Effect of antibodies to staphylococcal alpha and beta toxins and Staphylococcus aureus on the cytotoxicity for and adherence of the organism to bovine mammary epithelial cells.

OBJECTIVE

To determine the effect of antibodies to staphylococcal alpha and beta toxins and Staphylococcus aureus on the toxicity for and adherence of S aureus to bovine mammary epithelial cells.

SAMPLE POPULATION

Cultured bovine mammary epithelial cells and Staphylococcus aureus obtained from a cow with mastitis.

PROCEDURE

Cultured bovine epithelial cells were incubated with antisera to alpha and beta toxins of S aureus and culture supernatant; cell damage and S aureus adherence to cells were measured.

RESULTS

Antisera to alpha, beta, and alpha + beta toxins inhibited cytotoxicity of S aureus culture supernatant. Antiserum to alpha + beta toxin was the most effective inhibitor of cytotoxicity and antiserum to beta toxin was the least effective. All 3 antisera decreased the percentage of S aureus adhered to the mammary epithelial cell monolayers and numbers of organisms per cluster of adhered bacteria. In this study, antisera to alpha and alpha + beta toxins decreased the number of S aureus clusters per dish, but antiserum to beta toxin had no significant effect. Antiserum to alpha + beta toxin decreased the percentage of epithelial cells with adhered S aureus, but neither antiserum to alpha nor beta toxin had significant effect. Antiserum to S aureus decreased the percentage of S aureus adhered, number of clusters perdish, number of organisms per cluster, and percentage of epithelial cells with S aureus adhered.

CONCLUSIONS

Antibodies to staphylococcal alpha and beta toxins inhibit adherence to and cytotoxicity of S aureus for bovine mammary epithelial cells, and antibodies to S aureus inhibit adherence of S aureus to bovine mammary epithelial cells.