G-CSF administration results in thrombocytopenia by inhibiting the differentiation of hematopoietic progenitors into megakaryocytes.

Hematopoietic stem cell transplantation (HSCT) plays an important role in the therapy of hematological malignancies and some nonmalignant diseases. Granulocyte colony-stimulating factor (G-CSF) is generally used to mobilize and collect hematopoietic stem cells from donors and accelerate neutrophil recovery in transplantation recipients. However, less attention has been paid to the fact that G-CSF administration might result in thrombocytopenia and enhance bleeding risk in HSCT. In this study, we investigated the effects of G-CSF on platelet counts in healthy mice and mice that received bone marrow transplantation. It was observed that G-CSF administration induced thrombocytopenia in healthy mice and aggravated thrombocytopenia in mice that received bone marrow transplantation. Furthermore, we analyzed the regulatory effects of G-CSF on the differentiation of hematopoietic progenitors and megakaryocytes, and activation of platelets and endothelial cells. The results reveal that G-CSF administration causes thrombocytopenia mainly by inhibiting the differentiation of common myeloid progenitors and megakaryotic erythroid progenitors into megakaryocytes and platelet formation but not through enhancing activation of platelets or endothelial cells and following platelet consumption. Collectively, G-CSF administration can result in thrombocytopenia in hematopoietic stem cell donors and exacerbate existing thrombocytopenia in transplantation recipients. More attention should be paid to bleeding risk of G-CSF administration in HSCT, especially autologous HSCT.

Retinal Toxicity of Intravitreal Granulocyte Colony-Stimulating Factor in Rabbit Eyes.

PURPOSE: Granulocyte colony-stimulating factor (G-CSF) has potential ocular neuroprotective effects. The aim of this study was to evaluate the retinal toxicity of intravitreal G-CSF in rabbit eye. METHODS: Eight New Zealand albino rabbits, weighing between 2 and 3 kg, were selected for this study. The initial concentration of G-CSF (300 µg/0.5 ml) was titrated to obtain different concentrations of 45 µg, 30 µg, 15 µg, and 7.5 µg in 0.1 ml. Each concentration was injected into two rabbit eyes. For each dose, dextrose was injected in one contralateral eye and the other fellow eye remained non-injected. Electroretinographic (ERG) testing was performed before and 4 weeks after injections. The rabbits were euthanized and the eyes were enucleated 4 weeks after injections and examined using light microscopy and immunohistochemistry. RESULTS: One rabbit with the injected dosage of 7.5 µg died at the first post-injection day. No sign of intraocular toxicity was found in clinical examination in other rabbits. A significant decrease in at least one of the a- or b-wave measurements of scotopic or photopic responses was found in 45 µg, 15 µg, and 7.5 µg injected eyes. Eyes with an intravitreal injection dosage of 30 µg G-CSF did not have significant changes compared to the baseline values. Histologic and immunohistochemistric studies were unremarkable for pathologic changes in all injected eyes. CONCLUSION: While histologic and immunohistochemistric examinations revealed no toxicity in all G-CSF-injected eyes, significant ERG changes were observed in all doses except for the dose of 30 µg/0.1 ml.

Minocycline alleviates behavioral deficits and inhibits microglial activation induced by intrahippocampal administration of Granulocyte-Macrophage Colony-Stimulating Factor in adult rats.

Some evidence has shown an increased number of activated microglial cells in patients with schizophrenia. It is hypothesized that activated microglia may contribute to the pathogenesis of schizophrenia. We injected saline or Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) into the ventral hippocampus in adult Sprague-Dawley rats via micro-pump; at the same time, the rats were intragastrically administrated with saline or minocycline once a day for 14 consecutive days. Then, behavioral tests were examined and microglia were assessed using immunohistochemistry method. GM-CSF-injected group showed significant behavioral deficits (hyperlocomotion, social interaction deficits, prepulse inhibition (PPI) deficits). There was a dramatic increase of the number of activated microglial cells in the hippocampus and other brain regions such as cerebral cortex and thalamus compared with those in saline-injected group in immunohistochemistry. Minocycline was able to ameliorate deficits of social interaction and PPI but not hyperlocomotion. Minocycline was also able to inhibit the microglial activation. In conclusion, intrahippocampal administration of GM-CSF in adult rats may serve as a potential schizophrenia animal model, which may be related with the microglia hypothesis of schizophrenia.

A truncation mutant of Csf3r cooperates with PML-RARα to induce acute myeloid leukemia in mice.

Severe congenital neutropenia is associated with a marked propensity to develop myelodysplasia or acute myeloid leukemia (AML). Truncation mutations of CSF3R, encoding the granulocyte colony-stimulating factor receptor (G-CSFR), are associated with development of myelodysplasia/AML in severe congenital neutropenia. However, a causal relationship between CSF3R mutations and leukemic transformation has not been established. Herein, we show that truncated G-CSFR cooperates with the PML-RARα oncogene to induce AML in mice. Expression of truncated G-CSFR significantly shortens the latency of AML in a G-CSF-dependent fashion and it is associated with a distinct AML presentation characterized by higher blast counts and more severe myelosuppression. Basal and G-CSF-induced signal transducer and activator of transcription 3, signal transducer and activator of transcription 5, and extracellular signal-regulated kinase 1/2 phosphorylation were highly variable but similar in leukemic blasts expressing wild-type and truncated G-CSFR. These data provide new evidence suggesting a causative role for CSF3R mutations in human AML.

Effects of granulocyte-colony stimulating factor on chromosome aneuploidy and replication asynchrony in healthy peripheral blood stem cell donors.

As peripheral blood has surpassed bone marrow as a predominant source of stem cells for transplantation, use of the cytokine granulocyte colony-stimulating factor (G-CSF) to mobilize peripheral blood stem cells (PBSCs) is increasing. Issues regarding potential genotoxic effects of even short-term, low-dose G-CSF treatment for the healthy donors have been raised. To address the question of chromosomal instability, we used FISH to evaluate the peripheral blood lymphocytes of 22 PBSC donors and 22 matched controls at 5 time points over a 12-month period. The specimens obtained were a pre-G-CSF, followed by collections at the time of PBSC harvest (days 5-7) and at 2, 6, and 12 months after donation. Eight additional PBSC donors provided a single sample at 12 months. Nine loci (mapped to chromosomes 7, 8, 9, 17, 21, and 22) were evaluated for aneuploidy, including 3 mapped to chromosome 7 because of the specific relevance of monosomy 7. Replication timing was evaluated for chromosome 15 and 17 loci. No evidence was found of G-CSF-induced chromosomal instability. This work supports the epidemiologic data that have demonstrated no increased risk for hematologic malignancies in G-CSF-primed PBSC donors.

Chronic toxicity of a novel recombinant human granulocyte colony-stimulating factor in rats.

OBJECTIVE: To assess the severity and reversibility of the chronic toxicity of a novel recombinant human granulocyte colony-stimulating factor (rhG-CSFa) in rats and the dose-effect relationship. METHODS: A total of 100 Sprague-Dawley rats (equal numbers of male and female) were randomly divided into five groups (20 rats in each group): four groups were treated with rhG-CSFa at 500, 100, 10, 1 µg/kg, respectively, and one group was treated with vehicle only to serve as the control. The rats were received subcutaneous injections of rhG-CSFa or vehicle daily for 13 weeks. During the course of the chronic toxicity study, the physical status, body weight, and food consumption were monitored. Half of the rats in each group (n = 10) were sacrificed after the last rhG-CSFa administration, and the other half were sacrificed at five weeks after the last rhG-CSFa administration. Urinalyses, blood biochemistry, hematological analysis, histopathological examination, and immunological tests were performed for each of the rats. RESULTS: The hematological analyses revealed that the mean white blood cells count, neutrophils count, and neutrophils percentage were increased in male rats at the dose of 10 µg/kg or higher, and these were related with the biological activity of rhG-CSFa. Some small abnormalities were observed in the spleen of a few rats when used highest dose (500 µg/kg, a dosage of 200 folds higher than the normal clinical dosage), but these abnormalities were recovered within 5-week recovery period. No other rhG-CSFa-related abnormalities were observed in this chronic toxicity study. CONCLUSION: No significant toxicity and immunogenicity are observed with rhG-CSFa administration to rats in the chronic toxicity studies.

Granulocyte-colony stimulating factor (G-CSF) induces mechanical hyperalgesia via spinal activation of MAP kinases and PI3K in mice.

Granulocyte-colony stimulating factor (G-CSF) is a current pharmacological approach to increase peripheral neutrophil counts after anti-tumor therapies. Pain is most relevant side effect of G-CSF in healthy volunteers and cancer patients. Therefore, the mechanisms of G-CSF-induced hyperalgesia were investigated focusing on the role of spinal mitogen-activated protein (MAP) kinases ERK (extracellular signal-regulated kinase), JNK (Jun N-terminal Kinase) and p38, and PI(3)K (phosphatidylinositol 3-kinase). G-CSF induced dose (30-300 ng/paw)-dependent mechanical hyperalgesia, which was inhibited by local post-treatment with morphine. This effect of morphine was reversed by naloxone (opioid receptor antagonist). Furthermore, G-CSF-induced hyperalgesia was inhibited in a dose-dependent manner by intrathecal pre-treatment with ERK (PD98059), JNK (SB600125), p38 (SB202190) or PI(3)K (wortmanin) inhibitors. The co-treatment with MAP kinase and PI(3)K inhibitors, at doses that were ineffective as single treatment, significantly inhibited G-CSF-induced hyperalgesia. Concluding, in addition to systemic opioids, peripheral opioids as well as spinal treatment with MAP kinases and PI(3)K inhibitors also reduce G-CSF-induced pain.

The clinical outcome of FLAG chemotherapy without idarubicin in patients with relapsed or refractory acute myeloid leukemia.

A refractory and resistant disease to conventional induction chemotherapy and relapsed disease are considered as the most important adverse prognostic factors for acute myeloid leukemia (AML). Sixty-one patients (median age, 33.6 yr) with relapsed or refractory AML were treated with the FLAG regimen that consisted of fludarabine (30 mg/m(2), days 1-5), cytarabine (2.0 g/m(2), days 1-5) and granulocyte colony-stimulating factor. Of the treated patients 29 patients (47.5%) achieved complete remission (CR). Higher CR rates were observed for patients with a first or second relapse as compared to patients with a primary refractory response or relapse after stem cell transplantation (HSCT). There was a significant difference in the response rates according to the duration of leukemia-free survival (pre-LFS) before chemotherapy (P=0.05). The recovery time of both neutrophils (> or =500/microL) and platelets (> or =20,000/microL) required a median of 21 and 18 days, respectively. Treatment-related mortality (TRM) occurred in seven patients (11.4%), of which 71.4% of TRM was caused by an invasive aspergillosis infection. After achieving CR, 18 patients underwent consolidation chemotherapy and six patients underwent allogeneic HSCT. In conclusion, FLAG chemotherapy without idarubicin is a relatively effective and well-tolerated regimen for relapsed or refractory AML and the use of FLAG chemotherapy has allowed intensive post-remission therapy including HSCT.

A prospective study of G-CSF primed bone marrow as a stem-cell source for allogeneic bone marrow transplantation in children: a Pediatric Blood and Marrow Transplant Consortium (PBMTC) study.

A prospective multicenter trial was conducted to evaluate the safety and feasibility of granulocyte colony-stimulating factor (G-CSF)-primed bone marrow (G-BM) in children receiving allogeneic bone marrow transplantation (BMT). A total of 42 children with a median age of 9.8 years (range, 0.8-17 years) were enrolled. Donors with median age of 9.2 years (range, 1.1-22 years) received 5 microg/kg per day of subcutaneous G-CSF for 5 consecutive days. BM was harvested on the fifth day. No donor experienced complications related to G-CSF administration or marrow har-vest. Median nucleated (NC) and CD34 cells infused was 6.7 x 10(8)/kg (range, 2.4-18.5 x 10(8)/kg) and 7.4 x 10(6)/kg (range, 2-27.6 x 10(6)/kg), respectively. Neutrophil and platelet engraftment was at a median of 19 days (range, 13-28 days) and 20 days (range, 9-44 days), respectively. A total of 13 (32%) patients developed grade 2 graft-versus-host disease (GVHD), and 5 (13%) of 40 evaluable patients developed chronic GVHD (3 limited and 2 extensive). Higher cell dose was not associated with increased risk of acute or chronic GVHD. Overall survival and event-free survival at 2 years were 81% and 69%, respectively. Collection of G-BM from pediatric donors is safe, and can result in high NC and CD34 cell doses that facilitate engraftment after myeloablative BMT without a discernable increase in the risk of GVHD.

Granulocyte colony-stimulating factor and granulocyte macrophage colony-stimulating factor exacerbate atherosclerosis in apolipoprotein E-deficient mice.

BACKGROUND: Recent studies have suggested a potential contribution of bone marrow-derived progenitor cells to vascular repair. Preliminary clinical studies have explored the possibility that mobilization of progenitor cells with granulocyte macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) can affect vascular repair. However, it is not known whether the short-term administration of G-CSF or GM-CSF exerts beneficial effects on atherosclerosis. METHODS AND RESULTS: Apolipoprotein E-deficient mice were treated with either GM-CSF or G-CSF at a dose of 10 microg x kg(-1) x d(-1) s.c. administered daily for 5 days per week on alternating weeks for a total of 20 doses over an 8-week treatment period. We found that in animals maintained on a high-fat diet, both G-CSF and GM-CSF actually demonstrated an increase in atherosclerotic lesion extent. The increase in atherosclerotic extent was not associated with an increase in either inflammatory cells or expression of proinflammatory genes. Interestingly, adventitial vascularity significantly increased, suggesting a mechanistic role for vasa vasorum neovascularization. CONCLUSIONS: These findings demonstrate that in this animal model of atherosclerosis, not only did administration of G-CSF or GM-CSF fail to demonstrate any beneficial therapeutic effect, but both resulted in a worsening of atherosclerosis.

Pegfilgrastim supports delivery of FEC-100 chemotherapy in elderly patients with high risk breast cancer: a randomized phase 2 trial.

This randomized phase 2 study explored the feasibility of delivering four to six cycles of the dose-intensified regimen FEC-100 (5-fluorouracil, epirubicin, and cyclophosphamide) to elderly patients with stage II-III breast cancer, using pegfilgrastim for neutrophil support. Sixty patients aged 65-77 years received single 6mg doses of pegfilgrastim on day 2 of FEC-100, either as primary prophylaxis (all cycles: PP), or as secondary prophylaxis (all cycles following a neutropenic event: SP). Neutropenic events (a composite endpoint that included grade 3 neutropenia+fever, grade 4 neutropenia, infectious complication requiring systemic anti-infectives and chemotherapy dose delay/reduction) occurred in 24/30 (80%) of the PP and 21/29 (72%) of the SP group in the first cycle. Most patients received all chemotherapy cycles at full dose on schedule (26/30 [87%] PP; 20/29 [69%] SP). These data indicate that delivery of FEC-100 is feasible with pegfilgrastim support in elderly breast cancer patients.

Prophylactic human granulocyte colony-stimulating factor after induction therapy in pediatric acute myeloid leukemia.

Children with acute myelogenous leukemia (AML) have a high risk of infectious complications that might be reduced by prophylactic granulocyte colony-stimulating factor (G-CSF). However, G-CSF could induce AML blast proliferation. The prospective randomized trial AML-BFM 98 investigated the impact of G-CSF on hematopoetic recovery and infectious complications (primary endpoints) and on outcome (secondary endpoint) in children (aged 0-18 years) with de novo AML. Patients with more than 5% blasts in day-15 bone marrow or with FAB M3 were not included. Between 1998 and 2003, 161 children with AML were randomized to receive G-CSF after inductions 1 and 2, whereas 156 patients were assigned to the control group. Time of neutropenia after inductions 1 and 2 was significantly shorter in the G-CSF group (23 vs 18 days and 16 vs 11 days; P=.02 and=.001, respectively). G-CSF did not decrease the incidence of febrile neutropenia (72 and 36 patients vs 78 and 37 patients, respectively), microbiologically documented infections (27 and 25 patients vs 36 and 19 patients, respectively) and infection-associated mortality (5 vs 2 patients). Both groups had similar 5-year event-free survival (EFS; 59%+/-4% vs 58%+/-4%). Since G-CSF does not influence the risk of infectious complications or outcome in children undergoing therapy for AML, one cannot advocate the routine use of G-CSF in this patient group.

Roles of leukocytosis and cysteinyl leukotriene in polymorphonuclear leukocyte-dependent plasma extravasation.

The PMN-dependent plasma extravasation is a major mechanism of permeability enhancement in acute inflammation. To reveal the pathophysiological significance of the PMN-dependent plasma extravasation, we prepared a systemic leukocytotic guinea pig model by a daily injection of recombinant human (rh)G-CSF. The extent of the PMN-dependent plasma extravasation, regarded as the late-phase permeability induced by an intradermal injection of zymosan-activated guinea pig plasma (ZAP) or of rhC5a, clearly correlated to the circulating PMN number. The augmentation of local response following the systemic response seemed to be the characteristic feature of the PMN-dependent plasma extravasation. We then revealed the molecular mechanism of the PMN-dependent plasma extravasation. Neither the antihistaminic agent diphenhydramine, nor the bradykinin B2 receptor antagonist, HOE140, affected the ZAP-induced, late-phase extravasation. In contrast to this, pretreatment with an antagonist of cysteinyl leukotriene (cys-LT) 1 receptor, pranlukast, significantly reduced the late-phase extravasation. Similarly, it was reduced by pretreatment with a 5-lipoxygenase inhibitor, MK-886, indicating the participation of cys-LTs in the PMN-dependent plasma extravasation. Histologically, pretreatment with pranlukast or MK-886 did not affect the ZAP-induced PMN infiltration. Consistently, a combined treatment with pranlukast and diphenhydramine completely suppressed the early-phase extravasation. As pranlukast pretreatment did not affect plasma extravasation induced by mast cell degranulation, and depletion of platelets did not influence the pranlukast-inhibitable plasma extravasation induced by rhC5a injection, cys-LTs are most likely produced by transcellular biosynthesis involving PMNs and vascular wall cells.

Feasibility and safety of G-CSF administration to induce bone marrow-derived cells mobilization in patients with end stage liver disease.

BACKGROUND/AIMS: To evaluate feasibility, safety and pattern of bone marrow-derived cells (BMC) mobilization in patients with end stage liver cirrhosis following granulocyte-colony stimulating factor (G-CSF) administration. METHODS: Eight patients with severe liver cirrhosis (Child-Pugh score B-C, spleen diameter less than 170 mm) were included. They were treated with G-CSF (5 microg/kg b.i.d for three consecutive days) to mobilize BMC, evaluated as circulating CD34+ve cells (flow cytometry) and myeloid CFU-GM progenitors (in vitro colony growth assay). Co-expression in CD34+ve cells markers of differentiation (Thy1, CD133, CXCR4, c1qRp) were investigated on CD34+ve cells by double direct immunofluorescence. Data from 40 healthy haematopoietic stem cell donors were used as controls. RESULTS: Mobilization of CD34+ve cells occurred in all patients. It was paralleled by expansion of circulating CFU-GM progenitors. Circulating CD34+ve cells co-expressed epithelial and stem cell markers in both cirrhotics and volunteer stem cell donors. G-CSF was well tolerated, no adverse event occurred, a significant reversible increase of splenic longitudinal diameter was observed. CONCLUSIONS: (i) G-CSF mobilization of BMC co-expressing epithelial and stem markers occurred in all cirrhotic patients; (ii) splenomegaly up to 170 mm does not prevent safe BMC mobilization following G-CSF in patients with end stage liver disease; (iii) mobilized BMC may represent an easy immature cell source potentially useful for novel approaches for liver regeneration.

[Side effect of granulocytic colony-stimulating factor on the structure and function of mouse liver].

AIM: To study effects of granulocytic colony-stimulating factor (G-CSF) on morphology and function of mouse liver. MATERIAL AND METHODS: G-CSF was injected subcutaneously to mice in a daily dose 200 mcg/kg for 8 days. Peripheral blood formed elements percentage was estimated 24 hours, 7 and 28 days after the last injection of G-CSF. Bilirubin level, activity of aspartate- and alaninaminotransferase (AST, ALT) were studied in the blood serum. Structure of hepatic parenchyma was studied on histological sections stained with hematoxilin-eosine. The sections were stained with picro-sirius red for detection of collagen. RESULTS: G-CSF raised the count of neutrophilic granulocytes in peripheral blood. Maximal number of neutrophils in blood was observed on day 7 after discontinuation of G-CSF. At the same time, hepatocytes were dystrophic and partially necrotic. The lumina of many vessels of hepatic lobules were filled with erythrocytes. Going in parallel hemolysis of erythrocytes corresponded to biochemical indices of functional activity of the liver. Content of AST, but not ALT, increased 2-3-fold. Vascular walls were thick due to active synthesis of collagen. Four weeks after the last G-CSF injection vascular lumina were free of blood, but vascular epithelium layer was thick. CONCLUSION: Side effects of G-CSF were found. They affected physiological status of mouse liver causing necrosis of hepatosytes, venous plethora and red cell hemolysis. Maximal changes were registered on day 7 after discontinuation of G-CSF. The inflammatory process (collagen synthesis) continues after 4 weeks upon discontinuation of G-CSF.

Reduced risk of acute GVHD following mobilization of HLA-identical sibling donors with GM-CSF alone.

We retrospectively reviewed the results of transplanting peripheral blood progenitor cell (PBPC) allografts from HLA-matched sibling donors mobilized using various hematopoietic cytokines. Patients had received allografts mobilized with Granulocyte colony-stimulating factor (G-CSF) (G, N = 65) alone, G plus Granulocyte-macrophage colony stimulating factor (GM-CSF) (G/GM, N = 70), or GM-CSF alone at 10 or 15 microg/kg/day (GM, N = 10 at 10 microg/kg/day and 21 at 15 microg/kg/day). The CD34+ and CD3+ cell content of grafts were significantly lower following GM alone compared to G alone (P < 0.001 and 0.04, respectively). Nonhematopoietic toxicity observed in donors precluded dose escalation of GM-CSF beyond 10 microg/kg/day. Hematopoietic recovery was similar among all three groups. Grades II-IV acute graft-versus-host disease (GVHD) was observed in only 13% of patients in the GM alone group compared to 49 and 69% in the G alone or G/GM groups, respectively (P < 0.001). In a multivariate analysis, receipt of PBPC mobilized with GM alone was associated with a lower risk of grades II-IV acute GVHD (hazard ratio 0.21; 95% CI 0.073, 0.58) compared to G alone or G/GM. There were no differences in relapse risk or overall survival among the groups. Donor PBPC grafts mobilized with GM-CSF alone result in prompt hematopoietic engraftment despite lower CD34+ cell doses and may reduce the risk of grades II-IV acute GVHD following HLA-matched PBPC transplantation.

Early deaths and treatment-related mortality in children undergoing therapy for acute myeloid leukemia: analysis of the multicenter clinical trials AML-BFM 93 and AML-BFM 98.

PURPOSE: The rates of early death (ED) and treatment-related mortality (TRM) are unacceptably high in children undergoing intensive chemotherapy for acute myeloid leukemia (AML). Better strategies of supportive care might help to improve overall survival in these children. PATIENTS AND METHODS: In a retrospective study, we analyzed incidence, clinical features, and risk factors for lethal complications of 901 children enrolled onto the multicenter trials Acute Myeloid Leukemia-Berlin-Frankfurt-Muenster (AML-BFM) 93 and AML-BFM 98. RESULTS: One hundred four patients (11.5%) enrolled onto the clinical trials AML-BFM 93 and AML-BFM 98 died shortly after diagnosis or as a result of treatment-related complications. Thirty-two patients (3.5%) died before (six patients) or during (26 patients) the first 14 days of treatment, mainly as a result of bleeding or leukostasis. Low performance status, hyperleukocytosis, and French-American-British type M5 were the main risk factors for a lethal event before day 15. After day 15, the predominant causes of death were complications caused by infections, particularly bacterial and fungal infections. The incidence of lethal infections was highest during induction therapy and decreased thereafter. When comparing both clinical trials, significantly fewer patients died within the first 6 weeks in AML-BFM 98 than in AML-BFM 93 (14 [3.5%] of 430 patients v 35 [7.4%] of 471 patients; P = .01). CONCLUSION: To reduce the high incidence of ED and TRM in children with AML, early diagnosis and adequate treatment of complications are needed. Children with AML should be treated in specialized pediatric cancer centers only. Prophylactic and therapeutic regimens for better treatment management of bleeding disorders and infectious complications have to be assessed in future trials to ultimately improve overall survival in children with AML.

Randomized comparison of granulocyte colony-stimulating factor versus granulocyte-macrophage colony-stimulating factor plus intensive chemotherapy for peripheral blood stem cell mobilization and autologous transplantation in multiple myeloma.

Autologous peripheral blood stem cell transplantation for multiple myeloma offers higher response rates and improved survival compared with conventional chemotherapy. However, successful autografting requires effective cytoreduction and rapid hematologic reconstitution. We conducted a prospective randomized clinical trial to assess the efficacy of 2 cycles of priming chemotherapy with either granulocyte colony-stimulating factor (G-CSF) or granulocyte-macrophage colony-stimulating factor (GM-CSF) for peripheral blood stem cell mobilization followed by autologous transplantation. The major study end points were the comparative utility of G-CSF versus GM-CSF, the percentage of patients achieving complete response after transplantation, and overall and progression-free survival. Priming chemotherapy included cyclophosphamide (4 g/m2), mitoxantrone (8 g/m2 every day for 2 days), and dexamethasone (20 mg/m2 every 12 hours for 2 days) followed by randomization to either G-CSF or GM-CSF daily until completion of leukapheresis. Conditioning for transplantation included cyclophosphamide (75 mg/kg every day for 2 days) plus total body irradiation (165 cGy twice daily for 3 days), and patients received maintenance immunotherapy with interferon alpha. Seventy-two patients were randomized, and 64 underwent autologous transplantation. The median age at transplantation was 52 years, and the median time from diagnosis to transplantation was 10 months; 58% of the patients had received >4 cycles of pretransplantation chemotherapy. The median number of CD34+ cells obtained after mobilization was 16.4 x 10(6)/kg in the G-CSF arm versus 12.8 x 10(6)/kg in the GM-CSF arm (P = .8). Neutrophil recovery was faster in the G-CSF group after both cycle 1 (median, 13 days with G-CSF and 16 days with GM-CSF; P < .01) and cycle 2 (median, 13 days versus 17 days in the 2 groups, respectively; P = .03). Although platelet recovery was similar after cycle 1, platelet recovery to >100000/microL was notably faster in the G-CSF group both after cycle 2 and after transplantation (P = .03). Response and overall and disease-free survival were similar in both cohorts. Overall, 23% of the patients achieved a complete response after priming chemotherapy, which improved to 33% after transplantation. An additional 47% attained a partial response after transplantation, for a total response rate of 80%. With a median follow-up of 2 years (range, 0.7-8 years), the overall survival was 88% (95% confidence interval [CI], 80%-96%) at 1 year and 65% (95% CI, 51%-79%) at 3 years. Progression-free survival was 73% (95% CI, 62%-84%) at 1 year and 40% (95% CI, 26%-54%) at 3 years. Relapse or progressive disease was the most common cause of death (25 [83%] of 30 deaths). We conclude that mobilization with chemotherapy plus G-CSF versus GM-CSF results in similar CD34+ progenitor collections, even in patients exposed to multiple cycles of alkylator-based chemotherapy. Earlier neutrophil and platelet recovery was seen with G-CSF priming. Two cycles of priming chemotherapy plus autologous transplantation yields survival rates similar to those in published reports, including those using tandem transplantation.

Adjunctive efficacy of granulocyte colony-stimulating factor on treatment of Pseudomonas aeruginosa pneumonia in neutropenic and non-neutropenic hosts.

OBJECTIVES: Granulocyte colony-stimulating factor (G-CSF) stimulates proliferation of neutrophils and enhances their phagocytic and microcidal activity. Increasing resistance to existing antibacterials and the dearth of new alternatives have complicated the treatment of Gram-negative infections. The aim of this study was to evaluate the efficacy of G-CSF in the treatment of Pseudomonas aeruginosa pneumonia when administered in combination with ceftazidime in both neutropenic and non-neutropenic hosts. METHODS: A group of mice were rendered neutropenic with cyclophosphamide. Pneumonia was induced by intratracheal instillation of approximately 5 x 10(7) cfu/mL and approximately 5 x 10(9) cfu/mL (LD(100)) of the organism to neutropenic and non-neutropenic mice, respectively. Two hours after inoculation, the mice received normal saline and 5% dextrose, G-CSF (300 micro g/kg per day x 3 days), ceftazidime (2000 mg/kg x 2 doses) or a combination of G-CSF and ceftazidime. Survival was monitored at different time points for 5 days. RESULTS: Treatment with G-CSF showed a dose-dependent increase in survival from 50 to 300 micro g/kg. In neutropenic mice, survival was markedly better in the G-CSF + ceftazidime group compared with controls (P = 0.0001), G-CSF (P = 0.0002) or ceftazidime (P = 0.0172). In non-neutropenic mice, survival in the G-CSF + ceftazidime group (20%) was significantly higher than in the control and G-CSF groups (P = 0.0001) but not significantly higher than ceftazidime alone (9%) (P > 0.05). CONCLUSIONS: G-CSF administered in combination with antibiotic after onset of severe P. aeruginosa pneumonia may improve therapeutic outcome and this suggests a new treatment option in the management of pneumonia especially in neutropenic patients.

Use of recombinant human growth hormone (rhGH) plus recombinant human granulocyte colony-stimulating factor (rhG-CSF) for the mobilization and collection of CD34+ cells in poor mobilizers.

The activity of recombinant human growth hormone (rhGH) in enhancing CD34(+) cell mobilization elicited by chemotherapy plus recombinant human granulocyte colony-stimulating factor (rhG-CSF) was evaluated in 16 hard-to-mobilize patients, that is, those achieving a peak of circulating CD34+ cells 10/microL or less, or a collection of CD34(+) cells equal to or less than 2 x 10(6)/kg. Patients who had failed a first mobilization attempt with chemotherapy plus rhG-CSF (5 microg/kg/d) were remobilized with chemotherapy plus rhG-CSF and rhGH (100 microg/kg/d). As compared with rhG-CSF, the combined rhGH/rhG-CSF treatment induced significantly higher (P < or =.05) median peak values for CD34(+) cells/microL (7 versus 29), colony-forming cells (CFCs)/mL (2154 versus 28,510), and long-term culture-initiating cells (LTC-ICs)/mL (25 versus 511). Following rhG-CSF and rhGH/rhG-CSF, the median yields of CD34(+) cells per leukapheresis were 1.1 x 10(6)/kg and 2.3 x 10(6)/kg (P < or =.008), respectively; the median total collections of CD34(+) cells were 1.1 x 10(6)/kg and 6 x 10(6)/kg (P < or =.008), respectively. No specific side effect could be ascribed to rhGH, except a transient hyperglycemia occurring in 2 patients. Reinfusion of rhGH/rhG-CSF-mobilized cells following myeloablative therapy resulted in prompt hematopoietic recovery. In conclusion, our data demonstrate that in poor mobilizers addition of rhGH to rhG-CSF allows the patients to efficiently mobilize and collect CD34(+) cells with maintained functional properties.