[Antigenicity tests of a new antineoplastic agent S-1]

The antigenicity was tested of a new antineoplastic agent S-1 (a combination of tegafur (FT), CDHP and potassium oxonate (Oxo)) in mice and guinea pigs. 1. Male BALB/c or C3H/He mice were sensitized with S-1, CDHP, Oxo, and conjugates of CDHP (or Oxo) and human serum albumin (HSA). S-1 was administered by oral gavage, and the other compounds were administered intraperitoneally with adjuvant (alum). In the heterologous passive cutaneous anaphylaxis (PCA) test, using Sprague-Dawley rats as recipients, no IgE antibodies against S-1, CDHP, or Oxo were detected to any serum obtained from the sensitized mice, and no eliciting antigenicities were seen for CDHP or Oxo. 2. Male Hartley guinea pigs were sensitized with S-1, CDHP, Oxo, and conjugates of CDHP (or Oxo) and HSA. S-1 was administered by oral gavage, and the other compounds were administered subcutaneously with Freund's complete adjuvant (FCA). The homologous PCA test, active systemic anaphylaxis test, and passive hemagglutination test showed no production of antibodies against S-1, CDHP, or Oxo in any sensitized guinea pig, and no eliciting antigenicities for CDHP or Oxo. 3. Female Hartley guinea pigs were sensitized with S-1 subcutaneously with FCA. The active cutaneous anaphylaxis test revealed that S-1 did not induce cell-mediated delayed type hypersensitivity. 4. These results indicated that S-1, Oxo, and CDHP were not antigenic in mice and guinea pigs.