Avian thymic hormone treatment of peripheral blood mononuclear cells from young chicks stimulates acute graft-versus-host reaction in chicken embryos.

Avian thymic hormone (ATH) is a parvalbumin produced by epithelial cells in the thymic cortex of chickens and circulates in the blood on a 5-day cycle. It stimulates precocious development of cell-mediated immunity. The effect of partially purified extracts of thymus (TE) and purified ATH were tested for their effect on the acute graft-versus-host reaction (GVHR).