Cerebrospinal Fluid from Healthy Pregnant Women Does Not Harbor a Detectable Microbial Community

Area of Science:

• Neuroscience
• Microbiology
• Genomics

Background:

• Cerebrospinal fluid (CSF) has traditionally been considered sterile due to the blood-brain barrier.
• Recent findings have questioned this dogma, suggesting potential microbial presence in the central nervous system.

Purpose of the Study:

• To investigate the presence and activity of a microbial community in the CSF of healthy individuals.
• To determine if the CSF harbors a distinct microbiome independent of contamination.

Main Methods:

• Collected CSF, oral, and skin swab samples from 23 pregnant women.
• Utilized metagenomic and metatranscriptomic sequencing on 116 specimens.
• Included various controls (saline, swabs, buffers) to rule out contamination.

Main Results:

• Detected 620 nonredundant microbes across all samples, dominated by bacteria and viruses.
• CSF samples yielded only 26 nonredundant microbes, with no significant microbial diversity compared to other body sites.
• No active or viable microbes were identified in CSF after accounting for contamination sources.

Conclusions:

• The study found no strong evidence for a colonized microbial community in the CSF of healthy individuals.
• These findings reinforce the understanding of the CSF's internal environment and its implications for neurological health.
• Results aid in diagnostics, prevention, and therapeutics for neurological infections and disorders.