Abstract: Objective  To develop a method for the immunotoxicological evaluation of vaccines in a guinea pig model, and to preliminarily evaluate the immunotoxicological effects of a new tuberculosis vaccine (smegmatis vaccine).  Methods (1) Thirty guinea pigs were prepared the allergy models, and 15 as negative controls. The total IgG1 antibody in serum and the content of allergic media in the bronchoalveolar lavage fluid and the culture supernatants from the peripheral blood basophils and mast cells in peritoneal lavage fluid in vitro simulated were detected by ELISA. (2) The guinea pigs were divided into 3 groups as follow: allergy model, smegmatis vaccine and negative control. Their immunotoxicological effects were preliminarily evaluated using the methods developed above.  Results The optimal experimental conditions for the detection of total IgG1 antibody in sera from guinea pigs included that 6 μg/ml goat anti-guinea pig IgG1 antibody was coated,  the serum sample was diluted 1:10⁵, and horseradish peroxidase labeled goat anti-guinea pig IgG1 antibody was diluted 1:20 000. In the culture supernatant of  peripheral blood basophils simulated in vitro in the allergy model group and negative control group, the histamine contents were （99.37±15.34）nmol/L and （29.94±5.86）nmol/L, and leukotriene levels were （13.09±3.87）pg/ml and （2.22±0.53）pg/ml, respectively. In the supernatant of bronchoalveolar lavage fluid, the histamine contents were (73.42±18.60) nmol/L and (31.00±12.09) nmol/L, and leukotriene levels were (123.20±16.57) pg/ml and (39.05±16.94) pg/ml, respectively. In the culture supernatant of peritoneal lavage fluid simulated in vitro, the histamine contents were (39.59±12.94) nmol/L and (14.35±5.85) nmol/L, and leukotriene levels were (6.79±2.58) pg/ml and (3.09±1.18) pg/ml, respectively. Both of the contents of histamine and leukotriene in three kinds of samples mentioned above were significantly different between the allergy model group and control group (histamine: t=12.60, t=5.41, t=5.20, P<0.05; leukotriene: t=8.46, t=9.15, t =3.85, P＜0.05). The abnormal immunotoxicological effects were not observed in the safety evaluation of smegmatis vaccine by the methods above.  Conclusion  The method for immunotoxicological evaluation of vaccines was preliminarily established. The smegmatis vaccine proved preliminarily to be safe.

Key words: Tuberculosis vaccines, Toxicology, Hypersensitivity, immediate, Mycobacterium smegmatis, Evaluation studies