title: A delayed-type hypersensitivity reaction initiated by a single T lymphocyte.
abstract: In vivo primed T cells injected into the footpad of naïve recipients elicit a typical delayed-type hypersensitivity (DTH) reaction in the presence of their specific antigen. Serial dilutions of primed T cell populations were used in order to score positive and negative transfers. The values for the footpad swelling obtained after these transfers followed a bimodal distribution. This clear bimodal distribution with no overlapping between positive and negative transfers suggested that a single cell initiates the DTH reaction. Limiting dilutions of cloned T cells transferred with their antigen allowed us to demonstrate that a single cell is able to transfer a specific DTH reaction.
mesh_terms: D000818:Animals; D002999:Clone Cells; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006968:Hypersensitivity, Delayed / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000502:physiology*