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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Immunoglobulin present in mouth local secretion s-
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The correct answer is  Ans. is 'a' i.e., IgA IgAo It is the second most abundant antibody (after IgG).o It is major immunoglobulin in clostrum, saliva, tears, respiratory and gastrointestinal secretions. Ig A occurs in two forms.IgASerum IgASecretory IgA (SIgA)o Monomero Dimero Found in serumo Two monomer units are joined together by a glycopeptide - Jchain o Contains glycine rich polypeptide secretory component, which protectsIgA from denaturation by bacterial proteases.o SIg A and J chain are synthesized by plasma cells.o Secretory component is produced by mucosal or glandular epithelial cells.o Two subclasses of IgA have been described Ig A| & Ig A?.IgAI - Predominant serum Ig AIg A2 - Predominant secretory Ig A