FIG. 4.
Prophylactic efficacy of INH-A21 in a rabbit IE model. Female outbred New Zealand White rabbits were treated prophylactically with 300 mg/kg of INH-A21 (n = 15) or 300 mg/kg of normal IGIV (Panglobulin) (n = 8). Twenty-four hours later, the animals were challenged i.v. with either 5.9 ×105 CFU of MRSE 35984 (A) or 5.8 ×105 CFU of MRSA 67-0 (B). Forty-eight hours postchallenge, blood, cardiac vegetations, and kidneys were removed and cultured. Symbols indicate results from individual tissue samples. Horizontal lines indicate group medians. Detection limits in the blood samples were 1 colony/ml. Detection limits in the tissues were dependent on tissue weight and averaged 17 CFU/g for vegetations and 6 CFU/g for kidneys. Infection rates in tissues from INH-A21 treatment groups were significantly reduced in the following groups: cardiac vegetations (P = 0.0094); blood (P = 0.0017) (S. epidermidis challenge) (A); cardiac vegetations (S. aureus challenge) (P = 0.0086) (B). Bacterial densities were also significantly reduced compared to controls in cardiac vegetations (P = 0.007) of animals challenged with S. epidermidis (A). Significant P values are indicated on the graphs.