A bone marrow-derived stroma cell line, ST2, can support the differentiation of fetal thymocytes from the CD4+ CD8+ double negative to the CD4+ CD8+ double positive differentiation stage in vitro.
T-cell precursors differentiate into mature T cells predominantly in the thymus. However, it has also been reported that T-cell precursors mature in extrathymic organs such as the liver, bone marrow, or intestines. In order to investigate the nature of the extrathymic microenvironment that supports T-cell maturation, we examined the effect of a bone marrow-derived stroma cell line, ST2, on T-cell precursors by using a reaggregate thymic organ culture (RTOC) system. We found that ST2 cells supported the differentiation of fetal thymocytes at day 14.5 of gestation from a CD4- CD8- double negative (DN) to a CD4+ CD8+ double positive (DP) differentiation stage in a manner similar to that observed in thymus. Anti-interleukin-7 receptor (IL-7R) and anti-c-kit antibodies blocked the growth of thymocytes in RTOC with ST2 cells, but did not inhibit the generation of DP thymocytes. These data indicate that a bone marrow-derived stroma cell, ST2, which supports B-cell differentiation, is also able to support T-cell development and may constitute one of the microenvironmental components for extrathymic T-cell development.
Tong
J
J
Department of Immunology, Faculty of Medicine, Toyama Medical and Pharmaceutical University, Sugitani, Toyama, Japan.
Kishi
H
H
Matsuda
T
T
Muraguchi
A
A
D000818:Animals; D001853:Bone Marrow / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002450:Cell Communication / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002460:Cell Line; D051379:Mice; D008813:Mice, Inbred ICR; D009924:Organ Culture Techniques; D019009:Proto-Oncogene Proteins c-kit / Q000276:immunology; D020395:Receptors, Interleukin-7 / Q000276:immunology; D013950:Thymus Gland / Q000196:embryology / Q000276:immunology*
D020395:Receptors, Interleukin-7; D019009:Proto-Oncogene Proteins c-kit