Early recovery of CD4+ T lymphocytes in children on highly active antiretroviral therapy. Dutch study group for children with HIV infections.
BACKGROUND
Regeneration of CD4+ T lymphocytes has been shown to be thymus-dependent in bone marrow transplant recipients and after intensive chemotherapy. The rate of CD4+ T cell regeneration is correlated positively with enlargement of the thymus, as shown on radiographs, and higher rates of CD4+ T lymphocyte regeneration were observed in children as compared with adults, consistent with thymic function diminishing with age. We hypothesized that in HIV infected patients CD4+ T cell recovery during highly active antiretroviral therapy (HAART) may also be thymus dependent. Therefore, repopulation of naive (CD45RA+), memory (CD45RO+) and total CD4+ T lymphocytes and total CD8+ T lymphocytes in peripheral blood was assessed in 13 HIV infected children during the initial 3 months of HAART.


RESULTS
Significantly higher recovery rates of naive, memory and total CD4+ T cells were observed in children below the age of 3 years as compared with older children. Kinetics of total CD8+ T cells showed no relation to age. Moreover, recovery rates of naive CD4+ T cells in patients below 3 years of age were 10-40 fold higher as compared with previously reported naive CD4+ T cell recovery rates in adults on HAART.


CONCLUSIONS
High recovery rates of naive, memory and total CD4+ T cells can be achieved in children below 3 years of age. Changes in CD8 counts did not correlate with age. These results indicate that regeneration of CD4+ T cells during HAART may be a thymus-dependent process.
Cohen Stuart
J W
JW
Department of Virology, Eijkman-Winkler Institute, University Hospital Utrecht, The Netherlands.
Slieker
W A
WA
Rijkers
G T
GT
Noest
A
A
Boucher
C A
CA
Suur
M H
MH
de Boer
R
R
Geelen
S P
SP
Scherpbier
H J
HJ
Hartwig
N G
NG
Hooijkaas
H
H
Roos
M T
MT
de Graeff-Meeder
B
B
de Groot
R
R
D000293:Adolescent; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005434:Flow Cytometry; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D006801:Humans; D007223:Infant; D010641:Phenotype; D012367:RNA, Viral / Q000097:blood; D013997:Time Factors; D019562:Viral Load
D000911:Antibodies, Monoclonal; D012367:RNA, Viral