Fig. 4

Inhibition of the binding of live Pg cells to wsHAPs by SIgA Ab-enriched saliva in wild-type (IgA^+/+) or by saliva from IgA^−/− mice given nasally both stat23 and prp21 with/without dDA. An aliquot (100 µL) of SIgA Ab-enriched saliva (i.e., saliva from which IgM and IgG Abs had been removed using affinity columns chromatography) or IgA^−/− mice saliva samples were added to wsHAPs in the was added to wsHAPs in siliconized glass tubes; the mixtures then was incubated for 3 h at room temperature. Subsequently, the wsHAPs were washed three times with 500 µL of KCl buffer and Pg ATCC 33,277 (1 × 10⁸ cells in 200 µL of KCl buffer) was added to each tube. After incubation for another 3 h at room temperature, the HAPs were washed three times with 500 µl of KCl buffer and then transferred to white 96-well plates. The levels of ATP (indicative of live Pg cells bound to the wsHAPs) were determined using a luciferase assay and luminometer. Values are presented as the mean ± SE from three replicates. Comparisons were performed by two-tailed unpaired Student’s t-test. *p < 0.05