Effect of emetine on the plasma cell population of chicken's gland of Harder.

The emetine effectively abolished the plasma cell population in the chicken's gland of Harder by day 3 of treatment. The plasma cell content regenerated by day 5 following emetine injection, possibly from a metabolically inactive, resting B cell population which was resistant to the emetine treatment. By day 7 extracellular substance in a very large quantity appeared among the plasma cells and epithelial cells which might represent a hyperactive plasma cell secretion. The changes in the circulating antibodies measured by hemagglutination well-correlated with the plasma cell content in the gland of Harder. The gland of Harder (GH) is an accessory lacrimal gland. Its main function is to lubricate the nictitating membrane and keep the surface of the eyeball wet. The presence and regulatory function of cAMP dependent histone kinase was showed. Since it has been published that in chicken the interstitium of this gland contains a proper amount of plasma cells, this observation called the attention of many investigators to study the role of GH in the immune response. The B cell maturation in the chicken GH has been studied. The surface marker studies have proved that beside the B cells the gland contains functionally adequate number of T cell which exert stimulatory effect on B cells to promote their transformation to plasma cells. In addition to T and B cells small number of macrophages also occur. In the 9 H the number of plasma cells is age dependent. At hatch only a few plasma cells occur in the interstitium of the gland but by 3 weeks of age they become predominant. Different isotypes of immunoglobulins are secreted by these plasma cells.