SIALOME AND SALIVARY MICROTRANSCRIPTOME OF ORNITHODOROS SP., TICK VECTORS OF AFRICAN SWINE FEVER. DESIGN AND EVALUATION OF MULTICOMPONENT ANTI-ORNITHODOROS VACCINES. MULTIVAC
Referencia: RTI2018-098297-B-I00
Funding Entity: Ministry of Science, Innovation and Universities (MCIU), State Research Agency (AEI) and European Regional Development Fund (ERDF).
Duration: 2019 – 2022
Principal Investigators: Ricardo Pérez Sánchez, Ana Oleaga Pérez.
Participants: María González Sánchez, Sergio González Pérez.
Summary
Ornithodoros erraticus and Ornithodoros moubata are the main vectors of African Swine Fever (ASF) and Human Recurrent Fever (HRF) in the Mediterranean and Africa. The presence of these argasids in the anthropogenic environment hinders the eradication of these diseases from endemic areas, aggravates the constant threat of reintroduction of ASF in countries from which it was eradicated and may contribute to its endemization and persistence in recently infected countries (Eastern Europe, Russia, Caucasus, China and Southeast Asia).
The prevention and control of both diseases requires the elimination of ornithodonts from the anthropogenic environment, but the application of acaricides as a method of control is ineffective, making necessary the development of alternative methods of control, of which the most promising are the anti-tick vaccines, especially those based on hidden antigens of the intestine and salivary antigens.
Both types of antigens are part of the tick-host interface and play vital roles in the physiological processes specifically developed by ticks to adapt to hematophagy, so these antigens have been successfully used as targets for the development of anti-tick vaccines, although neither of these antigen types alone have been 100% effective vaccines. The combined use of salivary and intestinal antigens in multi-antigenic vaccines will provide greater efficacy, since by simultaneously addressing targets involved in different biological processes, they are expected to exert synergistic protective effects.
In previous projects (AGL2013-42745-P), the myalomes (transcriptome+gut proteome) of O. erraticus and O. moubata were obtained and from them a repertoire of protective intestinal antigens was identified and validated that can be used, together with salivary antigens, in multiantigenic vaccines for the control of these ornithodorans. It is urgent to identify new salivary antigens more effective in both species and for this it is essential to obtain and characterize their sialomes (salivary transcriptome+proteome).
This project addresses the identification and validation of protective salivary antigens by means of a vaccinomic approach, which will be developed through the following specific objectives: obtaining salivary gland transcriptomes and saliva micro-transcriptomes (microRNAs), including validation of RNA-seq results by quantitative PCR; obtaining and quantifying saliva proteomes; integrated analysis of all omics data and in silico selection of vaccine candidates; production of candidates in recombinant form, evaluation of their protective efficacy in animal vaccination trials and, finally, formulation of multi-antigenic vaccines and evaluation of their protective effect.
