Summary

1. Treatment of actively sensitized animals with various gold preparations delays the onset of the characteristic paralysis of EAE and appreciably diminishes the severity of the disease, as reflected in reduced weight loss of the gold-treated animals.

2. When the EAE was passively transferred by sensitized lymph node cells; treatment of the animals donating the cells prior to transfer, or incubation of the “pathophoric” node cells with gold preparations in vitro, did not retard the subsequent development of the disease in the recipient animals.

3. Treatment of recipient rats at, and after, the time of transferring sensitized lymph node cells, both delayed and attenuated the passively transferred disease.

4. Gold preparations apparently exert their beneficial effect upon EAE at a stage after the initial sensitization with encephalitogen.

5. Daily intramuscular treatment with 8 mg/kg aurothiomalate gave lower serum gold levels, but more effectively suppressed the disease, than treatment with 25 mg/kg aurothiomalate every third day.

6. Triethylphosphino gold chloride (SK& F 36914), a new lipophilic gold preparation, given either im or po, was approximately as effective as equal doses of sodium aurothiomalate in delaying the onset and decreasing the severity of the EAE.

7. Sodium aurothioglucose in sesame oil suspension (Solganal) was more effective than equal doses of aqueous aurothioglucose when given every third day. However, on the daily injection regimen, aqueous aurothioglucose protected animals more efficiently than the oily suspension.

We are indebted to Dr. D. T. Walz for supplying SK&F 36914, Mrs. Darling J. Whitehouse for surgical assistance, Dr. B. B. Newbould for demonstrating the cell-transfer technique, Dr. C. M. Pearson for encouragement and the National Institutes of Health for financial support (GM-15759).