Presence of a very small population of Thy-1+, L3T4+ cells producing large amounts of IL-3 in young athymic nude mice.
A mixture of phorbol myristate acetate (PMA) and ionomycin was found to stimulate spleen and lymph node cells (LNC) from 6 to 8 week-old-athymic BALB/c nude mice, as well as from control +/+ mice, to secrete interleukin-3 (IL-3) in vitro. The specificity of the IL-3 bioassay was attested to by the use of rabbit anti-IL-3 antibodies, and by the detection of an accumulation of IL-3 mRNA. Cytotoxic treatment with relevant antibodies showed that the cells responsible for the IL-3 production in athymic nude mice was Thy-1+, L3T4+, Ly2-, while both L3T4+ and Ly 2+ cells produced IL-3 in control +/+ mice. Although the levels of IL-3 secreted by nude LNC varied among experiments, nude LNC were able to produce IL-3 at a level comparable to or higher than +/+ LNC. In addition, nude LNC consistently secreted two to three times more granulocyte-macrophage colony-stimulating factor (GM-CSF) than +/+ LNC, and the majority of GM-CSF secretion was dependent on the presence of L3T4+ cells. In contrast, IL-2 production by nude LNC was markedly limited. Since the flow microfluorometry analysis failed to demonstrate the presence of L3T4+ cells (less than 1%) in nude LNC, compared with 40-50% L3T4+ cells in +/+ LNC, our results suggest that athymic nude mice have a small population of Thy-1+, L3T4+ cells characterized by its ability to secrete IL-3 and GM-CSF at a very high rate.
Kimoto
M
M
Department of Pathology, University of Geneva, Switzerland.
de Kossodo
S
S
Kindler
V
V
Detraz
M
M
Vassalli
P
P
Izui
S
S
D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D000954:Antigens, Surface / Q000032:analysis*; D002478:Cells, Cultured; D007377:Interleukin-3 / Q000378:metabolism*; D015759:Ionomycin; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D013755:Tetradecanoylphorbol Acetate; D018800:Thy-1 Antigens
D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D007377:Interleukin-3; D018800:Thy-1 Antigens; D015759:Ionomycin; D013755:Tetradecanoylphorbol Acetate