Raymond Steven L, Mathias Brittany J, Murphy Tyler J, Rincon Jaimar C, López María Cecilia, Ungaro Ricardo, Ellett Felix, Jorgensen Julianne, Wynn James L, Baker Henry V, Moldawer Lyle L, Irimia Daniel, Larson Shawn D
Department of Surgery, University of Florida College of Medicine, Gainesville, Fla.
Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, Fla.
Transl Res. 2017 Dec;190:4-15. doi: 10.1016/j.trsl.2017.08.003. Epub 2017 Sep 1.
Neutrophils play a crucial role in combating life-threatening bacterial infections in neonates. Previous studies investigating neonatal cell function have been limited because of restricted volume sampling. Here, using novel microfluidic approaches, we provide the first description of neutrophil chemotaxis and transcriptomics from whole blood of human term and preterm neonates, as well as young adults. Ex vivo percent cell migration, neutrophil velocity, and directionality to N-formylmethionyl-leucyl-phenylalanine were measured from whole blood using time-lapse imaging of microfluidic chemotaxis. Genome-wide expression was also evaluated in CD66b cells using microfluidic capture devices. Neutrophils from preterm neonates migrated in fewer numbers compared to term neonates (preterm 12.3%, term 30.5%, P = 0.008) and at a reduced velocity compared to young adults (preterm 10.1 μm/min, adult 12.7 μm/min, P = 0.003). Despite fewer neutrophils migrating at slower velocities, neutrophil directionality from preterm neonates was comparable to adults and term neonates. 3607 genes were differentially expressed among the 3 groups (P < 0.001). Differences in gene expression between neutrophils from preterm and term neonates were consistent with reduced pathogen recognition and antimicrobial activity but not neutrophil migration, by preterm neonates. In summary, preterm neonates have significant disturbances in neutrophil chemotaxis compared to term neonates and adults, and these differences in phenotype appear at the transcriptional level to target inflammatory pathways in general, rather than in neutrophil migration and chemotaxis.
中性粒细胞在抵抗新生儿危及生命的细菌感染中发挥着关键作用。以往关于新生儿细胞功能的研究由于样本量有限而受到限制。在此，我们采用新型微流控方法，首次描述了足月和早产新生儿以及年轻成年人全血中的中性粒细胞趋化性和转录组学。使用微流控趋化性的延时成像技术，从全血中测量了细胞迁移百分比、中性粒细胞速度以及对N-甲酰甲硫氨酰-亮氨酰-苯丙氨酸的方向性。还使用微流控捕获装置对CD66b细胞中的全基因组表达进行了评估。与足月新生儿相比，早产新生儿的中性粒细胞迁移数量较少（早产新生儿为12.3%，足月新生儿为30.5%，P = 0.008），且与年轻成年人相比速度降低（早产新生儿为10.1μm/min，成年人 为12.7μm/min，P = 0.003）。尽管迁移的中性粒细胞数量较少且速度较慢，但早产新生儿中性粒细胞的方向性与成年人和足月新生儿相当。三组之间有3607个基因差异表达（P < 0.001）。早产和足月新生儿中性粒细胞之间的基因表达差异与早产新生儿病原体识别和抗菌活性降低一致，但与中性粒细胞迁移无关。总之，与足月新生儿和成年人相比，早产新生儿的中性粒细胞趋化性存在显著紊乱，这些表型差异在转录水平上总体针对炎症途径，而非中性粒细胞迁移和趋化性。
