Characterization of high-affinity receptors for interleukin 5 on interleukin 5-dependent cell lines.
Interleukin 5 (IL-5) is a glycosylated polypeptide that acts as a key factor for B-cell growth and differentiation. We demonstrated previously that there are two classes (high and low affinity) of IL-5 receptors on murine chronic B-cell leukemic cells (BCL1-B20). Treatment of surface-bound radiolabeled IL-5 with bivalent crosslinkers identified a polypeptide of Mr 92,500. In this study, we analyzed characteristics of high-affinity IL-5 receptors on IL-5-dependent early B-cell lines (T-88 and T88-M), mouse myeloma cells (MOPC-104E), and BCL1-B20 cells. All cell lines had two classes of IL-5 binding sites, but T88-M cells bore the highest number of high-affinity receptors. The number of high-affinity IL-5 receptors on BCL1-B20 cells could be up-regulated 3-fold by lipopolysaccharide and down-regulated by IL-5. Disuccinimidyl tartarate crosslinking of 35S-labeled IL-5 to the receptors on the T88-M and lipopolysaccharide-stimulated BCL1-B20 cells revealed two major 35S-labeled components of Mr 92,500 and Mr 160,000, even when the binding of 35S-labeled IL-5 was carried out under high-affinity conditions (100 pM 35S-labeled IL-5). The Mr 92,500 component, but not the Mr 160,000 component, was detected in the lysates of MOPC-104E and T-88 cells, both of which bore a large number of low-affinity receptors and a limited number of high-affinity receptors. The results suggest that the Mr 92,500 component represents the complex of IL-5 with the low-affinity Mr 46,500 receptor, whereas the high-affinity receptor consists of the Mr 46,500 peptide and an additional peptide.
Mita
S
S
Department of Biology, Kumamoto University Medical School, Japan.
Tominaga
A
A
Hitoshi
Y
Y
Sakamoto
K
K
Honjo
T
T
Akagi
M
M
Kikuchi
Y
Y
Yamaguchi
N
N
Takatsu
K
K
D000276:Adjuvants, Immunologic; D000818:Animals; D002460:Cell Line; D003432:Cross-Linking Reagents / Q000378:metabolism; D015848:Interleukin-5; D007378:Interleukins / Q000032:analysis / Q000276:immunology*; D007700:Kinetics; D007942:Leukemia, Experimental; D051379:Mice; D008970:Molecular Weight; D011971:Receptors, Immunologic / Q000302:isolation & purification / Q000378:metabolism*; D018123:Receptors, Interleukin; D053649:Receptors, Interleukin-5
D000276:Adjuvants, Immunologic; D003432:Cross-Linking Reagents; D015848:Interleukin-5; D007378:Interleukins; D011971:Receptors, Immunologic; D018123:Receptors, Interleukin; D053649:Receptors, Interleukin-5