Study of microbial species in extracellular vesicles of sclerosis multiple patients
Extracellular vesicles (EVs) are released by most cell types and are implicated in several biological and pathological processes, including multiple sclerosis (MS). In this study we performed RNA sequencing to analyze the diversity of microorganisms by assignment of reads using different taxa profilers. To diminish the risk of false positive biases derived from sample handling, we performed a similar analysis on EVs derived from known cultured bacterial species, as well as artificially-generated samples. Overall, we detect a range of microbial species in MS and healthy control (HC) samples, that are not detected in control samples, as well as species with differential abundance between MS and HC samples. These results reveal the relevance of putative communication of microbial species using EVs as a communication vector. Overall design: Peripheral blood from 20 MS patients and 10 HC was collected by venipuncture in EDTA tubes and centrifuged to separate the plasma from the cellular fraction. Additionally, cultured samples of from L. acidophilus and B. lactis were also retrieved. To isolate EVs, plasma aliquots were double-centrifuged to pellet EVs. The pellet was then resuspended with 100 µL of DPBS, and RNA was isolated using Trizol LS. Lastly, samples were pooled to fulfil a minimum input of 2 ug of RNA. rRNA was depleted from the total RNA sample and cDNA libraries were built. Paired-end sequencing was performed with Illumina HiSeq X Ten with an average of 40–50 × 10^6 reads obtained per sample.