LYMPHO-RETICULAR STIMULATORY PROPERTIES OF COR YNEBACTERIUM PARVUM AND RELATED BACTERIA

KILLED suspensions of the anaerobic diphtheroid Corynebacterium parvum were shown by Halpern et al. (1964) to possess a marked capacity for stjmu-lating the lympho-reticular system. Treated mice showed large increases in spleen and liver weight and increased ability to clear intravenously injected carbon from the circulation. It has since been shown that C. parvum acts as an adjuvant (Neveu, Branellec and Biozzi, 1964; Biozzi et al., 1966) and that treatment of animals with this organism can protect them from tumour-cell (Halpern et al., 1966; Woodruff and Boak, 1966), protozoal (Nussenzweig, 1967) and bacterial challenge (Adlam, Broughton and Scott, 1972). Protection is also afforded against graft-versus-host disease (Howard et al., 1967). In addition to these properties, C. parvum resembles Bordetella pertussis, an un-related organism that may also act as an adjuvant (Kind, 1957) and possesses the ability to induce splenomegaly (Morse, 1965), in being able to sensitise susceptible strains of mice to endotoxin (Howard, 1968) and to histamine (Adlam et al.). The work of Privot and Tran Van Phi (1964), who showed that several diphtheroid species other than C. parvum stimulate the reticulo-endothelial system to take up injected carbon more rapidly, suggested that the properties possessed by C. parvum might be common to several related species. This possibility was also indicated by the work of Farber and Smith (1969), who showed that a strain of C. acnes possessed reticulo-endothelial stimulatory properties similar to C. parvum. In addition, both C. rubrum (Katsh, 1960) and C. avidm (Giambanco, Armani and Falcone, 1966), like C. parvum (Neveu et aZ.), may be satisfactorily substituted for the mycobacterial com-ponent of Freund's complete adjuvant. In the present work, several species of corynebacteria were quantitativel