Heat labile and heat stable factors and antibodies in normal and immune sera against T-system bacteriophages

Abstract

1. Heat labile and heat stable inactivating factors against T-system phages are present in normal guinea-pig and rabbit sera. These may be antibodies.2. Sera of guinea-pigs immunized with phages T2, T3 and T4 contain heat labile and heat stable antibodies.3. The heat labile activity is absorbed from guinea-pig serum by phage more readily than the heat stable activity.4. Dilution of the sera reduces the heat labile activity more than the heat stable activity.5. Complement has no effect on the inactivation or neutralization of phages T2, T3 and T4 by normal or immune guinea-pig sera.