title: Early CD3+/CD15+ peripheral blood leukocyte chimerism patterns correlate with long-term engraftment in non-malignant hematopoietic SCT.
abstract: Following hematopoietic SCT (HSCT) for non-malignant disorders (NMDs) variable donor chimerism among lympho-hematopoietic lines may be observed. We retrospectively evaluated early post-HSCT, lineage-sorted (CD3+ and CD15+) peripheral blood leukocyte chimerism data to characterize patterns and assess for association with long-term CD15+ engraftment. 'Early' was defined as the first value obtained between days +14 and +42, 'late' as the last recorded value after day +90. 'High' donor chimerism was defined as 80% on either fraction at all time-points. Patients were classified into four subgroups with respect to early CD3+/CD15+ chimerism patterns (high/low) then analyzed for long-term CD15+ chimerism status. A total of 135 transplants were evaluable, with all three time-points available in 97. Underlying disease, graft source, patient age and conditioning intensity varied. 'Split' early chimerism (discordant high/low CD3+/CD15+ status) was common. Multivariable analysis revealed strong association between conditioning regimen and primary disease on early CD3+/CD15+ chimerism patterns and a dominant predictive effect of early CD15+ chimerism on long-term CD15+ donor engraftment (observed at median day +365). These data may guide real-time clinician decisions (restraint vs intervention, when available) when faced with unfavorable or unusual early lympho-hematopoietic chimerism patterns following HSCT for NMD.
authors.affiliation: Internal Medicine/Pediatrics, University of Minnesota, Minneapolis, MN, USA.
authors.forename: T G
authors.initials: TG
authors.lastname: Ketterl
authors.affiliation: Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN, USA.
authors.forename: M
authors.initials: M
authors.lastname: Flesher
authors.affiliation: Biostatistics and Bioinformatics Core, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA.
authors.forename: R
authors.initials: R
authors.lastname: Shanley
authors.affiliation: Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN, USA.
authors.forename: W
authors.initials: W
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D017252:CD3 Complex / Q000097:blood* / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D016256:Lewis X Antigen / Q000097:blood* / Q000276:immunology; D008297:Male; D018183:Transplantation Chimera / Q000097:blood* / Q000276:immunology; D014184:Transplantation, Homologous / Q000379:methods*; D055815:Young Adult
chemical_list: D017252:CD3 Complex; D016256:Lewis X Antigen