title: Comparison of the Functional microRNA Expression in Immune Cell Subsets of Neonates and Adults.
abstract: Diversity of biological molecules in newborn and adult immune cells contributes to differences in cell function and atopic properties. Micro RNAs (miRNAs) are reported to involve in the regulation of immune system. Therefore, determining the miRNA expression profile of leukocyte subpopulations is important for understanding immune system regulation. In order to explore the unique miRNA profiling that contribute to altered immune in neonates, we comprehensively analyzed the functional miRNA signatures of eight leukocyte subsets (polymorphonuclear cells, monocytes, CD4+T cells, CD8+T cells, natural killer cells, B cells, plasmacytoid dendritic cells, and myeloid dendritic cells) from both neonatal and adult umbilical cord and peripheral blood samples, respectively. We observed distinct miRNA profiles between adult and neonatal blood leukocyte subsets, including unique miRNA signatures for each cell lineage. Leukocyte miRNA signatures were altered after stimulation. Adult peripheral leukocytes had higher let-7b-5p expression levels compared to neonatal cord leukocytes across multiple subsets, irrespective of stimulation. Transfecting neonatal monocytes with a let-7b-5p mimic resulted in a reduction of LPS-induced interleukin (IL)-6 and TNF-α production, while transfection of a let-7b-5p inhibitor into adult monocytes enhanced IL-6 and TNF-α production. With this functional approach, we provide intact differential miRNA expression profiling of specific immune cell subsets between neonates and adults. These studies serve as a basis to further understand the altered immune response observed in neonates and advance the development of therapeutic strategies.
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Hong-Ren
authors.initials: HR
authors.lastname: Yu
authors.affiliation: Department of Obstetrics, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Te-Yao
authors.initials: TY
authors.lastname: Hsu
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Hsin-Chun
authors.initials: HC
authors.lastname: Huang
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Ho-Chang
authors.initials: HC
authors.lastname: Kuo
authors.affiliation: Genomics and Proteomics Core Laboratory, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Sung-Chou
authors.initials: SC
authors.lastname: Li
authors.affiliation: Institute of Biomedical Sciences, Mackay Medical College, New Taipei City, Taiwan; Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming University, Taipei, Taiwan.
authors.forename: Kuender D
authors.initials: KD
authors.lastname: Yang
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Graduate Institute of Clinical Medical Science, Chang Gung University College of Medicine , Kaohsiung , Taiwan.
authors.forename: Kai-Sheng
authors.initials: KS
authors.lastname: Hsieh
keywords: cord blood; let-7b; leukocyte subsets; microRNA; monocytes