Reconstitution of maturating and regulatory lymphocyte subsets after cord blood and BMT in children

• Published in: Bone marrow transplantation (Basingstoke) Vol. 48; no. 3; pp. 376 - 382
• Main Authors: Charrier, E, Cordeiro, P, Brito, R-M, Mezziani, S, Herblot, S, Le Deist, F, Duval, M
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-03-2013; Nature Publishing Group
• Subjects: 631/250/1619; 631/250/1904; 692/700/1720; Adolescent; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Blood; Bone marrow; Bone marrow transplantation; Bone Marrow Transplantation - methods; Bone marrow, stem cells transplantation. Graft versus host reaction; CD25 antigen; CD27 antigen; CD4 antigen; CD45RA antigen; CD8 antigen; Cell Biology; Child; Children; Cohort Studies; Cord blood; Female; Fetal Blood - immunology; Fetal Blood - transplantation; Foxp3 protein; Graft-versus-host reaction; Health aspects; Hematology; Humans; Immune reconstitution; Immune response; Immunological tolerance; Immunoregulation; Internal Medicine; Killer cell immunoglobulin-like receptors; Killer Cells, Natural - cytology; Killer Cells, Natural - immunology; Leukemia - blood; Leukemia - pathology; Leukemia - surgery; Lymphocyte Subsets - cytology; Lymphocytes; Lymphocytes - cytology; Lymphocytes - immunology; Lymphocytes B; Lymphocytes T; Male; Medical sciences; Medicine; Medicine & Public Health; Memory cells; Natural killer cells; NKG2 antigen; original-article; Public Health; Recovery; Stem cell transplantation; Stem Cells; T-Lymphocytes, Regulatory - cytology; T-Lymphocytes, Regulatory - immunology; Thymus; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Transplantation; Transplants & implants; Tumors; BMT; immune reconstitution; thymopoiesis; cord blood transplantation; lymphocyte subpopulations; Human; Lymphopoiesis; Hematology; Stem cell; Hematopoietic cell; Homograft; Immune reconstitution; Cell subpopulation; Blood; Thymopoiesis; Blood cell; Bone marrow; Graft; Reconstitution; Umbilical cord; Child; Lymphocyte; Regulatory cell
• ISSN: 0268-3369; 1476-5365
• DOI: 10.1038/bmt.2012.176

Some clinical characteristics of cord blood transplantation (CBT) might be explained by specificities in the reconstitution of immune subsets differing by their maturation stage or their implication in GVHD, tolerance or immune responses against tumor or infectious agents. Here, we compare the immune reconstitution of several of these subsets after CBT and BMT. B-cell count recovery was faster after CBT. There was no difference in the recovery of CD4
+
and CD8
+
cell counts. There was no difference either in the frequency of several subsets: CD45RO
+
memory, and CD45RA
+
naïve cells within the CD4
+
T-cell compartment, CD27
+
among B cells, CD56
bright
, NKG2A
+
, and KIR
+
cells among natural killer (NK) cells, CD25
+
FOXP3
+
regulatory T cells and invariant NKT cells. The proportion of the thymic naïve CD31
+
CD45RA
+
CD4
+
T cells was lower after CBT at 6 months post-transplant, and was still below normal at 1 year in both groups. NK-cell expansion was more sustained after CBT, with fewer double-negative NKG2A
−
KIR
−
hyporesponsive cells and more double-positive NKG2A
+
KIR
+
hyper-responsive NK cells. These results, therefore, indicate that further research to improve CBT outcome should try to improve thymopoieisis and take advantage of the sustained NK-cell reconstitution.