An anti‐theta sensitive hapten‐carrier response in nude mice

Spleen cells from congenitally athymic (“nude”) mice were found to give a good anti‐hapten response when cultured with the hapten‐carrier, dinitrophenyl (DNP)‐flagellin, but not when cultured with DNP coupled to two other proteins, hemocyanin and human IgG. This response to DNP‐flagellin was anti‐theta‐sensitive. The evidence indicated that the mice had a small population of T cells, a proportion of which had become primed naturally to flagellin or to related antigens and could function as specific helper cells in a collaborative anti‐DNP response. The existence of such flagellin‐primed T cells was confirmed by the ability of such mice to mount a delayed type hypersensitivity reaction to flagellin injected into the hind footpad.