Erythroid-lineage-specific engraftment in patients with severe hemoglobinopathy following allogeneic hematopoietic stem cell transplantation.
OBJECTIVE
We aimed to create a molecular assay to monitor erythroid (red blood cell [RBC]) engraftment in any patient following allogeneic hematopoietic stem cell transplantation, independent of disease-specific mutations.


METHODS
We identified 10 common single nucleotide polymorphisms (SNPs), expressed by genes encoding RBC antigens and structural proteins. These SNPs were polymerase chain reaction-amplified from total RNA extracted from peripheral blood, which contains nucleated erythroid progenitors. Mixing studies validated that each SNP can quantitatively measure donor/recipient DNA and RNA.


RESULTS
We directly genotyped 23 patients who underwent hematopoietic stem cell transplantation and their human leukocyte antigen-matched donors and found a median of three informative SNPs (i.e., discordant between donor and recipient) per pair. By using the informative RBC SNPs to quantify donor-derived RBC transcripts, we compared rates of RBC engraftment in 13 patients with hemoglobinopathies vs donor mononuclear cell (white blood cell [WBC]) engraftment. Consistent with known ineffective erythropoiesis associated with hemoglobinopathies, we detected up to threefold greater RBC-specific compared to overall WBC engraftment in five of eight patients who were mixed chimeras by transplant day 30. The remaining three of eight who received ABH-incompatible grafts, demonstrated at least 0.5-fold lower RBC compared to WBC engraftment that was related to persistence of host-derived anti-isohemagglutinin antibodies.


CONCLUSIONS
This RNA-based assay can be used to monitor RBC-specific engraftment regardless of a patient's specific hemoglobin mutation or even diagnosis. We propose that panels of expressed SNPs informative for other cell lineages can be created to comprehensively assess the impact of novel stem cell-based therapies on lineage-specific engraftment.
Department of Medical Oncology, M.D. Anderson Cancer Center, Houston, TX, USA.
Paul M
PM
Armistead
Mehrdad
M
Mohseni
Roslyn
R
Gerwin
Emily C
EC
Walsh
Masoud
M
Iravani
Bahram
B
Chahardouli
Shahrbano
S
Rostami
Wandi
W
Zhang
Donna
D
Neuberg
John
J
Rioux
Ardeshir
A
Ghavamzadeh
Jerome
J
Ritz
Joseph H
JH
Antin
Catherine J
CJ
Wu
D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000097:blood / Q000601:surgery*; D001787:Blood Group Incompatibility; D001798:Blood Proteins / Q000235:genetics; D019070:Cell Lineage; D002648:Child; D002675:Child, Preschool; D041905:Erythroid Cells / Q000166:cytology*; D004920:Erythropoiesis; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency; D005819:Genetic Markers; D005838:Genotype; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis; D006085:Graft Survival; D019337:Hematologic Neoplasms / Q000097:blood / Q000601:surgery; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012680:Sensitivity and Specificity; D014184:Transplantation, Homologous; D017086:beta-Thalassemia / Q000097:blood / Q000601:surgery*
D001798:Blood Proteins; D005819:Genetic Markers