High-affinity receptor-mediated internalization and degradation of interleukin 2 in human T cells

• Published in: The Journal of experimental medicine Vol. 163; no. 3; pp. 550 - 562
• Main Authors: FUJII, M, SUGAMURA, K, SANO, K, NAKAI, M, SUGITA, K, HINUMA, Y
• Format: Journal Article
• Language: English
• Published: New York, NY Rockefeller University Press 01.03.1986; The Rockefeller University Press
• Subjects: AIDS/HIV; Analysis of the immune response. Humoral and cellular immunity; Biological and medical sciences; Cell Compartmentation; Cell Line; Cell Transformation, Viral; Deltaretrovirus; Endocytosis; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Hydrogen-Ion Concentration; Immunobiology; Interleukin-2 - metabolism; Kinetics; Lymphokines, interleukins ( function, expression); Receptors, Immunologic - metabolism; Receptors, Interleukin-2; Regulatory factors and their cellular receptors; T-Lymphocytes - metabolism; Temperature; Human; Cell nucleus; Retroviridae; Lymphokine; Virus; Degradation; Membrane receptor; Cell line; Interleukin 2; Internalization; T-Lymphocyte; Affinity; HTLV-I virus
• ISSN: 0022-1007; 1540-9538
• DOI: 10.1084/jem.163.3.550

Receptor-mediated internalization and degradation of IL-2 were investigated in cell lines carrying human T cell leukemia/lymphoma (lymphotrophic) virus type I (HTLV-I) and PHA-treated normal PBL. The HTLV-I-carrying cell lines ILT-Yan and TL-Mor, and the PBL expressed both high- and low-affinity IL-2-R. However, another HTLV-I-carrying T cell line, MT-1, expressed mainly low-affinity receptors. Greater than 50% of the IL-2 bound to high-affinity receptors was internalized within 10 min when these cells were incubated at 37 degrees C. The internalized IL-2 was rapidly degraded and the products were excreted into the culture fluid. The t1/2 of IL-2 degradation in these cells was estimated as 60-80 min at 37 degrees C. The internalization and degradation of IL-2 were both temperature dependent. Light-microscopic autoradiography with 3H-labeled IL-2 confirmed the internalization of IL-2, and suggested that some IL-2 might be carried to the nucleus.