title: Involvement of CD23/Fc epsilon RII in the homotypic and heterotypic cytoadhesion of the human eosinophilic cell line Eol-3.
abstract: A subclone of the EoL-3 human eosinophilic leukemia cell line (EoL-3.12) was selected for its high inducibility of CD23 (low affinity IgE receptor/Fc epsilon RII) by IL-4. Maximum membrane CD23 expression was detected after 16 h of incubation with IL-4, then gradually returned to basal level after 48 h. Membrane expression of CD23 on EoL-3.12 cells was found to parallel their homotypic aggregation. Extending the time of incubation with IL-4 to 48 h or more resulted in a de-aggregation of cells of cells with a shedding of membrane CD23 and an increase of its soluble form, sCD23. The IL-4-induced aggregation of EoL-3.12 cells was inhibited with anti-CD23 antibody or human myeloma IgE protein, indicating that it was mediated through the engagement of CD23. EoL3.12 incubated with IL-4 displayed morphological changes associated with differentiation, such as an increased number of lobulated nuclei with prominent nucleoli, increased ratio of cytoplasm and distinct cytoplasmic processes. EoL-3.12 cells incubated with IL-4 also displayed an enhanced adherence to human umbilical vein endothelial cells (HUVEC), which was reverted when the IL-4 incubation time extended. Furthermore, the transendothelial migration of EoL-3.12 cells toward a chemokinetic gradient of soluble CD23 (sCD23; 29 kDa fragment) closely paralleled the density of membrane CD23 expressed on EoL-3.12 cells. Additionally, the engagement of CD23 led to the activation of the L-arginine-dependent pathway of nitric oxide (NO) production, as detected by the increase in intracytoplasmic cGMP concentration. The capacity of EoL-3.12 cells to form homotypic as well as heterotypic adhesion appears therefore to be regulated, at least in part, by the level of CD23 expression.
authors.affiliation: U 365 INSERM, Interférons et Cytokines, Institut Curie, Paris, France.
authors.forename: K A
authors.initials: KA
authors.lastname: Yamaoka
authors.forename: J P
authors.initials: JP
authors.lastname: Kolb
mesh_terms: D001120:Arginine / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D006152:Cyclic GMP / Q000096:biosynthesis; D004730:Endothelium, Vascular / Q000166:cytology; D004804:Eosinophils / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D007073:Immunoglobulin E / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D015472:Leukemia, Eosinophilic, Acute / Q000473:pathology; D009194:Myeloma Proteins / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000502:physiology; D009569:Nitric Oxide / Q000096:biosynthesis; D009928:Organ Specificity; D017455:Receptors, IgE / Q000502:physiology*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014471:Umbilical Veins
chemical_list: D009194:Myeloma Proteins; D009363:Neoplasm Proteins; D017455:Receptors, IgE; D015847:Interleukin-4; D009569:Nitric Oxide; D007073:Immunoglobulin E; D001120:Arginine; D006152:Cyclic GMP