Faculty Collaboration Database

Bioengineered iPSC-derived megakaryocytes for the detection of platelet-specific patient alloantibodies. Blood 2019 Nov 28;134(22):e1-e8

Date

11/08/2019

Pubmed ID

31697836

Pubmed Central ID

PMC6887112

DOI

10.1182/blood.2019002225

Scopus ID

2-s2.0-85075813953 (requires institutional sign-in at Scopus site)   21 Citations

Abstract

Human platelet membrane glycoprotein polymorphisms can be immunogenic in man and are frequently the cause of clinically important immune reactions responsible for disorders such as neonatal alloimmune thrombocytopenia. Platelets from individuals carrying rare polymorphisms are often difficult to obtain, making diagnostic testing and transfusion of matched platelets challenging. In addition, class I HLA antibodies frequently present in maternal sera interfere with the detection of platelet-reactive alloantibodies. Detection of alloantibodies to human platelet antigen 3 (HPA-3) and HPA-9 is especially challenging, in part because of the presence of cell type-specific glycans situated near the polymorphic amino acid that together form the alloepitope. To overcome these limitations, we generated a series of HLA class I-negative blood group O induced pluripotent stem cell (iPSC) lines that were gene edited to sequentially convert their endogenous HPA-3a alloantigenic epitope to HPA-3b, and HPA-9a to HPA-9b. Subjecting these cell lines, upon differentiation into CD41+/CD42b+ human megakaryocytes (MKs), to flow cytometric detection of suspected anti-HPA-3 and HPA-9 alloantisera revealed that the HPA-3a-positive MKs specifically reacted with HPA-3a patient sera, whereas the HPA-3b MKs lost reactivity with HPA-3a patient sera while acquiring reactivity to HPA-3b patient sera. Importantly, HPA-9b-expressing MKs specifically reacted with anti-HPA-9b-suspected patient samples that had been undetectable using conventional techniques. The provision of specialized iPSC-derived human MKs expressing intact homozygous glycoprotein alloantigens on the cell surface that carry the appropriate endogenous carbohydrate moieties should greatly enhance detection of clinically important and rare HPA-specific alloantibodies that, to date, have resisted detection using current methods.

Author List

Zhang N, Santoso S, Aster RH, Curtis BR, Newman PJ

Author

Brian Curtis PhD Director in the Platelet & Neutrophil Immunology Laboratory department at BloodCenter of Wisconsin

MESH terms used to index this publication - Major topics in bold

Antigens, Human Platelet
Cell Engineering
Flow Cytometry
Humans
Induced Pluripotent Stem Cells
Isoantibodies
Megakaryocytes