title: Up-regulation of interleukin 4 receptor expression on immature (Lyt-2-/L3T4-) thymocytes.
abstract: In this report, the effect of interleukin 4 (IL-4) on the growth and differentiation of Lyt-2-/L3T4-(2-4-) thymocytes was investigated. It was found that these thymocytes proliferated extensively when cultured in the presence of IL-4 + phorbol myristate acetate without apparent differentiation to Lyt-2+ or L3T4+ cells. We also demonstrated that 2-4- thymocytes constitutively express a high affinity (dissociation constant of 20 to 40 pM) receptor for IL-4. Freshly isolated 2-4- thymocytes expressed on average about 100 IL-4 receptors per cell, but the number of receptors increased approximately 8-fold within 3 days after activation by IL-4 + phorbol myristate acetate. These findings suggest that IL-4 may play an important role in T cell ontogeny by promoting self-renewal of stem cells within the thymus.
authors.affiliation: Department of Immunology, DNAX Research Institute, Palo Alto, CA 94304.
authors.forename: J W
authors.initials: JW
authors.lastname: Lowenthal
authors.forename: J
authors.initials: J
authors.lastname: Ransom
authors.forename: M
authors.initials: M
authors.lastname: Howard
authors.forename: A
authors.initials: A
authors.lastname: Zlotnik
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D002453:Cell Cycle; D002454:Cell Differentiation; D015847:Interleukin-4; D007378:Interleukins / Q000378:metabolism*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D010641:Phenotype; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000032:analysis / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D007378:Interleukins; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D015847:Interleukin-4