Phenotypic changes in lymphocyte subpopulations in pediatric renal-transplant patients after T-cell depletion.
BACKGROUND
T-cell depletion causes a novel homeostasis in lymphocyte subsets in adult transplant recipients. Little is known about long-term changes in pediatric patients.


METHODS
Twenty-one pediatric renal-transplant patients (mean age 11.8 years) were selected according to their initial postoperative immunosuppressive therapy: (1) baseline immunosuppression (BI) with cyclosporine, azathioprine, and steroids, n=11; and (2) BI plus polyclonal antibodies, n=10. Lymphocyte surface markers were measured in the mean 2.3 years after transplantation and analyzed between the patient groups and in regard to 46 age-matched healthy controls.


RESULTS
The patient groups did not differ with respect to age, sex, renal function, and previous infections. Total lymphocyte counts, CD4+ T-cell numbers, and distribution of naive to memory CD4+ T cells were not different between transplant groups and controls. However, patients with postoperative T-cell depletion showed significantly lower ratios of CD4+ to CD8+ T cells, elevated CD8+ T-cell numbers, increased counts of CD8+ T cells coexpressing CD57, and higher numbers of CD8+ cells with a naive phenotype. In addition, the numbers of double-positive T cells and lymphocytes bearing both natural killer (NK) and T-cell markers were elevated in the patients with postoperative depletion. NK and B-cell counts were lower in the transplant patient groups compared with the healthy controls.


CONCLUSIONS
Pediatric transplant patients show characteristic long-term changes in lymphocyte subsets after T-cell depletion. In contrast with adult patients, these perturbations are less pronounced and predominant in the CD8+ T-cell compartment.
Klaus
Günter
G
Clinic of Pediatrics, Philipps-University, Marburg, Germany.
Mostert
Katharina
K
Reckzeh
Barbara
B
Mueller
Thomas F
TF
D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000097:blood*; D016516:CD4-CD8 Ratio; D002648:Child; D002675:Child, Preschool; D004359:Drug Therapy, Combination; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000145:classification / Q000627:therapeutic use*; D016030:Kidney Transplantation / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion / Q000379:methods*; D016131:Lymphocyte Subsets / Q000276:immunology*; D008214:Lymphocytes / Q000145:classification / Q000276:immunology*; D012016:Reference Values; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors
D015703:Antigens, CD; D007166:Immunosuppressive Agents