The murine myeloid cell line 32Dcl3 as a model system for studying neutrophil functions (1)
The murine myeloblastic cell line 32DCl3 is an interleukin-3 (IL-3)-dependent cell line, which has been used to study signaling for myeloid proliferation and differentiation. Replacement of IL-3 with rhG-CSF triggers an initial proliferation for 4 – 5 days followed by growth arrest and apparent neutrophil-like morphology by 12 days.
The cell morphology was changed in response to G-CSF during day 0 to 12. The shape and diameter of murine neutrophils and the differentiated 32Dcl3C were similar.
Mature 32Dcl3C cells were more efficient in phagocytosis than murine neutrophils, and they exhibited a greater response to PMA stimulation.
Differentiated 32Dcl3C cells killed bacteria in a time-dependent manner similar to murine neutrophils.
The combined effects of cytocalasin B + fMLP or cytocalasin B + PMA significantly increased MPO secretion from murine neutrophils as well as 32Dcl3C.
Murine neutrophils express relatively higher levels of Mac-1 but differentiated 32Dcl3C cells express more LFA-1. CD18 expression level is similar for both cell types.
Differentiated 32Dcl3C cells and murine neutrophils efficiently adhered to L-cells expressing ICAM-1, and the adhesion could be partially blocked by pre-incubating cells with anti-mouse LFA-1 antibody. fMLP promoted significant adhesion of differentiated 32Dcl3C cells and murine neutrophils to KLH, though murine neutrophil adhesion was signif- icantly higher than 32Dcl3C cells.
Neither immature nor differentiated 32Dcl3C cells released superoxide in response PMA, whereas murine neutrophil increased superoxide release in response to PMA.
