Analysis of immune reconstitution in children undergoing cord blood transplantation.
OBJECTIVE
The aim of this study was to investigate and compare immune reconstitution in allogeneic cord blood transplantation (CBT) and bone marrow transplantation (BMT) recipients.


METHODS
Twenty-three children underwent CBT from either human leukocyte antigen-identical siblings (11 cases) or unrelated donors (12 cases) were enrolled in the study, together with 23 matched children receiving BMT. Patients were analyzed 2-3 and 12-15 months after transplant. Recovery of T-, B-, and NK-lymphocyte subsets, proliferative in vitro response to mitogens, as well as cytotoxic activities, were investigated.


RESULTS
CBT recipients showed a marked increase in the number of B lymphocytes as compared with patients who underwent BMT (p < 0.001). The absolute number of CD3(+) and CD8(+) T cells, as well as the proliferative response to T-cell mitogens, recovered with time after transplantation, irrespective of the source of stem cells used. Recipients of unrelated CBT had a better recovery of CD4(+) T lymphocytes (p < 0.01). Among patients experiencing acute graft-versus-host disease (GVHD), children given CBT had a much greater production of CD4(+) CD45RA(+) T cells than BMT recipients (p < 0.005). Recovery of NK cell number and innate cytotoxic activities was fast, irrespective of the source of stem cells used.


CONCLUSIONS
Despite the much lower number of lymphocytes transferred with the graft, recovery of lymphocyte number and function toward normal in CBT recipients was rapid and comparable to that observed after transplantation of bone marrow progenitors. This prompt immune recovery possibly was favored by the reduced incidence and severity of GVHD observed in children who underwent CBT.
Department of Pediatrics, University of Pavia, IRCCS Policlinico San Matteo, Pavia, Italy.
A
A
Moretta
R
R
Maccario
F
F
Fagioli
E
E
Giraldi
A
A
Busca
D
D
Montagna
R
R
Miniero
P
P
Comoli
G
G
Giorgiani
M
M
Zecca
S
S
Pagani
F
F
Locatelli
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D001855:Bone Marrow Diseases / Q000628:therapy; D016026:Bone Marrow Transplantation / Q000009:adverse effects; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D005500:Follow-Up Studies; D006085:Graft Survival; D006086:Graft vs Host Disease / Q000209:etiology / Q000276:immunology / Q000517:prevention & control; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects; D006801:Humans; D016130:Immunophenotyping; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology / Q000473:pathology; D008297:Male; D009369:Neoplasms / Q000628:therapy; D009679:Nuclear Family; D014019:Tissue Donors; D019172:Transplantation Conditioning; D014184:Transplantation, Homologous / Q000009:adverse effects; D016896:Treatment Outcome
D015703:Antigens, CD; D007166:Immunosuppressive Agents