FLUORESCENT PROTEIN TRACER STUDIES IN ALLERGIC REACTIONS .1. FATE OF FLUORESCENT ANTIGEN IN ACTIVE AND PASSIVE ARTHUS REACTION IN GUINEA-PIG SKIN

Abstract

The fate of intradermally injected bovine serum albumin, labelled with lissamine rhodamine was studied in actively and passively sensitized guinea pigs, and compared with the fate of the same protein in control animals. In the latter, the antigen is taken up by macrophages, apart from a discharge of antigen to the regional lymph nodes. In the sensitized animals, in which severe Arthus reactions occurred, an accumulation of antigen in vessel walls and lumina of capillaries and venules was observed. Polynuclear leucocytes take antigen after a few hours. This is a specific reaction absent with simultaneously injected protein to which the animal is not sensitized.