K. Sankaran et Hb. Herscowitz, PHENOTYPIC AND FUNCTIONAL-HETEROGENEITY OF THE MURINE ALVEOLAR MACROPHAGE-DERIVED CELL-LINE MH-S, Journal of leukocyte biology, 57(4), 1995, pp. 562-568
We have previously reported that MH-S, an established murine alveolar
macrophage-derived cell line, mediated profound inhibition of in vitro
antibody production, as did their freshly isolated alveolar macrophag
e (AM) counterparts, In this communication we show that like freshly r
ecovered AMs, the MH-S cell line also displays phenotypic and function
al heterogeneity, Sorting of parental MH-S cells by flow cytometry bas
ed on reactivity with anti-Mac-1 antibody yielded two subsets. Further
analysis by staining with monoclonal antibodies against well-characte
rized murine macrophage cell surface markers revealed that both Mac-1(
+) and Mac-1(-) subsets expressed the mature murine macrophage antigen
(F4/80) and class II major histocompatibility complex molecules, but
with different intensity. In contrast, the two subsets stained equival
ently with antibody against the Fc gamma II receptor, whereas neither
subset stained with anti-CD4 antibody, Examination by light microscopy
revealed pleomorphism in the Mac-1(+) population with many of the cel
ls appearing spindle shaped and having elongated processes, whereas a
majority of the cells in the Mac-(1)- population were spherical in sha
pe. Functionally, cells from the Mac-1(+) population were less inhibit
ory of in vitro antibody production and produced significantly more ni
tric oxide in response to stimulation with lipopolysaccharide than wer
e cells in the Mac-1(-) population. Essentially similar results were o
btained using cloned Mac-1(+) and Mac-1(-) MH-S cells, The finding of
heterogeneity in an established cell line that displays functions simi
lar to those of freshly recovered AMs suggests that distinct subsets o
f AMs may be involved in the pathogenesis of disease processes in the
lung.