[A pilot study on the proteome of cerebrospinal fluid of Staphylococcus epidermidis meningitis in children]

Bacterial meningitis is a kind of central nervous system infection with a high incidence, disability and fatality in children. Prompt diagnosis and treatment are associated with an improved prognosis. Low positive rate of bacterial cultures of the cerebrospinal fluid (CSF) makes it difficult to make a definite diagnosis. This experiment aimed to investigate a proteome profile of normal CSF of Chinese children by two-dimensional polyacrydamide gel electrophoresis (2-DE), and to sieve the disease-specific proteins of Staphylococcus epidermidis meningitis (SeM) to provide basis for early diagnosis and treatment of SeM.

Four mL CSF samples were obtained respectively from SeM and normal children. The separated proteins with immobile pH gradient (IPG) 2-DE technology and protein spots were visualized by Coomassie Brilliant Blue staining. The stained 2-DE gels were scanned on the Imagescanner and pictures were obtained through Labscan software. The images were analyzed with PDQuest software and the differences of protein spots were compared between the SeM and normal children.

Mean protein spots of the 2-DE gels were 438 and 425 in the SeM and normal groups respectively. Twenty-five protein spots only occurred in normal CSF and 12 spots only occurred in the SeM group. The expression of 6 protein spots showed up-regulation and that of 19 showed down-regulation in the SeM group compared with that in the normal group.

A 2-DE profile of CSF proteome was successfully established in SeM and normal children through proteomic technique. By the differentiated analysis of these CSF 2-DE gels, the differences of CSF proteome profiles were found between SeM and normal children. Future analysis and identification of these spots will contribute to find out the disease specific proteins of SeM and to provide basis for early diagnosis and therapy of this disorder.