Cytolytic function of clonable T cells after human bone marrow transplantation.
We evaluated T-cell mediated lymphokine activated killer (LAK) function during the late (greater than 5 months) reconstitution phase after T cell-depleted allogeneic bone marrow transplantation (BMT) for hematologic malignancy. Since LAK cells are sustained by interleukin-2 (IL-2), we also investigated the ability of post-BMT T cells to produce IL-2. These functions were investigated at the clonal level. More than 200 T-cell clones from six long-term BMT recipients were generated and compared with 60 T-cell clones derived from two normal controls. Almost all the CD8+ clonal cultures from BMT recipients expressed cytolytic activity in a lectin-dependent cellular cytoxicity assay. Interestingly, a higher proportion of BMT recipient-derived cytolytic clones were able to mediate LAK activity in comparison with control clones (28% versus 4%, P less than .05). However, T-cell clones from BMT recipients, as opposed to control clones, were largely incapable of producing IL-2. Given the high proportions of post-BMT circulating CD8+ T cells, it appears that, in long-term BMT recipients, the precursors of nonspecific LAK effectors are present at above normal levels. However, their function may be defective in vivo due to poor IL-2 production.
Velardi
A
A
Department of Internal Medicine, University of Perugia, Italy.
Varese
P
P
Grossi
C E
CE
Albi
N
N
Dembech
C
C
Terenzi
A
A
Moretta
L
L
Grignani
F
F
Martelli
M F
MF
Mingari
M C
MC
D016026:Bone Marrow Transplantation / Q000473:pathology / Q000502:physiology*; D002999:Clone Cells / Q000502:physiology; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism; D015979:Killer Cells, Lymphokine-Activated / Q000502:physiology; D010641:Phenotype; D013601:T-Lymphocytes / Q000378:metabolism / Q000502:physiology*; D013602:T-Lymphocytes, Cytotoxic / Q000502:physiology*
D007376:Interleukin-2