Delayed hypersensitivity in the rabbit after injection of viable "NSU Corynebacteria".

'NSU Corynebacteria' are commensals of the normal male and female urogenital tracts (Furness, Kamat, Kaminski, and Seebode, 1973). They are so called because they were first described in association with NSU (Fmrness and Csonka, 1966), and the term is retained so that they should not be confused with other diphtheroids, which in contrast are easily isolated on commercial media and are well-known commensals. Although commonly commensals, 'NSU Corynebacteria' have been isolate in pure culture from the epididymis of patients with acute epididymitis (Furness and others, 1971a, 1974) and from the bulbous urethra of patients with non-specific urethritis (NSU) (Furness and Csonka, 1966; Furness and others, 1971b). These reports suggest that some strains may cause disease while others are saprophytes. However, some of the conceivably pathogenic strains isolated from the epididymis of patients with epididymitis and the bulbous urethra of patients with NSU show characteristic biochemical reactions which differentiate them from the commensal 'NSU Corynebacteria' (Furness and others, 1973). Since Reiter's disease and chronic NSU have manifestations suggestive of an allergic syndrome, the ability of 'NSU Corynebacteria' to induce hypersensitivity and to produce antibodies in rabbits has been investigated, and the results are reported below.