Culture and functional studies of mouse macrophages on native-like fibrillar type I collagen.

Freshly isolated, starch-elicited mouse peritoneal macrophages (Mø) attached very efficiently to type I collagen in vitro, if collagen molecules were arranged in ordered supra-molecular assemblies corresponding to the precursor native fibrils. After 6-20h of incubation, the collagen-bound cells were observed to secrete fibronectin, which presumably enhanced cell-collagen interaction associated with cellular differentiation. Mø attachment to collagen could be temporarily inhibited by addition of the linear tri-peptide Arg-Gly-Asp (RGD) to the culture media.

Establishment of permanent cell lines purified from human mesothelioma: morphological aspects, new marker expression and karyotypic analysis.

This study reports the establishment of three major subtypes of human mesothelioma cells in tissue culture, i.e. the epithelioid, sarcomatoid and biphasic forms, and compares their phenotypic and biological characteristics.

Absence of leukocyte microchimerism in oral lichen planus (OLP): an in situ hybridisation study.

Oral lichen planus (OLP) is a relatively common chronic inflammatory disease. The majority of patients are between 30 and 50 years of age with a higher incidence in females. The aetiology is unknown and various hypotheses on the pathogenic mechanisms, including autoimmunity, have been proposed over the years.

Activated human platelets express beta2 integrin.

The expression of molecules of the beta2 integrin family (CD11a, CD11b , CD11c, and CD18) was explored on 2 human megakaryocytic cell lines and on platelets from different donors by immunofluorescence and flow cytometry using a large panel of mAb. CD11a, CD11b, CD11c and CD18 were detected on the megakaryocytic cell lines DAMI and HEL. A low and variable expression of CD11a, CD11b and CD18 determinants was also detected on resting platelets; this expression was markedly increased when platelets were activated by thrombin.

Cytostatic activity of alveolar macrophages from smokers and nonsmokers: role of interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha.

Several functions of alveolar macrophages (AM) are modified by cigarette smoking. AM are the first line of defense in bronchoalveolar spaces and could be depressed in their cytotoxicity to tumor cells in smokers. An assay using A549 cells (human lung adenocarcinoma) as target cells was performed to assess cytostasis mediated by AM and their supernatants (SN) from healthy smokers (n = 8) and nonsmokers (n = 6).

Expression of tumor necrosis factor-alpha and its mRNA in the endometrial mucosa during the menstrual cycle.

Endometrial biopsies, collected at various phases of the menstrual cycle, were examined for the presence of tumor necrosis factor-alpha (TNF-alpha) by histochemistry, and TNF-alpha mRNA by in situ hybridization and Northern blotting. During the proliferative phase, TNF-alpha and TNF-alpha mRNA were not detected or were at low levels. During the secretory phase, the TNF-alpha mRNA level was increased and observed in the wall of coiled arteries.

Protodyne: an immunostimulatory protein component, prepared from gram-positive Bacillus subtilis.

A protein component derived from bacterial protoplasm, called Protodyne, increases the non-specific resistance to infections by bacteria and viruses. Here we show that Protodyne can be prepared not only from Gram-negative bacteria, but also from Gram-positive bacilli. Several preparations of Protodyne, prepared from Bacillus subtilis by phenol extraction or by ammonium sulfate precipitation, were evaluated for immunomodulatory activities in a variety of assays.

Extracellular cytolysis by activated macrophages: studies with macrophages on permeable membranes.

Mouse peritoneal macrophages were allowed to adhere to discs cut from permeable membranes, then activated by incubation in lymphokine-rich supernates from ConA-stimulated spleen cells. Such filter-borne cultures of activated macrophages (AM) were cytotoxic for various target cells (Tc). The kinetics of the cytotoxic process could be monitored by removal of the filter-bound AM after increasing times of contact with Tc.

Membrane particle arrays in SV40-transformed 3T3 cells.

The ultrastructural organization of the plasma membrane of untransformed and simian virus (SV)40-transformed 3T3 cells in culture was studied by an in situ freeze-fracturing technique. Both 3T3 and SV3T3 cells showed randomly distributed intramembrane particles as well as gap junctions. In addition, the plasma membrane (P-face) of confluent SV40-transformed 3T3 cells was found to display a unique membrane specialization which was not observed in normal 3T3 cells.