Extracellular Vesicles and Asthma—More Than Just a Co-Existence

Extracellular vesicles (EVs) are membranous structures, which are secreted by almost every cell type analyzed so far. In addition to their importance for cell-cell communication under physiological conditions, EVs are also released during pathogenesis and mechanistically contribute to this process. Here we summarize their functional relevance in asthma, one of the most common chronic non-communicable diseases. Asthma is a complex persistent inflammatory disorder of the airways characterized by reversible airflow obstruction and, from a long-term perspective, airway remodeling. Overall, mechanistic studies summarized here indicate the importance of different subtypes of EVs and their variable cargoes in the functioning of the pathways underlying asthma, and show some interesting potential for the development of future therapeutic interventions. Association studies in turn demonstrate a good diagnostic potential of EVs in asthma.     

Sensitization to Sitophilus granarius in selected suburban population of South Poland

Storage insects may cause occupational allergies in humans. The identification of the prevalence of IgE reactions were measured from protein fractions prepared from multiple life stage of granary weevil Sitophilus granarius [SG] is reported. Sera of 30 patients from a suburban population of Upper Silesia (South Poland) were tested for the presence of IgE antibodies to antigens from larvae, pupae and adults of both sexes of the beetle. To identify protein fractions containing potential allergens, proteins collected from four life stages of granary weevil were fractionated by SDS-PAGE and probed with anti-human, anti-IgE monoclonal antibodies. The proteins were fractionated by SDS PAGE and identified by Western blot. The patients’ antibodies against particular antigens were identified using anti-human anti-IgE monoclonal antibody. The conducted immunological analysis showed the existence of many protein fractions for each life stage of SG which give positive reactions with IgE antibodies. The largest number of allergenic potential fractions was shown in pupae (60 protein fractions) while the smallest amount was shown in larvae (44 protein fractions). Summarizing, the obtained results suggest the existence of many protein fractions with an allergenic potential multiple life stages of SG. This indicates that all developmental stages of SG may be a serious source of antigens and potential risk factors for the exposed persons.     

‘Nickel Allergy’ arising from decorative nickel plated and alloyed articles: prevention at source

This work builds on papers published in Transactions during 2015 and 2018 reporting research into low-cost commercial methods for the prevention of nickel release from decorative nickel plated articles, rendering them suitable for placement on the European market in accordance with the requirements of REACH. ‘Nickel Allergy’ sometimes occurs when nickel-containing articles are in direct and prolonged contact with the skin, leading to corrosion of elemental nickel by sweat, liberating sufficient nickel ions to be absorbed through the skin and initiate an allergenic effect. The EU ‘Nickel Restrictions’ impose limits on the amount of nickel released from articles intended for use in this application, but permits a non-nickel surface coating that can ensure the rate of nickel release does not exceed 0.5?µg?cm^?2 week^?1 after 2 years of normal use. The official tests for coated items are simulated wear and corrosion under EN 12472 followed by determination of nickel release under EN 1811. Earlier work concluded that suitable barrier coatings over bright electrodeposited nickel are regular chromium deposited from a hexavalent electrolyte, microporous trivalent chromium from a chloride electrolyte and UV cured PU electrophoretic coatings. Further tests reported here focused on nickel release from examples of wearable articles such as costume jewellery and watch cases. A typical flash coating of gold over bright nickel is thin and porous and being more noble, causes the rate of nickel release to be accelerated; but this can be prevented by an intermediate barrier coating of electrodeposited palladium. To round out the relevance of this study on wearable articles, nickel release tests were also conducted on nickel-containing Grades 304 (UNS S30400) and 316 (UNS S31600) austenitic stainless steels, plus a typical gold alloy containing nickel. All passed the nickel release tests satisfactorily.     

Absence of allergenic residues in experimental and commercial wines fined with caseinates

The possible presence of allergenic residues in wines treated with one of the potassium caseinates used as fining agents has been investigated.     

Apple Allergy: The cDNA Sequence of the Major Allergen of Apple,Determined by Performing PCR with a Primer Based on the N-Terminal Amino Acid Sequence,is Highly Homologous to the Sequence of the Major Birch Pollen Allergen

Considering the known N-terminal amino acid sequence of the major apple allergen, a polymerase chain reaction (PCR) primer was selected to amplify cDNA encoding this protein. A single PCR product was obtained, cloned into Escherichia coli and subsequently sequenced. The missing 5′-end of the apple cDNA sequence was obtained by a 5′-RACE method. The cDNA sequence showed 72% identity with the coding region of one of the known isoforms of Bet v 1, the major allergen of birch pollen. The deduced amino acid sequence resulted in a 158-residue protein with a calculated molecular mass of 17·5 kDa and 63% amino acid sequence identity to Bet v 1. In addition, further protein alignments showed a high degree of identity with allergens from other tree pollens and some ‘pathogenesis-related proteins’ from food plants. According to international regulations the allergen was termed Mal d 1 for this protein, it being the first major allergen discovered and characterised in fruits of apple (Malus domestica).     

Resolvin D2 and Resolvin D1 Differentially Activate Protein Kinases to Counter-Regulate Histamine-Induced [Ca2+]i Increase and Mucin Secretion in Conjunctival Goblet Cells

Resolvin (Rv) D2 and RvD1 are biosynthesized from docosahexaenoic acid (DHA) and promote resolution of inflammation in multiple organs and tissues, including the conjunctiva. Histamine is a mediator produced by mast cells in the conjunctiva during the allergic response. We determined the interaction of RvD2 with histamine and its receptor subtypes in cultured conjunctival goblet cells and compared them with RvD1 by measuring intracellular [Ca²⁺] and mucous secretion. Treatment with RvD2 significantly blocked the histamine-induced [Ca²⁺]_i increase as well as secretion. RvD2 and RvD1 counter-regulate different histamine receptor subtypes. RvD2 inhibited the increase in [Ca²⁺]_i induced by the activation of H1, H3, or H4 receptors, whereas RvD1 inhibited H1 and H3 receptors. RvD2 and RvD1 also activate distinct receptor-specific protein kinases to counter-regulate the histamine receptors, probably by phosphorylation. Thus, our data suggest that the counter-regulation of H receptor subtypes by RvD2 and RvD1 to inhibit mucin secretion are separately regulated.