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Tetranectin is a recently described human plasma protein, which is found in most secretory cells throughout the body, including neutrophils. We present evidence for the presence of tetranectin in human monocytes and macrophages as well, and that these cells upon adherence or weak stimulation release a 20 kDa protein identified as tetranectin by immunoblotting. The amount of tetranectin released is 3-18 ng/h/ 106 monocytes. The possible influence of tetranectin on cellular functions was tested in migration and oxidative metabolism assays. Monocyte spontaneous migration was significantly stimulated by preincubation with purified tetranectin, whereas chemotactic and chemiluminescence responses to fMLP and C5a were unchanged. Neutrophil functions were not affected. It is concluded that tetranectin is secreted from human mononuclear phagocytes upon weak stimulation, and that the secreted tetranectin facilitates spontaneous migration of these cells. [ABSTRACT FROM AUTHOR]

Provided that intracerebral inoculation is applied, an increase in the virus dose from 102 to 104 LD50 of lymphocytic choriomeningitis virus (LCMV) leads to strikingly reduced mortality. To analyse the background for this autointerference, we measured several virologic and immunologic variables in mice infected with these doses of virus. In the high-dose mice we found generally higher organ virus titres and serum interferon titres than in the low-dose mice. Since we could demonstrate that virus-specific T-cell cytotoxicity in spleen, peripheral blood, and meningeal exudate was similar after intracerebral infection with large and small virus doses, and since the LCMV infection in the brain qualitatively and quantitatively was independent of the size of virus inoculum, the explanation for the survival of the high-dose animals is obviously not lack of possibilities for interaction between cytotoxic T cells and infected sensitive targets in the central nervous system. On the other hand, high doses of virus caused a clear suppression of the LCMV-specific delayed-type hypersensitivity (DTH). In addition, when splenocytes from high-dose animals were transferred either intravenously or locally into the footpad of newly virus-challenged mice. DTH was markedly suppressed as compared with the response after transfer of spleen cells from low-dose mice. We therefore conclude that autointerference in the LCMV infection is due to a selectivc suppression of Td function. Large amounts of persistent virus late after infection with high doses of virus suggest a central role for Td function also in virus clearance. Finally, our results indicate the existence of two subsets of K,D region-restricted T cells, one mediating cytotoxicity and the other mediating DTH. This possibility is discussed. [ABSTRACT FROM AUTHOR]

Twenty-two asthmatics received bambuterol solution, a terbutaline pro-drug, once every evening. The following doses were each given orally for 7 days in a double-blind crossover study: 0.185, 0.270 and 0.400 mg/kg. Bambuterol 0.270 mg/kg was preferable regarding clinical effects and side effects. The plasma concentration of generated terbutaline showed a slow linear decrease at all doses. Tests of two methods for objective measurements of tremor in five patients did not add any new data compared with the subjective recordings. [ABSTRACT FROM AUTHOR]

The presence and localization of fibrin and fibronectin in rheumatoid nodules were studied using an indirect immunoperoxidase technique on tissue specimens fixed in formaldehyde, embedded in paraffin and pretreated with pepsin and testicular hyaluronidase. Three zones characteristic for rheumatoid nodules was recognized. 1) Central area with necrosis, containing at least in part fibrinogen-antigenic material and fibronectin especially in the peripheral part of the necrotic area. 2) Around the necrosis a layer of mesenchymal cells in a palisade arrangement was found. Especially in the external part of this layer fibronectin was demonstrated around and between the cells, where fibrin was absent. 3) Peripherally, a zone of non-specific granulation tissue containing moderate amount of fibronectin decreasing towards the surround mature connective tissue, was seen. In the border of the cellular layer vessels were found in variable amount. In some of the vessels vasculitis was demonstrated with the presence of inflammatory cell infiltration, fibrin deposition and occasionally thrombosis. The pathogenesis of the inflammatory reaction in rheumatoid nodules is discussed. [ABSTRACT FROM AUTHOR]

The effect of the opsonic activity of human purified fibronectin on phagocytosis of Staphylococcus aureus by human polymorphonuclear leukocytes was investigated. After opsonization with fibronectin there was a significant increase in the rate of phagocytosis of four out of six Staphylococcus aureus strains. Both attachment to and ingestion by leukocytes was affected, as revealed by lysostaphin treatment. Incubation of leukocytes with fibronectin prior to phagocytosis did not enhance the phagocytosis of Staphylococcus aureus. This shows that the observed enhancement of phagocytosis was dependent on the binding of fibronectin to Staphylococcus aureus. The ability of fibronectin to opsonize different strains of Staphylococcus aureus varied with the strain. A variation was also observed in fibronectin-induced phagocytosis by leukocytes from different donors. [ABSTRACT FROM AUTHOR]