Two distinct affinity binding sites for IL-1 on human cell lines

Journal Article · Tue Aug 15 04:00:00 EDT 1989 · J. Immunol.; (United States)

OSTI ID:5823085

Bensimon, C; Wakasugi, N; Tagaya, Y; Takakura, K; Yodoi, J; Tursz, T; Wakasugi, H

We used two human cell lines, NK-like YT-C3 and an EBV-containing B cell line, 3B6, as models to study the receptor(s) for IL-1. Two distinct types of saturable binding sites were found on both cell lines at 37 degrees C. Between 1 pM and 100 pM of 125I-IL-1-alpha concentration, saturable binding sites were detected on the YT-C3 cells with a K of 4 x 10(-11) M. The K found for the IL-1-alpha binding sites on 3B6 cells was 7.5 x 10(-11) M. An additional binding curve was detected above 100 pM on YT-C3 cells with a K of 7 x 10(-9) M and on 3B6 cells with a K of 5 x 10(-9) M. Scatchard plot analysis revealed 600 sites/cell with high affinity binding and 7000 sites/cell with low affinity for YT-C3 cells and 300 sites/cell with high affinity binding and 6000 sites/cell with low affinity for 3B6 cells. At 37 degrees C, the internalization of 125I-labeled IL-1 occurred via both high and low affinity IL-1R on both YT-C3 and 3B6 cells, whereas the rates of internalization for high affinity binding sites on YT-C3 cells were predominant in comparison to that of low affinity binding sites. In chemical cross-linking studies of /sup 125/I-IL-1-alpha to 3B6 and YT-C3 cells, two protein bands were immunoprecipitated with Mr around 85 to 90 kDa leading to an estimation of the Mr of the IL-1R around 68 to 72 kDa. In similar experiments, the Mr found for the IL-1R expressed on the murine T cell line EL4 was slightly higher (around 80 kDa). Whether these distinct affinity binding sites are shared by a single molecule or by various chains remains to be elucidated.

• Research Organization: Institut Gustave Roussy, Villejuif (France)
• OSTI ID: 5823085
• Journal Information: J. Immunol.; (United States), Journal Name: J. Immunol.; (United States) Vol. 143:4; ISSN JOIMA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BIOASSAY
BIOCHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CROSS-LINKING
DAYS LIVING RADIOISOTOPES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
GROWTH FACTORS
HEMIC DISEASES
IMMUNE SYSTEM DISEASES
IMMUNOASSAY
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
LEUKEMIA
LYMPHOKINES
MAMMALS
MAN
MEMBRANE PROTEINS
MICE
MITOGENS
NEOPLASMS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
POLYMERIZATION
PRIMATES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RODENTS
TUMOR CELLS
VERTEBRATES