Immunodeficiency in the chicken. III. Hypoplasia of bursal follicles following intravenous injection of embryos with lipopolysaccharide or allogeneic lymphocytes.

Intravenous injection of LPS or allogeneic lymphocytes resulted in impaired maturation of B cells within the bursa of chick embryos. A gradual decline in the sensitivity of embryos towards both agents was reflected by a decrease in the number and size of bursal follicles following injection between 10 and 15 days of embryonation. The hypoplasia of these follicles in embryos injected with lymphocytes on the 10th day was a more sensitive measure of graft-versus-host reaction than splenomegaly. The relevance of results with this model to the aetiology of immunodeficiency diseases has been briefly discussed.