Cognosco, AnexaFVC, Morrinsville, 3300, New Zealand.
Ontario Veterinary College, University of Guelph, Guelph, ON, Canada N1G 2W1.
J Dairy Sci. 2017 Sep;100(9):7478-7492. doi: 10.3168/jds.2017-12786. Epub 2017 Jun 21.
Treatment with granulocyte colony-stimulating factor (G-CSF) increases polymorphonuclear cell (neutrophil) count and enhances neutrophil function in the periparturient cow. Prepartum undernutrition was hypothesized to reduce the effect of a commercially available recombinant bovine G-CSF product (pegbovigrastim) on neutrophil count and function. Hence this study was undertaken to test the effect of undernutrition for approximately 1 mo before calving on the innate immune response to pegbovigrastim. Cows (n = 99) on pasture were blocked by expected calving date and body condition score and randomly assigned in a 2 × 2 factorial design. The first factor was that cows were fed to exceed energy requirements prepartum (full feeding) or restricted to approximately 85% of prepartum energy requirements (restricted feeding). The second factor was that at approximately 7 d before expected calving date, half the cows in each feed group were injected with pegbovigrastim and the remaining half were injected with saline. Treatments were repeated on the day of calving. Blood samples were collected pre- and postcalving for complete blood count, biochemistry, and in vitro assessment of neutrophil function including phagocytosis, myeloperoxidase release, and oxidative burst. Prepartum energy restriction resulted in lower body weight, a higher proportion of cows with elevated concentrations (i.e., >0.4 mmol/L) of fatty acids, and higher average β-hydroxybutyrate concentrations before calving relative to fully fed cows. Treatment with pegbovigrastim increased the total white cell, neutrophil, lymphocyte, and monocyte counts. Pegbovigrastim treatment resulted in increased release of myeloperoxidase by neutrophils. Prepartum feeding group did not have an effect, and no feeding group × treatment interaction was observed for any of the white cell counts or functional tests. We concluded that pegbovigrastim treatment results in significant increases in neutrophil count and enhances neutrophil function as indicated by increased myeloperoxidase release. The response to pegbovigrastim was not affected by restricted prepartum energy intake.
粒细胞集落刺激因子（G-CSF）治疗可增加围产期牛的多形核细胞（中性粒细胞）计数并增强其功能。据推测，产前营养不良会降低市售重组牛 G-CSF 产品（聚乙二醇化牛粒细胞集落刺激因子）对中性粒细胞计数和功能的影响。因此，本研究旨在检测产前约 1 个月的营养不良对聚乙二醇化牛粒细胞集落刺激因子产生的固有免疫反应的影响。将放牧牛按预期产犊日期和体况评分进行分组，并采用 2×2 析因设计随机分配到 2 个处理组。第一个因素是牛产前采食是否满足能量需求（自由采食）或限制为产前能量需求的 85%（限制采食）。第二个因素是在预期产犊日期前约 7d，每个采食组的一半牛注射聚乙二醇化牛粒细胞集落刺激因子，另一半注射生理盐水。处理在产犊当天重复进行。产犊前后采集血液样本进行全血细胞计数、生化分析以及中性粒细胞功能的体外评估，包括吞噬作用、髓过氧化物酶释放和氧化爆发。产前能量限制导致牛体重降低，血液中脂肪酸浓度升高（即＞0.4mmol/L）的牛比例增加，产犊前平均β-羟丁酸浓度升高。聚乙二醇化牛粒细胞集落刺激因子治疗增加了总白细胞、中性粒细胞、淋巴细胞和单核细胞计数。聚乙二醇化牛粒细胞集落刺激因子治疗导致中性粒细胞髓过氧化物酶释放增加。产前采食组没有影响，也没有观察到任何白细胞计数或功能测试的采食组×处理组互作。我们得出结论，聚乙二醇化牛粒细胞集落刺激因子治疗可显著增加中性粒细胞计数并增强其功能，表现为髓过氧化物酶释放增加。聚乙二醇化牛粒细胞集落刺激因子的反应不受产前能量摄入限制的影响。
