Preparation of various fractions from Mycobacterium smegmatis, their arthritogenicity and their preventive effect on adjuvant disease.

Cell walls of Mycobacterium smegmatis were able to produce much more severe arthritis in rats than the delipidated cells, whereas cell envelope and cell membrane fractions were unable to produce the disease. The lysozyme-solubilized product was able to produce mild disease with only 30% of incidence with an optimum dose, whereas the higher and the lower doses did not produce the disease. The rats immunized with cell envelope, cell membrane fraction and nonarthritogenic doses of lysozyme-solubilized product were protected against the subsequent homologous and heterologous challenge of delipidated cells. It was discussed that this preventative effect can be the result of antigenic competition between the arthritogenic and nonarthritogenic components of M. smegmatis. On the other hand, all the fractions separated here were able to serve as an immunoadjuvant in terms of inducing delayed hypersensitivity to ovalbumin in guinea pigs.