Effect of LPS on the oxidative metabolism of peritoneal and spleen cells from LPS sensitive and resistant mice.

The influence of LPS on peritoneal and spleen cell oxidative metabolism was investigated in LPS sensitive (C57BL/6) and LPS resistant (C3H/HeJ) mice following intraperitoneal or subcutaneous injection, by measurement of chemiluminescent (CL) responses to latex particles. In C57BL/6 mice, LPS induced a marked increase in peritoneal and spleen cell CL responses, regardless of the route of injection. On the 2nd day, the effect of LPS on peritoneal cells could be fully explained by an inflammatory reaction, while on the 4th day it could be related to an "activated state" of peritoneal macrophages. In contrast, such an in vivo effect of LPS in peritoneal or spleen cell CL responses was not found in C3H/HeJ mice except on the 2nd day following the injection and with the highest LPS dosage and could be totally due to the LPS induced inflammatory reaction. In vitro studies showed that extremely low concentration of LPS increased CL response capacities of C57BL/6 spleen cell to latex particles. In contrast, CL responses from C3H/HeJ spleen cells remained unaffected by LPS except when submitted to concentrations which proved toxic for the sensitive strain CL producing cells. These results lend additional evidence for the involvement of reactive oxygen species (ROS) in the metabolic consequences of LPS-induced macrophage activation.

Acute effects of orally administered levamisole on random monocyte motility and chemotaxis in man.

Cellular immune functions were studied in patients with early bladder cancer 2 hours after ingestion of either levamisole or a placebo. Random monocyte motility was significantly increased (P less than 0.025) in 13 of 17 patients receiving levamisole. Monocyte chemotaxis was significantly increased (P less than 0.025) in 16 of the 17 patients. Random monocyte motility and monocyte chemotaxis did not change in either 8 patients on the placebo or in 15 normal controls. Monocytes from normal donors showed increased random motility and chemotaxis after incubation with levamisole in vitro. These results indicated that increases in peripheral blood monocyte motility followed oral administration of levamisole. Kinetic studies indicated that these effects were rapid in onset and short lived.

Serological characterization of human monocytes for HLA, B-lymphocyte, granulocyte, and monocyte-associated antigens by cytotoxicity testing.

Highly enriched preparations of monocytes, B and T lymphocytes, and granulocytes from 18 normal donors were serotyped in parallel in a complement-dependent cytotoxicity assay using allogeneic and heterologous antisera defining three independent tissue antigen systems. HLA and B-lymphocyte tissue antigens were detected on human monocytes although granulocyte antigens were absent. By cytotoxicity testing the presence of Ia-like antigens on monocytes was significantly diminished compared to the autologous B-lymphocyte population and has important implications in B-lymphocyte serology. The study indentified a number of human antisera obtained from multitransfused subjects and pre- and post-transplant organ recipients that were non-HLA and appeared to define monocyte-associated antigens. The serological implications of surface antigen expression on human monocytes compared with other peripheral blood cells are discussed.

Two-step separation of human peripheral blood monocytes on discontinuous density gradients of colloidal silica-polyvinylpyrrolidinone.

Normal human peripheral blood monocytes were purified by a two-step separation. The first step, the standard Ficoll--Hypaque (F--H) buoyant density centrifugation, yielded mainly mononuclear cells, of which 24 +/- 9% were monocytes. Isopycnic centrifugation on discontinuous gradients of colloidal silica polyvinylpyrrolidinone (CS-PVP) further separated these mononuclear cells. The density interface between 1.070 and 1.060 g/ml yielded 82 +/- 7% monocytes, 5 +/- 4% granulocytes and 13 +/- 8% lymphocytes. Sixty-six percent of the monocytes obtained after F--H separation were recovered in this layer. The monocytes were intact and viable and retained their ability to phagocytose and kill Candida pseudotropicalis and to spread on glass coverslips. Motility (both random and towards a chemoattractant) was retained but was quantitatively less than after F--H separation alone. The relative purity of the monocyte population allowed assessment of major histocompatibility surface antigens by serotyping. This confirmed the presence of HLA and Ia-like antigens on monocytes.