Interleukin 3 mediates interleukin 6 production in murine interleukin 3-dependent hemopoietic cells.
A series of murine interleukin 3 (IL-3)-dependent hemopoietic cell lines was studied for the capacity to produce interleukin 6 (IL-6) in vitro. These included a bone marrow-derived mast cell line (L138.8A) and several early myeloid cell lines described in the literature (DA-1, DA-3, NFS-60, NFS-78, FDC-P1, FDC-P2, FDC-PmixA4, and 32Dcl.23). All of these cell lines produced growth factor activity for IL-6-dependent hybridoma cells (7TD1), which was completely neutralized by the monoclonal anti-IL-6-antibody 6B4. IL-6 expression was also evident at the mRNA level using a murine IL-6-specific cDNA probe. In 32Dcl.23 cells (2 x 10(5)/ml) stimulated for 24 hr with serial dilutions of purified murine IL-3, a positive correlation was found between the IL-3 dose and the amount of IL-6 measured in the conditioned media. At 24 hr this correlation was not evident at the mRNA level. However, prolonged exposure of 32Dcl.23 cells (up to 72 hr) to either a high (60 U/ml) or a low IL-3 concentration (1 U/ml) revealed a time-dependent increase and decrease, respectively, of IL-6 mRNA levels. At both IL-3 concentrations 32Dcl.23 cells remained in a fully viable and proliferative state. The influence of IL-3 on IL-6 release could be specifically counteracted by anti-IL-3-antiserum. IL-6 added alone or in concert with IL-3 did not stimulate 32Dcl.23 proliferation.(ABSTRACT TRUNCATED AT 250 WORDS)
Hültner
L
L
GSF-Institut für Experimentelle Hämatologie, Munich, Federal Republic of Germany.
Szöts
H
H
Van Snick
J
J
Moeller
J
J
Welle
M
M
Dörmer
P
P
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D006413:Hematopoietic System / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007377:Interleukin-3 / Q000494:pharmacology*; D015850:Interleukin-6 / Q000096:biosynthesis*; D007700:Kinetics; D051379:Mice; D012333:RNA, Messenger / Q000378:metabolism
D007377:Interleukin-3; D015850:Interleukin-6; D012333:RNA, Messenger