Open AccessIntrathymically Injected Hemopoietic Stem Cells Can Differentiate into All Lineage Cells in the Thymus: Differences Between c‐kit + Cells and c‐kit <low Cells
Author(s) -
Lian Zhexiong,
Toki Junko,
Yu Chengze,
Hayashi Haruki,
Yasumizu Ryoji,
Sugiura Kikuya,
Jin Tienan,
Inaba Muneo,
Hisha Hiroko,
Li Yongan,
Yu Wanlong,
Fan Hongxue,
Ikehara Susumu
Publication year - 1997
Publication title -
stem cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.159
H-Index - 229
eISSN - 1549-4918
pISSN - 1066-5099
DOI - 10.1002/stem.150430
Subject(s) - biology , haematopoiesis , stem cell , microbiology and biotechnology , precursor cell , immunology , cell , genetics
Abstract To investigate whether hemopoietic stem cells (HSCs) can differentiate into all lineage cells even in the thymus, we injected two types of HSCs (c‐kit + and c‐kit <low cells) obtained from C57BL/6 Ly5.1 mice directly into the thymus of 7.5 Gy‐irradiated C57BL/6 Ly5.2 mice. When c‐kit <low cells (low density/lineage − /CD71 − /major histocompatibility complex class I high /Sca‐1 + /Thy‐1 low / c‐kit <low ) were injected, donor‐derived (Ly5.1) cells were detected on day 8 after intrathymic (i.t.) injection, and the number reached a maximum on day 24 after injection. Granulocytes and macrophages were also detected on day 8 after injection. However, B220 + B cells were observed on day 13. Eighteen days after i.t. injection, the injected lobes showed red color due to the synchronous development of erythroid cells. Histological studies revealed the development not only of erythroid lineage cells but also of megakaryocytes in the thymus. In contrast, when c‐kit + cells were injected, a significant number of donor‐derived cells were detected on day 5 after i.t. injection (three days earlier than in the case of c‐kit <low cell injection). The differentiation into erythroid lineage cells was also observed six days earlier than when c‐kit <low HSCs were injected. These findings suggest that c‐kit <low HSCs are more primitive than c‐kit + HSCs, although both can differentiate into all lineage cells after i.t. injection.