An anti-okadaic acid-anti-idiotypic antibody bearing an internal image of okadaic acid inhibits protein phosphatase PP1 and PP2A catalytic activity.
Okadaic acid (OA), produced by marine phytoplankton, is the parent compound of a family of marine toxins responsible for diarrheic shellfish poisoning (DSP). A monoclonal antibody to OA (6/50) (Ab1) has been raised and in turn used for immunization of syngeneic animals. Mice inoculated with the 6/50 idiotype produced both anti-idiotypic antibodies (Ab2) and OA binding antibodies (Ab3). The selected anti-idiotypic antibody 1/59 bound to the immunizing 6/50 idiotype but not to F(ab')2 fragments of pooled normal mouse Ig. It inhibited the binding of OA to solid-phase attached F(ab')2 of 6/50 IgG as well as the binding of 6/50 IgG to a solid-phase bound OA. Like OA, 1/59 anti-idiotypic antibody inhibited protein phosphatase 1 and 2A catalytic subunits in a 32P-phosphorylase a phosphatase radioassay. Thus, 1/59 IgG is a novel internal image anti-idiotypic antibody (Ab2 beta) and can serve as a surrogate of OA in biological assays.
Shestowky
W S
WS
Rougier Bio-Tech Ltd., Montreal, Québec, Canada.
Holmes
C F
CF
Hu
T
T
Marr
J
J
Wright
J L
JL
Chin
J
J
Sikorska
H M
HM
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology* / Q000378:metabolism; D002384:Catalysis; D004988:Ethers, Cyclic / Q000276:immunology*; D006825:Hybridomas; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D051379:Mice; D019319:Okadaic Acid; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors*; D054645:Protein Phosphatase 1; D014407:Tumor Cells, Cultured
D000888:Antibodies, Anti-Idiotypic; D004988:Ethers, Cyclic; D007527:Isoenzymes; D019319:Okadaic Acid; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1