Do rhinoviruses follow the neutral theory? The role of cross-immunity in maintaining the diversity of the common cold

Journal ArticleOver 100 serotypes of rhinoviruses, one of the primary causes of the common cold, co-circulate in the human population. This high diversity makes it effectively impossible to develop a vaccine, even for those at risk of complications due to asthma or cystic fibrosis

Characterization of IgG and IgE Binding to Parvalbumin Derived from Commercially Important Fish Species

Rationale: Parvalbumin is recognized as pan-allergen in fish and frog. However, previous studies demonstrated that the IgE- and IgG-binding patterns to parvalbumins vary depending on the fish species. We aimed to use 3 anti-parvalbumin IgG and human IgE to investigate the contributing factors for the binding differences. Methods: Indirect enzyme-linked immunosorbent assay (ELISA) and IgG immunoblotting were used to determine the reactivity of the polyclonal anti-cod parvalbumin antibody and the commercially available, monoclonal anti-frog and anti-carp parvalbumin antibodies against raw muscle extracts of 25 fish species. Additionally, sera from 46 individuals with clinical history of fish allergy were analyzed for IgE reactivity to parvalbumin using indirect ELISA. Inhibition ELISAwas performed to determine the effects of heating and calcium on IgG-binding to parvalbumin. Results: The 3 IgG antibodies demonstrated varying specificity for different fish species. Polyclonal anti-cod parvalbumin antibody showed reactivity to a wider range of species, whereas the monoclonal anti-frog parvalbumin antibody showed the least cross-reactivity. The binding of the 3 IgG antibodies to parvalbumin was unaffected by heating, but the absence of calcium abolished the binding. IgE reactivity to cod parvalbumin or cod extracts were observed in \u3e 50% of individuals’ sera, whereas \u3c 0.1% of the sera showed reactivity to tuna and swordfish extracts. Both IgG and IgE antibodies showed low reactivity to tuna and swordfish that are apparently deficient in parvalbumin. Conclusions: These results suggested that the antibodies’ specificity to parvalbumins in various fish species is associated with the parvalbumin expression, its structural conformation, and the primary structure of antigenic determinations on parvalbumin

Identification and Analysis of the IgE Binding by Parvalbumin and Other Potential Allergens in Different Fish and Frog Species

Rationale: Serological cross-reactivity to different fish and frog species is common among fish-allergic individuals.We examined the intra- and inter-individual diversity in IgE responses of fish-allergic subjects to various fish and frog species and identified novel allergens besides parvalbumin. Methods: Sera from 38 subjects with a clinical history of fish allergy were analyzed for IgE-binding profiles to crude extracts of 26 raw fish and frog species, and purified cod and carp parvalbumin using IgE-immunoblotting. Sera of 7 subjects showing similar IgE-binding profiles in the IgEimmmunoblotting were pooled to identify potential allergens in pilchard, herring, cod, cusk, and rainbow trout using two-dimensional electrophoresis (2D) combined with IgE-immunoblotting and liquid chromatography-tandem mass spectrometry. Results: IgE-immunoblotting demonstrated great diversity among the fish-allergic individuals with respect to the IgE-binding to the parvalbumins and non-parvalbumin proteins in fish and frog species. Of the 38 individuals, 26 (68%) and 21 (55%) reacted to cod and carp parvalbumin, respectively. However, low IgE reactivity to parvalbumin from frog, mahi-mahi, and swordfish was observed. The pooled sera showed IgE-binding to parvalbumin and its corresponding isoforms separated by 2D in all 5 species. The IgE from pooled sera also recognized several novel fish allergens, including alpha actin, enolase, creatine kinase, glyceraldehyde 3-phosphate dehydrogenase, and fast myosin light chain proteins. Conclusions: The variation in IgE-binding depended on the individuals and fish species analyzed. The results suggested parvalbumin as the major cross-reactive allergens among fish species. Further characterization of the novel fish allergens is warranted at the molecular level using sera from additional fish-allergic subjects

Determination of Allergen Levels, Isoforms, and Their Hydroxyproline Modifications Among Peanut Genotypes by Mass Spectrometry

The recently published reference genome of peanuts enables a detailed molecular description of the allergenic proteins of the seed. We used LC-MS/MS to investigate peanuts of different genotypes to assess variability and to better describe naturally occurring allergens and isoforms. Using relative quantification by mass spectrometry, minor variation of some allergenic proteins was observed, but total levels of Ara h 1, 2, 3, and 6 were relatively consistent among 20 genotypes. Previously published RPHPLC methodology was used for comparison. The abundance of three Ara h 3 isoforms were variable among the genotypes and contributed to a large proportion of total Ara h 3 where present. Previously unpublished hydroxyproline sites were identified in Ara h 1 and 3. Hydroxylation did not vary significantly where sites were present. Peanut allergen composition was largely stable, with only some isoforms displaying differences between genotypes. The resulting differences in allergenicity are of unknown clinical significance but are likely to be minor. The data presented herein allow for the design of targeted MS methodology to allow the quantitation and therefore control of peanut allergens of clinical relevance and observed variability

Evaluation and Comparison of the Species-Specificity of 3 Antiparvalbumin IgG Antibodies

Parvalbumin is a pan-allergen in fish and frogs that triggers IgE-mediated reactions in fish-allergic individuals. Previous studies demonstrated that antibodies raised against fish and frog parvalbumins displayed varying specificity for different fish species, and thus, the applicability of these antibodies for potential use in immunoassays to detect fish residues were limited. We aimed to determine the specificity of 3 IgG antibodies for various fish species. Indirect enzyme-linked immunosorbent assay (ELISA) and IgG-immunoblotting were used to compare the reactivity of the polyclonal anticod parvalbumin antibody and the commercially available, monoclonal antifrog and monoclonal anticarp parvalbumin antibodies against raw muscle extracts of 29 fish species. All antibodies demonstrated varying specificities for different fish species. Of the 3 antibodies, the polyclonal anticod parvalbumin antibody is the most suitable for the detection of fish parvalbumins, as it showed reactivity to the widest range of species, including herring, pilchard, carp, pike, cod, pollock, haddock, cusk, hake, bluegill, tilapia, bass, grouper, trout, catfish, and perch, although detection was still limited for several key fish species