Phenotypic and functional characterization of c-kit expression during intrathymic T cell development.
We have studied the expression and function of c-kit on subsets of mouse thymocytes. c-kit was primarily expressed on subpopulations of CD4-CD8-CD3- triple negative (TN) cells. The strongest c-kit expression was associated with subsets that represent the least mature TN cells, including CD44+CD25- TN, and a subpopulation of CD25+ TN. These cells were also Thy-1lo, H-2Khi TSA-1hi, HSAlo, B220-, Mac-1-, and Gr-1-. Additionally, the recently described pre-TN thymocyte population (CD4loCD3-CD8-) was also c-kit+. CD25+ TN thymocytes proliferated in the presence of IL-7 and stem cell factor (the ligand for c-kit), and this proliferation was completely inhibited in the presence of anti-c-kit. Furthermore, the addition of anti-c-kit to 2-deoxyguanosine-treated fetal thymic lobes undergoing reconstitution with fetal liver-derived precursor cells inhibited their T cell differentiation potential. These observations indicate an important role for c-kit/stem cell factor interactions during early thymocyte development.
Godfrey
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DI
DNAX Research Institute, Palo Alto, CA 94304.
Zlotnik
A
A
Suda
T
T
D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D005260:Female; D016298:Hematopoietic Cell Growth Factors / Q000494:pharmacology; D015851:Interleukin-7 / Q000494:pharmacology; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011247:Pregnancy; D011505:Protein-Tyrosine Kinases / Q000032:analysis*; D011518:Proto-Oncogene Proteins / Q000032:analysis* / Q000502:physiology; D019009:Proto-Oncogene Proteins c-kit; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D015375:Receptors, Interleukin-2 / Q000032:analysis; D019089:Stem Cell Factor; D013601:T-Lymphocytes / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology*
D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D016298:Hematopoietic Cell Growth Factors; D015851:Interleukin-7; D011518:Proto-Oncogene Proteins; D011948:Receptors, Antigen, T-Cell; D015375:Receptors, Interleukin-2; D019089:Stem Cell Factor; D011505:Protein-Tyrosine Kinases; D019009:Proto-Oncogene Proteins c-kit