{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T05:21:00Z","timestamp":1787721660474,"version":"build-2784847793"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T00:00:00Z","timestamp":1787702400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005972","name":"Deutsche Krebshilfe","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100005972","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Sequential conditioning allogeneic hematopoietic stem cell transplantation (allo-HSCT) regimens might offer improved disease control in high-risk myeloid patients. But concerns remain regarding toxicity, infection risk and delayed immune reconstitution (IR), particularly in older and HLA-haploidentical transplant recipients. To address these concerns, we comprehensively compared safety, feasibility and clinical outcome across HLA-matched related (MRD), matched unrelated (MUD) and haploidentical donor (Haplo) HSCT and longitudinally characterize IR patterns and their associations with post-transplant outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective matched-pair analysis comparing MRD-, matched MUD- and Haplo-HSCT in elderly patients matched for (1) disease activity: p = 1.0; (2) disease status: p = 1.0; (3) modified disease risk index (DRI): p = 0.9; (4) hematopoietic cell transplantation comorbidity index (HCT-CI): p =  0.92; and (5) age: p = 0.95. Outcomes included disease-free (DFS) and overall survival (OS), relapse, non-relapse mortality (NRM), graft-versus-host disease (GvHD), toxicity, infections, and donor-specific IR dynamics and their impact on clinical outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>With a median follow-up of more than 9 years, no significant differences were observed in long-term disease control and survival among the three groups (5-y DFS\/OS: MRD\u00a0=\u00a041%\/41%, MUD\u00a0=\u00a056%\/63%, Haplo = 58%\/58%; p = 0.52\/0.55). Cumulative incidences (CI) of 5-y-NRM and 1-y moderate and severe chronic GvHD (cGvHD) rates were comparable among the three groups (NRM\/cGvHD: MRD\u00a0=\u00a019%\/13%, MUD\u00a0=\u00a029%\/6%, Haplo = 18%\/19%; p = 0.3\/0.57). Overall immune cell recovery after one year was comparable among groups, though early recovery of CD3+ T and NK cells was delayed after Haplo-HSCT. Subgroup analysis revealed that higher early CD4+ T and lower B cell counts were associated with increased CI of acute GvHD III-IV\u00b0 (p = 0.04\/0.03). Additionally, NK recovery at one year was associated with improved DFS and OS as well as lower relapse incidence.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Sequential therapy is safe and feasible in elderly patients with high-risk or active disease across all three transplant platforms. The observed associations between IR and clinical outcomes highlight the relevance of immune monitoring for anticipating post-transplant complications and guiding individualized prophylactic and therapeutic strategies. Prospective studies are needed to further investigate these findings and define the underlying mechanisms.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fimmu.2026.1803250","type":"journal-article","created":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T04:52:52Z","timestamp":1787719972000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Sequential conditioning in hematopoietic stem cell transplantation in elderly high-risk myeloid blood cancer patients: long-term survival, disease control, and immune recovery across donor types in a matched-pair analysis"],"prefix":"10.3389","volume":"17","author":[{"given":"Sarah","family":"Haebe","sequence":"first","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Stauffer","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heidrun","family":"Drolle","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dusan","family":"Prevalsek","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moritz","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quentin","family":"Fichaux","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Weigand","sequence":"additional","affiliation":[{"name":"Institute of Laboratory Medicine, Ludwig Maximilian University Hospital","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessia","family":"Fraccaroli","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johanna","family":"Tischer","sequence":"additional","affiliation":[{"name":"Department of Medicine III, Ludwig Maximilian University Hospital Munich","place":["Munich, 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