In:
Blood, American Society of Hematology, Vol. 100, No. 10 ( 2002-11-15), p. 3639-3645
Abstract:
Evidence suggests that T lymphocyte–mediated inhibition of hematopoiesis in myelodysplastic syndrome (MDS) contributes to cytopenia in some patients and can be reversed by treatment with immunosuppression. We examined the T-cell repertoires of 12 patients with MDS before and after antithymocyte globulin (ATG)–based treatment by T-cell receptor Vβ (TCR-Vβ) spectratype analysis. The average number of TCR-Vβ families with skewed spectratypes, representative of clonal or oligoclonal T-cell populations, was 7.6 in MDS patients before treatment and 3.2 in healthy controls (P = .02). Four patients who recovered effective hematopoiesis after treatment lost prominent, skewed peaks on their spectratypes, suggesting loss or diminution of overrepresented clonal T-cell populations. In contrast, patients who did not recover effective hematopoiesis showed persistently skewed repertoires 3 to 6 months after treatment. In 3 patients with skewed repertoires, cDNA from the complementarity-determining region 3 (CDR3) of 4 TCR-Vβ families was cloned and repetitively sequenced, confirming clonal T-cell dominance in each family. In one nonresponder, 16 of 19 CDR3 sequences were identical, demonstrating that 9.3% of the total T-cell population was made up of a single clone. By 6 months after treatment, this clone persisted on both spectratype and DNA sequence complementarity and when analyzed by flow cytometry was shown to be CD8+/CD45RA+/HLA-DR−. T-cell clones were not anergic because they could be expanded 4-fold in vitro. Our results demonstrate that predominant clonal T cells that appear to be antigen-driven persist in patients with MDS unresponsive to immunosuppression, but predominant clones regress in responders to immunosuppression.
Type of Medium:
Online Resource
ISSN:
1528-0020
,
0006-4971
DOI:
10.1182/blood-2002-01-0155
Language:
English
Publisher:
American Society of Hematology
Publication Date:
2002
detail.hit.zdb_id:
1468538-3
detail.hit.zdb_id:
80069-7
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