Fig. 5
The protective effect of the MS473 scFv on the liver of D-galactosamine-sensitized mice injected with TSST-1. (A) D-galactosamine-sensitized mice injected with TSST-1 did not show increases in serum ALT and AST levels when treated with MS473 (D-Gal + TSST-1 + MS473) intraperitoneally (IP) five minutes after the toxin injection or intravenously (IV) ten minutes after the toxin injection. In contrast, these levels were elevated in D-galactosamine-sensitized mice injected with TSST-1 and then received normal saline (D-Gal + TSST-1 + NS). Furthermore, similar results were found in TSST-1-injected mice receiving an unrelated scFv (D-Gal + TSST-1 + EB211) intraperitoneally five minutes after the toxin injection or intravenously 10 min after the toxin injection. Statistical significance was determined by one-way ANOVA, followed by Dunnett’s multiple-comparison test against the control group, D-galactosamine-sensitized mice injected with the LD50 of TSST-1 and then received NS. (B) The liver tissue samples from healthy mice receiving NS or D-Gal showed normal architecture. However, necrosis of the hepatocytes (white arrows), extensive disruption of the hepatocyte plates, rupture of the plasma membrane (yellow arrowheads), and hemorrhage (yellow arrows) were observed in D-galactosamine-sensitized mice injected with TSST-1 and then received NS or EB211. On the other hand, when D-galactosamine-sensitized mice were injected with TSST-1 and administered a single dose of MS473, the liver tissue structure was normal. However, slight disorganization of the hepatocyte plates and foci of lobular inflammation (white arrowhead) were observed in some fields