Human peripheral blood monocytes (HPBM) isolated from normal donors by centrifugal elutriation were divided into two populations according to volume. (Median volumes of small monocytes (SM) and large monocytes (LM) were 255 μm3 and 280 μm3, respectively). H2O2 production was determined during in vitro culture and in response to bacterial lipopolysaccharide (LPS), and to recombinant human interferon-γ (rIFN-γ). On day 1, H2O2 production by LM was significantly greater than that by SM. In vitro culture of SM resulted in an augmented ability to produce H2O2. By day 3, SM were the major H2O2 producers. Freshly isolated SM and LM, exposed for 24 hr to LPS and rIFN-γ, showed different patterns of activation. Both SM and LM responded to LPS, with LM responding maximally at lower doses than SM. Only SM showed a significant augmentation of H2O2 production with rIFN-γ treatment. We also assessed the effect of in vitro culture with activation. SM but not LM showed an increased H2O2 to LPS and rIFN-γ after 7 days in culture. Continuous exposure of SM to rIFN-γ resulted in maximal H2O2 production at day 3 of culture; this pattern was not seen for LPS. The production of H2O2 by HPBM is related to in vitro maturation. The enhanced H2O2 production by HPBM upon exposure to rIFN-γ may be related to the induction of in vitro maturation.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Immunology|
|State||Published - 1986|
ASJC Scopus subject areas
- Immunology and Allergy