Vector-borne infectious diseases (8)Zoonotic diseases and public health (8)Viral gastroenteritis research and epidemiology (4)Viral Infections and Vectors (4)Animal Disease Management and Epidemiology (3)
Vaz-Rodrigues R, Mazuecos L, Contreras M, González-García A, Rafael M, et al.
Scientific reports •
The alpha-Gal syndrome (AGS) evolved as a catastrophic selection associated with anti-α-Gal IgM/IgG protective response against pathogen infection and tick-borne food allergy caused by IgE-type antibodies against this glycan present in glycoproteins and glycolipids from mammalian meat and derived products. The immune response to α-Gal is modulated by tick salivary proteins with and without α-Gal modifications in combination with tick saliva non-protein fraction. Herein, we characterized the role of tick salivary proteins, metalloprotease and allergen-like p23 in AGS and protection against tuberculosis in the AGS zebrafish animal model. Metalloprotease and p23 are involved in allergic reactions after mammalian meat consumption through upregulation of pro-inflammatory protein-coding genes prkdc, tlr2, tnfα and il1b. Challenge with Mycobacterium marinum activated Th1-mediated immune protective response with reduced pathogen infection, ameliorating Th2-associated allergic reactions associated with AGS. These results highlight molecular mechanisms modulated by tick proteins in response to α-Gal and provide insights to reduce AGS impact on human health.
Vaz-Rodrigues R, Rafael M, Carniato D, de la Fuente J
Annals of medicine •
Tick bites and tick-borne diseases (TBDs) are a worldwide concern, with growing evidence of an ongoing spread and emergence of new cases. This study applied a participatory citizen science across Spain and Portugal to gather public perspectives on the impact of tick bites, the presence of TBDs and a potential connection with the α-Gal syndrome (AGS). Data collected from the questionnaire (380 participants) was geographically represented using QGIS Geographic Information System and fitted into multiple generalized linear models (GLMs). Statistical analysis identified factors influencing the occurrence of local skin reactions post-tick bite, AGS-compatible symptoms and visits to health centers following tick exposure. Results showed that the probability of developing localized skin reactions to tick bites rises with increasing age ( = 0.006, < 0.05), the occurrence of multiple bites ( = 0.006, = 0.063) and among individuals bitten in the center-north part of the peninsula ( = 0.006, = 0.058). Seeking medical care following tick bite was reported by 21.6% of respondents, being more common in first-time bite cases ( = 0.002, p < 0.01), men ( = 0.002, < 0.01) or individuals presenting localized skin symptoms ( = 0.002, < 0.05). Although 38 inquiries (10.0%) showed signs of AGS, only 3 had received a formal diagnosis, with the odds of developing this disease marginally rising with advancing age ( = 0.215, = 0.066). This study provides valuable insights that should be considered to improve TBDs surveillance and diagnostic strategies, as well as developing preventive measures to reduce tick bite exposure and TBD cases.Developing local skin reactions to tick bites increases with age, multiple bites and in individuals bitten in central-northern Iberia.Seeking medical care following a tick bite is more common in first-time bite cases, men or individuals with local skin symptoms.Although 38 inquiries (10.0%) showed signs of AGS, only 3 were formally diagnosed, with risk increasing with age.
Díaz-Sánchez S, Vaz-Rodrigues R, Contreras M, Rafael M, Villar M, et al.
Microbiological research •
The α-Gal syndrome (AGS) is an IgE-mediated tick borne-allergy that results in delayed anaphylaxis to the consumption of mammalian meat and products containing α-Gal. Considering that α-Gal-containing microbiota modulates natural antibody production to this glycan, this study aimed to evaluate the influence on tick salivary compounds on the gut microbiota composition in the zebrafish (Danio rerio) animal model. Sequencing of 16 S rDNA was performed in a total of 75 zebrafish intestine samples, representing different treatment groups: PBS control, Ixodes ricinus tick saliva, tick saliva non-protein fraction (NPF), tick saliva protein fraction (PF), and tick saliva protein fractions 1-5 with NPF (F1-5). The results revealed that treatment with tick saliva and different tick salivary fractions, combined with α-Gal-positive dog food feeding, resulted in specific variations in zebrafish gut microbiota composition at various taxonomic levels and affected commensal microbial alpha and beta diversities. Metagenomics results were corroborated by qPCR, supporting the overrepresentation of phylum Firmicutes in the tick saliva group, phylum Fusobacteriota in group F1, and phylum Cyanobacteria in F2 and F5 compared to the PBS-control. qPCRs results at genus level sustained significant enrichment of Plesiomonas spp. in groups F3 and F5, Rhizobium spp. in NPF and F4, and Cloacibacterium spp. dominance in the PBS control group. This study provides new results on the role of gut microbiota in allergic reactions to tick saliva components using a zebrafish model of AGS. Overall, gut microbiota composition in response to tick saliva biomolecules may be associated with allergic reactions to mammalian meat consumption in AGS.