Tissue specificity and species cross-reactivity of porcine zona antigens isolated by gel filtration.

Antisera raised against two different doses of a major component of porcine zona pellucida isolated by gel filtration formed two precipitin lines with the components in agar double-diffusion gel. The antisera produced a positive immunofluorescence on the zona pellucida in sections of ovaries of pig, human, baboon, cow, sheep, rabbit, rat, mouse, hamster, and guinea pig. The antisera did not react with 58 different porcine tissues or five body fluids by immunofluorescence or immunodiffusion. No changes were observed in the fluorescence on the zona or in the precipitin lines when the antisera were previously absorbed with liver, erythrocytes, or plasma; however, after absorption with the porcine zona component both fluorescence and precipitin lines were completely abolished. Furthermore, control antisera against porcine erythrocyte ghosts and follicular fluid did not develop any immunofluorescence on the porcine zona. Both antisera to PZ-alpha and PZ-beta obtained by use of preparative SDS-PAGE developed the same immunofluorescence on the porcine zona shown by the antiserum to the zona component. These findings indicate that the major component of the porcine zona contains at least two zona-specific antigens, which have cross-reactivity with zona antigens of several other mammals, including humans.