title: Synergistic effect of IL-4 and TNF-alpha in the induction of monocytic differentiation of a mouse myeloid leukaemic cell line (WEHI-3B JCS).
abstract: We have previously shown that non-cytotoxic concentrations (600-1200 U/ml) of recombinant mouse tumour necrosis factor-alpha (TNF-alpha) can induce differentiation of a subclone (JCS) of the WEHI-3B myelomonocytic leukaemia cell line into mature cells with the characteristics of macrophages. In the present study, the effects of recombinant mouse interleukin-4 (IL-4), either alone or in combination with mouse TNF-alpha, on the growth and differentiation of JCS cells were examined. IL-4 alone (20-5000 U/ml) inhibited the growth of JCS cells in a dose-dependent manner but did not induce cell differentiation. However, combinations of IL-4 and TNF-alpha acted in synergy to inhibit cell proliferation and induce monocytic differentiation of JCS cells, as shown by increased expression of the macrophage differentiation antigens (F4/80, Mac-1), stimulation of phagocytic activity, induction of non-specific esterase and NBT-reducing activities, increased plastic adherence and morphological criteria. Similar synergistic interactions were also shown by human TNF-alpha and mouse IL-4, indicating that TNF-alpha might exert its effects through the low-affinity (p55) TNF receptors. Moreover, the clonogenicity of JCS cells in vitro and their tumorigenicity in vivo were significantly reduced by combined TNF-alpha and IL-4 treatment. Our results indicate that TNF-alpha can act as a differential signal for JCS cells and that its effects are modulated by IL-4. Therefore, the combination of TNF-alpha and IL-4 may be useful in the treatment of some forms of myelomonocytic leukaemia.
authors.affiliation: Experimental Haematology Group, John Curtin School of Medical Research, Australian National University, Canberra.
authors.forename: K N
authors.initials: KN
authors.lastname: Leung
authors.forename: N K
authors.initials: NK
authors.lastname: Mak
authors.forename: M C
authors.initials: MC
authors.lastname: Fung
authors.forename: A J
authors.initials: AJ
authors.lastname: Hapel
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005260:Female; D015847:Interleukin-4 / Q000494:pharmacology*; D007951:Leukemia, Myeloid / Q000276:immunology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000166:cytology*; D014411:Neoplastic Stem Cells / Q000187:drug effects; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4