These authors contributed equally to the work presented in this paper. This work was supported by a National Science and Engineering Research Council scholarship to JAM and by Canadian Blood Services infrastructure grant TO22656.
Antibody-mediated glycophorin C coligation on K562 cells induces phosphatidylserine exposure and cell death in an atypical apoptotic process
Article first published online: 24 DEC 2012
© 2012 American Association of Blood Banks
Volume 53, Issue 10, pages 2134–2140, October 2013
How to Cite
Wang, D., Seto, E., Shu, J., Micieli, J. A., Fernandes, B. J. and Denomme, G. A. (2013), Antibody-mediated glycophorin C coligation on K562 cells induces phosphatidylserine exposure and cell death in an atypical apoptotic process. Transfusion, 53: 2134–2140. doi: 10.1111/trf.12028
- Issue published online: 4 OCT 2013
- Article first published online: 24 DEC 2012
- Manuscript Accepted: 31 OCT 2012
- Manuscript Revised: 26 SEP 2012
- Manuscript Received: 10 FEB 2012
Glycophorin C (GPC) is necessary in the maintenance of red blood cell structure. Severe autoimmune hemolytic anemia and hemolytic disease of the fetus and newborn (HDFN) have been associated with Gerbich (Ge) blood group system antigens expressed on GPC. Previous in vitro studies with cord blood progenitor cells have shown that anti-Ge suppresses erythropoiesis.
Study Design and Methods
Here, we evaluated the K562 erythroleukemic cell line to study the cellular effects of a murine anti-GPC. Cell proliferation was evaluated after treatment with anti-GPC. Flow cytometry was used to evaluate exofacial phosphatidylserine (PS) expression and cell viability (propidium iodide binding). Cell morphology was evaluated under light microscopy with cytospin preparations stained with May-Grünwald Giemsa.
Anti-GPC dramatically inhibited K562 proliferation and increased PS expression, consistent with cytoplasmic blebbing, suggesting evidence of apoptosis. Z-VAD-FMK, an inhibitor of classical apoptosis, was unable to reverse the suppressive effect of anti-GPC. However, hemin was able to attenuate growth suppression.
Together, the data suggest that anti-GPC suppresses erythroid proliferation through the induction of nonclassical apoptosis.