Analyse quantitative in vivodes réctions immunitaires dirigées contre les antigénes associés a des tumeurs murines solides

The dose-response curves and the TD50 are considered to be biological characteristics of tumors. Further these parameters vary according to the immunological status of the host. By using the TD50 method, a quantitative in vivo determination has been made of immune reactions directed against tumor-associated transplantation antigens (TATA) of three solid murine tumors. The intensity of the primary immune reaction is evaluated by the difference between the TD50 values in normal and immune-depressed animals. On the other hand, the secondary immune response is estimated by the difference between the TD50 in normal and specifically immunized recipients. According to these criteria, the results show that the intensity of the primary and secondary immune reactions cannot be compared from one tumor to another. For one tumor, the secondary reaction is quantitatively much greater than the primary reaction. For another tumor, the exact opposite is the case. These results suggest that there is no correlation between the primary and secondary immune responses and that they are quantitatively dependent upon multiple factors. The results are discussed in relation to the determination of antigenic strength of tumors.