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Background: Grass pollen is a major cause of allergy throughout the world. The only treatment targeting the causes and not only the symptoms of allergy is specific immunotherapy (IT). A number of controlled trials demonstrated the efficacy of IT in grass pollen allergic subjects, most using extracts of multiple grasses but some using extracts of a single grass. The optimal grass extract for IT has not yet been established. Methods: This study is aimed at investigating the IgE-binding pattern in sera from IT-naïve patients from central Italy with allergic rhinitis and/or asthma caused by grass pollen. A 5-grass extract was used (containing Dactylis glomerata, Poa pratensis, Lolium perenne, Antoxanthum odoratum and Phleum pratense) and compared to Phleum pratense alone, which is the most frequently used single grass extract, by the RAST-inhibition technique. Results: The 5-grass extract showed, by RAST-inhibition, a significantly higher binding compared to the Phleum pratense extract for Antoxanthum odoratum and Poa pratensis, while the two extracts for immunotherapy showed similar binding affinity for Phleum pratense and the non- Pooideae grass, Cynodon dactylon. Conclusions: The use of a mixed-grass pollen extract seems to be the optimal choice when applying specific IT in grass pollen-allergic subjects from the Mediterranean area. [ABSTRACT FROM AUTHOR]

Parallel follow-up of clinical and inflammatory markers during sub-lingual immunotherapy (SLIT) is highly beneficial. Twenty-four children (age 4–16) monosensitized to house dust mite were randomized to receive either active or placebo SLIT for 1 yr in a double-blind placebo controlled design (Marcucci et al., Allergy 2003: 58: 657–62). Thereafter, for 2 yr they all received active treatment. Symptom scores for rhinitis, asthma, and drug usage were daily recorded. Eosinophil cationic proten (ECP) and tryptase in sputum and nasal secretions, serum and nasal mite-specific immunoglobulin E (IgE) were recorded before treatment and at 10–12 months intervals. Nasal ECP and nasal tryptase after specific nasal provocation tests were significantly reduced as compared to baseline values (p = 0.0043 and 0.0195, respectively) in the third year of active treatment. None of the other inflammatory parameters was increased. In placebo treated patients all these parameters tended to decrease only after switching to active treatment. Clinical scores did not improve in treated vs. placebo patients in the double-blind placebo-controlled phase of the study. In both cohorts a clinical benefit was observed as intra-group score reduction as compared to baseline. A significant difference was reached in patients treated for 2 yr for rhinitis and asthma (p = 0.0009 and 0.0019, respectively) but not for drug usage and in patients treated for 3 yr for rhinitis, asthma, and drug usage (p = 0.0105, 0.0048, and 0.02, respectively). SLIT in children monosensitized to mites reverted the spontaneous increase in nasal IgE and in local parameters of allergic inflammation. These outcomes were followed by a consolidated clinical improvement in the second and third year of treatment. [ABSTRACT FROM AUTHOR]

Sublingual-swallow immunotherapy (SLIT) is an accepted treatment for allergic rhinitis but its optimal dosage is scantly investigated. We studied the dose dependence of clinical efficacy and immunological response to SLIT by administering two different dosages of the same allergen in rhinitic children monosensitized to grass pollen.Seventy-one patients with comparable age and symptoms were randomized to receive SLIT by the same grass pollen extract from Stallergénes (Antony, France), 40 of them with the 100 IR and 31 with the 300 IR extract. All patients recorded diary cards for symptoms, medications and side-effects of the treatment, and had measurements of specific IgE and IgG4 in serum by the CAP System FEIA (Pharmacia, Uppsala, Sweden) and in nasal secretion by anin situincubation method with the same reagents of CAP System FEIA.Symptom/medication scores during the pollen season were significantly higher in patients treated with the lower dosage compared with those treated with the 300 IR dosage. Side-effects occurred with a comparable rate (25.8%vs27.5%) in the two groups. Serum-specific IgE and IgG4 had no significant changes after 3 months of SLIT in both groups, while a significant seasonal increase of nasal IgE (P = 0.015) and IgG4 (P = 0.019) was found only in patients treated with the lower dosage.A rise of specific IgG4 and a blunting of seasonal increase of specific IgE in serum was repeatedly reported during subcutaneous immunotherapy (SCIT) with pollen extracts. Our findings show such blunting of specific nasal IgE along with a low symptom/medication score in patients treated with SLIT with the higher dosage, but not a concomitant rise of specific nasal IgG4. This suggests a local immunological effect of SLIT, different from systemic mechanisms of SCIT. [ABSTRACT FROM AUTHOR]

As the main target of sublingual immunotherapy (SLIT) is to reduce at most the occurrence of adverse events (AE), safety represents a critical issue. This aspect deserves particular mention when a higher dose of allergen extract than traditional subcutaneous immunotherapy (SCIT) is required to be effective: that may be up to 500 times that employed for SCIT.All published controlled studies concerning SLIT-swallow were analysed to evaluate AE rates.Studies were subdivided in two groups: (i) studies using low allergen dose (LAD), i.e. ranging from 1 to 50 times the dose commonly administered with SCIT, and (ii) studies with high allergen dose (HAD), i.e. ranging from 50 to 500 times the dose administered with SCIT.Twenty-five studies were altogether analysed: 13 studies belonged to the low-dose group, 12 belonged to the high-dose group. We considered all patients with at least one AE. Local reactions were significantly more frequent in the LAD group than in the HAD group (P<0.0001), while there was no difference in the rate of systemic reactions. Severe systemic reactions were never reported.This study represents the first analysis of the safety of SLIT concerning the allergen dose employed in the treatment. There is evidence that AE occurrence is substantially not dose-dependent. This fact highlights two main clinical aspects: the elevated tolerability of SLIT in general and the safety of HAD regimen. [ABSTRACT FROM AUTHOR]

Summary Background Subcutaneous immunotherapy for respiratory allergy has shown a long-lasting efficacy after its discontinuation, whereas this evidence is still lacking for sublingual immunotherapy, despite the fact that it is widely used. Objective We aimed to evaluate whether a long-lasting effect of SLIT occurs, in a prospective parallel group controlled study. Methods Sixty children (mean age 8.5 years) suffering from allergic asthma/rhinitis due to mites were subdivided into two matched groups: 35 underwent a 4- to 5-year course of SLIT with standardized extract and 25 received only drug therapy. The patients were evaluated at three time points (baseline, end of SLIT and 4 to 5 years after SLIT discontinuation) regarding presence of asthma, use of anti-asthma drugs, skin prick tests and specific IgE. Results We found that in the SLIT group there was a significant difference vs. baseline for the presence of asthma (P ≤ 0.001) and the use of asthma medications (P ≤ 0.01), whereas no difference was observed in the control group. The mean peak expiratory flow result was significantly higher in the active group than in the control group after 10 years. No change was seen as far as new sensitizations were concerned. Specific IgE showed a near-significant increase (baseline vs. 10 years, P = 0.06) only in the control group. Conclusion Our study demonstrates that sublingual immunotherapy is effective in children and that it maintains the clinical efficacy for 4 to 5 years after discontinuation. [ABSTRACT FROM AUTHOR]

Background: The clinical safety of sublingual immunotherapy (SLIT) has been repeatedly confirmed; nevertheless, the possible onset of local oral symptoms is still a concern, and nothing is known about the pathogenesis of this effect. We aimed to determine whether the administration of SLIT in allergic children can evoke an IgE-mediated reaction, by measuring the levels of sublingual tryptase and ECP. Methods: Thirty children (7–12 years old) with allergic rhinitis/asthma due to grass pollen were prescribed SLIT. In these children, an allergen-specific nasal challenge was performed, and nasal tryptase and ECP were measured before and after. Sublingual ECP and tryptase were also assessed before the SLIT, after 1 month, and after 6 months of treatment. Ten matched allergic children and 10 healthy ones served as controls for the baseline levels of sublingual ECP and tryptase. Results: The levels of nasal tryptase and ECP significantly increased after nasal challenge (P<0.001), whereas no change during the SLIT course (at the beginning, after 1 month, and after 6 months) could be detected in sublingual tryptase either before or after SLIT administration. The sublingual ECP significantly decreased after 6 months of SLIT. The baseline levels of nasal tryptase and ECP were significantly higher in allergic subjects than in healthy controls, as was the level of sublingual ECP. Conclusions: In the presence of an IgE-mediated reaction (ASNC), a significant increase of tryptase and ECP can be seen. When SLIT is administered, such a phenomenon does not occur; therefore, SLIT does not elicit any IgE reaction in the mouth. It is noteworthy that allergic subjects display higher levels of nasal ECP and tryptase than healthy subjects, even when symptom-free, and these observations may indicate the presence of subclinical inflammation. [ABSTRACT FROM AUTHOR]

Background: We assessed the efficacy of preseasonal local allergoid immunotherapy in a group of children with asthma and/or rhinitis and/or rhinoconjunctivitis due to grass pollen. Methods: We randomly assigned 24 children allergic to grass pollen to receivelocal allergoid immunotherapy for 3 months before the pollen season and 24 such patients to receive identically appearing placebo. The immunotherapy consisted of tablets of monomeric allergoid grass pollen allergens held in the mouth until they dissolved and then swallowed. The study was double-blind. Symptoms and medications were scored on diary cards during the pollen season. Nasal eosinophil cationic protein levels were measured by the monoclonal antibodies EG1 and EG2 outside the pollen season and at low and at high pollen concentration during the pollen season. Results: The active-treatment group had a statistically significant reduction of total symptoms (P<0.05), especially bronchial symptoms (P<0.05), in comparison with the placebo group. Immunotherapy was well tolerated and compliance was good. Nasal levels of EG2 and EG1 increased significantly during the pollen season, but there was no difference between groups. EG2/EG1 increased significantly only in the placebo group during natural allergen exposure (P<0.01). Conclusions: Our results suggest that this immunotherapy is effective for the treatment of asthma due to grass pollen in children. [ABSTRACT FROM AUTHOR]

The article offers a bioptic study on oral reactions to sublingual immunotherapy (SLIT). It is stated that although sublingual immunotherapy (SLIT) is currently considered a feasible option to traditional subcutaneous immunotherapy (SCIT) for treating allergic rhinitis caused by sensitization to seasonal or perennial allergens with a significant advantage in terms of safety, but mast cells and eosinophils are not the elicitors of local reactions to SLIT.

Presents information on a study featured in the 2002 issue of "Allergy," which assessed the safety and clinical efficacy of low-dose nasal immunotherapy in children with dust mite allergy. Study population; Clinical symptoms; Results of the nasal provocation test.