An intriguing observation is the intragroup variation for C57BL/6 mice sensitized with any of the four CPE compared to a lower variation of Balb/c mice to the same protein extracts except for CPE- BB2βME (Fig 4).

Fig 4. Titer of the sera of C57BL/6 mice (A) and Balb/c mice (B) sensitized with Crude peanut extracts tested on ELISA plates adsorbed with the antigens corresponding to the immunization. N = 5. p <0.05 = *; p <0.01 = **; p <0.001 = ***; p <0.0001 = ****

Next we examined whether different protein extracts of a given seed used to coat polystyrene microtitration plates influenced the antibody titers. Plates coated with CPE-BB2ßME (Fig 5A) or CPE-TB/HCl (Fig 5D) did not distinguish sera reactivity derived from C57BL/6 mice sensitized with any of the four peanut extracts. However, the same sera from CPE-BB2ßME sensitized animals showed significant differences when compared to sera of those sensitized with CPE-BB on plates adsorbed with either CPE-BB (Fig 5B) or CPE-SB (Fig 5C) (p<0.05 and p<0.01, respectively). Thus, the reactivity pattern differs according to the protein extract used to coat the microtitration plates.