Einschichtiger Zellrasen von Lewin-Fibroblasten. Bewegung von Lymphozyten (Rattenstamm DA) auf den Fibroblasten am 1. und 2. Tag. Zerstörung der Lewis-Fibroblasten durch DA-Lymphozyten am 3. Tag: Einziehen der Fortsätze, Abheben vom Boden, Zell-Lyse der Fibroblasten. Kontrollversuch mit Fibroblasten vom Rattenstamm DA: keine zytotoxischen Reaktionen der DA-Lymphozyten (Original).

Lymphocytes from DA rats are cultivated on LEWIS fibroblasts. On days 1 and 2 the DA lymphocytes recognize the foreign histocompatibility antigens on the LEWIS fibroblasts. They begin to proliferate and to differentiate. On day 3 destruction of LEWIS fibroblasts by sensitized DA lymphocytes is beginning. The exat mechanism of this target-cell-destruction is still unknown. As shown in the film, direct contact between aggressor and target cell is necessary for destruction to occur.