The Morphology of the Phytohemagglutinin-Induced Cell Response in the Chicken's Wattle

Abstract

Phytohemagglutinin (PHA), 100 μg, was injected into the wattle of chickens, and histological changes were studied by light and transmission electron microscopy. Within 30 min of the PHA injection several postcapillary venules contained mononuclear cells and heterophils. Basophils and eosinophils increased in number throughout the wattle 24 hr after PHA injection, while lymphocytes were restricted to the vicinity of the postcapillaries. Lymphocyte numbers increased 48 hr after PHA injection while the number of granulocytes declined. Multinucleated cells were found and appeared to be formed by fusing of cell membranes of mononuclear cells. Before lymphocyte infiltration, many small lymphocytes could be seen in the wall of the postcapillaries indicating their origin as blood borne. Many of the high endothelial cells which appeared subsequent to the injection of PHA were revealed to be in S phase.