Detection of IgA Anti-Escherichia Coli Plasma Cells in the Intestine and Salivary Glands of Pigs Orally and Locally Infected with E. Coli

Abstract

The neonatal pig is virtually devoid of maternal antibody at the time of birth. It receives the maternal antibodies through the colostrum. These antibodies are absorbed intact by the neonatal intestine. After 24–48 h these neonatal intestinal epithelial cells are replaced and the ability to absorb intact immunoglobulins is lost (1). Although in pigs IgG1 and IgG2 are the most abundant immunoglobulin in colostrum, IgA becomes the predominant immunoglobulin in the sows milk (2). Maternal s-IgA from milk has been demonstrated to have a major role in protecting the neonatal piglet from viral and bacterial intestinal infections (3,4). It has been further proven that most of this s-IgA in milk is produced locally in the mammary gland by IgA plasma cells. It was postulated, that these IgA plasma cells originated in the intestinal mucosa after infection of the sows intestinal tract; IgA blast cells would leave the mucosa and “home” to other exocrine secretory sites such as the mammary and salivary glands (5).