Anti-human AFP variant monoclonal antibody in radioimmunodetection of primary hepatocellular carcinoma.

AIM: To investigate the affinity of AFP-R-LCA monoclonal antibody (AFP-R-LCA McAb) for AFP-positive primary hepatocellular carcinoma (HCC) cells. METHODS: AFP-R-LCA McAb was labeled by (131)I. Eleven cases of HCC with AFP positivity, 6 with AFP negativity, and 4 with hepatitis B-related cirrhosis were investigated by radioimmunodetection. RESULTS: The (131)I-AFP-R-LCA McAb immunoreacted with 9 of the HCC AFP-positive cases (9/11), but with none of the 6 AFP negative HCC cases or of the 4 cirrhosis patients. (131)I-AFP-R-LCA McAb at a small dose (7.4 × 10(7) Bq/300 µg) was associated with no side effects as determined by the liver function test, prothrombin time (Pt) test and thyroid gland function test (P > 0.05). Two cases of AFP-positive HCC were not imaged because of large tumor size (diameter > 10 cm) and higher AFP concentration in serum (20000 µg/L). CONCLUSION: AFP-R-LCA McAb has a strong and special affinity to AFP-positive HCC cells and may be useful as a carrier for radioimmunodetection and radioimmunotherapy.

Suppression of radioactive strontium absorption by sodium alginate in animals and human subjects.

The effect of 23 sodium alginate preparations from different species of algae (Sargassum sp.) and kelp (Laminaria sp.) on reducing the absorption of strontium was studied in detail. A pilot production procedure has been established. Na alginate from S. siliquastrum was proven to be a potent agent for reducing Sr absorption, with high efficiency and virtually no toxicity. It reduced the body burden of strontium 3.3-4.2 fold in rats. Strontium absorption in human subjects was reduced by 78% (+/- 8.9) or completely suppressed the increase of serum Sr at 2 h after ingestion of stable Sr in volunteers and decrease 24 h urine Sr to similar extent. No undesirable effects on gastrointestinal function was observed nor were Ca, Fe, Cu and Zn metabolism changed, both in the animal experiments and in human. It was concluded that alginate preparations derived from Sargassum species are a suitable antidote against radiostrontium absorption on a long-term basis, when added to bread at a 6% level. In cases of emergency, an alginate syrup preparation appears to be more suitable because of its rapid action.