Spatial distribution of alpha-gal in Ixodes ricinus - A histological study
TICKS AND TICK-BORNE DISEASES
Authors: Fischer, Joerg; Riel, Simon; Fehrenbacher, Birgit; Frank, Alisa; Schaller, Martin; Biedermann, Tilo; Hilger, Christiane; Mackenstedt, Ute
Abstract
Alpha-gal syndrome is a complex allergic disease in humans that is caused by specific IgE (sIgE) against the carbohydrate galactose-alpha-1,3 -galactose (alpha-gal). Tick saliva contains alpha-gal, and tick bites are considered a major cause of the induction of alpha-gal-sIgE. The origin of alpha-gal in tick saliva remains unclarified. The presence of alpha-gal in tick tissue was visualized in this study to provide an overview of the spatial distribution of alpha-gal and to further elucidate the origin of alpha-gal in tick saliva. Fed and unfed Ixodes ricinus females were examined by histology, immunohistochemistry, immunofluorescence, transmission electron microscopy and immunoelectron microscopy using the alpha-gal-specific monoclonal antibody M86 and Marasmius oreades agglutinin (MOA) lectin. Alpha-gal epitopes were detected in the midgut, hemolymph and salivary glands, and the immunofluorescence analysis revealed signs of the endocytosis of alpha-gal-containing constituents during the process of hematophagy. Alpha-gal epitopes in endosomes of the digestive gut cells of the ticks were observed via immunoelectron microscopy. Alpha-gal epitopes were detected in dried droplets of hemolymph from unfed ticks. Intense staining of alpha-gal epitopes was found in type II granular acini of the salivary glands of fed and unfed ticks. Our data suggest that alpha-gal is not ubiquitously expressed in tick tissue but is present in both fed and unfed ticks. The findings also indicate that both the metabolic incorporation of constituents from a mammalian blood meal and endogenous production contribute to the presence of alpha-gal epitopes in ticks.
Small Gal sums and applications
JOURNAL OF THE LONDON MATHEMATICAL SOCIETY-SECOND SERIES
Authors: de la Breteche, Regis; Munsch, Marc; Tenenbaum, Gerald
Abstract
In recent years, maximizing Gal sums regained interest due to a firm link with large values ofL-functions. In the present paper, we initiate an investigation of small sums of Gal type, with respect to theL1-norm. We also consider the intertwined question of minimizing weighted versions of the usual multiplicative energy. We apply our estimates to: (i) a logarithmic refinement of Burgess' bound on character sums, improving previous results of Kerr, Shparlinski and Yau; (ii) an improvement on earlier lower bounds by Louboutin and the second author for the number of nonvanishing theta functions associated to Dirichlet characters; and (iii) new lower bounds for low moments of character sums.