Reconstitution of lymphocyte subpopulations in children with inherited metabolic storage diseases after haematopoietic cell transplantation.
We prospectively evaluated the reconstitution of lymphocyte subpopulations in nine children with lysosomal diseases who underwent 11 allogeneic haematopoietic cell transplants (HCTs) following CD34(+) immunomagnetic enrichment, limited T-cell addback and in vivo B-cell depletion. Absolute lymphocyte count recovery was slow to cross the 5th percentile, occurring at a median of 10 months after HCT in patients with full chimaerism. Natural killer cells represented up to 90% of the total lymphoid population during the first 3 months. CD4(+) lymphocyte recovery occurred 9-18 months after HCT. In most patients, CD8(+) lymphocyte recovery was slow and comparable with that of CD4(+) lymphocytes. The CD4(+)/CD8(+) ratio normalised by 3-7 months after HCT in 50% of the patients. CD8(+) lymphocyte recovery was enhanced in patients with viral reactivation. Reconstitution of B-lymphocytes was particularly delayed in patients treated with rituximab. Declining chimaerism, rejection and viral reactivation were the most common problems in our series. Because of the unique graft manipulation, the pace of lymphocyte reconstitution was particularly slow, suggesting that these patients are at a significantly increased risk of infections for up to 2 years after HCT.
Corti
Paola
P
Clinica Pediatrica, Università di Milano-Bicocca, Ospedale San Gerardo, Monza, Italy.
Peters
Charles
C
Balduzzi
Adriana
A
Bertagnolio
Barbara
B
Biondi
Andrea
A
Bugarin
Cristina
C
Dassi
Maria
M
Furlan
Francesca
F
Gaipa
Giuseppe
G
Longoni
Daniela
D
Maglia
Oscar
O
Parini
Rossella
R
Perseghin
Paolo
P
Uderzo
Cornelio
C
Uziel
Graziella
G
Masera
Giuseppe
G
Rovelli
Attilio
A
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006650:Histocompatibility Testing; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods; D007223:Infant; D007694:Killer Cells, Natural / Q000276:immunology; D007965:Leukodystrophy, Globoid Cell / Q000276:immunology / Q000628:therapy; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology*; D016464:Lysosomal Storage Diseases / Q000276:immunology* / Q000628:therapy*; D008297:Male; D009083:Mucopolysaccharidoses / Q000276:immunology / Q000628:therapy; D011446:Prospective Studies; D018183:Transplantation Chimera / Q000276:immunology