The salivary gland of hard ticks is a highly innervated tissue where multiple intertwined axonal projections enter each individual acini. In the present study, we investigated the ultrastructural architecture of axonal projections within granular salivary gland type II and III acini of Ixodes ricinus female. Using immunogold labeling, we specifically examined the associations of SIFamide neuropeptide, SIFamide receptor (SIFa_R), neuropeptide pigment dispersing factor (PDF), and the invertebrate-specific D1-like dopamine receptor (InvD1L), with acinar cells. In both acini types, SIFamide-positive axons were found to be in direct contact with either basal epithelial cells or a single adlumenal myoepithelial cell in close proximity to the either the acinar duct or its valve, respectively. Accordingly, SIFa_R staining correlated with SIFamide-positive axons in both basal epithelial and myoepithelial cells. Immunoreactivity for both InvD1L and PDF (type II acini exclusively) revealed positive axons radiating along the acinar lumen. These axons were primarily enclosed by the adlumenal myoepithelial cell plasma membrane and interstitial projections of ablumenal epithelial cells. Our study has revealed the detailed ultrastructure of I. ricinus salivary glands, and provides a solid baseline for a comprehensive understanding of the cell-axon interactions and their functions in this essential tick organ.
- MeSH
- axony metabolismus ultrastruktura MeSH
- Ixodidae MeSH
- klíště ultrastruktura MeSH
- receptory dopaminové metabolismus MeSH
- slinné žlázy inervace metabolismus ultrastruktura MeSH
- transmisní elektronová mikroskopie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of the study is co-localization of N-glycans with fucose attached to N-acetylglucosamine in α1,3 linkage, that belong to immunogenic carbohydrate epitopes in humans, and N-glycans with α1,6-core fucose typical for mammalian type of N-linked glycosylation. Both glycan epitopes were labelled in cryosections of salivary glands isolated from the tick Ixodes ricinus. Salivary glands secrete during feeding many bioactive molecules and influence both successful feeding and transmission of tick-borne pathogens. For accurate and reliable localization of labelled glycans in both fluorescence and scanning electron microscopes, we used carbon imprints of finder or indexed EM grids on glass slides. We discuss if the topographical images can provide information about labelled structures, the working setting of the field-emission scanning electron microscope and the influence of the detector selection (a below-the-lens Autrata improved YAG detector of back-scattered electrons; in-lens and conventional Everhart-Thornley detectors of secondary electrons) on the imaging of gold nanoparticles, quantum dots and osmium-stained membranes.
- MeSH
- barvení a značení metody MeSH
- elektronová kryomikroskopie přístrojové vybavení metody MeSH
- fluorescenční mikroskopie přístrojové vybavení metody MeSH
- klíště * metabolismus ultrastruktura MeSH
- mikroskopie elektronová rastrovací přístrojové vybavení metody MeSH
- proteiny členovců metabolismus MeSH
- proteoglykany metabolismus MeSH
- sklo MeSH
- slinné proteiny a peptidy metabolismus MeSH
- slinné žlázy * metabolismus ultrastruktura MeSH
- uhlík MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A site-specific glycosylation of salivary glands (SGs) isolated from unfed and partially fed Ixodes ricinus females was identified with the use of lectin affinity labeling on sections and western blots of SDS-PAGE gels. The results revealed that secretory granules of a, b, and c cells of the type II acinus and e and f cells of the type III acinus are glycosylated. In partially engorged tick SGs, 2 subtypes of c cells were distinguished. The granules of c1 cells contained mannose, N-acetyl-D-glucosamine, and sialic acid residues. The granules of b, c2, and e cells exhibited complex glycoconjugates rich in mannose, N-acetyl-D-glucosamine, galactose, N-acetyl-D-galactosamine, and a moderate amount of sialic acid. The granules of f cells contained N-acetyl-D-glucosamine and mannose moieties. Type III acini surfaces were covered with mannose-specific ConA binding sites. Except the granules of salivary cells, sialic acid-specific lectins MAA II and SNA strongly bound cuticular structures of alveolar ducts, and weakly with the cuticular spiral thread of excretory salivary ducts. The total sialic acid level in SG homogenates isolated from partially fed females was determined by the thiobarbituric acid method. Sialic acid, which has been found during the development of a few insect species, has not been reported in ticks as yet.
- MeSH
- elektronová mikroskopie MeSH
- financování organizované MeSH
- fluorescenční mikroskopie MeSH
- glykosylace MeSH
- klíště metabolismus ultrastruktura MeSH
- kyselina N-acetylneuraminová analýza MeSH
- lektiny metabolismus MeSH
- sacharidy analýza MeSH
- sekreční vezikuly metabolismus ultrastruktura MeSH
- slinné žlázy cytologie metabolismus ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- MeSH
- antibakteriální látky terapeutické užití MeSH
- Borrelia burgdorferi klasifikace patogenita MeSH
- Ehrlichia patogenita ultrastruktura MeSH
- klíšťata anatomie a histologie patogenita růst a vývoj MeSH
- klíště patogenita ultrastruktura MeSH
- lidé MeSH
- nemoci přenášené klíšťaty diagnóza etiologie prevence a kontrola MeSH
- vakcíny aplikace a dávkování chemie MeSH
- Check Tag
- lidé MeSH
