Allergenic Profile to <i>Phleum pratense</i> and Immunological Changes Induced after Grass Allergen-Specific Immunotherapy

Abstract

Background: The introduction of molecular diagnoses has provided evidence of the existence of several different allergenic profiles in grass-sensitised individuals, reflecting the large number of allergens involved. This methodology has become a potent tool for a correct diagnosis and for the selection of the most appropriate immunotherapy. Based on these concepts, the objectives of this study were to determine the sensitisation profile of a grass-allergic population, and to treat them with specific immunotherapy. Methods: Patients suffering from rhinitis and/or asthma associated with grass pollen were recruited. The active group was treated with depigmented-polymerised allergenic extract of mixed grass pollen. sIgE and sIgG4 to Phleum pratense, and to its individual components (Phl p 1, 2, 4, 5b, 6, 7, 11 and 12) were determined at the beginning and end of the study. Results: The inclusion criteria were fulfilled by 139 individuals (36 in the control group and 103 in the active group). Phl p 1 (96.4%) and Phl p 4 (91.2%) were the most recognised allergens, and 15.3% of individuals had positive IgE to cross-reactive carbohydrate determinants. Levels of antigen-specific IgG4 increased significantly after treatment, and the IgE/IgG4 ratio decreased significantly in all allergens after receiving allergen-specific immunotherapy. Non-significant differences were observed in the control group. Conclusions: A high percentage of sensitisation to Phl p 4 was observed. Immunological efficacy was studied by measuring sIgG4 levels and the IgE/IgG4 ratio before and after treatment. Sensitisation profiles should be taken into consideration to prepare the most appropriate immunotherapy containing all the relevant and needed allergens.

Sensitization to grass pollen allergen molecules in a birth cohort—natural Phl p 4 as an early indicator of grass pollen allergy

“…In line with previous studies, Phl p 1 was the most prevalent sensitizing molecule in our population, 2,8,11,[22][23][24][25] but a high proportion also had IgE reactivity to nPhl p 4. In its natural glycosylated form, this allergen molecule has been classified as a major allergen in both children 12,13,21,26 and adults according to frequency of IgE recognition, 2,22,27,28 but IgE reactivity to recombinant rPhl p 4 is seen much less frequently. 11 The clinical value of sensitization to nPhl p 4 has been questioned because nPhl p 4 contains CCDs 2,3 and has been shown to have much lower allergenic activity compared with Phl p 1, Phl p 2, and Phl p 5.…”

Pretreatment IgE sensitization patterns determine the molecular profile of the IgG4 response during updosing of subcutaneous immunotherapy with timothy grass pollen extract

“…However, the prevalence of component-specific sensitizations was comparable with those reported at http:// www.allergen.org. Compared with a study in 101 patients with grass pollen allergy from Germany 23 and a Spanish study including 139 patients with grass allergy, 24 we found a higher level of Phl p 5-specific IgE and a lower level of Phl p 4-specific IgE, which might be explained by regional differences in exposure patterns. We did not find a relation between disease duration and sensitization pattern (data not shown) described in a recent pediatric study.…”

Patterns of sensitization to inhalant and food allergens among pediatric patients from the Moscow region (Russian Federation)

“…Currently, there are a number of studies describing the immunological profiles of sIgE [ 9 , 10 ] and sIgG4 [ 11 ], especially in relation to recombinant allergens, among patients with different pathologies in various geographical locations. However, Central Russia has been investigated less in the aforementioned studies.…”