Release of soluble transferrin receptor from the surface of human leukemic HL60 cells

37Citations
Citations of this article
6Readers
Mendeley users who have this article in their library.

Abstract

Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4°C. The affinity of Tf for the soluble receptor released by cells (k(d) = 2.3 x 10-10 mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (k(d) = 1.2 x 10-10 mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease.

Cite

CITATION STYLE

APA

Chitambar, C. R., & Zivkovic, Z. (1989). Release of soluble transferrin receptor from the surface of human leukemic HL60 cells. Blood, 74(2), 602–608. https://doi.org/10.1182/blood.v74.2.602.bloodjournal742602

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free