EXTREMELY ACTIVE MURINE AMYLOID ENHANCING FACTOR

Objective. To generate and characterize a highly active amyloid enhanc ing factor (AEF). Methods. AEF was obtained from amyloidotic and pre-a myloidotic mice spleens that were homogenized in 50% acetone in H2O. T he grade of AEF enhancing activity was studied in relation to the proc edure used to generate the AEF, the amount of AEF administered, the du ration of amyloid induction and the effect of solvent and denaturing a gents. Results. Both priming of the splenic source of the AEF with an amyloidogen and acetone processing were essential for the AEF activity . AEF in a single intravenous dose as low as I nanogram per mouse indu ced amyloidosis in mice within 2-6 days. Polyacrylamide gel electropho resis of the AEF showed two protein bands of molecular weight (MW) 9 - 11 KD not present in normal spleen homogenates. Dialysis of the AEF s howed that the active components can pass through a dialysis bag with an MW cutoff of 12 KD. Conclusions. These findings suggest that ours i s the most active AEF currently available and that it has active const ituents of low MW (less than or equal to 12 KD) which appear in the sp leen during amyloidogenesis.