The proteolysis of immunoglobulin G with long-acting thyroid-stimulating activity.
1. Proteolysis of immunoglobulin G with long-acting thyroid-stimulating activity with papain and pepsin shortened the duration of thyroid stimulation in mice prepared for the McKenzie (1958) bioassay. The time-course appeared to be related to molecular size. 2. The activity after proteolysis was recovered solely in the electrophoretically slow F(ab)-fragment. 3. There was no immunological cross-reaction between pituitary thyroid-stimulating hormone and the active fragments of the long-acting thyroid stimulator despite their similar behaviour in the bioassay. 4. The implications of these findings are discussed.
D000818:Animals; D000937:Antigen-Antibody Reactions; D055598:Chemical Phenomena; D002621:Chemistry; D008135:Long-Acting Thyroid Stimulator; D051379:Mice; D010206:Papain; D010434:Pepsin A; D014461:Ultracentrifugation; D005719:gamma-Globulins
D005719:gamma-Globulins; D008135:Long-Acting Thyroid Stimulator; D010206:Papain; D010434:Pepsin A