Stem Cells
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Reprints/Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Benedetti, F.
Right arrow Articles by Perona, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Benedetti, F.
Right arrow Articles by Perona, G.

Stem Cells, Vol 12, 205-213, Copyright © 1994 by AlphaMed Press

ORIGINAL ARTICLES

T suppressor activated lymphocytes (CD8+/DR+) inhibit megakaryocyte progenitor cell differentiation in a case of acquired amegakaryocytic thrombocytopenic purpura

F Benedetti, D de Sabata and G Perona
Department of Hematology, Verona University School of Medicine, Italy.

Acquired amegakaryocytic thrombocytopenic purpura (AATP) is a rare disease, characterized by isolated thrombocytopenia and the absence of megakaryocytes in bone marrow. Recent studies suggest that this syndrome is due to diverse etiologies. Humoral or cellular mediated suppression has been alternately demonstrated using an in vitro colony assay for megakaryocytic progenitor cells (colony forming units megakaryocyte, [CFU-meg]). We studied a patient affected by AATP, who was not responsive to conventional therapy, but did respond to antilymphocyte globulin. The immunological characterization of marrow lymphocytes showed a marked increase of T activated suppressor cells (CD8+/DR+). Low density bone marrow mononuclear nonadherent cells (MNAC) from the patient, either in aplastic phase or in remission phase, were plated in plasma clot either directly or after T cell depletion (T-dep MNACs). Co-cultures with normal marrow cells were performed using either T lymphocytes from a normal volunteer donor or patient T lymphocytes. In some experiments we added autologous serum instead of fetal calf serum (FCS). In standard conditions, we observed increased colony formation, which was more evident in remission phase and especially significant after T cell depletion. The T lymphocytes from patient marrow did not modify the number of CFU-meg when co- cultured with allogeneic cells. These results indicate that an immune- mediated mechanism could be responsible for this case of AATP, and that the T cell subset CD8+/DR+ is capable of exerting suppression on megakaryocyte differentiation. This suppressive effect seems restricted to patient cells, suggesting a specific auto-sensitization.


This article has been cited by other articles:


Home page
 JCOHome page
W. H. Witteles, S. L. Schrier, and H. A. Wakelee
Lung Cancer Presenting With Amegakaryocytic Thrombocytopenia
J. Clin. Oncol., March 1, 2008; 26(7): 1171 - 1174.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
STEM CELLS THE ONCOLOGIST CME ALPHAMED PRESS JOURNALS

Copyright © 1994 by AlphaMed Press.