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PubMed1993

Monoclonal antibody immunoassay for quantitative analysis of group V allergens in grass pollen extracts.

A two-site monoclonal antibody (MoAb) ELISA has been developed for the quantification of the Phleum pratense major allergen, Phl p V. The assay is based on two MoAbs which recognize different non-overlapping epitopes on the Phl p V molecule; one antibody (1D11) was immobilized on the solid phase and the other (3B2) was biotinylated. An affinity-purified Phl p V preparation (purity of 95%) was used as standard. The assay has a sensitivity of 10 ng/ml of allergen and is suitable for the detection of group V allergen in aqueous grass extracts. The specificity of the assay was investigated with 14 grass pollen and five non-grass pollen extracts. Different levels of group V allergen were detected in extracts of grasses, but not in non-grasses. The assay gives a good correspondence with allergenic activity of extracts as determined by ELISA inhibition using serum pool of allergic patients. The results indicate that the two-site MoAb ELISA could be very useful in the standardization of allergenic extracts from grass pollen.

Allergens↗
PubMed1996

Detection of allergen-specific IgE in tears of grass pollen-allergic patients with allergic rhinoconjunctivitis.

BACKGROUND: Allergic conjunctivitis is a common symptom amongst Type I (IgE-mediated) allergic diseases; and most frequently seen as rhinoconjunctivitis. However, the site of production and the significance of allergen specific IgE needs further elucidation. OBJECTIVE: We investigated whether the presence of IgE in tears of grass pollen allergic patients correlated with disease and clinical symptoms, whether the IgE binding pattern to the different grass pollen antigens was different in sera and tears, and whether IgA antibodies to grass pollen allergens were present in tears. Finally, we looked whether specific IgE was produced locally or was exudated from serum. METHODS: Sera from 44 grass pollen allergic patients suffering from either allergic rhinitis (n = 11) or allergic rhinoconjunctivitis (n = 33) and from healthy controls (n = 7) were used for the experiments. Binding of specific IgE and IgA antibodies to the different groups of grass pollen allergens (Phleum pratense) was evaluated by means of immunoblotting. RESULTS: Specific IgE was detected in sera as well as in tears of allergic patients, whereby tear-derived allergen-specific IgE exerted similar specificities to the corresponding IgE from serum. The correlation between symptoms of ocular allergy and the presence of allergen-specific IgE in tears was highly significant (P < 0.0001). In contrast, only a poor correlation was found between specific and/or total IgE in sera and the manifestation of ocular allergy (P = 0.73). CONCLUSION: Allergen-specific IgE antibodies in tears seem to be produced locally rather than exudated from serum. IgE in tears seems to be responsible for allergic conjunctivitis. IgA in tears cannot exert a protective function since the IgA antibodies recognize different antigens in a grass pollen (Phleum pratense) extract than IgE antibodies. The highly significant correlation between allergic conjunctivitis and the presence of specific tear IgE emphasizes the diagnostic value of immunoblots with tear IgE, especially in cases in which serum provides inconclusive results.

Allergens↗
PubMed1995

The relationship between ecophysiology, indigenous microflora and growth of Listeria monocytogenes in grass silage.

The combined effect of the physical and chemical parameters (oxygen tension, pH and dry matter) influencing Listeria monocytogenes growth and survival in silage were simultaneously studied in a model in vitro system. Ensiled grass was exposed to a range of low oxygen concentrations, 0-5% v/v, and their effect was recorded with respect to acidification and microbial population dynamics of the epiphytic microflora, i.e. lactic acid bacteria, enterobacteria, yeasts, moulds and L. monocytogenes in grasses pre-inoculated with the latter. Listeria monocytogenes survival depended on the establishment of a fine balance between the physico-chemical and microbiological characteristics, i.e. oxygen tension, dry matter, pH, grass and microbiological quality. In all grasses ensiled, an oxygen concentration of 1.0% or greater sustained L. monocytogenes growth, below this level growth was shown to be principally dependent on the rate and quality of the fermentation. In most grasses 0.5% oxygen prolonged survival, whereas 0.1% and 0% oxygen caused L. monocytogenes to die off. In very poor quality grass with a restricted fermentation L. monocytogenes survival was prolonged even under anaerobic conditions.

Anaerobiosis↗
PubMed1988

Sensitivity to tomato and peanut allergens in children monosensitized to grass pollen.

Possible associations between allergy to grass pollen and positive skin tests to food allergens were studied in 102 children monosensitized (as to inhalant allergens) to grass pollen, and in 117 children monosensitized (as to inhalant allergens) to Dermatophagoides. Thirty-two foods were tested by an epicutaneous method. Positive skin tests to food allergens were more frequent in children with allergy to grass pollen (59.8%) than in children with allergy to Dermatophagoides (9.4%). A considerably high frequency of positive reactions to tomato (39.2%), peanut (22,5%), green pea (13.7%), and wheat (11.7%) was observed in children with allergy to grass pollen. Positive skin tests to peanut closely correlated with positive RAST results and nasal provocation tests, whereas in children with skin test positivity to tomato a close correlation with nasal provocation tests but a 45% correlation with a positive RAST result were observed. RAST inhibition experiments were carried out, and the results may suggest the presence of cross-reacting IgE to grass pollen, tomato, and peanut antigens. Clinical implications of these findings are discussed in the light of histories of food hypersensitivity, urticaria-angioedema, and atopic dermatitis in children with allergy to grass pollen.

Adolescent↗
PubMed2004

The co-seasonal application of anti-IgE after preseasonal specific immunotherapy decreases ocular and nasal symptom scores and rescue medication use in grass pollen allergic children.

BACKGROUND: Specific immunotherapy (SIT) and treatment with anti-immunoglobulin (Ig)E antibody are complementary approaches to treat allergic rhinoconjunctivitis, which may be used for single or combined treatment. OBJECTIVE: A randomized, double-blind, placebo-controlled trial was conducted to compare the efficacy of single and combined treatment with SIT and anti-IgE (Omalizumab) in reducing symptom severity and rescue medication use. METHODS: A total of 221 subjects with birch and grass pollen allergic rhinoconjunctivitis aged 6-17 years were analysed during the grass pollen season. Group A (SITbirch + placebo) served as a reference group obtaining no effective treatment for grass pollen allergy. Group B received anti-IgE monotherapy during grass pollen season, group C SIT grass pollen monotherapy, and group D the combined treatment of SIT and Omalizumab. RESULTS: Preseasonal treatment with grass pollen SIT alone compared with SIT with the nonrelated allergen did not reduce symptoms or rescue medication use. Anti-IgE monotherapy significantly diminished rescue medication use and number of symptomatic days. The combined treatment with SIT and anti-IgE showed superior efficacy on symptom severity compared with anti-IgE alone. CONCLUSIONS: Co-seasonal Omalizumab therapy showed considerable effects in children with seasonal allergic rhinitis. The combination of SIT plus Omalizumab was clinically superior to each treatment alone during the first year of observation.

Adolescent↗
PubMed2006

Safety of a SQ-standardised grass allergen tablet for sublingual immunotherapy: a randomized, placebo-controlled trial.

BACKGROUND: Sublingual treatment of grass pollen induced rhinoconjunctivitis might provide easier access to specific immunotherapy (SIT) and minimize the risk of serious adverse events (AEs) compared to subcutaneous SIT. AIM OF THE STUDY: To identify a safe dose range for once-daily administration of a grass allergen tablet in participants with grass pollen induced seasonal rhinoconjunctivitis. METHODS: A randomized, double blind, placebo-controlled Phase I trial was conducted outside the grass pollen season. Seven dosage groups [25,000, 75,000, 150,000, 300,000, 500,000, 750,000, or 1,000,000 standardized quality tablet (SQ-T)], consisting of 12 participants randomized either to active treatment or placebo (3 : 1) daily for 28 days, commenced treatment in a staggered manner at intervals of approximately 1 week to allow for intermittent safety reviews. RESULTS: The grass allergen tablet did not cause any serious, systemic or significant (leading to withdrawal) AEs. The overall incidence of AEs was 74% (1,013 events); all of mild or moderate intensity and most considered treatment-related. The most frequently reported treatment-related AEs, including irritation of the throat, and itching sensations in the mouth and ears, increased with dose. These were primarily mild in intensity, started shortly after medication intake and lasted for minutes to a few hours maximum. Objective oral findings were also dose-dependent. No clinically significant observations were found in safety laboratory, vital signs and 12-lead ECG. CONCLUSIONS: A sublingual grass allergen tablet in doses up to 1,000,000 SQ-T daily caused no serious or systemic AEs displaying a safety profile that allows further investigation as once-daily self-medication.

Administration, Sublingual↗
PubMed2006

The effects of grass pollen allergoid immunotherapy on clinical and immunological parameters in children with allergic rhinitis.

Allergoid immunotherapy is a new form of allergen immunotherapy allowing safe administration of high allergen doses. There is limited information on the effects of allergoid immunotherapy in children with allergic rhinitis. To investigate the immunological and clinical effects of allergoid immunotherapy in children with allergic rhinitis due to grass pollen allergy. Children with allergic rhinitis were assigned to allergoid immunotherapy (n = 27) or control (n = 26, no immunotherapy) groups. Children in the immunotherapy group received seven injections of grass pollen allergoid immunotherapy before grass pollen season and continued to receive maintenance immunotherapy for 27 months. All patients were offered a pharmacotherapy regimen to be used on demand during the pollen seasons. Clinical and laboratory parameters were compared between the immunotherapy and control groups. The rhinoconjunctivitis symptom-medication score and asthma symptom score were lower in the immunotherapy group after 1 yr of maintenance immunotherapy (p < 0.01 for both). Skin test reactivity and nasal reactivity as determined by nasal provocation testing for grass pollen were significantly decreased after 1 yr of immunotherapy (p < 0.001 for both). The seasonal increase in bronchial reactivity and nasal lavage eosinophil cationic protein levels were prevented after the first year of immunotherapy (p < 0.05 for both). The seasonal increase in immunoglobulin (Ig)E decreased (p < 0.05) and grass-specific IgG, IgG(1) and IgG(4) increased significantly already at the end of the seven-injection build-up therapy (p < 0.001, for all). Interleukin (IL)-4 levels in the culture supernatants showed a steady decline from baseline at first and second year of immunotherapy (p < 0.001) but remained unchanged in the control group. Allergoid immunotherapy is an effective method in the treatment of grass pollen-induced allergic rhinitis in children and prevents the seasonal increase in bronchial hyper-reactivity. Changes in specific IgE and IgG levels and decreased IL-4 production in peripheral blood mononuclear cell culture supernatants may account for the observed clinical effects.

Adolescent↗
PubMedDate not supplied

Ultrasonographic features of grass awn migration in the dog.

The aim of this study was to describe the ultrasonographic features of grass awns in soft tissue. A 10 MHz linear transducer was used. Ultrasound images from 25 dogs (27 awns) were collected and compared with the results from water bath studies using wild oat seeds (Avena spp.) collected in the field. Wild oat seeds were the most common grass awn found in soft tissue of dogs. Ultrasonographically grass awns appeared as a double/triple spindle-shaped echogenic interface within soft tissue. The same appearance was observed in water bath studies. In four dogs, the grass awn was removed surgically with a clamp introduced into a fistulous tract, using sonographic guidance. The grass awn was not found surgically in only three dogs, suggesting more attention during surgery. Ultrasonography is a useful diagnostic imaging technique to identify grass awns within soft tissue.

Animals↗
PubMed1991

Clinical and biochemical features of grass sickness (equine dysautonomia).

An attempt has been made to assess the diagnostic value of clinical features seen at initial examination of horses with grass sickness, colic cases and cases submitted as possible grass sickness but diagnosed subsequently as some other condition. There appears to be no single pathognomonic sign for grass sickness. A range of signs has been associated with grass sickness but these are of value only when related to the length of illness and the history. Biochemical tests related to intestinal tissue damage, stress and dehydration were evaluated and most were found to be of value in diagnosing acute grass sickness. No evidence was found relating selected mineral or vitamin deficiencies to grass sickness, nor were protein changes specific. A marked fall in glutathione peroxidase values was associated with grazing rather than disease.

Alkaline Phosphatase↗
PubMed1991

A comparative study of normal equine populations and those with grass sickness (dysautonomia) in eastern Scotland.

A retrospective survey was made of premises in eastern Scotland on which at least two cases of grass sickness had occurred between 1970 and 1987. For comparison, a further survey of 49 equine establishments, on which no grass sickness had been recorded, was conducted from 1986 to 1988. The results indicated that younger animals are more susceptible, especially those in good physical condition grazing full-time in the spring or early summer. Movement to new grazing increases the risk of grass sickness and identifiable stress may contribute. The nature of the establishment governed the animals' condition during the summer, but it did not appear to influence the prevalence of grass sickness. However, riding schools and livery establishments which experienced the disease kept, on average, significantly more animals than unaffected premises of the same type. No relationship was found between supplementary feeding or stage of pasture growth and grass sickness. The results of the survey support the hypothesis that the causal agent of grass sickness is associated with grazing but multiple factors may influence the expression of illness.

Age Factors↗
PubMed2002

Oligoclonal analysis of the atopic T cell response to the group 1 allergen of Cynodon dactylon (bermuda grass) pollen: pre- and post-allergen-specific immunotherapy.

BACKGROUND: Bermuda grass pollen (BGP) is an increasingly important seasonal aeroallergen in Australia and other subtropical and temperate regions. BGP shares minimal allergenic cross-reactivity with pollens of rye grass or other Pooideae grasses often used for desensitization regimens in grass pollen allergy. Current allergen immunotherapy is seldom used in asthmatic patients due to IgE-mediated side effects. Since clinically effective immunotherapy is linked with altered allergen-specific T cell response, characterisation of human T cell reactivity to Cyn d 1, the major B cell allergen of BGP, should permit the design of effective and safe immunotherapy for BGP allergy. METHODS: Short-term BGP-specific CD4+ T cell lines were established from peripheral blood of 14 BGP-sensitive patients before and after conventional 50% BGP and 50% 7-grass mix subcutaneous specific allergen immunotherapy (SIT). T cell diversity of antigen specificity and function was assessed by proliferation and cytokine production to BGP, Cyn d 1 and Cyn d 1 peptides. RESULTS: Three highly immunogenic regions of Cyn d 1 were identified in 13/14 patients pre-SIT: Cyn d 1 (109-128), (181-209) and (217-241). The SIT regimen was clinically efficacious. Following SIT, decreased proliferation to BGP, Cyn d 1 and Cyn d 1 peptides was observed with a marked decrease in the IL-5:IFN-gamma ratio. CONCLUSIONS: Cyn d 1 is a major T cell allergen of BGP. Decreased Cyn d 1-specific IL-5 dominant T cell responses were observed in association with clinically effective treatment with the 50% BGP and 50% 7-grass mix. Identified dominant T cell regions of Cyn d 1 should facilitate safer vaccine development for BGP-induced asthma in addition to rhinitis.

Adult↗
PubMed1978

Cross-reactivity between grass and corn pollen antigens.

Analogous reactions of grass and corn pollen extracts in skin tests on patients suffering from pollinosis might suggest an antigenic relationship between grass and corn pollens. This problem was studied using the RAST inhibition test. Tests were performed with cellulose discs labelled with commercial skin test extracts containing grass, rye, wheat, barley, oat and maize pollens. Different mutual inhibitions were measured showing various grades of antigenic relationship. Only grass pollen antigens could strongly inhibit all other antigen-antibody reactions. Thus, we suppose that the investigated grass pollen extract also contains all antigens typical of corn pollen. Therefore, exclusive use of this extract seems to be possible in diagnosis and perhaps therapy of combined grass and corn pollen allergy.

Cross Reactions↗
PubMed1989

Demonstration of human, rye grass pollen extract-specific, helper and suppressor stimulating activity of modified allergens by effects on in vitro hapten-specific antibody production.

An in vivo system is described in which penicilloyl antibody was produced from peripheral leucocytes of a grass pollen-sensitive patient who had received penicillin therapy, by challenge of the cells with penicilloyl-grass pollen extract conjugate. Incubation of these leucocytes with a number of modified preparations of grass pollen extract with various T-cell-stimulating properties was shown to affect penicilloyl antibody production. Both chymotryptically fragmented rye grass pollen extract and a conjugate of f met-leu-phe and rye grass pollen extract enhanced penicilloyl-specific antibody similarly to the enhancement induced by unmodified extract, though at high concentration some suppression was seen. A conjugate of polysarcosine and rye grass pollen extract, previously shown to cause antibody suppression in mice, was similarly suppressive for penicilloyl-specific antibody. The system therefore shows potential for the evaluation of the effects of modified allergen treatment on antibody levels via T-cell mechanisms.

Allergens↗
PubMed1992

Grass aeropollen of the western United States Gulf Coast.

Volumetric air sampling was performed at Corpus Christi, Tex., September 1987 to August 1989. Grass aeropollen during all of 1988 accounted for 15.3% of total pollen captured during two major peaks, one in May and another during September and October. The remaining grass pollen, about one-quarter of the total, was found throughout the year with low levels in the winter and mid-summer. This bimodal pollen release corresponds to the flowering of two major types of grasses occurring in the western Gulf Coast region, the cool temperate species which are predominantly spring flowering in response to long-day photoperiodicity, and the more common warm temperate and subtropical species flowering by and large in the fall as short-day plants. Supplementing the already rich grass flora and adding to the high proportion of total aeropollen was the long distance dispersal of grass pollen found perhaps in sufficiently high quantities to trigger allergic symptoms and to cause grass pollinosis out of season, at least in acutely sensitive individuals. This occurred in late March, well before the spring peak in May. Correlations existed between near-drought conditions and reduced pollen shed in 1988, and normal precipitation and much higher pollen shed during parts of 1987 and 1989, illustrating the importance of environmental factors such as moisture on annual pollen frequency and level of pollinosis which can be variable and annually unpredictable. What is predictable is the genetically controlled timing of pollen maturation and release which will be generally the same year by year.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants↗
PubMed1996

Identification and characterization of the major allergens of velvet grass (Holcus lanatus), Hol l 1 and Hol l 5.

Although extract of velvet grass pollen is an important ingredient of commercial allergen extracts for immunotherapy, it is not defined concerning its major allergenic components. We have investigated the extract of velvet grass pollen by Western blotting using the sera of 97 patients and identified two major allergens of 34 and 30 kD. By two-dimensional immunoblotting with monoclonal antibodies and lectins, and by biochemical analysis the 34-kD protein was identified as a group I grass pollen allergen and the 30-kD protein as a group V grass pollen allergen. According to the nomenclature for grass pollen allergens we designated these allergens Hol l 1 and Hol l 5, respectively. Fragmentation of the velvet grass pollen extract by CNBr provided the first information on the localization of IgE binding epitopes on these two allergens. With Hol l 1 and Hol l 5 we identified two important components of commercial allergen extracts.

Allergens↗
PubMed2006

Sox genes in grass carp (Ctenopharyngodon idella) with their implications for genome duplication and evolution.

The Sox gene family is found in a broad range of animal taxa and encodes important gene regulatory proteins involved in a variety of developmental processes. We have obtained clones representing the HMG boxes of twelve Sox genes from grass carp (Ctenopharyngodon idella), one of the four major domestic carps in China. The cloned Sox genes belong to group B1, B2 and C. Our analyses show that whereas the human genome contains a single copy of Sox4, Sox11 and Sox14, each of these genes has two co-orthologs in grass carp, and the duplication of Sox4 and Sox11 occurred before the divergence of grass carp and zebrafish, which support the "fish-specific whole-genome duplication" theory. An estimation for the origin of grass carp based on the molecular clock using Sox1, Sox3 and Sox11 genes as markers indicates that grass carp (subfamily Leuciscinae) and zebrafish (subfamily Danioninae) diverged approximately 60 million years ago. The potential uses of Sox genes as markers in revealing the evolutionary history of grass carp are discussed.

Animals↗
PubMed1995

Toxic endophyte-infected tall fescue and range grasses: historic perspectives.

A historic profile of endophyte-induced tall fescue toxicosis is presented. A chronology of events is presented, beginning with the importance of finding Balansia-infected grasses in a tall fescue pasture in north central Georgia. This initial finding was followed by the discovery that another related endophyte was present in tall fescue and other major forage grasses. This species of endophyte was identified as Acremonium coenophialum. After this report was the important discovery that cattle performance was poor on Acremonium-infected tall fescue. Thus, this endophyte and its presence in tall fescue was implicated as the cause of tall fescue toxicosis and fescue foot. It was later established that this endophyte also produced ergot alkaloids. The related endophyte of perennial ryegrass, A. lolii, was subsequently shown to be responsible for the ryegrass staggers syndrome. Several other species of Acremonium have been associated with other important forage and turf grasses. Finally, important papers leading to the revelations that endophytic fungi and their grass hosts are ecologically significant and that most should be considered mutualistic symbioses are reviewed. Symbiotic grasses have enhanced physiological and morphological characteristics that offer biotechnological exploitations on one hand, but on the other solutions to the toxicity of tall fescue are difficult because grasses free of their fungal partner are generally ecological failures.

Acremonium↗
PubMed1993

Intestinal digestibility in dairy cows of protein from grass and clover measured with mobile nylon bag and other methods.

Ruminal, intestinal, and total tract digestibilities of CP in grass, grass silage, and clover were measured using the mobile nylon bag method. Total tract indigestibilities measured with this method were compared with indigestible CP predicted by in vitro, 14-d ruminal incubation, and 12-h followed by 14-d ruminal incubation methods. Indigestible CP was related to chemical composition and harvest date. Ruminal disappearance of CP from nylon bags was 58, 71, and 58% for grass, grass silage, and clover, respectively. Intestinal CP disappearance was 84, 81, and 91% of escape CP, respectively. Lower ruminal disappearance was compensated by higher intestinal disappearance, resulting in a small variation in total tract indigestible CP within forage. Total tract indigestible CP was 7, 6, and 4%, respectively. Average total tract indigestible CP measured with the mobile nylon bag method (6%) was lower than that estimated by the in vitro (13%), 14-d ruminal incubation (14%), or 12-h ruminal incubation followed by 14-d ruminal incubation (11%) methods. All methods ranked forages similarly, resulting in high correlation coefficients among methods within forage. Total tract indigestible CP of grass, grass silage, and clover was related to CP content and harvest date, DM and ADIN content, and DM and CP contents, respectively.

Animal Feed↗