Salivary IgA is produced by plasma cells in connective tissue around salivary glands. IgA in the alimentary system is produced by plasma cells in the lamina propria. It is the only Ig that can cross into the lumen of the alimentary tract. During lactation, the levels of IgA increase so that it becomes the predominant immunoglobulin in the milk (more than [[IgG]]). Mucosal epithelium have a “poly Ig receptor” and this bind to the J chain on the IgA, and allows IgA to travel across the cell. IgA crosses the cell in a transport vesicle and is released by exocytosis. | Salivary IgA is produced by plasma cells in connective tissue around salivary glands. IgA in the alimentary system is produced by plasma cells in the lamina propria. It is the only Ig that can cross into the lumen of the alimentary tract. During lactation, the levels of IgA increase so that it becomes the predominant immunoglobulin in the milk (more than [[IgG]]). Mucosal epithelium have a “poly Ig receptor” and this bind to the J chain on the IgA, and allows IgA to travel across the cell. IgA crosses the cell in a transport vesicle and is released by exocytosis. |