Chen Juncao, Huang Weiben, Zhang Hong, Peng Xiangwen, Yang Jun, Yang Yong, Su Jinzhen, Wang Siyao, Zhou Wei
Department of Neonatology, Guangzhou Women and Children's Medical Centre, Guangzhou Medical University, Guangzhou, China.
Department of Neonatology, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, China.
Front Pediatr. 2022 Aug 16;10:972032. doi: 10.3389/fped.2022.972032. eCollection 2022.
Hydrocephalus in bacterial meningitis (BM) is a devastating infectious neurological disease and the proteins and pathways involved in its pathophysiology are not fully understood.
Label-free quantitative (LFQ) proteomics analyses was used to identify differentially expressed proteins (DEPs) in cerebrospinal fluid (CSF) samples from infants with hydrocephalus and bacterial meningitis (HBM group, = 8), infants with bacterial meningitis (BM group, = 9); and healthy infants (N group, = 11). Bioinformatics analysis was subsequently performed to investigate Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enriched signaling pathways of these DEPs. Six proteins (AZU1, COX4I1, EDF1, KRT31, MMP12, and PRG2) were selected for further validation enzyme-linked immunosorbent assay (ELISA).
Compared with BM group and N group, HBM group had a higher whole CSF protein level (5.6 ± 2.7 vs. 1.7 ± 1.0 vs. 1.2 ± 0.5 g/l) and lower whole CSF glucose level (0.8 ± 0.6 vs. 1.8 ± 0.7 vs. 3.3 ± 0.8 mmol/l) (both < 0.05). Over 300 DEPs were differentially expressed in HBM group compared with BM group and BM compared with N group, of which 78% were common to both. Cluster analysis indicated that the levels of 226 proteins were increased in BM group compared with N group and were decreased in HBM group compared with BM group. Bioinformatics analysis indicated the involvement of the cell adhesion, immune response and extracellular exosome signaling were significantly enriched in HBM compared with BM group and BM compared with N group. 267 DEPs were identified between HBM group with N group, KEGG analysis indicated that DEPs mainly involved in filament cytoskeleton and immune response. The ELISA results further verified that the expression levels of AZU1 were significantly different from among three groups (both < 0.05).
This is the first reported characterization of quantitative proteomics from the CSF of infants with HBM. Our study also demonstrated that AZU1 could be a potential biomarker for the diagnosis of hydrocephalus in bacterial meningitis.
细菌性脑膜炎（BM）相关脑积水是一种严重的感染性神经疾病，其病理生理学所涉及的蛋白质和信号通路尚未完全明确。
采用无标记定量（LFQ）蛋白质组学分析，以鉴定脑积水合并细菌性脑膜炎婴儿（HBM组，n = 8）、细菌性脑膜炎婴儿（BM组，n = 9）及健康婴儿（N组，n = 11）脑脊液（CSF）样本中的差异表达蛋白（DEP）。随后进行生物信息学分析，以研究这些DEP的基因本体论（GO）功能注释及京都基因与基因组百科全书（KEGG）富集信号通路。选取6种蛋白（AZU1、COX4I1、EDF1、KRT31、MMP12和PRG2），通过酶联免疫吸附测定（ELISA）进行进一步验证。
与BM组和N组相比，HBM组的脑脊液总蛋白水平更高（5.6±2.7 vs. 1.7±1.0 vs. 1.2±0.5 g/l），脑脊液葡萄糖总水平更低（0.8±0.6 vs. 1.8±0.7 vs. 3.3±0.8 mmol/l）（均P<0.05）。与BM组相比，HBM组中有300多种DEP存在差异表达；与N组相比，BM组中也有差异表达，其中78%是两组共有的。聚类分析表明，与N组相比，BM组中226种蛋白水平升高；与BM组相比，HBM组中这些蛋白水平降低。生物信息学分析表明，与BM组相比，HBM组以及与N组相比BM组中，细胞黏附、免疫反应和细胞外囊泡信号传导的参与情况显著富集。在HBM组与N组之间鉴定出267种DEP，KEGG分析表明DEP主要参与丝状细胞骨架和免疫反应。ELISA结果进一步证实，三组间AZU1的表达水平存在显著差异（均P<0.05）。
这是首次报道对HBM婴儿脑脊液进行定量蛋白质组学的特征分析。我们的研究还表明，AZU1可能是细菌性脑膜炎脑积水诊断的潜在生物标志物。
