Regression of S-180 sarcoma using a xenogeneic antiserum.

Tumour angiogenesis factor (TAF) was extracted from S-180 sarcoma grown as a solid tumour in Swiss albino mice. Its angiogenic activity was detected using the mouse intradermal and the chick chorioallantois membrane assays. Similar extracts from normal tissues failed to induce neovascularisation. An antiserum raised in rabbit, against TAF purified from mouse mammary adenocarcinoma was shown to neutralise the biological activity of TAF from S-180 sarcoma and also caused tumour regression in the mice. A possible therapeutic approach to solid tumours is indicated, as also the preparation of an immunotoxin.