Is allergic disease programmed in early life?

Is allergic disease programmed in early life?Studies of plant and animal development provide ample evidence that environmental influences occurring early in life may produce long-lasting changes in the structure or function of an organism.In recent years, the concept of 'programming' of human development has been vigorously promoted and creatively investigated by the Medical Research Council's Environmental Epidemiology Unit at Southampton, UK, particularly in the context of cardiovascular and respiratory disease [1].Immunology also provides many examples of biological programming, and it would not be surprising to find evidence that immune function in general, and allergic sensitization in particular, were influenced by events occurring early in hfe.A number of lines of enquiry, including the latest observations by the Southampton team [2], suggest that the environment during the perinatal period may be of considerable importance in the expression of atopy among genetically susceptible individuals. Early growthGodfrey et al. [2] measured levels of serum IgE among men and women aged about 50 years whose weight and dimensions at birth had been recorded in unusual detail.They report an association of raised IgE levels with increased head circumference and weight at birth, independent of circumstances in adult life.Head circumference was found to be the more infiuential factor, with no significant effect of birthweight at any given head circumference.Nevertheless, the authors suggest that babies with a large head circumference at birth may tend to outgrow their placental nutrient supply and preserve cranial growth at the expense of the trunk, including the thymus.They speculate that thymic undernutrition may programme the development of TH-! and TH-2 lymphocyte populations in the direction of TH-2 dominance.