A mathematical model for mugwort (Artemisia vulgaris L.) pollen forecasts

Pollen forecasts are a fundamental prerequisite to obtain prophylactic measures for allergic individuals. Mugwort belongs to the most relevant allergenic pollen types after grasses and birch. An approach to modeling of mugwort pollen concentrations has not been attempted previously in Germany. A process-oriented mathematical model for the relative local daily average mugwort airborne pollen concentration was developed on the basis of pollen and weather data measured during a 6-year period. The model depends on the daily minimum and maximum temperature, amount of precipitation and atmospheric pressure, which have to and can be supplied by measurement and prediction. The comparison of modeling results and pollen counting for an additional year confirms the fitness of the model. A computer program was written, which rests upon the model and supplies daily predictions of mugwort pollen flight during the period of the weather forecast. The latter should allow a pollen forecasting period of about 5 days, with an accuracy of about 32–63% explained variance, which in view of the low mugwort pollen counts (nine grains/m³ maximum in the validation year) represents a high relative measurement error. The mathematical model may serve to improve and rationalize of present pollen forecasts.     

The emission of mugwort pollen (Artemisia vulgaris L.) and its flight in the air

Summary Mugwort pollen flight and pollen emission are characterized by a distinct biological rhythm with emission in the early morning hours (6:00–11:00 a.m. CEST). Pollen traps at roof level monitor the daily and yearly variation of mugwort pollen flight later and in lower quantities than those installed at ground level because of the different daily variation of convection at various air levels. The daily variation of mugwort pollen flight can be described by mathematical functions. Because of these significant differences between the catch at different levels, the supposed high allergic potential of mugwort has to be discussed.     

Characterization of a coryneform isolate from fasciated mugwort (Artemisia vulgaris)

The morphological and physiological features of coryneform isolated from fasciated mugwort (Artemisia vulgaris) display many morphological similarities with the plant pathogenic corynebacteria, but differ from Corynebacterium fascians in exhibiting motility albeit in only a small proportion of each cell population, and by its ability to hydrolyze asculin, its failure to produce urease and differences in pigmentation. The isolate appears to be related to Corynebacterium fascians in its ability to cause fasciation but physiologically and biochemically it resembles Cornyebacterium poinsettiae and C. flaccumfaciens, both of which were transferred to the genus Curtobacterium.     

Structural analysis of the glycoprotein allergen Art v II from the pollen of mugwort (Artemisia vulgaris L.).

The glycoprotein allergen Art v II, from the pollen of mugwort (Artemisia vulgaris L.) was treated with peptide:N-glycosidase F (PNGase F) to release asparagine-linked oligosaccharides. The oligosaccharides were isolated by gel permeation chromatography and their structures determined by 500-MHz 1H NMR spectroscopy, fast atom bombardment-mass spectrometry, and high-pH anion-exchange chromatography. The high-mannose oligosaccharides Man5GlcNAc2, Man6GlcNAc2, Man7GlcNAc2, Man8GlcNAc2, and Man9GlcNAc2 were present in the ratios 2:49:19:24:6 and accounted for all the asparagine-linked oligosaccharides released from Art v II by PNGase F. The NH2-terminal amino acid sequences of Art v II and of four peptides generated by cyanogen bromide (CNBr) cleavage of deglycosylated Art v II were determined. The first 30 amino acid residues of Art v II did not contain any potential N-glycosylation sites. One potential N-glycosylation site was identified in one of the CNBr fragments. The native protein conformation was shown by enzyme-linked immunosorbent assay inhibition assays to be essential for the binding of rabbit IgG to Art v II and for the binding of human IgE to the major IgE-binding epitope(s) in this allergen. At least one minor IgE-binding epitope still bound IgE after denaturation of the allergen. Removal of the high-mannose chains from denatured Art v II had no significant effect on the binding of human IgE to the minor IgE-binding epitope(s).     

Insect communities on experimental mugwort (Artemisia vulgaris L.) plots along an urban gradient

We studied the ability of insect herbivores and their natural enemies to colonize exposed, potted mugwort plants (Artemisia vulgaris L.) along a rural-urban gradient in 1994 in Hamburg (northern Germany). Ectophagous insects, leafmines and galls were monitored weekly from mid-May to mid-September. Endophagous insects were counted by harvesting and dissecting the stems at the end of the growing season. The rural-urban gradient was characterized by a gradient of vegetation-free areas and increasing proportion of ground covered in concrete, tarmac, paving and other impermeable surfaces surrounding the Artemisia plots, i.e. six different zones of increasing isolation. Numbers of insect species (herbivores, parasitoids and predators) decreased along the gradient from 43 to 12. Monophagous herbivores were not more affected than polyphagous herbivores, but parasitoids, especially rare species, were more strongly affected by isolation than predators. Some dominant herbivorous species were very successful colonizers and occurred in inner city sites devoid of all natural vegetation. Sometimes their abundance increased in the inner city to significantly higher densities than in the urban fringe. Isolation appeared to be the main reason for the observed patterns, since area and soil conditions were held constant in the experiment. Microclimate and pollution were considered to play a minor role. Received: 16 January 1997 / Accepted: 26 August 1997     

Variations in mugwort (Artemisia spp.) airborne pollen concentrations at three sites in central Croatia, in period from 2002 to 2003

In spite of the low atmospheric pollen levels, Artemisia sensitisation and allergy has been reported widely. The aim of the study was to determine the length of pollen season, intradiurnal, daily and monthly pollen variation, and the effect of some meteorological parameters on atmospheric pollen concentrations in Central Croatia. Seven-day Hirst volumetric pollen and spore traps were used for pollen sampling. The Artemisia pollen season lasted from the end of July until the end of September with the highest concentrations in August. The percentage of the total pollen count ranged from 0.52% to 0.92%. The intradiurnal peak occurred between 10 a.m. and 12 a.m. Statistical analysis showed a significant correlations between higher air temperature and high pollen concentration as well as high precipitation and low pollen concentration. Results of this study are expected to help in preventing the symptoms of allergic reaction in individuals with Artemisia pollen hypersensitivity.     

Ragweed and mugwort pollen in Szczecin, Poland

Ragweed (genus Ambrosia) and mugwort (Artemisia vulgaris) pollen grains are known to be very potent aeroallergens, often noted to enter into cross reactions. The aim of the study was to analyse ragweed and mugwort pollen release in Szczecin (western Poland) during the period 2000–2003. Measurements were performed by the volumetric and gravimetric method. Pollen seasons were defined as the periods of 90% of the total catch. Of the 4 years studied, the lowest concentration of ragweed pollen was observed in 2000. In 2000, the annual ragweed pollen count was very high, threefold higher than in 2001. There was a high Ambrosia pollen count in 2003, with the highest daily value of 84 grains/m³. The mugwort pollen season started in the third 10-day period of July and lasted to the end of August in all of the years studied. Analysis of pollen deposition from different Szczecin city’s districts showed that the highest exposure to ragweed pollen allergens occurred in the Majowe district, which is related to the presence of numerous plants of Ambrosia in that district. The mugwort pollen deposition was more abundant in the Żelechowa district, which is an area with villas and gardens. Statistically significant correlations were found between the ragweed pollen count in the air and the maximum wind speed, air temperature and relative humidity and between the mugwort pollen count in the air and air temperature and relative humidity.     

Molecular and immunological characterization of profilin from mugwort pollen

In late summer in Europe, pollen of mugwort is one of the major sources of atopic allergens. No information about the complete molecular structure of any mugwort allergen has been published so far. Here we report the isolation and characterization of mugwort pollen cDNA clones coding for two isoforms of the panallergen profilin. Thirty-six percent of the mugwort-allergic patients tested displayed IgE antibodies against natural and recombinant profilin, and no significant differences were observed in the IgE-binding properties of the isoforms. One profilin isoform was purified to homogeneity and detailed structural analysis indicated that the protein exists in solution as dimers and tetramers stabilized by sulfydryl and/or ionic interactions. Profilin monomers were detectable only after exposure of multimers to harsh denaturing conditions. Dimers and tetramers did not significantly differ in their ability to bind serum IgE from mugwort pollen-allergic patients. However, oligomeric forms might have a higher allergenic potential than monomers because larger molecules would have additional epitopes for IgE-mediated histamine release. Profilin isolated from mugwort pollen also formed multimers. Thus, oligomerization is not an artifact resulting from the recombinant production of the allergen. Inhibition experiments showed extensive IgE cross-reactivity of recombinant mugwort profilin and profilin from various pollen and food extracts.     

Quantification of Art v 1 and Act c 1 being major allergens of mugwort pollen and kiwi fruit extracts in mass-units by ion-exchange HPLC-UV method

A simple ion-exchange HPLC-UV method was developed for determination of major allergens from mugwort pollen and kiwi fruit extracts in mass-units. The separation of Art v 1 and Act c 1 from other components in the extracts was achieved in one step. The extinction coefficients used in the study were theoretically determined and compared to the extinction coefficients determined by gravimetry. We also reported a close correlation of the major allergen contents with the overall allergenic potency of the extracts determined by inhibition ELISA. This method could be a useful tool for standardization of allergenic extracts for clinical use.     

Chemical modification studies onCocos nucifera pollen allergens

Two highly active allergens C_n II (M _r 158,000) and C_nVII (M _r 2900) isolated fromCocos nucifera pollen extract were treated with various protein modifying reagents in order to ascertain the amino acid residues responsible for their allergenicity, In C_n II modification of carboxy group and tryptophan residue led to 30 and ≽ 75% loss in allergenicity and those of lysine and tyrosine reduced 62 and 38% activity, Lysine, tyrosine, tryptophan and carboxy group of C_nVII were also modified causing 81, 17, ≽ 70 and 26% loss of allergenicity respectively, Allergenicity of both was highly affected by pronase and moderately affected by heat, Periodate destroyed about 50% of their allergenicity and other chemical reagents except urea had no remarkable effect     

Comparison of the effects of Artemisia vulgaris and Artemisia absinthium growing in western Anatolia against trichinellosis (Trichinella spiralis) in rats

Trichinellosis often causing diarrhea and more rarely fever, periorbital edema and myositis in human, is commonly treated with benzimidazole derivatives. The Artemisia genus has been found to be effective against a variety of parasites. In the present study, the efficacy against trichinellosis (Trichinella spiralis) of Artemisia vulgaris and Artemisia absinthium was examined for the first time in rats. The results of trichinoscopy and artificial digestion, during the enteral (adult) phase of the illness show that 300 mg/kg doses of methanol extracts of the aerial parts of A. vulgaris and A. absinthium reduced the larval rate by 75.6% and 63.5% in tongue, 53.4% and 37.7% in diaphragm, 67.8% and 46.2% in quadriceps, and 66.7% and 60.5% in biceps-triceps muscles of rats, respectively. Furthermore, during the parenteral (encapsulated larvae) phase, 600 mg/kg doses of A. vulgaris and A. absinthium extracts decreased the larval rate by 66.4% and 59.9% in tongue, 57.4% and 50.0% in diaphragm, 47.6% and 43.7% in quadriceps, 60.2% and 46.4% in biceps-triceps muscles of rats, respectively. Analysis of antibody also showed that A. vulgaris significantly reduced the antibody response (P < 0.05) during the enteral and parenteral phases. Thus, the results of the present study revealed that A. vulgaris could be an alternative drug against trichinellosis.     

Transgenic ryegrasses (Lolium spp.) with down-regulation of main pollen allergens

Ryegrass pollen (Lolium species) is a widespread source of air-borne allergens and is a major cause of hayfever and seasonal allergic asthma, which affect approximately 25% of the population in cool temperate climates. The main allergens of ryegrass pollen are the proteins Lol p 1 and Lol p 2. These proteins belong to two major classes of grass pollen allergens to which over 90% of pollen-allergic patients are sensitive. The functional role in planta of these pollen allergen proteins remains largely unknown. Here we describe the generation and analysis of transgenic plants with reduced levels of the main ryegrass pollen allergens, Lol p 1 and Lol p 2 in the most important worldwide cultivated ryegrass species, L. perenne and L. multiflorum. These transgenic plants will allow the study of the functional role in planta of these pollen proteins and the determination of potential for development of hypo-allergenic ryegrass cultivars.     

Proximity-dependent pollen performance in Silene vulgaris

BACKGROUND AND AIMS: Pollen and seed dispersal in herbaceous insect-pollinated plants are often restricted, inducing strong population structure. To what extent this influences mating within and among patches is poorly understood. This study investigates the influence of population structure on pollen performance using controlled pollinations and genetic markers. METHODS: Population structure was investigated in a patchily distributed population of gynodioecious Silene vulgaris in Switzerland using polymorphic microsatellite markers. Experimental pollinations were performed on 21 hermaphrodite recipients using pollen donors at three spatial scales: (a) self-pollination; (b) within-patch cross-pollinations; and (c) between-patch cross-pollinations. Pollen performance was then compared with respect to crossing distance. KEY RESULTS: The population of S. vulgaris was characterized by a high degree of genetic sub-structure, with neighbouring plants more related to one another than to distant individuals. Inbreeding probably results from both selfing and biparental inbreeding. Pollen performance increased with distance between mates. Between-patch pollen performed significantly better than both self- and within-patch pollen donors. However, no significant difference was detected between self- and within-patch pollen donors. CONCLUSIONS: The results suggest that population structure in animal-pollinated plants is likely to influence mating patterns by favouring cross-pollinations between unrelated plants. However, the extent to which this mechanism could be effective as a pre-zygotic barrier preventing inbred mating depends on the patterns of pollinator foraging and their influence on pollen dispersal.     

A comparative biochemical study of conifer pollen allergens

In the order Coniferales, only the family Cupressaceae is regarded as being a significant source of airborne allergens, withJuniperus ashei characterized as the most significat aeroallergen. Pollen of the closely related speciesJ. virginiana has been shown to cross-react withJ. ashei pollen, however,J. virginiana pollen is not considered an important aeroallergen. Although there have been several reports of allergies toPinus pollen, the pollen of this genus is regarded as hypoallergenic. Our previous studies have shown that pollen extracts ofJ. ashei, J. virginiana, J. pinchotii, Cupressus macrocarpa, Pinus echinata andP. taeda all contained several proteins with the same molecular weights including the reported allergen ofJ. ashei. The present study compared the biochemistry ofJ. ashei, J. virginiana andP. echinata pollen. A time course experiment ofJ. ashei, J. virginiana andP. echinata showed thatJ. ashei released a greater quantity of protein within the first minute of moistening. SDS-PAGE analyses showed that the reported allergen ofJ. ashei pollen extracts was released in large quantities within the first minute of extraction. It was also determined that individual pollen grains ofP. echinata contained a greater quantity of protein than the pollen ofJ. ashei andJ. virginiana, but due to the large size of pine pollen there was less protein per gram of pollen. Lipid analysis of these three taxa showed that the pollen ofP. echinata contained more lipid per grain and per gram of pollen. Results indicate that the rapid release of the reported allergen fromJ. ashei pollen contributes to the allergenicity of this species compared to bothJ. virginiana andP. echinata.     

Seasonal changes of humoral and cellular immune responses to Japanese cedar (Cryptomeria japonica) pollen allergens in Japanese monkeys (Macaca fuscata) with pollinosis

The natural occurrence of Japanese cedar [Cryptomeria japonica (CJ)] pollinosis has been reported in Japanese monkeys (Macaca fuscata). The present study was designed to investigate seasonal changes in immunological reactions to CJ pollen allergens in monkeys with CJ pollinosis. Blood samples were collected from six monkeys with CJ pollinosis before and after CJ pollen season. Seasonal changes in specific IgE and IgG to major allergens (Cry j 1 and Cry j 2) were observed before and after CJ pollen season. The humoral responses decreased significantly before CJ pollen and increased after CJ pollen season. Similar seasonal changes in peripheral blood mononuclear cells proliferative responses to CJ allergens were observed before and after CJ pollen season. These humoral and cellular immune responses might serve as a biomarker for assessing new immunotherapies for monkeys with pollinosis.     

Feasibility study on automated recognition of allergenic pollen: grass, birch and mugwort

Quantification of airborne pollen is an important tool in scientific research and patient care in allergy. The currently available method relies on microscopic examination of pollen slides, performed by qualified researchers. Although highly reliable, the method is labor intensive and requires extensive training of the researchers involved. In an approach to develop alternative detection methods, we performed a feasibility study on the automated recognition of the allergenic relevant pollen, grass, birch, and mugwort, by utilizing digital image analysis and pattern recognition tools. Of a total of 254 pollen samples (including 79 of grass, 79 of birch and 96 of mugwort), 97.2% were recognized correctly. This encouraging result provides a promising prospect for future developments.     

Floret specialization, seed production and gender in Artemisia vulgaris L. (Asteraceae, Anthemideae)

Flowering and fruiting behaviour of female and hermaphrodite florets is described and assessed in samples from three populations from Denmark, England and Sweden. Between 25 and 50% of the florets in capitula are female, and flowering gender varies little among plants in each population. Fruiting gender of individuals, G (femaleness), varies from 0 to 0.85, because of variation in fruit set and fruit abortion. Variation in fruiting gender was correlated with plant size parameters in two populations, but not in the third. The data suggest that post-anthesis regulation of maternal investment may be operating. Florets of A. vulgaris are either totally specialized for pollen receipt (female florets) or largely specialized for pollen donation (hermaphrodite florets), and show adaptations for avoiding interference with each other in these functions. Movement of capitula from a pendent position at flowering to an erect position at fruiting optimizes positions for dissemination of pollen and of seeds respectively.     

Determination of birch pollen allergens in different aerosol sizes

Allergens in fine particles may cause symptoms inallergic asthmatics. In order to assess the exposureof susceptible persons, a method to measure theallergen load in fine and coarse particles wasdeveloped.Aerosols are collected with a high-volume air samplerby multistage impaction. They are separated into fivesize classes, ranging from >10 m to <1 mand sampled on glass fibre filters. After sampling,filters are crushed into a fine powder using ahydraulic press. Allergens are then eluted on a shakerinto Tween-20-containing phosphate buffered saline.After microfiltration, the eluate is ready foranalysis with ELISA-techniques (Enzyme Linked ImmunoSorbens Assay).Two different methods are used for the analysis ofallergens: One is a sandwich-ELISA using monoclonalIgG-antibodies, the other is a competitive ELISA basedon polyclonal IgE-antibodies obtained from patientsallergic to birch pollen. Using the monoclonalantibodies information on the amount of one particularallergen (the major allergen Bet v1) is obtained. Onthe other hand the competitive ELISA using thepolyclonal IgE is much more sensitive and indicatesthe total birch pollen allergens. Data obtained duringspring 1998 show good correlation of pollen counts andallergen content in the coarse particle fractioncontaining intact pollen (>10 m). In smallersized fractions, the allergen load is often close tothe detection limit. When clearly detectable amountsof allergen are present, in the fine size fraction theallergen load shows only a weak correlation to thepollen counts and the allergen concentrations in thecoarse particle fraction.