This doctoral thesis, supervised by José Manuel Cuevas, provides insights into the virome composition of plasma from human blood donors. Part of the results have been published in the journals Scientific Reports, and Viruses. The thesis was defended on July 22, 2022.
The development of viromics has led to the discovery of a remarkable number of new virus sequences, which has provided insight into the composition of viral communities in multiple environments, including the human body. In this thesis, entitled "Characterization of virome in plasma from blood donors", plasma from samples from the Transfusion Center of the Valencian Community has been studied. For this purpose, a protocol for the enrichment of the viral fraction has been developed together with a subsequent bioinformatic analysis of the data obtained after sequencing. In the taxonomic classification of the samples, it has been found that most of the reads obtained belong to the family Anelloviridae. Phylogenetic analyses using the coding sequence of these genomes have revealed an enormous diversity and a considerable number of potentially new species have been observed. In addition, a small fraction of the samples has been analyzed at the individual level, which has made it possible to observe that each individual has its own personal and distinctive set of anelloviruses. On the other hand, in a much smaller percentage due to their low prevalence, some samples have been detected presenting human pegivirus readings, which belongs to the Pegivirus genus and, in turn, to the Flaviviridae family. Human anelloviruses and pegiviruses are considered orphan viruses, because they do not present any associated disease. Therefore, studies of the plasma virome can be used to try to understand the role of these viruses on the health and disease of individuals.
María Cebriá carried out her doctoral research under the supervision of Jose Manuel Cuevas, University of Valencia Associated professor of Genetics at the Institute for Integrative Systems Biology I2SysBio (UV-CSIC). The examining board was formed by Mireia Coscollà (I2SysBio), Xavier López Labrador (Fisabio), and Antonio Alcamí (CBM Severo Ochoa, CSIC-UAM), who granted the thesis as outstanding.
