The intermediate-affinity interleukin (IL)2 receptor expressed on Theileria annulata-infected cells comprises a single IL 2-binding protein. Partial characterization of bovine IL2 receptors.
Bovine high-, intermediate- and low-affinity interleukin 2 receptors (IL2R) were studied by ligand binding and affinity labeling using 125I-labeled IL2 and homobifunctional chemical cross-linking reagents. High- (Kd = 17 pM) and low-affinity (Kd greater than 6 nM) IL 2R were detected on concanavalin A-activated peripheral blood lymphocytes (PBL). Theileria annulata (TA)-infected autonomously growing PBL (TA-PBL) express predominantly intermediate-affinity IL2R (Kd = 1 nM). Affinity-labeling studies revealed that the high-affinity IL2R comprises a 55-kDa (L chain) and an additional 90-kDa IL 2-binding protein (H chain). TA-PBL express predominantly the H chain. In contrast to the human chain, the bovine form was not separable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/urea into the two distinct bands H1 and H2 and ran in parallel to the human H2 band. These results suggest (a) that the bovine intermediate-affinity IL2R comprises a single H chain and (b) that the single H chain and the L chain are sufficient to form the functional high-affinity bovine IL2R.
Herrmann
T
T
Institut für Immunologie, Klinikum Steglitz, Berlin, FRG.
Ahmed
J S
JS
Diamantstein
T
T
D000345:Affinity Labels; D000818:Animals; D002417:Cattle / Q000276:immunology*; D007376:Interleukin-2 / Q000378:metabolism*; D008970:Molecular Weight; D015375:Receptors, Interleukin-2 / Q000032:analysis / Q000378:metabolism / Q000648:ultrastructure*; D013601:T-Lymphocytes / Q000032:analysis* / Q000378:metabolism; D013801:Theileriasis / Q000276:immunology*
D000345:Affinity Labels; D007376:Interleukin-2; D015375:Receptors, Interleukin-2