Role of the Harderian gland in immunoglobulin A production in chicken lacrimal fluid

The role of the Harderian gland (HG) in the production of immunoglobulin, especially IgA, was investigated. Lacrimal immunoglobulin almost disappeared after surgical removal of the HG and immunoglobulin produced by HG cells was detected in saliva but not in the trachea. Immunoglobulin production occurred in HG cell culture in vitro and it consisted mostly of IgA; the production of IgM and IgG was very low. These findings indicate that lacrimal IgA is produced locally in the HG and lacrimal IgG and IgM are mostly transported from the blood.