Abstract
Hyperimmunized anti-α-toxin horse serum failed to protect mice from lethal infection by virulent staphylococcus, while it protected mice from the intoxication by α toxin. On the other hand, it was elucidated that α toxin was able to promote the invasiveness of avirulent staphylococcus in mice. Therefore, it was suggested that a different factor in addition to α toxin ought to play a roll in virulent staphylococcal infection.
Passive immunization by antibacterial horse serum and active immunization of mice by vaccine or toxoid also failed to protect them from lethal infection. Thus, it seems that humoral factor in immunity in staphylococcal infection is quite limited.
