Studies on Human Prostatic Acid Phosphatase. IV. Stabilization of Prostatic Acid Phosphatase against Thermal Inactivation by the Homologous Antibody
キーワード:
fragments Fab and F (ab')2
1981 年 29 巻 10 号 p. 2934-2939
詳細
1981 年 29 巻 10 号 p. 2934-2939
Antibody against purified human prostatic acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) was produced in rabbits. The antiserum stabilized the activity of the enzyme against heat treatment, such as incubation at 56°C for 30 min, whereas normal rabbit serum displayed no stabilizing effect. We isolated IgG by ammonium sulfate fractionation and affinity chromatography on a Protein A-Sepharose CL-4B column. the IgG fraction showed a remarkable heat-stabilizing effect on prostatic acid phosphatase (PAPase) and the heat-stabilizing factor was purified 4.2-fold by the IgG isolation method. Complex of PAPase and PAPase specific IgG was separated from a mixture of PAPase and antiserum by a combination of Protein A-Sepharose CL-4B column and Sephacryl S-300 column chromatographies. The immune complex displayed heat stability. IgG which failed to bind PAPase had no heat-stabilizing effect on PAPase. Fab fragments obtained by papain digestion showed a low heat-stabilizing effect, whereas F(ab')2 fragments obtained by pepsin digestion displayed a heat-stabilizing effect comparable with that of the IgG fraction.
