Exacerbation by granulocyte colony-stimulating factor of prior acute lung injury: implication of neutrophils

OBJECTIVE: Granulocyte colony-stimulating factor is widely prescribed to hasten recovery from cancer chemotherapy-induced neutropenia and has been reported to induce pulmonary toxicity. However, circumstances and mechanisms of this toxicity remain poorly known. DESIGN: To reproduce a routine situation in cancer patients receiving chemotherapy, we investigated the mechanisms underlying granulocyte colony-stimulating factor-induced exacerbation of alpha-naphthylthiourea-related pulmonary edema. SETTING: Laboratory research unit. SUBJECTS: Male specific-pathogen-free Sprague-Dawley rats. INTERVENTIONS: The effects of granulocyte colony-stimulating factor given alone or after alpha-naphthylthiourea used to induce acute lung injury were investigated. MEASUREMENTS AND MAIN RESULTS: Lung injury was assessed based on neutrophil sequestration (myeloperoxidase activity in lung tissue) and influx into alveolar spaces (bronchoalveolar lavage fluid cell quantification) and on edema formation (wet/dry lung weight ratio) and alveolar protein concentration into bronchoalveolar lavage fluid. Tumor necrosis factor-alpha and interleukin-1beta were measured in serum, lung homogenates, and isolated alveolar macrophage supernatants. In control rats, granulocyte colony-stimulating factor (25 microg/kg) significantly elevated circulating neutrophil counts without producing alveolar recruitment or pulmonary edema. alpha-Naphthylthiourea significantly increased the wet/dry lung weight ratio (4.68 +/- 0.04 vs. 4.38 +/- 0.07 in controls, p=.04) and induced alveolar protein leakage. Adding granulocyte colony-stimulating factor to alpha-naphthylthiourea exacerbated pulmonary edema, causing neutrophil sequestration in pulmonary vessels, significantly increasing lung myeloperoxidase activity (12.7 +/- 2.0 mOD/min/g vs. 1.1 +/- 0.4 mOD/min/g with alpha-naphthylthiourea alone; p<.0001), and increasing proinflammatory cytokine secretion. alpha-Naphthylthiourea-related pulmonary edema was not exacerbated by granulocyte colony-stimulating factor during cyclophosphamide-induced neutropenia or after lidocaine, which antagonizes neutrophil adhesion to endothelial cells. Tumor necrosis factor-alpha and interleukin-1beta concentrations in alveolar macrophage supernatants and lung homogenates were significantly higher with alpha-naphthylthiourea + granulocyte colony-stimulating factor than with either agent alone, and anti-tumor necrosis factor-alpha antibodies abolished granulocyte colony-stimulating factor-related exacerbation of alpha-naphthylthiourea-induced pulmonary edema. In rats with cyclophosphamide-induced neutropenia, tumor necrosis factor-alpha concentrations in alveolar macrophage supernatants and lung homogenates were significantly decreased compared with rats without neutropenia. CONCLUSION: Granulocyte colony-stimulating factor-related pulmonary toxicity may involve migration of neutrophils to vascular spaces, adhesion of neutrophils to previously injured endothelial cells, and potentiation of proinflammatory cytokine expression.     

Deterioration of previous acute lung injury during neutropenia recovery

DESIGN: Although neutropenia recovery is associated with a high risk of deterioration of respiratory condition, no studies designed to identify risk factors for acute respiratory distress syndrome (ARDS) in this situation have been published. SETTING: Medical ICU in a French teaching hospital. SUBJECTS: We conducted a study to describe critically ill cancer patients with ARDS during neutropenia recovery (defined as the 7-day period centered on the day the neutrophil count rose above 1000/mm3 [day 0]) and to compare them with critically ill cancer patients without ARDS during neutropenia recovery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: During a 10-yr period, 62 critically ill cancer patients recovered from neutropenia, of whom 21 experienced ARDS during neutropenia recovery, with a median time of -1 days (-2.5-1) between day 0 and ARDS. In-ICU mortality in these 21 patients was 61.9%. As compared with non-ARDS patients, ARDS patients were less likely to have myeloma and more likely to have leukemia/lymphoma treated with adriamycin, a history of pneumonia before neutropenia, and a neutropenia duration >10 days; they had a shorter time since malignancy diagnosis and a longer time from chemotherapy to neutropenia. Neither the leukocyte counts on day 0 nor those during the 6-day neutropenia recovery period were predictive of ARDS. CONCLUSIONS: Patients with acute respiratory failure after prolonged neutropenia complicated by pneumonia are at increased risk for ARDS.     

Effect of granulocyte colony-stimulating factor on bleomycin-induced acute lung injury and pulmonary fibrosis

OBJECTIVE: Potentially fatal pulmonary toxicity is a dreaded complication of bleomycin. Increased use of granulocyte colony-stimulating factor in patients receiving chemotherapy has been paralleled by an increased incidence of bleomycin-induced pulmonary toxicity. We investigated whether granulocyte colony-stimulating factor (25 microg x kg(-1) x day(-1), 4 days) enhanced endotracheal bleomycin-induced (5 mg/kg) acute lung injury and fibrosis in rats. SETTING: University laboratory. SUBJECTS: Sprague-Dawley rats. INTERVENTIONS: We compared the effects of alveolar instillation of bleomycin in rats treated with either granulocyte colony-stimulating factor or saline. MEASUREMENTS AND MAIN RESULTS: Mortality was 25% with bleomycin only and 50% with bleomycin + granulocyte colony-stimulating factor. Granulocyte colony-stimulating factor increased alveolar neutrophil recruitment, pulmonary edema, and lung myeloperoxidase activity on day 4. Lung static compliance on day 15 was severely decreased with bleomycin alone and showed a further significant decrease when granulocyte colony-stimulating factor was added (controls, 3.85 +/- 0.14 mL/kPa; bleomycin, 1.44 +/- 0.06 mL/kPa; and bleomycin + granulocyte colony-stimulating factor, 0.65 +/- 0.09 mL/kPa; control vs. bleomycin, p <.0001; and bleomycin vs. bleomycin + granulocyte colony-stimulating factor, p =.0003). Lung morphology with bleomycin + granulocyte colony-stimulating factor showed, in addition to the changes observed with bleomycin alone, four patterns indicating more severe disease: honeycomb foci, pleural thickening with hyaline fibrosis, interstitial granuloma with increased number of macrophages but not neutrophils, and established interstitial fibrosis. Lidocaine, which prevents neutrophil adhesion to endothelial cells, inhibited granulocyte colony-stimulating factor-related exacerbation of acute lung injury (bronchoalveolar lavage fluid cells and pulmonary edema) and pulmonary fibrosis (lung static compliance and morphologic changes). CONCLUSIONS: Granulocyte colony-stimulating factor enhances bleomycin-induced lung toxicity by a mechanism that probably involves neutrophils.     

Severe congenital neutropenia: clinical effects and neutrophil function during treatment with granulocyte colony-stimulating factor.

We studied neutrophil function and clinical responses in seven patients with severe congenital neutropenia (SCN) after they received treatment with recombinant human granulocyte colony stimulating factor (rhG-CSF). Two subpopulations of patients with SCN were defined by their pattern of absolute neutrophil response, superoxide production, and cytochrome b559 levels. One group had an oscillating absolute neutrophil count and reduced ability to produce superoxide and cytochrome b559 (n = 4), and the second group had a relatively constant absolute neutrophil count response with normal superoxide and cytochrome levels (n = 3). Neutrophils from both groups had decreased surface expression of FcRIII and abnormal upregulation of the C3bi receptor (CR3). All patient neutrophils, however, had normal contents of the primary granule constituent, beta-glucuronidase, and the specific granule constituent, vitamin B 12 binding protein. The clinical response to rhG-CSF was evident by marked improvement in the degree of periodontitis and reduction in the number of oral ulcers in both groups of patients. Although neutrophil function is not completely normal in patients with SCN, it is likely that enough redundancy exists in neutrophil bactericidal capacity to promote normal host response to inflammation.     

Modulation of neutrophil apoptosis by granulocyte colony-stimulating factor and granulocyte/macrophage colony-stimulating factor during the course of acute respiratory distress syndrome

OBJECTIVE: To determine whether bronchoalveolar lavage fluid (BALF) from patients either at risk for the acute respiratory distress syndrome (ARDS) or with sustained ARDS modulates neutrophil apoptosis; to measure the BALF concentrations of the apoptosis inhibitors granulocyte colony-stimulating factor (G-CSF) and granulocyte/macrophage colony-stimulating factor (GM-CSF) before and after the onset of ARDS; and to determine whether the BALF concentrations of G-CSF and/or GM-CSF are associated with clinical outcome. DESIGN: Prospective cohort study. SETTING: Tertiary university hospital. PATIENTS: Twenty patients at risk for ARDS and 45 patients with established ARDS. INTERVENTIONS: Patients at risk for ARDS underwent bronchoalveolar lavage within 24 hrs of being identified, then again 72 hrs later. Patients with ARDS underwent bronchoalveolar lavage within 24 hrs of meeting ARDS criteria, then again on days 3, 7, and 14 of the disease. MEASUREMENTS AND MAIN RESULTS: Normal peripheral blood neutrophil were incubated overnight in BALF from normal volunteers, from patients at risk for ARDS, or from patients with ARDS. neutrophil apoptosis was determined by flow cytometric analysis of annexin V binding. G-CSF and GM-CSF were measured in BALF by immunoassays. Compared with normal BALF, BALF from patients on days 1 and 3 of ARDS inhibited neutrophil apoptosis, but BALF from patients at later stages of ARDS, or from patients at risk for ARDS, did not. The BALF concentrations of both G-CSF and GM-CSF were elevated early in ARDS and decreased toward later stages. Patients who lived had significantly higher concentrations of GM-CSF in the BALF than those who died. CONCLUSIONS: We conclude that the antiapoptotic effect of ARDS BALF on normal neutrophil is highest during early ARDS, and decreases during late ARDS. G-CSF and GM-CSF are present in BALF from patients with ARDS, and their concentrations parallel the antiapoptotic effect of ARDS BALF. These data support the concept that the life-span of neutrophil in the air spaces is modulated during acute inflammation. GM-CSF in the air spaces is associated with improved survival in patients with ARDS.     

急性肺损伤炎性细胞凋亡异常及粒细胞集落刺激因子调控的研究

目的 探讨急性肺损伤时支气管肺泡灌洗液(BALF)中的中性粒细胞(PMN)凋亡发生规律及其与粒细胞集落刺激因子调控关系.方法 豚鼠30只,分为3组:组1为生理盐水正常对照组,组2为油酸致病组,组3为油酸+粒细胞集落刺激因子组.组2、组3分别由尾静脉注射油酸(0.12 ml/kg)造成豚鼠急性肺损伤模型.组1则注入生理盐水.组3在实验造模前2 d由皮下注射粒细胞集落刺激因子1.0μg/kg,1次/d.组1、组2、组3分别于注射后2 h用生理盐水进行全肺支气管肺灌洗,收集BALF.用梯度密度法离心收集PMN.用原位末端标记法检测BALF中PMN凋亡.结果 组2、组3和组1BALF中PMN凋亡百分比分别为(2.500±1.080)%、(3.500±0.850)%、(6.400±1.505)%.组2、组3较组1 BALF中PMN凋亡均显著降低(均P＜0.01).结论 急性肺损伤炎性细胞PMN凋亡延迟,PMN持续激活和释放毒性内容物与肺损伤有密切关系.粒细胞集落刺激因子能调控干预急性肺损伤时PMN凋亡延迟.     

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.     

Increased granulocyte colony-stimulating factor responsiveness but normal resting granulopoiesis in mice carrying a targeted granulocyte colony-stimulating factor receptor mutation derived from a patient with severe congenital neutropenia.

The role of mutations of the granulocyte colony-stimulating factor receptor (G-CSFR) in the pathogenesis of severe congenital neutropenia (SCN) and the subsequent development of acute myeloid leukemia (AML) is controversial. Mice carrying a targeted mutation of their G-CSFR that reproduces the mutation found in a patient with SCN and AML have been generated. The mutant G-CSFR allele is expressed in a myeloid-specific fashion at levels comparable to the wild-type allele. Mice heterozygous or homozygous for this mutation have normal levels of circulating neutrophils and no evidence for a block in myeloid maturation, indicating that resting granulopoiesis is normal. However, in response to G-CSF treatment, these mice demonstrate a significantly greater fold increase in the level of circulating neutrophils. This effect appears to be due to increased neutrophil production as the absolute number of G-CSF-responsive progenitors in the bone marrow and their proliferation in response to G-CSF is increased. Furthermore, the in vitro survival and G-CSF-dependent suppression of apoptosis of mutant neutrophils are normal. Despite this evidence for a hyperproliferative response to G-CSF, no cases of AML have been detected to date. These data demonstrate that the G-CSFR mutation found in patients with SCN is not sufficient to induce an SCN phenotype or AML in mice.     

粒细胞集落刺激因子与干细胞因子合用对急性心肌梗死模型大鼠心功能的影响

背景:骨髓干细胞动员以其无创伤、无免疫排斥反应,不需要干细胞提取、培养、扩增等工作倍受青睐。目的:观察联合应用粒细胞集落刺激因子和干细胞因子对大鼠急性心肌梗死的治疗作用。设计:随机对照观察。单位:锦州医学院药理教研室实验室。材料:选用32只成年雄性SD大鼠,体质量(200±20)g,购自锦州医学院实验动物中心。重组人粒细胞集落刺激因子(北京双鹭制药),重组人干细胞因子(成都地奥有限公司)。方法:实验于2005-07/11在锦州医学院药理教研室实验室进行。①5mg/kg盐酸异丙基肾上腺素左下腹腔注射复制急性心肌梗死模型,3h后将大鼠随机分为4组,每组8只。综合治疗组:用生理盐水稀释浓度至10mg/L的重组人粒细胞集落刺激因子1mL/kg和重组人干细胞因子1mL/kg皮下注射,连续5d。粒细胞集落刺激因子组:单用生理盐水稀释浓度至10mg/L的rhG-CSF1mL/kg皮下注射,每只大鼠和综合治疗组大鼠注射药品差量用生理盐水(1mL/kg)补足,连续5d。干细胞因子组:单用生理盐水稀释浓度至10mg/L的人干细胞因子1mL/kg皮下注射,每只大鼠和综合治疗组大鼠注射药品差量用生理盐水(1mL/kg)补足,连续5d。对照组:单用生理盐水(2mL/kg)皮下注射。②分别于造模后第14d和28d,摸球法从每组大鼠中抽取4只麻醉,自左心室心尖部插入内充肝素钠的塑料管至左心腔,用Medlab-u18c生物信号采集处理系统描记左心室峰压,左心室舒张末压,左室内压最大上升/下降速度,并同步记录心率。拔出气管插管,立即剪掉心脏,剪掉心房及右心室,微量天平称重,计算左心室质量/体质量,评估心肌重塑情况,将组织块切片,光镜下观测大鼠心肌病理形态及梗死面积。采用细胞图像分析仪病理图文分析每组大鼠心肌梗死面积。主要观察指标:各组大鼠左心功能指标、心肌梗死面积、心率和心室重塑情况及大鼠心肌病理形态。结果:纳入大鼠32只全部进入结果分析,无脱落。①大鼠左心功能指标比较结果:综合治疗组大鼠造模14,28d后左心室收缩压、左心室舒张末压、左心室内压最大上升/下降速度高于其他3组,造模28d时上述各指标均高于14d,差异有统计学意义(P<0.05),粒细胞集落刺激因子组两时间点上述指标均大于干细胞因子组及对照组(P<0.05)。②大鼠两时间点心肌梗死面积、心率和心室重塑情况:综合治疗组大鼠造模14,28d后心肌梗死面积及左心室重量小于其他3组,造模后28d心肌梗死面积小于14d(P<0.05),粒细胞集落刺激因子组两时间点上述指标均小于干细胞因子组与对照组。③大鼠心肌病理形态改变:造模后14及28d,综合治疗组和粒细胞集落刺激因子组均未见明显心肌瘢痕组织,有新生毛细血管生长,粒细胞集落刺激因子组毛细血管密度小于综合治疗组,均有成纤维细胞浸润。干细胞因子组和对照组可见瘢痕组织呈散在的灶性分布,有成堆或散在分布的淋巴细胞,其核小、深染、胞浆少,细胞间胞浆融合,新生肉芽组织增生不明显。结论:粒细胞集落刺激因子和干细胞因子合用对急性心肌梗死大鼠缺血损伤心肌的保护和再生作用优于单用,可改善急性心肌梗死大鼠的心室功能。     

Effect of tyrosine kinase inhibitors,imatinib and nilotinib,in murine lipopolysaccharide-induced acute lung injury during neutropenia recovery

Introduction

Neutrophil recovery has been implicated in deterioration of oxygenation and exacerbation of preexisting acute lung injury (ALI). The aim of this study was to investigate whether imatinib or nilotinib was effective on lipopolysaccharide (LPS)-induced ALI during neutropenia recovery in mice.

Methods

Mice were rendered neutropenic with cyclophosphamide prior to the intratracheal instillation of LPS. Imatinib or nilotinib was administrated by oral gavage during neutropenia recovery. In order to study the effects of drugs, mice were killed on day 5 and blood, bronchoalveolar lavage (BAL) fluid and lung tissue samples were obtained. The lung wet/dry weight ratio and protein levels in the BAL fluid or lung tissue were determined.

Results

Treatment with imatinib or nilotinib significantly attenuated the LPS-induced pulmonary edema, and this result was supported by the histopathological examination. The concentrations of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and myeloperoxidase in BAL fluid were significantly inhibited by imatinib or nilotinib in mice of ALI during neutropenia recovery. The mRNA expressions of platelet-derived growth factor receptor-β and c-KIT in imatinib or nilotinib group were significantly lower than LPS group.

Conclusions

Our data indicated that imatinib or nilotinib effectively attenuated LPS-induced ALI during neutropenia recovery. These results provide evidence for the therapeutic potential of imatinib and nilotinib in ALI during neutropenia recovery.     

Chronic neutropenia. A new canine model induced by human granulocyte colony-stimulating factor.

Normal dogs were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) at 10 micrograms/kg/day for 30 d, which caused an initial neutrophilia, followed by a prolonged period of chronic neutropenia. A control dog treated with recombinant canine G-CSF (rcG-CSF) showed persistent neutrophilia over 3 mo. Serum from dogs during neutropenia contained an antibody to rhG-CSF, which neutralized the stimulatory effects of both rhG-CSF and rcG-CSF on dog marrow neutrophilic progenitor cell growth and on NFS-60 cell proliferation. 4 mo after discontinuation of rhG-CSF, the dogs' neutrophil counts returned to the normal range. Rechallenge with the rhG-CSF re-induced severe neutropenia in 1 wk. Neutropenia was transferred by plasma infusion from a neutropenic dog to a previously normal dog. These data suggest that human rhG-CSF immunizes normal dogs and thereby induces neutralization of endogenous canine G-CSF and neutropenia. This model system should allow more precise definition of the in vivo role of G-CSF.     

Monocyte deactivation in neutropenic acute respiratory distress syndrome patients treated with granulocyte colony-stimulating factor

Introduction

In severely neutropenic septic acute respiratory distress syndrome (ARDS) patients, macrophages and monocytes are the last potentially remaining innate immune cells. We have previously shown, however, a deactivation of the alveolar macrophage in neutropenic septic ARDS patients. In the present study, we tried to characterize in vitro monocyte baseline cytokine production and responsiveness to lipopolysaccharide exposure.

Methods

Twenty-two consecutive patients with cancer were prospectively enrolled into a prospective observational study in an intensive care unit. All patients developed septic ARDS and were divided into two groups: neutropenic patients (n = 12) and non-neutropenic patients (n = 10). All of the neutropenic patients received granulocyte colony-stimulating factor whereas no patient in the non-neutropenic group received granulocyte colony-stimulating factor. We compared monocytes from neutropenic patients with septic ARDS with monocytes from non-neutropenic patients and healthy control individuals (n = 10). Peripheral blood monocytes were cultured, and cytokine levels (TNFα, IL-1β, IL-6, IL-10, and IL-1 receptor antagonist) were assayed with and without lipopolysaccharide stimulation.

Results

TNFα, IL-6, IL-10 and IL-1 receptor antagonist levels in unstimulated monocytes were lower in neutropenic patients compared with non-neutropenic patients. Values obtained in the healthy individuals were low as expected, comparable with neutropenic patients. In lipopolysaccharide-stimulated monocytes, both inflammatory and anti-inflammatory cytokine production were significantly lower in neutropenic patients compared with non-neutropenic patients and control individuals.

Conclusion

Consistent with previous results concerning alveolar macrophage deactivation, we observed a systemic deactivation of monocytes in septic neutropenic ARDS. This deactivation participates in the overall immunodeficiency and could be linked to sepsis, chemotherapy and/or the use of granulocyte colony-stimulating factor.     

Detection of the granulocyte colony-stimulating factor receptor using biotinylated granulocyte colony-stimulating factor: presence of granulocyte colony-stimulating factor receptor on CD34-positive hematopoietic progenitor cells

Granulocyte colony-stimulating factor (G-CSF) was linked to NHS-biotin to yield biotinylated G-CSF (b-G-CSF), which retained the ability to stimulate colony formation by normal bone marrow (BM) cells in methylcellulose. The use of streptivadin-phycoerythrin conjugate in conjunction with flow cytometry demonstrated that the binding of biotnylated G-CSF to its receptor is saturable, competitive, and specific. A 100-fold molar excess of unlabeled G-CSF almost completely inhibited the binding of the biotinylated G-CSF to the human leukemia cell line U937, which is known to posses the G-CSF receptor. G-CSF receptors were clearly detected by flow cytometry on adult human peripheral granulocytes and monocytes, but not on lymphocytes. Using this method, the expression of G-CSF receptors on hematopoietic progenitor cells in bone marrow and umbilical cord blood, detected as CD34-positive (CD34⁺) cells, were examined. A small but significant number of CD34⁺ cells were detected among the bone marrow mononuclear cells and umbilical-cord-blood mononuclear cells (4.28%±0.31%, 1.09%±0.20%, respectively). The percentage of CD34⁺ BM mononuclear cells was significantly higher than for cord blood mononuclear cells (P<0.01). These CD34⁺ cells were then analyzed by biotinylated G-CSF binding. CD34⁺ cells from bone marrow contained 25.8%±7.9% G-CSF receptor positive cells and those from cord blood possessed 29.2% ±7.0% of G-CSF receptor-positive cells. The difference was not statistically significant.     

Antioxidant enzymes are induced during recovery from acute lung injury

OBJECTIVE: To determine the contribution of the pulmonary antioxidant defense enzymes of the hexose monophosphate (HMP) shunt and glutathione systems to recovery from oxidant-mediated lung injury in an animal model shown to closely resemble the clinical syndrome of acute respiratory distress syndrome. DESIGN: Prospective, controlled laboratory study on phorbol myristate acetate (PMA)-induced lung injury in rabbits. SETTING: Animal research laboratory. SUBJECTS: Rabbits were injected with PMA (80 microg/kg) for 3 consecutive days. Control animals received normal saline. MEASUREMENTS AND MAIN RESULTS: Lungs were harvested at 24, 48, 72, and 96 hrs (n = 5/time point) after PMA injection or after the third injection of normal saline in control animals (n = 6). The cytosolic fraction from lung and bronchial alveolar lavage (BAL) fluid was used for measurements of HMP shunt and glutathione enzymes. Pulmonary activity peaked at 48 hrs post-PMA injury with a 40% increase in glucose-6-phosphate dehydrogenase activity and a 32% increase in 6-phosphogluconate dehydrogenase activity over control levels. BAL activity was maximal at 72 hrs with an increase of 98% in glucose-6-phosphate dehydrogenase and 346% in 6-phosphogluconate dehydrogenase activities. Glutathione peroxidase was maximally induced by 77% at 48 hrs in BAL and by 107% at 24 hrs in lung. Glutathione reductase activity did not increase significantly in either lung or BAL. CONCLUSIONS: The observed induction of the antioxidant enzymes in response to PMA suggests that both the HMP shunt and the glutathione systems contribute to the recovery phase of oxidant-mediated lung injury. The inability of natural host defenses to regenerate reduced glutathione may explain failure of recovery from acute respiratory distress syndrome and suggests an avenue for clinical intervention.     

大鼠重症急性胰腺炎时急性肺损伤的实验研究

目的　研究内毒素 (endotoxin ,ET)、细胞因子 (cytokine,CK)、氧自由基 (oxygenfreeradi cals ,OFR)等在重症急性胰腺炎 (severeacutepancreatitis,SAP)时急性肺损伤 (acutelunginjury ,ALI)发病机制中的作用。方法　采用胰管逆行注射 1 5 %去氧胆酸钠制成大鼠重症急性胰腺炎时ALI模型。选用纯雄性健康Wistar大鼠共 4 0只 ,体重 2 2 0～ 2 5 0g,随机分成两组 :假手术对照组 (Sham ,n =10 ) ;SAP模型组(SAP ,n =30 ) ,分别于造模后 2 4h活杀。测定动脉血气 ,血清淀粉酶的含量 ,血清内毒素及血清和肺组织匀浆中的TNF α、IL 6、MDA、SOD的含量 ,肺湿 /干系数以及肺组织病理学改变。结果　SAP组血清内毒素 ,血淀粉酶 ,血清及肺组织匀浆中TNF α、IL 6、OFR均较Sham组明显升高 (P <0 0 1) ;动脉血气显示肺损伤严重 ,肺湿 /干比值较Sham组明显升高 ,肺通透性明显升高 ,肺病理学形态改变加重。结论　ET、TNF、IL 6、OFR在SAP时ALI发生发展中起了重要作用     

粒细胞集落刺激因子受体在急性白血病中的表达及临床意义

目的探讨粒细胞集落刺激因子受体(GCSFR)在急性白血病(AL)中的表达及临床意义。方法选初诊或难治复发的急性髓性白血病(AML)患者30例,急性淋巴细胞白血病(ALL)患者20例,正常对照20例。化疗前留取骨髓5ml,用GCSFR、CD34单抗,采用流式细胞技术(FCM)检测GCSFR、CD34在AL细胞的表达情况。同时制备骨髓单个核细胞(MNC)悬液,并分别加入不同浓度的GCSF(5、10、15、20和25ng/ml),培养24h后用FCM检测其DNA倍体的量。结果GCSFR、CD34的表达率:AML为(76.5±12.8)%和(45.15±4.22)%;ALL为(6.12±1.98)%和(46.75±3.15)%;对照组为(80.5±10.8)%和(3.15±0.22)%。骨髓MNC培养24h后DNA倍体量在AML随着GCSF浓度的增加有上升的趋势,在ALL和对照组无明显变化。结论GCSFR主要表达于AML细胞,并促进其增殖;不表达于ALL细胞,不促进其增殖;也表达于成熟粒细胞,但不促进其增殖。     

不同剂量重组人粒细胞集落刺激因子对大鼠脑缺血再灌注损伤的保护作用

目的探讨重组人粒细胞集落刺激因子(rh G-CSF)对大鼠脑缺血再灌注损伤的神经保护机制并揭示其量效关系。方法 60只雄性SD大鼠随机分为假手术组、模型组、rh G-CSF低、中、高剂量组,采用longa线栓法制作大鼠脑缺血再灌注模型,治疗组于大鼠脑缺血2 h再灌注即刻及24 h分别腹部皮下注射rh G-CSF 25μg/kg、50μg/kg及100μg/kg,假手术组与模型组给予等量生理盐水。术后24 h采用longa及Berderson标准评分法行神经功能评分,2,3,5-氯化三苯基四氮唑(TTC)染色法测定脑梗死体积,免疫组化法(SABC)检测大鼠脑组织中Caveolin-1、COX-2的表达情况,HE染色观察脑组织形态并在高倍镜下计算涂片中炎症细胞数反映脑组织炎症反应。结果 (1)模型组可见明显的神经功能缺损、脑梗死灶及炎症细胞浸润;与模型组相比,rh G-CSF中、高剂量组神经功能评分、炎症细胞数明显减少,梗死体积明显减小(P<0.01);rh G-CSF低剂量组与模型组比较无统计学意义(P>0.05)。(2)与假手术组相比,模型组Caveolin-1、COX-2表达明显增加;与模型组比较,rh G-CSF中、高剂量组Caveolin-1明显升高,COX-2明显降低(P<0.01),低剂量组Caveolin-1及COX-2表达无统计学意义(P>0.05)。中高剂量组之间在神经功能缺损、梗死体积、炎症细胞数、Caveolin-1、COX-2表达方面比较,差异均无统计学意义(P>0.05)。结论 rh G-CSF可能通过升高Caveolin-1,进而降低COX-2表达,对脑缺血再灌注损伤产生神经保护作用,中剂量50μg/kg可能为最佳应用剂量。     

痰热清注射液对急性肺损伤大鼠肺内炎症因子的影响

目的 研究痰热清注射液对内毒素性急性肺损伤(ALI)大鼠肺内炎症因子的影响。方法 清洁级健康SD雄性大鼠56只,随机（随机数字法）分为空白组、模型组、干预组。模型组、干预组分别给予内毒素(LPS)尾静脉注射,1h后,干预组给予痰热清注射液尾静脉注射。三组分别选取2,4,6h三个观察点,取支气管肺泡灌洗液(BALF)放射免疫法检测TNF-α,IL-1β,IL-8的含量及Wright-Giermsa染色计中性粒细胞的比例(ωPMN),并观察肺组织病理学变化及测湿干质量比值(W/D)。采用SPSS 17.0统计软件,以P＜0.05为差异具有统计学意义。结果2,4,6h三个观察点,模型组BALF中TNF-α,IL-1β,IL-8的含量及ωPMN较空白组明显升高(P＜0.05或P＜0.01),肺组织W/D明显增加(P＜0.01),且病理损伤程度明显重于空白组。干预组BALF中TNF-α,IL-1β,IL-8的含量及ωPMN较模型组明显降低(P＜0.05或P＜0.01),肺组织W/D明显减少(P＜0.01)且病理损伤程度明显轻于模型组。结论 痰热清注射液能抑制内毒素性急性肺损伤肺内炎症因子水平,减轻急性肺损伤程度。     

核因子-κB在小鼠急性肺损伤中的作用

目的　探讨核因子 (NF) κB在内毒素 (LPS)诱导的急性肺损伤小鼠发病中的作用。方法　腹腔内注射LPS诱导小鼠急性肺损伤模型。LPS注射后 0、 1、 3、 6、 12测定肺湿重 /干重比值 (W/D) ,迁移率改变电泳法检测肺组织NF κB活性 ,同时酶联免疫吸附法测定肺组织匀浆中肿瘤坏死因子 (TNF) α、白介素 (IL) 10浓度 ,RT PCR检测mRNA表达。结果　LPS注射后 ,W/D比值明显增高 ,6h升高最明显 (4 82± 0 10 ) ,显著高于LPS注射前 (3 6 7± 1 0 4 ,P <0 0 5 )。LPS注射后肺组织核蛋白NF κB活性明显增强 ,6h达到峰值 (40 5 7± 6 2 4 ) ,显著高于LPS注射前 (44 8± 30 9,P <0 0 5 )。肺组织匀浆TNF α和IL 10浓度分别在LPS注射后 6h和 12h升高最明显 ,分别为 (197 1± 5 2 4 )pg/ml和 (6 4 9± 39 7)pg/ml,显著高于LPS注射前 [分别为 (6 1 2± 10 7)pg/ml和 (71 6± 15 9)pg/ml]。与LPS注射前比较 ,LPS注射后 3～ 12h ,肺组织匀浆TNF α和IL 10mRNA表达显著增高。肺组织病理显示肺泡出血、水肿、大量炎症细胞浸润 ,电镜下见Ⅰ型肺泡上皮细胞断裂 ,Ⅱ型肺泡上皮细胞变性。结论　LPS导致肺组织NF κB的活化 ,介导炎症介质大量表达 ,参与急性肺损伤发生     

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.