MATERNAL INFLUENCE ON IGG SUBCLASS ANTIBODIES TO BET-V-1 DURING THE FIRST 18 MONTHS OF LIFE AS DETECTED WITH A SENSITIVE ELISA

Background: The initial encounters with allergens are crucial for sens itisation later in life. The IgG1 responses to house dust mite in infa ncy are later accompanied by an IgG4 response, with high levels seen p articularly in atopic children. Little is known of the development of IgG subclass responses to other inhalant allergens. The aims of this s tudy were to develop a sensitive method for the study of postnatal imm une responses to the important seasonal inhalant allergen Bet v 1. Met hods: Antibodies to rBet v 1 were analyzed in 96 children at birth, 6 and 18 months using a sensitive enzyme-amplified ELISA. Results: Immun oglobulin G responses to rBet v1, mainly of the IgG1 subclass, were co mmon in young children, and could at 6 months be demonstrated in sever al infants who had not yet experienced a postnatal birch pollen season . Atopic dermatitis was associated with high levels of lgG subclass an tibodies to birch at 18 months. Maternal atopy was associated with hig h levels of all IgG subclass antibodies to rBet v 1 in cord blood. In postnatally birch-pollen-exposed infants with atopic mothers, the leve ls of IgG antibodies at birth correlated with the levels at 6 months. In contrast, high antibody levels to rBet v 1 at birth were associated with low IgG titres to rBet v 1 at Is months. Conclusions: IgG1 respo nses to birch are common during the first 18 months of life. High leve ls of maternally derived birch-specific IgG antibodies are associated with maternal atopy and may influence the development of the IgG antib ody responses to birch in their child.