Influence of T lymphocytes on hematopoiesis in a patient with T cell hypoplasia.
In this communication, we describe an unusual patient with a reported lifelong history of anemia. Investigation of the pathogenesis of this patient's bone marrow failure provided an interesting opportunity to determine the role of T cells in the regulation of human blood cell production. Phenotyping of the patient's mononuclear cells revealed severe T cell hypoplasia in both the peripheral blood and bone marrow. The patient's bone marrow was capable of producing 50-60% of the normal numbers of burst-forming units--erythroid (BFU-E) in the presence of optimal concentrations of erythropoietin, suggesting that marrow BFU-E formation is in part independent of T cells. Addition of small numbers of class I identical donor T cells enhanced BFU-E cloning efficiency to a level observed in normal controls. This enhancing effect was supplied by a T4+ (CD4) population of donor cells. The addition of donor T cells partially corrected the inability of patient marrow cells to produce megakaryocyte and mixed colonies. These studies suggest that prolonged T cell hypoplasia might deprive marrow progenitor and stem cells of a necessary enhancing effect that is required for sustained normal hematopoiesis. Such a T cell defect in rare instances may result in bone marrow failure.
Hoffman
R
R
Hematology/Oncology Section, Indiana University School of Medicine, Indianapolis 46223.
Lu
L
L
Jansen
J
J
Bruno
E
E
Brandt
J
J
Boral
L
L
Cheung
K
K
D000368:Aged; D000740:Anemia / Q000097:blood* / Q000473:pathology; D001853:Bone Marrow / Q000473:pathology; D003114:Colony-Forming Units Assay; D004920:Erythropoiesis; D005260:Female; D006098:Granulocytes / Q000473:pathology; D006410:Hematopoiesis; D006801:Humans; D008264:Macrophages / Q000473:pathology; D008533:Megakaryocytes / Q000473:pathology; D010641:Phenotype; D013601:T-Lymphocytes / Q000145:classification / Q000473:pathology / Q000502:physiology*