Expression of allergen mimotopes as fusion proteins linked to the albumin binding protein (ABP) of streptococcal protein G and their immunological properties

The aim of this prospective and longitudinal birth-cohort study is to establish risk factors for asthma and other allergic diseases in childhood.The study is based on 4089 children born [1994][1995][1996] in Stockholm, Sweden.The parents have answered questionnaires on environmental exposure, heredity and allergic symptoms when the child was born and at one, two and four years of age.Dust from mattresses was collected at birth and at four years for analyses of mite-and pet allergens.At the four-year follow-up, the children were invited to an appointment with spirometry and blood samples for analysis of Phadiatop ® as a test for aeroallergens and allergen-specific IgE antibodies to cat, dog and mites (Pharmacia CAP SystemTM).The response rate for the four-year questionnaire was 92% (3742 children).2966 children came to the appointment (73 %), and 2610 (88%) of them consented to blood sampling.Asthma, defined as at least one episode of wheezing after two years of age combined with either bronchial hyperreactivity or prescription of inhaled steroids was fulfilled by 7.9% of the children.Rhinitis defined as sneezing, blocked nose and/or red itchy eyes when exposed to pollen/pets after two years of age was reported by 10.4% of the children.For 20.6% of the children, atopic dermatitis defined as dry skin and rash with typical locations was reported.A positive Phadiatop (>0,35kU/L) was found in 15% of the children.Among those who fulfilled the asthma definition, 32% had a positive Phadiatop, compared to 51% of those with rhinitis and 30% of those with atopic dermatitis.829 children (23%) had only one allergic manifestation (asthma, rhinitis or atopic dermatitis), while 217 children (6%) reported two and 37 children (1%) three manifestations.Positive Phadiatop was found in 22% of the children with one allergic manifestation, 51% in those with two, and 75% of the children with three allergic manifestations.38% of children with positive Phadiatop were positive to cat allergen, 30% to dogs and 12% to mites.75% of the children with asthma and rhinitis were boys, as well as 60% of the sensitised children.In conclusion, sensitisation to aeroallergens was more common among children with rhinitis than among children with asthma or atopic dermatitis, and more common among boys than girls at four years of age.Children with many allergic manifestations showed a higher prevalence of sensitisation.In addition, sensitisation to cats and dogs was more common than to mites.