Production of a monoclonal antibody that defines the alpha-subunit of the feline IL-2 receptor.
A mAb, termed 9F23, to feline Con A-stimulated PBMC was prepared to characterize feline IL-2R. 9F23 was identified by FACS studies, which showed that the antigen was expressed at a high density on Con A-induced feline T cell blasts while 9F23 binding was not detected on nonactivated PBMC or the Crandell feline kidney cell line CRFK. Chemical crosslinking of 125I-IL-2 to membrane IL-2Rs on Con A-stimulated feline PBMC under the low-affinity condition resulted in detection of a major 65-kDa band. 9F23 specifically immunoprecipitated the IL-2.IL-2R alpha complex in a cell extract; in contrast, neither anti-human IL-2R alpha H48 nor anti-mouse IL-2R alpha 7D4 reacted with the complex. Moreover, immunoprecipitation with 9F23 of the extract from surface-iodinated Con A-stimulated PBMC showed a major 50-55 kDa band. Furthermore, 9F23 had no effect on either IL-2-driven proliferation of the Con A-stimulated PBMC or IL-2 binding. Finally, the expression of feline IL-2R alpha on Con A-stimulated PBMC was up-regulated by addition of exogenous IL-2. Thus, 9F23 defines an epitope different from the IL-2 binding site on the alpha-subunit of feline IL-2R.
Ohno
K
K
Laboratory of Immunology, National Institute of Health, Tokyo, Japan.
Goitsuka
R
R
Kitamura
K
K
Hasegawa
A
A
Tokunaga
T
T
Honda
M
M
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D000918:Antibody Specificity; D000941:Antigens / Q000302:isolation & purification; D002415:Cats; D003208:Concanavalin A / Q000494:pharmacology; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D011487:Protein Conformation; D015375:Receptors, Interleukin-2 / Q000737:chemistry / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal; D000941:Antigens; D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D003208:Concanavalin A