactic response in monocytes inhibited by specific antibody. Thus, G-CSF is a chemotactic signal for phagocytes. This cytokine, when produced at inflammatory sites, may contribute to the recruitment of phagocytes from the blood compartment to amplify resistance against certain noxious agents.     

The effect of three human recombinant hematopoietic growth factors (granulocyte-macrophage colony-stimulating factor, granulocyte colony- stimulating factor, and interleukin-3) on phagocyte oxidative activity

Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF.     

Characterization of the clinical effects after the first dose of bacterially synthesized recombinant human granulocyte-macrophage colony- stimulating factor

Bacterially synthesized recombinant human granulocyte-macrophage colony- stimulating factor (rhGM-CSF) is an agent with therapeutic potential for neutropenic states, but even at doses below the maximal tolerated dose adverse effects occur during short courses of administration. We have recognized a syndrome of hypoxia and hypotension that follows the first but not subsequent doses of rhGM-CSF. Thirteen of 42 patients receiving rhGM-CSF in phase I studies and 4 of 6 patients in a phase II study developed a reaction that occurred after the first dose of 24 of 78 cycles of rhGM-CSF therapy. The reaction was characterized by flushing (16 of 24), tachycardia (16 of 24), hypotension (14 of 24), musculoskeletal pain (13 of 24), dyspnea (12 of 24), nausea and vomiting (11 of 24), rigors (5 of 24), involuntary leg spasms (3 of 24), and syncope (3 of 24). The reaction did not occur after any of more than 600 second and subsequent consecutive rhGM-CSF doses. Oxygen saturation decreased during first-dose reactions by 8% +/- 4% as compared with 3% +/- 1% on first days without reactions (P less than .001) and 2% +/- 1% on subsequent days (P less than .001). Pulmonary dysfunction was characterized by hypoxemia (59 +/- 9 mm Hg, mean +/- SD) that was fully correctable with supplementary oxygen, decreased single-breath carbon monoxide diffusion capacity, and increased alveolar-arterial oxygen gradients (25 +/- 6 to 60 +/- 4 mm Hg, mean +/- SD), but no significant abnormalities on chest roentgenogram or lung perfusion scan. Factors predisposing to reactions were rhGM-CSF dose greater than or equal to 3 micrograms/kg (P less than .01), intravenous (IV) rather than subcutaneous (SC) administration (P less than .05), occurrence of a reaction after the first dose of a previous cycle of rhGM-CSF therapy (P less than .01), and for patients receiving 15 micrograms/kg/d by SC bolus, the presence of lung cancer (P less than .05). Administration of 15 micrograms/kg/d rhGM-CSF by 24-hour SC infusion rather than SC bolus resulted in a delayed onset of reaction from 30 +/- 8 minutes to 240 +/- 190 minutes (mean +/- SD, P less than .001), and a slower rate of initial transient decrease in neutrophil levels and a more prolonged duration of transient leukopenia. The time of onset of reactions correlated with the rate of rise of rhGM-CSF levels.(ABSTRACT TRUNCATED AT 400 WORDS)     

Biosynthetic (recombinant) human granulocyte-macrophage colony- stimulating factor: effect on normal bone marrow and leukemia cell lines

To examine the biologic properties of the molecule encoded by the human gene for granulocyte-macrophage colony-stimulating factor (GM-CSF), we expressed the cloned complementary DNA (cDNA) in transfected monkey COS cells and purified the resultant protein. Purified biosynthetic human GM-CSF was added to cultures of normal hematopoietic progenitor cells in semisolid media, and the resulting colonies were characterized cytochemically. Non-adherent light-density bone marrow cells from healthy adult volunteers were maximally stimulated with GM-CSF (approximately 250 pmol/L, and four types of colonies were consistently identified by aspirating the individual colonies and staining with a triple stain for specific and nonspecific esterases and eosinophilic granules. Pure neutrophilic granulocyte (G), mixed granulocyte- macrophage (GM), pure macrophage (M), and pure eosinophil (EO) colonies were observed, the mean incidences on day 8 being 70%, 20%, 5%, and 5%, and on day 14, 7.5%, 16.6%, 50.9%, and 25.0%, respectively. In all types of colonies, complete maturation to segmented forms or typical macrophages was detected. GM-CSF did not enhance the growth of BFU-E from normal peripheral blood buffy coat cells in the simultaneous presence of erythropoietin alone or erythropoietin with purified erythroid-potentiating activity. GM-CSF stimulated HL-60 and KG-1 colony formation twofold and fivefold, respectively; consistent differentiation induction towards monocytic and eosinophilic lineages was observed in HL-60 but not in KG-1. These in vitro findings indicate that GM-CSF is a multilineage stimulator for progenitor cells of G, GM, M, and EO colonies.     

Induction of anti-recombinant human granulocyte-macrophage colony- stimulating factor (Escherichia coli-derived) antibodies and clinical effects in nonimmunocompromised patients

The pharmacokinetics of recombinant human granulocyte-macrophage colony- stimulating factor (rhGM-CSF), induction of anti-GM-CSF antibodies, and clinical effects related to the induction of the antibodies were analyzed in patients with metastatic colorectal carcinoma (CRC) who were not on chemotherapy (n = 20, nonimmunocompromised patients). rhGM- CSF (250 micrograms/m2/d; Escherichia coli-derived) was administered subcutaneously for 10 days every month for 4 months. Eight patients with multiple myeloma (MM) on intensive chemotherapy followed by rhGM- CSF treatment were also included (immunocompromised patients). After a single injection of GM-CSF at the first cycle in CRC patients, the maximum calculated concentration (Cmax) was 5.24 +/- 0.56 ng/mL; the half life (T1/2) was 2.91 +/- 0.8 hours; and the area under the concentration curve (AUC) was 30.86 +/- 6.03 hours x ng/mL (mean +/- SE). No anti-GM-CSF antibodies were detected. During the subsequent cycles, 95% of the CRC patients developed anti-GM-CSF IgG antibodies, which significantly altered the pharmacokinetics of rhGM-CSF at the third and fourth cycles with decreased Cmax (2.87 +/- 0.57 ng/mL; P < .05), T1/2 (1.57 +/- 0.2 hours; P < .05), and AUC (14.90 +/- 4.10 hours x ng/mL; P < .005). The presence of anti-GM-CSF antibodies significantly reduced the GM-CSF-induced enhancement of granulocytes, and there was a clear tendency for a decreased increment of monocytes. Antibodies diminished systemic side effects of rhGM-CSF. Only 1 of 8 MM patients showed a very low anti-GM-CSF antibody titer after GM-CSF therapy, as shown by enzyme-linked immunosorbent assay and Western blot. Therefore, in nonimmunocompromised patients, exogenous nonglycosylated GM-CSF induced an anti-GM-CSF IgG antibody response in practically all patients, which seemed to be of clinical significance. In immunocompromised patients, virtually no significant antibody response was shown.     

Successful treatment of autoimmune neutropenia with recombinant human granulocyte-colony stimulating factor (R-metHuG-CSF)

Autoimmune neutropenia (AIN) is characterized by antibody mediated peripheral destruction of neutrophils. Since there is no effective treatment, antibiotics have to be used frequently for recurrent infections. Five selected patients with serologically proven AIN were treated with r-metHuG-CSF at 5–8 μg/kg body weight (300–480 μg) daily; the dose and frequency of r-metHuG-CSF was reduced after neutrophil counts above 1.0×10⁹/l were obtained. R-metHuG-CSF is effective in AIN and causes a sustained rise in ANC which can be maintained on a low dose administered twice or thrice weekly.     

Expression and function of the human granulocyte-macrophage colony- stimulating factor receptor alpha subunit

To determine the expression and function of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha chain (GMR alpha) during hematopoiesis and on leukemic cells, monoclonal antibodies were raised by immunizing mice with cells expressing high levels of human GMR alpha. A pool of five antibodies isolated from three different mice was used to characterize GMR alpha. This antibody pool (anti-GMR alpha) immunoprecipitated a protein with the expected molecular weight of GMR alpha from COS cells transiently transfected with the GMR alpha gene. In factor-dependent cells, GMR alpha existed as a phosphoprotein. However, its phosphorylation was not stimulated by the presence of GM- CSF. Anti-GMR alpha inhibited the GM-CSF-dependent growth of cell lines and normal bone marrow cells and inhibited the binding of iodinated GM- CSF to its receptor. Cell surface expression of GMR alpha was examined using anti-GMR alpha and flow cytometry. GMR alpha was readily detectable on both blood monocytes and neutrophils. In adherence- depleted normal bone marrow, two separate populations expressed GMR alpha. The most positive cells were predominantly macrophages, whereas the cells that expressed less GMR alpha were largely myelocytes and metamyelocytes. A small population of lin-CD34+ or CD34+CD38- cells also expressed GMR alpha, but they were not capable of significant growth in colony-forming assays. In contrast, the majority of lin-CD34+ and CD34+CD38- cells were GMR alpha-, yet they produced large numbers of myeloid and erythroid colonies in the same assay. Malignant cells from patients with leukemia were also tested for GMR alpha expression. All of the myeloid leukemias and only rare lymphoid leukemias surveyed tested positive for GMR alpha. These results show that anti-GMR alpha is useful for the functional characterization of the GMR alpha and for the detection of myeloid leukemia and that GMR alpha is expressed on certain lineages throughout hematopoietic development; however, progenitors that express the receptor may have a reduced capacity to proliferate in response to hematopoietic growth factors.     

Therapeutic potential of recombinant granulocyte-macrophage colony- stimulating factor and interleukin-3 in murine B-cell leukemia

The antileukemic activity of murine recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) and a combination of rGM-CSF and recombinant interleukin-3 (rIL-3) was examined by using a murine model of spontaneous B-cell leukemia (BCL1) in BALB/c mice. All untreated mice inoculated with 2 x 10(2) BCL1 cells developed leukemia within 4 weeks, with extreme lymphocytosis and a massive increase in both spleen weight and cell number while the number of myeloid progenitors (CFU-C) per spleen was decreased. In contrast, rGM-CSF-or rGM-CSF- and rIL-3- treated recipients did not show any evidence of leukemia or splenomegaly at 4 weeks and showed a significant increase in CFU-C per spleen. Hematologic parameters in the peripheral blood of untreated mice showed anemia and thrombocytopenia. Significant elevations in these parameters were recorded in mice treated with either protocol of CSF. Treatment of recipient mice with either rGM-CSF or rGM-CSF and rIL- 3 prolonged their median survival from 6 weeks in untreated controls (range, 5 to 9 weeks) up to the time they were killed at 105 days. Adoptive transfer of spleen cells obtained from mice treated with rGM- CSF, mice treated with a combination of rGM-CSF and rIL-3, and untreated controls, into normal secondary recipients indicated improved survival in recipients inoculated with rGM-CSF. These data indicate that CSFs may inhibit in vivo expansion of leukemic cells of lymphoid origin.     

重组人粒细胞集落刺激因子治疗老年软组织肉瘤患者化疗后骨髓抑制的临床观察

目的观察比较两种方法应用重组人粒细胞集落刺激因子(rhG-CSF)治疗老年软组织肉瘤患者化疗引起白细胞下降的效果,为临床用药提供指导。方法选择解放军总医院骨科2010年1月至2014年1月经由我院病理科确诊的原发性软组织肉瘤老年患者82例,全部采用MAID(美司钠、多柔比星、异环磷酰胺及达卡巴嗪)化疗方案,随机分为两组,A组患者在全部化疗给药结束后24 h内应用rhG-CSF注射液2.5μg/kg,1次/d,连续应用14 d至白细胞≥4.0×10~9/L停药。B组患者于全部化疗给药结束后监测血常规,当达到Ⅱ级骨髓抑制时应用rhG-CSF注射液5μg/kg,1次/d,连续应用7 d或白细胞≥4.0×10~9/L停药。观察患者化疗后白细胞最低值、恢复到的最高值及恢复时间、用药时间及次数。结果 (1)两组患者在一般情况方面差异无统计学意义(P0.05)。(2)两组患者的白细胞最低值差异无统计学意义(P0.05),B组患者的白细胞最高值及恢复时间略低于A组(P0.05)。(3)B组患者在用药时间及用药次数方面明显低于A组患者(P0.05)。结论 B组患者采用的高剂量短时间给药方法可确切提高外周血白细胞数目,同时减轻患者所受痛苦,值得临床应用。     

Phase I/II study of recombinant human granulocyte-macrophage colony- stimulating factor in aplastic anemia and myelodysplastic syndrome

We performed a phase I/II study of the administration of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) to patients with aplastic anemia or myelodysplastic syndrome. Doses ranging from 15 to 480 micrograms/m2 were administered as a one-hour or four-hour intravenous infusion daily for 7 days or as a 12-hour infusion for 14 days. Temporary improvements were seen in granulocyte counts, monocyte counts, and reticulocyte counts in six of eight patients with aplastic anemia and five of seven patients with myelodysplastic syndromes. The patients with myelodysplastic syndromes had larger increases in granulocyte, monocyte, and reticulocyte counts than did those with aplastic anemia, and they also had increases in the numbers of eosinophils (two of seven), immature myeloid cells (two of seven), and myeloblasts (two of seven) that were not observed in patients with aplastic anemia. There was no reduction in erythrocyte transfusion requirements, and no effect was observed on platelet counts. There was only minimal toxicity consisting of transient low- back discomfort, anorexia, myalgias/arthralgias, and low-grade fever. Our data suggest that GM-CSF is well tolerated and is more likely to result in elevations of blood counts in patients with myelodysplasia than in patients with aplastic anemia, but the role of GM-CSF therapy in these disorders remains to be determined.     

The effect of recombinant human granulocyte macrophage colony- stimulating factor on neutrophil activation in patients with refractory carcinoma

Patients with refractory carcinoma were treated with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) by intravenous (IV) infusion. During the period of treatment, studies of polymorphonuclear leukocyte superoxide (O2-) release in response to formylmethionylleucylphenylalanine (fMLP) and phorbol myristate acetate (PMA) and studies of chemotaxis in response to fMLP and C5a were performed. We observed that patients receiving rhGM-CSF in vivo exhibited primed O2- release after stimulation both with fMLP and PMA. Chemotaxis, however, was not enhanced by the treatment. These data suggest that host defenses may be enhanced by this treatment and that rhGM-CSF may be a useful therapeutic adjunct in compromised patients.     

Treatment of poor-prognosis, newly diagnosed acute myeloid leukemia with ara-C and recombinant human granulocyte-macrophage colony- stimulating factor

We administered recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) (120 micrograms/m2/d by continuous intravenous [IV] infusion) to 12 patients with newly diagnosed acute myeloid leukemia (AML) at relatively high risk of early death during remission induction. GM-CSF began 3 days after completion of induction chemotherapy (ara-C 1.5 g/m2 d x 4 days by continuous IV infusion after a 3 g/m2 bolus). Rates of fatal infection (42%), pneumonia and/or sepsis (83%), and CR (50%) did not differ significantly (P less than .05) from those observed after administration of the identical chemotherapy without GM-CSF to 53 historical controls with newly diagnosed AML at similarly high risk of early death. There were no significant differences between the GM-CSF-treated and the historical groups in the time required to reach neutrophil counts of 500 or 1,000/microL after administration of chemotherapy. Four patients died of infection before they could have benefited from the earliest recovery of neutrophil count observed in patients who entered CR. Growth of leukemia after GM-CSF administration was observed in only 1 of the 8 patients who survived long enough for response to induction therapy to be fully evaluated. This observation suggests that it might be safe to undertake larger, randomized studies, perhaps using earlier administration of GM-CSF, to definitively determine the role of GM-CSF added to chemotherapy in patients with newly diagnosed AML.     

Recombinant human interleukin-3 and granulocyte-macrophage colony- stimulating factor show common biological effects and binding characteristics on human monocytes

Two human hemopoietic growth factors involved in monocytopoiesis, interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were studied for their ability to stimulate blood monocytes and to bind to the monocyte membrane. Both cytokines maintained monocyte/macrophage numbers during long-term culture and increased cell size as compared with controls. Effects on cell numbers were present at low cytokine concentrations (6 to 20 pmol/L), whereas enhanced 3H-thymidine incorporation was observed only at higher concentrations (greater than or equal to 60 pmol/L). Autoradiographic studies showed only 1% to 3% of stimulated monocytes with nuclear grains. These results suggest that the primary mechanism for IL-3 and GM-CSF-induced maintenance of monocyte/macrophage numbers in humans is through an effect on cell survival. Surface receptors for both IL-3 and GM-CSF were studied by using 125I-labeled recombinant human (rh) cytokines and performing Scatchard analyses. Both cytokines showed curvilinear Scatchard plots, and computer analyses favored a two-site binding model. High-affinity binding data for 125I rhIL-3 (Kd 7.7 to 38.2 pmol/L; receptor number/cell 95 to 580) and for 125I rhGM-CSF (Kd 4.7 to 38.9 pmol/L; receptor number/cell 8 to 67) show similar binding affinities for the two cytokines but a lower receptor number/cell for 125I rhGM-CSF. Low-affinity binding characteristics for 125I rhIL-3 (Kd 513 to 939 pmol/L; receptor number/cell 179 to 5,274) and for 125I rhGM- CSF (Kd 576 to 1,120 pmol/L; receptor number/cell 130 to 657) show a similar pattern for the two cytokines. Specificity of 125I rhIL-3 and 125I rhGM-CSF binding to monocytes was established by the ability of the homologous cytokine to inhibit binding and the inability of a range of other cytokines to compete at 100-fold excess molar concentration. It is important, however, that binding of 125I rhIL-3 was partially inhibited by rhGM-CSF and that rhIL-3 partially inhibited binding of 125I rhGM-CSF to the monocyte membrane under conditions shown to prevent receptor internalization. The degree of inhibition varied between 25% and 80% in different experiments, and quantitative inhibition experiments showed that 1,000-fold excess concentrations of competitor failed to inhibit binding of the heterologous ligand completely. These results demonstrate that human IL-3 and GM-CSF have similar effects on growth and survival of human monocytes in vitro and suggest that these and other common biological effects may be mediated either through a common receptor or through distinct receptors associated on the monocyte membrane.     

Synergistic effects of thrombopoietin and granulocyte colony- stimulating factor on neutrophil recovery in myelosuppressed mice

Severe suppression of the hematopoietic system is a major factor in limiting chemotherapy dose escalation. To determine whether a combination of human recombinant granulocyte colony-stimulating factor (G-CSF) and thrombopoietin (TPO) would alter recovery of platelets, red blood cells (RBCs), or neutrophils after myeloablative therapy, myelosuppressed mice were treated with sc injections of TPO (90 micrograms/kg), G-CSF (250 micrograms/kg). TPO plus G-CSF or vehicle and complete blood counts were measured. Marrow and spleen cells were obtained at various times and assayed for erythroid, myeloid, and megakaryocytic progenitors. The prolonged neutropenia in vehicle controls (14 days) was significantly shortened in mice treated with G- CSF or TPO for 14 days. The combination of TPO plus G-CSF further reduced the duration of neutropenia. TPO and TPO plus G-CSF treatments also significantly shortened thrombocytopenia compared to vehicle. Recovery of RBCs was also enhanced in mice treated with either G-CSF or TPO, or the combination. Furthermore, treatment with G-CSF and/or TPO hastened myeloid, erythroid, and megakaryocyte progenitor recovery compared to vehicle controls. These results show that the combination of TPO plus G-CSF acts synergistically to accelerate neutrophil recovery in myelosuppressed mice and does not compromise the platelet or RBC response to TPO therapy.     

Macrophage colony-stimulating factor and granulocyte-macrophage colony- stimulating factor stimulate the synthesis of plasminogen-activator inhibitors by human monocytes

Macrophage colony-stimulating factor (M-CSF or CSF-1) and granulocyte- macrophage CSF (GM-CSF) have been shown to increase human monocyte urokinase-type plasminogen-activator (u-PA) activity with possible consequences for cell migration and tissue remodeling; because monocyte u-PA activity is likely to be controlled in part also by the PA inhibitors (PAIs) made by the cell, the effect of M-CSF and GM-CSF on human monocyte PAI-2 and PAI-1 synthesis was investigated. To this end, elutriation-purified human monocytes were treated in vitro with purified recombinant human M-CSF and GM-CSF, and PAI-2 and PAI-1 antigen and mRNA levels measured by specific enzyme-linked immunosorbent assays and Northern blot, respectively. Each CSF could enhance the protein and mRNA levels of PAI-2 and PAI-1 at similar concentrations for each product. This similar regulation of monocyte PAI expression in response to the CSFs contrasted with that found for the effects of lipopolysaccharide, transforming growth factor-beta and a glucocorticoid. Therefore, PAIs may be modulating the effects of the CSFs on monocyte u-PA activity at sites of inflammation and tissue remodeling.     

Comparative analysis of the in vivo radioprotective effects of recombinant granulocyte colony-stimulating factor (G-CSF), recombinant granulocyte-macrophage CSF, and their combination.

The purpose of the present study was to evaluate and compare the in vivo radioprotective effects of pre-total body irradiation (TBI) conditioning with recombinant granulocyte colony-stimulating factor (rG-CSF) and recombinant granulocyte-macrophage CSF (rGM-CSF) in a large series of lethally and supralethally irradiated mice. Also analyzed were the radioprotective effects of simultaneous as well as sequential combinations of rG-CSF and rGM-CSF. Our findings in 1,180 mice provide direct evidence that in vivo administration of rG-CSF or rGM-CSF before TBI protects a significant fraction of mice from the lethal effects of LD100/30 TBI. At equivalent doses, rG-CSF displayed a more potent radioprotective activity than rGM-CSF. Not only was rG-CSF radioprotective at much smaller doses than rGM-CSF, the survival rate after lethal TBI was also significantly higher in mice receiving optimally radioprotective doses of rG-CSF as compared with mice receiving optimally radioprotective doses of rGM-CSF. Pretreatment of mice with rGM-CSF markedly attenuated the radioprotective affects of rG-CSF in lethally as well as supralethally irradiated mice. Pretreatment with rG-CSF followed by rGM-CSF was slightly more effective than rG-CSF alone in supralethally irradiated mice but not in lethally irradiated mice. Notably, marked differences among different strains of mice were noted regarding the optimally radioprotective doses of rG-CSF or rGM-CSF as well as probability of survival and median survival time after lethal or supralethal TBI. This report confirms and extends previous studies concerning the potential of cytokines in prevention or therapy of lethal radiation injury.     

Effects of in vivo recombinant methionyl human granulocyte colony- stimulating factor on the neutrophil response and peripheral blood colony-forming cells in healthy young and elderly adult volunteers

Recombinant granulocyte colony stimulating factor (G-CSF) was administered daily for 14 days to healthy young (Y) (20 to 30 years) and elderly (O) (70 to 80 years) volunteers to evaluate the effects of age on the neutrophil (polymorphonuclear leukocytes, PMN) responses. Thirty-eight volunteers were randomized to receive 0 micrograms, 30 micrograms, or 300 micrograms per day. Baseline neutrophil counts (ANC), peak ANCs, and the rate of attaining the peak ANC were similar in both age groups at both doses. The peak ANC was increased 5-fold at 30 micrograms and 15-fold at 300 micrograms in both the young and elderly. Daily tests of PMN function, as measured by an automated chemiluminescence system, showed nearly identical responses to several agonists for both age groups. Marrow proliferative activity as reflected by the percentage of cells in the marrow neutrophil mitotic pool also increased similarly for both age groups at both doses. In contrast, there was an age-related change in blood colony formation as measured by the blood CFU-GM assay. Compared with controls at the 30 micrograms dose, mean colony formation was increased 2-fold in the young versus no change in the elderly and at the 300 micrograms dose 24- fold in the young versus 12-fold in the elderly. These studies indicate that neutrophil responses to rhG-CSF are equivalent in healthy young and elderly volunteers but the mobilization of progenitor cells, as measured by the CFU-GM assay appears to differ substantially.     

The effect of recombinant human granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity in chronic severe neutropenia

STUDY OBJECTIVE: To define the clinical and hematologic effects of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on patients with chronic severe neutropenia. DESIGN: Open-label, phase II study of rhGM-CSF. SETTING: Inpatient hematology and surgery clinic at a university medical center. PATIENTS: Four consecutive patients with chronic severe neutropenia, which in two cases was complicated by severe infection, in one case by perianal fistula, and in one case by complete rectal prolapse. Two patients had chronic idiopathic neutropenia; one patient had congenital neutropenia (myelokathexis); and one patient had autoimmune neutropenia. INTERVENTIONS: The rhGM-CSF was given intravenously or subcutaneously at starting dosages of 150 to 1000 micrograms/m2 body surface area.d for 12 to 14 consecutive days. Two patients received a second course of daily rhGM-CSF treatment after a nontreatment interval of 14 to 20 days. MEASUREMENTS AND MAIN RESULTS: In all four patients, the absolute neutrophil counts increased from less than 0.25 x 10(9)/L to 3.2 to 19.2 x 10(9)/L within 2 weeks of beginning rhGM-CSF therapy. Two patients had life-threatening infections that resolved during therapy. The two other patients had major ano-rectal surgery during rhGM-CSF treatment and had no postoperative infections. CONCLUSIONS: In patients with chronic neutropenia, rhGM-CSF may increase neutrophil counts. This therapy may be a useful adjunct to antibiotic therapy for patients with infection and perioperatively for patients having anorectal surgery.