Evaluation of mouse salivary IgA directed against indigenous oral bacteria

We are developing an ELISA to follow the evolution of specific salivary IgA directed against the indigenous oral bacteria of the BALB/c mouse. To reduce the variability of the IgA levels detected between different mice, we standardized the method used for sampling saliva and the method used for bacterial cell fixation. Incubation of whole bacteria for one hour at 4 degrees C in poly-L-lysine-treated plates followed by glutaraldehyde fixation increased ELISA reactivities by improving cell fixation. Our results also indicate that salivary IgA concentrations in BALB/c mice peak at the age of three months and that biweekly carbachol-stimulated saliva sampling does not significantly affect the amount of salivary IgA detected.