Generation of macrophages from early T progenitors in vitro.
Early T progenitors in the thymus have been reported to have the capacity to develop into B cells, thymic dendritic cells, and NK cells. Here we describe conditions that induce early T progenitors to develop into macrophages. Initially, we observed that early T progenitors could be induced to develop into macrophages by cytokines produced from a thymic stromal cell line, TFGD, and later we found that the cytokine mixture of M-CSF plus IL-6 plus IL-7 also induced macrophage differentiation from pro-T cells. M-CSF by itself was unable to induce macrophage differentiation from early T progenitors. To correlate this observation with the developmental potential of early T progenitors, mouse embryonic thymocytes were sorted into four populations, pro-T1 to pro-T4, based on the expression of CD44 and CD25, and then cultured with TFGD culture supernatant. We found that pro-T1 and pro-T2 cells, but not pro-T3 and pro-T4 cells, generate macrophages. Limiting dilution analysis of the differentiation capability of sorted pro-T2 cells also confirmed that pro-T2 cells could generate macrophages. These results suggest that T cells and thymic macrophages could originate from a common intrathymic precursor.
Lee
C K
CK
College of Pharmacy, Chungbuk National University, Cheongju, South Korea. cklee@cbucc.chungbuk.ac.kr
Kim
J K
JK
Kim
Y
Y
Lee
M K
MK
Kim
K
K
Kang
J K
JK
Hofmeister
R
R
Durum
S K
SK
Han
S S
SS
D000818:Animals; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002469:Cell Separation; D002474:Cell-Free System / Q000276:immunology; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004338:Drug Combinations; D005333:Fetus; D016130:Immunophenotyping; D015850:Interleukin-6 / Q000502:physiology; D015851:Interleukin-7 / Q000502:physiology; D016173:Macrophage Colony-Stimulating Factor / Q000502:physiology; D008264:Macrophages / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D013234:Stem Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D014407:Tumor Cells, Cultured
D017077:Culture Media, Conditioned; D004338:Drug Combinations; D015850:Interleukin-6; D015851:Interleukin-7; D016173:Macrophage Colony-Stimulating Factor