Antibodies to CP5-ClfB reduced the mean CFU/abscess recovered from mice challenged with CP5 strain Newman (P = 0.015) compared to the mice given NRS but did not reduce bacterial burdens when the animals were infected with a CP− strain LAC (P = 0.38) (Fig. 5b), suggesting antibody to ClfB was not providing much protection is this setting. The gene discussed is CP; the disease is abscess.