{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T05:05:03Z","timestamp":1784005503145,"version":"3.55.0"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:sec>\n                    <jats:title>Purposed<\/jats:title>\n                    <jats:p>Natural Killer cell kinetics and Killer-cell immunoglobulin-like receptors (KIRs) are increasingly recognized for their role during allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the prognostic impact of donor KIR haplotype configurations on patient survival remains controversial. To clarify this relationship, we conducted a systematic review and meta-analysis evaluating the impact of donor KIR haplotypes on the survival of patients undergoing allo-HSCT.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We systematically searched PubMed, Embase, the Cochrane Library, and CBM. Data were analyzed using RevMan5.4. Pooled hazard ratio (HR) for time-to-event data. Subgroup analyses were performed for sample size, area, donor type, T cell replete or deplete, GVHD prophylaxis, and lymphoid or myeloid.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>17 eligible studies were included, and meta-analysis showed that donor KIR B\/X genotype is associated with significantly superior overall survival (HR = 0.68, 95%CI, 0.56-0.82; P&amp;lt;0.0001), reduced relapse incidence (HR = 0.61, 95%CI, 0.44-0.85; P = 0.003), and improved relapse-free survival (HR = 0.61, 95%CI, 0.46-0.81; P = 0.0008).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>The findings suggest that donor KIR B\/X haplotype is associated with favorable survival outcomes in allo-HSCT including HLA-matched sibling, unrelated donor, and haploidentical transplantation, supporting its potential utility as a reference biomarker for donor selection.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fimmu.2026.1856878","type":"journal-article","created":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T04:21:50Z","timestamp":1784002910000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of donor killer-cell immunoglobulin-like receptor genotypes on clinical outcome after allogeneic hematopoietic stem cell transplantation\u2014a systematic review and meta-analysis"],"prefix":"10.3389","volume":"17","author":[{"given":"Yarui","family":"Huang","sequence":"first","affiliation":[{"name":"Center for Hematology, Southwest Hospital, Third Military Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qingrong","family":"Li","sequence":"additional","affiliation":[{"name":"Center for Hematology, Southwest Hospital, Third 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