Successful Growth of Tumor Allografts Following Explantation

Summary

Alteration in the antigenicity of a Leydig cell tumor following short-term maintenance in organ culture and manifested by progressive growth of the tumor in allogeneic hosts occurs following incubation in media independent of the following factors: (i) presence or absence of antibiotics in the medium, (ii) incubation at 32 or 37°, (iii) incubation in 5% CO₂ in air or in oxygen, and (iv) presence or absence of 10% fetal calf serum in the medium. The frequency of successful allografts is greater in tumors explanted for 6 days than for those cultured for 1 or 2 days. The alteration occurred more frequently after maintenance in Hanks’Balanced Salt Solution and Waymouth Medium than it did after maintenance in medium 199. The occurrence of in vitro-induced alteration in tumor specificity is discussed in relation to other conditions known to alter immunologic specificity and the possible relationship of these to the phenomenon of immunologic enhancement is suggested.