Adjuvant effects of crystal proteins from a Mexican strain of Bacillus thuringiensis on the mouse humoral response

In this study, we determined the adjuvant effects of the crystal (Cry) proteins, p130, p98, and p64-62, on the immune response of mice to both sheep red blood cells (SRBC) and ovalbumin (OVA). The administration of p130, p98, and p64-62 Cry proteins to Balb/c mice induced a significant (p < 0.01) increase in the production of anti-SRBC antibody-secreting cells (ASC). The p64-62 Cry proteins demonstrated the best ability to induce the production of IgA and IgG antibodies to SRBC (p < 0.05), and IgM, IgA, and IgG antibodies to OVA (p < 0.05). Additionally, Cry proteins did not produce any side effects associated with their administration to Balb/c mice. We suggest the potential use of the p64-62 Cry proteins as adjuvants for the administration of heterologous antigens.