Safety and efficacy of therapeutic early onset granulocyte transfusions in pediatric patients with neutropenia and severe infections

BACKGROUND: Bacterial and fungal infections in profound neutropenia after chemotherapy are associated with high mortality despite appropriate antibacterial and antifungal treatment. Granulocyte transfusions are used as a therapeutic addendum, but concern regarding pulmonary reactions often results in delayed use in clinical practice. Accordingly, many patients are already at advanced stages of their infectious disease once granulocytes are transfused. Thus, a prospective Phase II trial was conducted to test the safety and efficacy of therapeutic early-onset granulocyte transfusions in immunocompromised children with neutropenia and severe infections. STUDY DESIGN AND METHODS: Twenty-seven children with hematologic disorder or malignancy and severe neutropenia with clinically and/or microbiologically documented severe infection unresponsive to standard treatment were included. They received granulocyte colony-stimulating factor (G-CSF)-elicited, crossmatched granulocyte concentrates every other day until complete recovery from infection was documented. RESULTS: A median of two granulocyte transfusions with a median of 8 x 10(8) granulocytes per kilogram of body weight were administered. All transfusions were well tolerated, and no pulmonary symptoms were observed. A total of 92.6 percent of our patients were able to clear their initial infection, and 81.5 percent were alive and without signs or symptoms of their infection 1 month later. All six children with aspergillosis cleared their infection. CONCLUSIONS: G-CSF-elicited, crossmatched granulocyte concentrates are a safe and efficient therapeutic addendum in immunocompromised children with prolonged neutropenia and severe infections. Early transfusion of granulocyte concentrates can lead to an overall response rate of 92.6 percent without adverse events. Randomized clinical trials with an early-onset design are required to determine appropriate clinical applications.     

Persistent, therapeutically relevant levels of human granulocyte colony-stimulating factor in mice after systemic delivery of adeno-associated virus vectors.

Adeno-associated virus (AAV) vectors have been shown to preferentially transduce hepatocytes after systemic administration in adult mice and to provide long-term expression of introduced genes. One application of this technology would be for the production of granulocyte colony-stimulating factor (G-CSF), which increases mature neutrophil numbers in humans and in animals, and has therapeutic effects in disorders featuring chronic neutropenia, including cyclic, severe congenital, and idiopathic neutropenia, and glycogen storage disease type Ib. We have treated mice by tail vein injection of AAV vectors encoding human G-CSF, and have detected high G-CSF levels and marked elevation of neutrophil counts for at least 5 months. A therapeutically relevant amount of G-CSF production was obtained when the liver-specific mouse albumin promoter-enhancer was used to drive G-CSF expression. In mice receiving higher amounts of vector, plasma levels of human G-CSF gradually increased over 3 weeks to high concentrations, whereas for lower amounts human G-CSF remained at initial, low levels. The previously observed effect of gamma irradiation, to increase AAV transduction rates, was diminished when large amounts of vector were used. Absolute neutrophil counts increased 10- to 50-fold for the period of observation to levels that would be therapeutic in the treatment of cyclic neutropenia. In conclusion, gene therapy with AAV vectors synthesizing G-CSF shows promise for the treatment of disorders featuring neutropenia.     

Characterization and functional analysis of granulocyte concentrates collected from donors after repeated G-CSF stimulation

BACKGROUND: Neutropenic patients often develop bacterial or fungal infections not responding to broad-spectrum antibacterial or antifungal agents. Clinical efforts were made with transfusion of granulocyte concentrates; however, functions of granulocytes after multiple G-CSF stimulations and after apheresis are not yet investigated and described sufficiently. STUDY DESIGN AND METHODS: The aim of this study was to characterize functional and immunologic variables of granulocytes in blood samples drawn from donors before and after each stimulation episode with G-CSF, in the resulting granulocyte concentrates and in the patients 8 hours after transfusion. RESULTS: Chemotaxis was not influenced, neither by G-CSF application nor by apheresis. Multiple G-CSF stimulations enhanced oxidative burst and phagocytosis of Escherichia coli in donor granulocytes. These values returned to basal levels in granulocyte concentrates. Expression of granulocytic surface antigens was downregulated after application of G-CSF but returned to normal and in part enhanced values in concentrates. A clinically relevant increase of proinflammatory cytokines could not be detected. Leukotriene B4 production was reduced after the fourth G-CSF stimulation in the donor blood and enhanced in the granulocyte concentrate after apheresis. Results in recipients indicate that changes of granulocyte function noted in concentrates were only transient. CONCLUSION: Stimulation of healthy donors with repeated G-CSF injections and subsequent granulocyte apheresis does not dramatically change decisive functions of granulocytes.     

Combined administration of G-CSF and dexamethasone for the mobilization of granulocytes in normal donors: optimization of dosing

BACKGROUND: The clinical utility of neutrophil (polymorphonuclear leukocyte, PMN) transfusion therapy has been compromised, in part, by the inability to obtain sufficient quantities of functional neutrophils from donors. Mobilization of PMNs in the peripheral blood of normal volunteers has been shown to be superior when G-CSF is administered in conjunction with dexamethasone to that when either agent is administered alone. The current study was conducted to determine the optimal dosages of G-CSF and dexamethasone to be administered to donors in a granulocyte transfusion program. STUDY DESIGN AND METHODS: Five normal subjects were randomly assigned to each of the following single-dose regimens over five consecutive weeks: 1) subcutaneous (SC) G-CSF at 600 microg and oral (PO) dexamethasone at 8 mg; 2) SC G-CSF at 450 microg and PO dexamethasone at 8 mg; 3) SC G-CSF at 450 microg and PO dexamethasone at 12 mg; 4) SC G-CSF at 450 microg; and 5) PO dexamethasone at 12 mg. Venous blood was collected at 0, 6, 12, and 24 hours after drug administration for determination of absolute neutrophil count (ANC). Side effects of drug administration were recorded by using a standardized symptom questionnaire. RESULTS: Maximal ANC was achieved at 12 hours after administration of drugs under each regimen. All four regimens containing G-CSF caused greater than 10-fold increases in the ANC. When administered in conjunction with dexamethasone, G-CSF resulted in statistically similar PMN mobilization at dosages of 450 microg and 600 microg. The combined single-dose regimen of SC G-CSF at 450 microg and PO dexamethasone at 8 mg increased the mean ANC from a baseline value of 2800 per microL to 37,900 per microL at 12 hours after administration. This regimen was well tolerated by the normal volunteers. CONCLUSION: In a single-dose format designed for clinical granulocyte transfusion programs, optimal PMN mobilization can be achieved in normal donors with a combined regimen of SC G-CSF at 450 microg, and PO dexamethasone at 8 microg.     

Granulocyte transfusions from G-CSF-stimulated donors for the treatment of severe infections in neutropenic pediatric patients with onco-hematological diseases

From March 1994 to January 2001, 15 courses of granulocyte transfusion (GTX) were administered to 13 neutropenic patients (6 male and 7 female patients; median age 7 years, range 3 months to 14 years) affected by: acute lymphoblastic leukemia (ALL) in 6 cases, acute myeloid leukemia (AML) in 5, very severe aplastic anemia in 1, and familial erythrophagocytic lymphohistiocytosis (FEL) in 1. Infections were classified as microbiologically defined and clinically defined infections in 8 and 7 episodes, respectively. Before the GTX transfusions, broad-spectrum antibacterial and antifungal therapy had been administered for a median of 12 (range 5-28) and 8 days (range 2-50), respectively, with no improvement. G-CSF was administered prior to GTX in 9 episodes of infection, with a median of 9 days of treatment (range 4-30). Leukapheresis was obtained from 15 related donors (father, 10; mother, 3; sister, 1; aunt, 1) after s.c. stimulation with G-CSF, 300 micro g daily, starting from day -3 (where day 0 was the day of the first granulocyte collection) and continuing throughout the period of GTX treatment. The donors' median white blood cell (WBC) count at leukapheresis was 31.6 x 10(9)/l (range 12-56), and the median yield was 31.39 x 10(9) WBC (range 2.96-64.73 x 10(9)), with a proportion of PMN of 90-95%. Overall, 70 GTX were administered, with a median of 4 GTX per episode of infection (range 2-11). The combination of GTX with antimicrobial therapy led to complete or partial recovery in 6 and in 3 of 15 episodes (60%), respectively. Priming of the donor with G-CSF was well tolerated, the most common side-effects being bone pain, malaise and paresthesia. All donors are alive and well after a median of 4.5 years (range 0.8-7.7) from donation. We conclude that GTX is potentially useful when the severity of the infection and the host's immunodeficiency make any other antimicrobial treatment ineffectual. Long-term safety data on the stimulation of donors with G-CSF have been reassuring to date. Further controlled studies are needed to assess the exact role of GTX in the outcome of neutropenic patients with severe infection and any criteria for patient selection and the timing of GTX administration.     

Austrian Arbeitsgemeinschaft für Gyn?kologische Onkologie (AGO) guideline for prophylaxis with granulocyte colony-stimulating factors (G-CSF) in gynecologic malignancies, including breast cancer

The current knowledge and recommendations on the clinical use of granulocyte colony-stimulating factors (G-CSF) in gynecologic cancers including breast cancer, along with the clinical experience of the members of the working group of the Austrian Arbeitsgemeinschaft für Gyn?kologische Onkologie (AGO), have been summarized. G-CSF is either administered as primary or secondary prophylaxis of febrile neutropenia. The term "primary prophylaxis" denotes the prophylactic use of G-CSF as early as during the first cycle of a new chemotherapeutic regimen. Secondary prophylaxis, on the other hand, defines the use of G-CSF after development of grade 4 neutropenia or febrile neutropenia in a preceding cycle of a particular chemotherapeutic regimen. When chemotherapy regimens are associated with a > 20 % risk of febrile neutropenia such as TAC (docetaxel-doxorubicin-cyclophosphamide), primary prophylaxis with G-CSF is indicated. When chemotherapy regimens are associated with a 10-20 % risk of febrile neutropenia, the decision for primary prophylaxis with G-CSF is based upon patient-related risk factors such as age > 65 years, previous cytotoxic treatment(s) and/or radiation therapy, preexisting tumor-related neutropenia or bone marrow involvement, preexisting neutropenia, infections/open sores, reduced Karnofsky performance status/WHO performance status and reduced nutritional status, advanced malignant disease, history of prior febrile neutropenia, impaired kidney function, and hepatic failure particularly with hyperbilirubinaemia. The patient's individual overall febrile neutropenia risk should be assessed prior to each chemotherapy cycle.     

Comparison of the approaches to non-febrile neutropenia developing in children with acute lymphoblastic leukemia

The objectives of this study was to investigate of the influences of high-dose (20 mg/kg/day) methyl prednisolone (HDMP) and granulocyte colony stimulating factor (G-CSF) in shortening the duration of chemotherapy-induced neutropenia encountered in children with ALL receiving maintenance therapy. Sixty-four non-febrile neutropenic attacks developed in 29 patients with ALL receiving St Jude XIII maintenance protocol were evaluated retrospectively. The patients were clinically followed up without drugs for shortening the duration of neutropenia in 21 (32.8%) attacs, while HDMP and G-CSF were administered in 26 (40.6%) and 17 (26.6%) attacks, respectively. After the detection of neutropenia, restoration of neutrophil counts at 2nd or 4th days to the levels that allow resuming the chemotherapy were considered as success. While second day and overall success rates in patients administered HDMP and G-CSF were significantly higher than the patients who were observed clinically. Both second day and overall neutrophil counts were significantly higher in patients administered G-CSF than the other groups. Methyl prednisolone and G-CSF treatments were well-tolerated by the patients. The cost-per neutropenic attack was significantly higher in G-CSF group than of the HDMP group. Especially in patients experiencing frequent neutropenic attacks and hence interruptions of the therapy, one of the myelopoiesis induction therapies can be used to shorten the duration of neutropenia. For this indication short-course HDMP therapy can be considered as an alternative to G-CSF in this patients due to its relatively low cost, amenability to outpatient administration, and well-tolerability by children.     

Granulocyte colony-stimulating factor administration: adverse events

Recombinant human granulocyte colony-stimulating factor (G-CSF) has been in clinical use for approximately 2 decades. In healthy donors, it has been used to mobilize peripheral blood progenitor cells for hematopoietic stem cell transplantation and granulocytes for apheresis collection. In patients, it has been used to decrease the duration of neutropenia after chemotherapy and to offset the neutropenia due to myelodysplasia, acquired immunodeficiency syndrome, and genetic disorders of granulocyte production. As the number of uses of G-CSF in clinical practice grows, more side effects of this generally safe pharmaceutical agent are being recognized. Our objective in this article is to provide an in-depth review of the reported adverse events associated with the use of G-CSF.     

Recombinant granulocyte colony-stimulating factor (G-CSF) in infectious diseases: still a debate

Granulocyte colony-stimulating factor (G-CSF), a central mediator of the endogenous response to infection and inflammation, is approved for use in the prevention of infection-related complications in patients with nonmyeloid malignancies during antineoplastic therapy associated with high risk of severe neutropenia. Administration of granulocyte colony-stimulating factor results in improvement of host defence paired with anti-inflammatory effects. There is evidence from animal and clinical studies that administration of granulocyte colony-stimulating factor may also be beneficial in non-neutropenic infections. This review focuses mainly on the results of different animal and clinical studies of granulocyte colony stimulating factor used in the treatment of severe infections and sepsis.     

An adult dog with cyclic neutropenia treated by lentivirus- mediated delivery of granulocyte colony-stimulating factor

Cyclic neutropenia occurs in humans and gray collie dogs, is characterized by recurrent neutropenia, and is treated by daily injections of recombinant granulocyte colony-stimulating factor (G-CSF). After showing that canine recombinant G-CSF increased neutrophil counts in an affected dog, we administered intramuscularly 2 x 10(9) infectious units (IU) of a lentiviral vector encoding canine G-CSF cDNA. Elevated, therapeutic neutrophil production was obtained for nearly 18 months. Lentiviral vector treatment provided a mean neutrophil count of 29,230 +/- 12,930 cells/microl, which was significantly increased over both the pretreatment value (5,240 +/- 4,800 cells/microl; p < 0.0001) and the neutrophil count during G-CSF administration (17,820 +/- 11,100 cells/microl; p < 0.0001). By systemic infusion of recombinant G-CSF to normal dogs we estimated that 2 x 10(9) IU of lentivirus delivered 3.5 microg of G-CSF per kilogram per day. After lentiviral vector treatment the gray collie gained weight, showed no clinical signs of infection and fever, and no longer needed housing in a pathogen-free environment. Genomic DNA harvested from muscle at the injection sites was positive for provirus, whereas gonad, lung, spleen, heart, liver, kidney, and noninjected muscle samples were negative. These studies show that an adult animal is responsive long-term to lentivirus-mediated G-CSF delivery, suggesting this approach may be applied for treatment of adult patients with cyclic and other neutropenias.     

Febrile neutropenia, colony-stimulating factors and therapy: time for a new methodology?

The utilization of granulocyte colony-stimulating factors (G-CSF) in febrile neutropenia has been controversial for many years. Berghmann et al.'s meta-analysis again demonstrates that G-CSF does not have an impact on mortality in febrile neutropenia, because the depth and duration of neutropenia in the trials are variable. Also, with mortality from febrile neutropenia less than 15%, any further study would require a vast number of patients to demonstrate a difference in mortality. The Elting and Cantor review provides a new paradigm to studies in patients with febrile neutropenia. These authors recognize that cost, quality of life, life-years gained and adverse events experienced with new therapies should be evaluated, in addition to the standard measures of infection resolution and related mortality. Therefore, for the evaluation of new therapeutic interventions, a consensus on stratified risk factors or the use of an already established model could provide end-points with comparable measurements.     

Granulocyte colony stimulating factor treatment for delayed recovery of ticlopidine-related neutropenia

We describe the case of a patient who developed neutropenia associated with sepsis and endophthalmitis after ticlopidine therapy for coronary stenting. The neutropenia did not resolve until granulocyte colony stimulating factor (G-CSF) was given. This uncommon case brings to attention the need for the immediate use of G-CSF in patients with delayed recovery from drug-related neutropenia and severe infection.     

Clinical application of hematopoietic growth factor (IL-3, G-CSF, GM-CSF, and EPO)]

Hematopoietic growth factors were found as factors stimulating hematopoietic colony formation in in vitro culture system using bone marrow cells as a source of hematopoietic progenitor cells. Erythropoietin, a growth factor stimulating erythroid lineage has now been clinically used as an therapeutic agent for anemia of chronic renal failure. Macrophage colony-stimulating factor (M-CSF), a growth factor stimulating the production of leukocytes including monocytes and neutrophils has been clinically used as an agent for leukopenic patients after anti-cancer therapy. M-CSF improves a survival rate after bone marrow transplantation (BMT) through the reduction of mortality rate associated with BMT such as bleeding, engraftment failure and GVHD. M-CSF accelerated platelet production when injected to thrombopenic patients with solid tumor after anticancer therapy. Granulocyte CSF (G-CSF) is a most powerful agent for various kinds of neutropenia such as neutropenia after anti cancer therapy, neutropenia after BMT, aplastic anemia, chronic neutropenia of children and myelodysplastic syndrome. However, since G-CSF stimulates growth of leukemic cells in vitro, careful observations should be required when clinically used on leukemic patients. Clinical studies of granulocyte-macrophage CSF (GM-CSF) and interleukin 3 (IL-3) are now in progress, in which a promoting activity of leukocyte production of these factors is evaluated.     

Granulocyte transfusions for pediatric patients and the establishment of national treatment guidelines and donor registry

G-CSF/dexamethasone stimulated donor derived granulocyte transfusion (GTX) has been shown in non-randomized studies to be a useful co-therapy in immune-compromised patients unresponsive to conventional antimicrobial treatments. Reports of GTX are however usually single institution adult experiences. Substantiated pediatric data, other than in neonates, is less common.     

Survival among children and adults treated with granulocyte transfusions: Twenty years’ experience at a Brazilian blood center

BackgroundIt remains controversial whether granulocyte transfusions as a supportive treatment improve survival in patients with febrile neutropenia or granulocyte dysfunctions. We describe survival rates subsequent to granulocyte transfusions in pediatric and adults patients treated at a major blood center in Brazil.Material and methodsWe retrospectively reviewed the clinical charts of pediatric and adult patients treated with granulocyte transfusions at our institution from January 2000 to October 2019. We assessed demographic characteristics, clinical features, indications for transfusion, units transfused, dose of granulocytes administered and survival rates 30 and 100 days after the initial transfusion.ResultsWe identified 64 pediatric and 67 adult patients treated with 262 granulocyte transfusions. An optimal dose (> 0.6 × 10⁹ granulocytes per kilogram per transfused unit) was available for transfusion in 80.4 % of pediatric patients but in only 19.6 % of adults (p = 0.017). Thirty days after their first granulocyte transfusion, 38 (59.4 %) pediatric and 61 (91 %) adult patients had died. Patients receiving the optimal dose of granulocytes had better survival outcomes, but even among this sub-group, adults were more likely to die than were children either at 30 days (OR = 8.67, 95 %CI 2.69–34.9) or 100 days (OR = 6.27, 95 %CI 1.86–25.9) after their initial granulocyte transfusion.ConclusionSurvival rates following granulocyte transfusion varied by the dose transfused and were higher in children than in adults.     

Optimizing the management of chemotherapy-induced neutropenia

Chemotherapy-induced neutropenia (CIN), the most common dose-limiting toxicity of cancer chemotherapy, is associated with numerous clinical, personal, and economic consequences. The principal strategies for managing CIN are reducing the dose intensity of the chemotherapy, using antibiotics, and using colony-stimulating factors (CSFs). Reducing or delaying the chemotherapy dose is effective, but this can compromise treatment outcomes. Antibiotics can be lifesaving, but they are associated with numerous adverse effects and the emergence of resistant pathogens. The granulocyte CSF (G-CSF) filgrastim can reduce the incidence, duration, and severity of CIN, as well as the risk of infection, in patients treated with myelosuppressive chemotherapy. The availability of pegfilgrastim, a sustained-duration G-CSF that has benefits comparable to those of filgrastim with a single injection per chemotherapy cycle, has simplified CSF therapy.     

Leukapheresis and granulocyte transfusion.

Granulocyte transfusion is becoming widely used in the treatment of infections in granulocytopenic patients. Several techniques are available for granulocyte collection. Some involve centrifugation of the whole blood and one removes granulocytes from whole blood by reversible adhesion to nylon fibers. The risks to the donor from leukapheresis do not appear to be greater than from whole blood donation. Granulocytes collected by centrifuge techniques function normally in vitro and have normal intravascular recovery and disappearance following transfusion. Granulocytes collected by filtration leukapheresis function almost normally in vitro but have a reduced intravascular recovery and abnormal kinetics as they leave the circulation. The role of leukocyte typing and compatibility testing for granulocyte transfusion is controversial. When the recipient has circulating antibody against donor leukocytes, transfused leukocytes do not circulate or migrate to sites of infection but are sequestered in the liver and spleen. Clinical studies have not defined whether patients benefit equally well clinically from transfusion of compatible or incompatible granulocytes. Initial reports of clinical trials of granulocyte transfusion were promising. However, similar patients who did not receive granulocytes were not studied. Most subsequent controlled trials showed a clear benefit from granulocyte transfusion while others did not. Differences in antibiotic therapy, chemotherapy, use of laminar flow rooms, and grouping of patients make it difficult to compare these clinical trials. Some, but not all, infected granulocytopenic patients benefit from transfusion. Granulocyte transfusions improve survival of granulocytopenic patients with gram negative sepsis and prolonged bone marrow aplasia. Studies are now attempting to identify other patients who should receive granulocytes, the optimum dose and schedule of transfusions, the optimum time to begin transfusion, and the value, if any, of prophylactic transfusions.     

Clinical efficacy of adjunctive G-CSF on solid tumor and lymphoma patients with established febrile neutropenia

Background

The use of granulocyte colony-stimulating factor (G-CSF) as a prophylaxis against febrile neutropenia (FN) is well documented in the literature; however, the therapeutic use of G-CSF in the treatment of FN remains controversial. This study assessed the efficacy of adjunctive G-CSF in the treatment of FN by evaluating clinical outcomes.

Methods

This was a single-center, prospective cohort study conducted at the National Cancer Center in Singapore. Adult patients who had received chemotherapy and developed FN between January 2009 and January 2012 were included in the analysis. The clinical efficacy of adjunctive G-CSF was evaluated by investigating the duration of hospitalization, duration to absolute neutrophil count (ANC) recovery, duration of grade IV neutropenia, duration to fever resolution, duration of antibiotic therapy, and incidence of documented infections. A multivariate analysis was performed to identify patients who could potentially benefit from adjunctive G-CSF.

Results

Four hundred and thirty patients were analyzed. Majority manifested low-risk FN (81.2 %) based on the Multinational Association of Supportive Care in Cancer (MASCC) scoring. Compared to patients who did not receive adjunctive G-CSF, patients receiving adjunctive G-CSF had a nonsignificant reduction in the duration of hospitalization (3.5 vs. 3.7 days, p?=?0.41) and in ANC recovery time (3.4 vs. 3.5 days, p?=?0.76). Neutropenia-related mortality was lower among those who have received adjunctive G-CSF (2.4 vs. 8.4 %, p?=?0.006). Patients of Indian ethnicity and those who underwent gemcitabine-containing chemotherapy were less likely to receive adjunctive G-CSF treatment.

Conclusions

This observational study suggested that adjunctive G-CSF may confer clinical benefits among solid tumor and lymphoma patients with established febrile neutropenia. Further research should be conducted to validate the findings.     

The effects of granulocyte colony-stimulating factor in preclinical models of infection and acute inflammation

The cytokine granulocyte colony-stimulating factor (G-CSF) is a potent endogenous trigger for the release of neutrophils from bone marrow stores and for their activation for enhanced antimicrobial activity. G-CSF has been widely evaluated in preclinical models of acute illness, with generally promising though divergent results. A recombinant G-CSF molecule has recently undergone clinical trials to assess its efficacy as an adjuvant therapy in community-acquired and nosocomial pneumonia, however, these studies failed to provide convincing evidence of benefit. We undertook a systematic review of the published literature reporting the effects of modulation of G-CSF in preclinical in vivo models to determine whether evidence of differential efficacy might explain the disappointing results of human studies and point to disease states that might be more likely to benefit from G-CSF therapy. G-CSF has been evaluated in 86 such studies involving a variety of different models. The strongest evidence of benefit was seen in studies involving intraperitoneal challenge with live organisms; benefit was evident whether the agent was given before or after challenge. G-CSF demonstrates anti-inflammatory activity in models of systemic challenge with viable organisms or endotoxin, but only when the agent is given before challenge; evidence of benefit after challenge was minimal. Preclinical models of intrapulmonary challenge only show efficacy when the cytokine is administered before the infectious challenge, and suggested harm in gram-negative pneumonia resulting from challenge with Escherichia coli or Klebsiella. There is little evidence for therapeutic efficacy in noninfectious models of acute illness. We conclude that the most promising populations for evaluation of G-CSF are neutropenic patients with invasive infection and patients with intra-abdominal infection, particularly those with the syndrome of tertiary, or recurrent, peritonitis. Significant variability in the design and reporting of studies of preclinical models of acute illness precludes more sophisticated data synthesis.     

G-CSF rescues the memory impairment of animal models of Alzheimer's disease

Most of the current clinical treatments for Alzheimer's disease (AD) are largely symptomatic and can have serious side effects. We have tested the feasibility of using the granulocyte colony-stimulating factor (G-CSF), which is known to mobilize hematopoietic stem cells (HSCs) from the bone marrow into the peripheral blood, as a therapeutic agent for AD. Subcutaneous administration of G-CSF into two different beta-amyloid (Abeta)-induced AD mouse models substantially rescued their cognitive/memory functions. The rescue was accompanied by the accumulation of 5-bromo-2'deoxyuridine-positive HSCs, as well as local neurogenesis surrounding the Abeta aggregates. Furthermore, the level of acetylcholine in the brains of Tg2576 mice was considerably enhanced upon G-CSF treatment. We suggest that G-CSF, a drug already extensively used for treating chemotherapy-induced neutropenia, should be pursued as a novel, noninvasive therapeutic agent for the treatment of AD.