Effects of increasing IL-7 availability on lymphocytes during and after lymphopenia-induced proliferation.
IL-7 is critically involved in regulating peripheral T cell homeostasis. To investigate the role of IL-7 on lymphopenia-induced proliferation of polyclonal lymphocytes, we have transferred CFSE-labeled cells into a novel T-lymphopenic, IL-7-transgenic mouse line. Results obtained indicate that T and B cells do not respond in the same way to IL-7-homeostatic signals. Overexpression of IL-7 enhances proliferation of both CD4(+) and CD8(+) T cells but with distinctly temporal effects. Expansion of naturally arising CD4(+)-regulatory T cells was like that of conventional CD4(+) T cells. IL-7 had no effect on B cell proliferation. By immunohistology, transferred T cells homed to T cell areas of spleen lymphoid follicles. Increasing IL-7 availability enhanced T cell recovery by promoting cell proliferation and reducing apoptosis during early stages of lymphopenia-induced proliferation. Taken together, these results provide new insights into the pleiotropic effects of IL-7 on lymphopenia-induced T cell proliferation.
Institut National de la Santé et de la Recherche Médicale Unité 548, Département de Réponse et Dynamique Cellulaire, Commissariat à l'Energie Atomique-G, Grenoble, France.
Nabil
N
Bosco
Fabien
F
Agenès
Rhodri
R
Ceredig
D019264:Adoptive Transfer; D000818:Animals; D017209:Apoptosis; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology; D017252:CD3 Complex / Q000235:genetics / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D049109:Cell Proliferation; D005260:Female; D015870:Gene Expression; D006706:Homeostasis; D015851:Interleukin-7 / Q000235:genetics / Q000378:metabolism*; D008214:Lymphocytes / Q000276:immunology* / Q000473:pathology*; D008231:Lymphopenia / Q000276:immunology* / Q000473:pathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic
D017252:CD3 Complex; C485468:Cd3e protein, mouse; D015851:Interleukin-7