A B S T R A C T Jones-Mote reactions are delayed, erythematous, and mildly indurated cutaneous reactions originally described in humans sensitized by skin injection of heterologous proteins. Similar reactions in guinea pigs contain many basophils and are called cutaneous basophil hypersensitivity. In contrast, guinea pigs immunized with mycobacterial adjuvants have classical tuberculin-type delayed hypersensitivity reactions, which contain few basophils. This has led to a new classification of delayed responses, based largely on the presence or absence of basophils. We induced sensitization for JonesMote reactions in 20 normal humans by intradermal injections of keyhole limpet hemocyanin. Skin tests with KLH 1 wk later showed erythematous and indurated delayed reactions in all subjects. Rebuck skin windows showed specific accumulations of basophils with a delayed time-course in 18 of 20 subjects. In 12 normals sensitized with oxazolone-keyhole limpet hemocyanin conjugates, skin reactions and in vitro lymphocyte stimulation showed carrier and not hapten specificity, suggesting that cutaneous responses were probably mediated by T cells.A comparative stuidy of strongly positive PPD skin tests in patients with tuiberctulosis showed significant basophil accuimulations in five of nine subjects. Thus, basophils occuirred in human tuibercullin and Jones-Mote reactions and were not a distinguishing feature of Jones-Mote reactions. We suggest that the occurrence of basophils at delayed reactions is under complex regulation and that basophil accumulations are an aspect of delayed hypersensitivity, rather than an indication of a distinctive and separate response.
Dr. Askenase is the recipient of Allergic DiseasesAcademic Award AI-70829, and Dr. Atwood was the recipient of a student fellowship from the Syntex Corporation.