Secretory immunoglobulin a in the oral passages in man

Summary Al’TD Conelusion The appearance of the different classes of immunoglobulins in blood following stimulation by different antigens - is the characteristic torm of humoral Lmmun L ty. While IgA forms only 17% of the total imm~Ulo-globulins in humans serum, it is the major immunoglobuli~ of local secretions i.e. those obtained from organs having direct access to the external environment e.g.salivary secretion. This form of IgA known as secretory IgA (SIgA). is related to the protection of the mucous memb’ranes and their local immunity. This work has been conducted in the E.N.T. and br>biochemistry departments, Faculty of Medicine, Zagazig University and is concerned with the study of IgA in serum and salivary secretion of normal healthy Egyptian subjects at different ages.To achieve this, 100 normal subjects, of different ages and both sexes, were selected and classi- fied into 5 groups. IgA was then determined in their sera and salivary secretions using single radial immuno- diffusion technique, and the following was obtained.