Long-term T-cell reconstitution after hematopoietic stem-cell transplantation in primary T-cell-immunodeficient patients is associated with myeloid chimerism and possibly the primary disease phenotype.
We studied T-cell reconstitution in 31 primary T-cell-immunodeficient patients who had undergone hematopoietic stem-cell transplantation (HSCT) over 10 years previously. In 19 patients, there was no evidence of myeloid chimerism because little or no myeloablation had been performed. Given this context, we sought factors associated with good long-term T-cell reconstitution. We found that all patients having undergone full myeloablation had donor myeloid cells and persistent thymopoiesis, as evidenced by the presence of naive T cells carrying T-cell receptor excision circles (TRECs). In 9 patients with host myeloid chimerism, sustained thymic output was also observed and appeared to be associated with gammac deficiency. It is therefore possible that the complete absence of thymic progenitors characterizing this condition created a more favorable environment for thymic seeding by a population of early progenitor cells with the potential for self-renewal, thus enabling long-term (> 10 years) T-cell production.
Cavazzana-Calvo
Marina
M
Institut National de la Santé et de la Recherche Médicale, Unité 768, Paris, France.
Carlier
Frédérique
F
Le Deist
Françoise
F
Morillon
Estelle
E
Taupin
Pierre
P
Gautier
David
D
Radford-Weiss
Isabelle
I
Caillat-Zucman
Sophie
S
Neven
Bénédicte
B
Blanche
Stephane
S
Cheynier
Rémi
R
Fischer
Alain
A
Hacein-Bey-Abina
Salima
S
D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007223:Infant; D015458:Leukemia, T-Cell / Q000097:blood / Q000276:immunology / Q000628:therapy; D038041:Lymphopoiesis / Q000276:immunology / Q000502:physiology*; D008297:Male; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology / Q000502:physiology; D013995:Time; D018183:Transplantation Chimera / Q000097:blood* / Q000276:immunology
D011948:Receptors, Antigen, T-Cell