Long-lasting polymorphonuclear leukocyte oxidative burst activation by products of lipopolysaccharide-treated mononuclear cells is only partially due to tumor necrosis factor.

Supernatants of human mononuclear cells cultured in the presence of LPS (LPS-MNC-SN) directly induced production of superoxide by isolated polymorphonuclear leukocytes, measured as superoxide dismutase--inhibitable cytochrome c reduction or, more sensitively, Lucigenin-enhanced chemiluminescence. Of recombinant human cytokines, only TNF and to a lesser degree also LT, but not GM-CSF, showed this activity. Neutralising antibody to TNF reduced the activity of LPS-MNC-SN to activate an oxidative burst in polymorphonuclear leukocytes by 30-50%.

Low-affinity interaction of fibrinogen carboxy-gamma terminus with human monocytes induces an oxidative burst and modulates effector functions.

The interaction of highly purified, monomeric fibrinogen (Fg) with human monocytes (MO) was investigated. In contrast to commercial Fg, no high-affinity binding of monomeric Fg to MO or mononuclear cells could be demonstrated. MO preincubated with Fg in the presence or absence of Ca++ elicited an oxidative burst when triggered with anti-Fg antibodies.

A dual microtiter plate (192 sample) luminometer employing computer-aided single-photon imaging applicable to cellular luminescence and luminescence immunoassay.

In spite of the increasing applications of luminescence measurements, no instrumentation is yet commercially available that permits sensitive luminescence measurements to be performed simultaneously on a large number of samples. Based on the principle of single-photon imaging, we describe here the performance of a computer-aided image luminometer with a capacity for two microtiter plates. Applications to the study of chemiluminescence by a B lymphocyte cell line, and to an IgE luminescence immunoassay are used to exemplify the capabilities of the system, which we have termed 'chemiluminescence multiwell analyser'.

[A rare localization of osteomyelitis in a child].

The authors report a case of osteomyelitis of the anterio-inferior spina iliaca. This original observation actually illustrate the difficulty of the diagnosis of osteomyelitis. They stress the interest of plain radiographs which, if correctly read, would have enabled an early diagnosis, thus avoiding more complex examinations.