Screening of effects of selenomethionine-enriched yeast supplementation on various immunological and chemical parameters of skin and blood in psoriatic patients.

Selenium (Se) is known to affect the immune system, and decreased Se-levels in blood of patients with moderate or severe psoriasis have been reported. In this study, the effect of Se-supplementation (400 micrograms/day for 6 weeks as Se-yeast, containing about 70% selenomethionine, SeMet) on skin and blood Se-content, on skin glutathione peroxidase activity and on various chemical and immunological parameters of blood and skin was investigated in 7 psoriatic patients. Before the SeMet-supplementation, serum and blood Se-levels were at the normal range, but they increased 42-45% during the Se-dosage, while zinc levels remained unchanged. Se-dependent glutathione peroxidase activity in both normal and lesional psoriatic skin remained unchanged during the trial, although a small net Se-uptake was detected. At the same time, a slight but statistically significant increase in the number of CD4+ T-cells was observed in the reticular dermis of the psoriatic lesions whereas the numbers of CD8+, CD11c+, and CD1+ cells were not significantly altered. Also, a relatively high number of patients (3 out of 7) showed a strongly reduced number of gamma/delta T-lymphocytes or increased CD8+ T-cells (2 patients) in peripheral blood. However, SeMet-supplementation was not related to these abnormalities or to the number of other peripheral blood immunocytes or to serum immunoglobulin levels. In addition, no marked effect on the clinical condition of the patients was observed. This pilot study suggests that SeMet may be able to modulate the immunological mechanism of psoriatic lesions by increasing the number of CD4+ T-cells.

Nasal sensitization of dairy farmers to bovine epithelial and urinary antigens.

Nineteen dairy farmers with nasal symptoms associated with working in cowhouses participated in the study. Nasal challenge with bovine epithelial antigen (BEA) and bovine urinary antigen (BUA) was made before and after the indoor feeding season. Nasal challenge made before the indoor feeding season with BEA was positive in five patients and three of them showed positive reaction in nasal challenge also with BUA. After the indoor feeding season the results in nasal challenge with BEA were approximately equal to BEA and four of them showed positive response in nasal challenge to BUA. However, we did not find any significant increase in sensitivity in nasal challenge to BEA or BUA after the indoor feeding season. In addition to these patients, two patients who were excluded from nasal challenge before the indoor feeding season showed positive results in nasal challenge after the indoor feeding season with both BEA and BUA. Our results suggest that BUA in addition to BEA may have significance to nasal symptoms.

T-lymphocyte subsets defined by double immunofluorescence in multiple sclerosis.

T-lymphocyte subpopulations were studied in the blood of 25 multiple sclerosis patients and 25 healthy age and sex-matched controls. Monoclonal antibodies labelled with different fluorochromes were used to define the percentages of CD4 (helper/inducer) and CD8 (suppressor/cytotoxic) positive cells and to dissect them into phenotypic subgroups. The results confirm the decrease in CD8 positive cells in the blood associated with multiple sclerosis. The subset showing the most marked decrease was the CD11 marker negative population, which has been reported to be associated with cytotoxicity rather than suppression. There was no significant decrease in the percentage of cells positive for both CD4 and CD45R markers reported to contain suppressor-inducer or naive T-helper cells in the MS patients. The results suggest that further dissection of T-cell subpopulations may clarify our understanding of this disease process.

Tumorigenicity and H-2 expression of papillomavirus-transformed mouse cell lines.

Tumorigenicity in immunocompetent syngeneic mice and H-2 class I antigen expression of BPV1-transformed mouse cell lines had no correlation. H-2 expression was examined using monoclonal anti-(H-2Kb) and anti-(H-2Db) antibodies in immunofluorescence staining for flow cytometry analysis and by determining the sensitivity of the cells to cytolysis by allostimulated spleen cells. Nontumorigenic cell lines were as resistant as tumorigenic cell lines to natural killer activity. The results indicate that in our model defence by natural killer cells is not a decisive factor. The results also show that instead of or in addition to H-2 class I antigens other factors (e.g. the presence or absence of virus-specific antigens) are important in determining the tumorigenicity of BPV1-transformed cell lines.

Lymphocyte subsets in the cerebrospinal fluid in active multiple sclerosis.

We studied the relative number of lymphocyte subsets in the cerebrospinal fluid (CSF) of patients with active multiple sclerosis. The cells were double-labeled with monoclonal antibodies and were studied using a fluorescence-activated cell analyzer. The number of Leu2+Leu15+ cells and Leu3+Leu18+ cells was markedly reduced in the CSF but not in the peripheral blood of the patients. The number of Leu3+Leu18+ cells was reduced also in the CSF of control patients (patients with other inflammatory or infectious neurological diseases).

Comparative immunochemical analysis of five Thermoactinomyces strains.

The antigen structures in mycelial extracts of 4 strains of Thermoactinomyces vulgaris and 1 strain of Thermoactinomyces candidus were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining. For immunological characterization, antigens were transferred electrophoretically to nitrocellulose membranes and blotted with T. vulgaris strain-specific antisera and with sera of farmer's lung patients. Cross-reactions between the strains were also studied using immunodiffusion and crossed immunoelectrophoresis. Protein components between 50 and 60 kilodaltons were found to be the most immunogenic. Patient sera showed heterogeneous responses, but all reacted with an antigen at 55 kilodaltons that was also common to all strains studied.

Lymphocyte activation with release of soluble mediators induced by Thermoactinomyces vulgaris in vitro.

Murine spleen lymphocytes stimulated in vitro with a hypersensitivity pneumonitis-associated bacterium, Thermoactinomyces vulgaris, were found to secrete interleukin-2 up to 7 days after mitomycin C blockade. They exerted helper effect in secondary mitogen or antigen-induced lymphocyte proliferation. Cyclosporin A, an inhibitor of interleukin-2 synthesis, caused a complete abrogation of the helper effect, suggesting that the effect was mainly due to interleukin-2. Indomethacin, an inhibitor of prostaglandin synthesis, enhanced the helper effect in some inbred strains of mice, indicating prostaglandin-dependent downregulation. The strain variation in the prostaglandin-induced downregulation was not H-2 linked.

Immunomodulating properties of lymphocytes activated by farmer's lung associated bacterium Thermoactinomyces vulgaris in vitro.

Thermoactinomyces vulgaris, one of the aetiological agents of farmer's lung, was analysed for its ability to activate non-immune spleen lymphocytes from 10- to 14- week-old mice. The lymphocytes were found to exert both enhancing and suppressing signals after activation, depending on the secondary stimulation used. The enhancing effect is due to interleukin-2 secreted mainly by L3T4+ lymphocytes. The suppressive action is associated with Lyt2+ lymphocytes, which are probably activated by prostaglandins or histamine; but the suppression inducer action of L3T4+ lymphocytes may also be important. Genetic regulation, independent of H-2K and D, was also detected between different inbred strains of mice in response to T. vulgaris. The genetic regulation appeared associated with the different responsiveness of Lyt-2 positive lymphocytes between different strains. These results emphasize the importance of nonspecific activation in hypersensitivity disorders induced by microbiol antigens.

Tumour-associated antigens in primary mouse fibroblasts induced by transformation with bovine papillomavirus type 1.

Bovine papillomavirus type 1 (BPV 1) DNA was used to transform primary fibroblasts of C57BL/6J mice. Transformation frequency in these cells was much lower than in C127 cells and not associated with the appearance of morphologically distinct foci. However, continuous lines of transformed C57BL/6J cells were developed by serial subculturing of transfected cells. These transformed cell lines showed phenotypic properties associated with transformation including abnormal karyotypes. They contained variable amounts of viral DNA, but the copy number was in the same range as in six C127 transformants tested for comparison. In two cell lines monomeric viral DNA in an episomal form was detected. Slowly migrating viral sequences in these and in the third line were probably episomal concatamers, but the possibility of integration could not be excluded. There was some variation in immunogenicity, but all cell lines induced a cell-mediated immune response in syngeneic mice detected by the chromium release assay. In addition to BPV 1-transformed cell lines, the effector cells also reacted against an unidentified antigen shared by 2 cell lines transformed by SV40 and UV irradiation, respectively.

Interactions of Thermoactinomyces vulgaris and mouse alveolar macrophages. Loss of mitogenic activity and release of suppressive prostaglandins and interleukin 1.

Interactions of mouse alveolar macrophages from three different inbred strains of mice and Thermoactinomyces vulgaris, a microbe associated with Farmer's lung disease, were studied. Alveolar macrophages were found to abolish the mitogenic activity of T. vulgaris. A prostaglandin synthesis inhibitor indomethacin, could not restore the activity. Alveolar macrophage supernatants generated by T. vulgaris treatment exerted strong suppression in secondary concanavalin A-induced lymphocyte transformation. Indomethacin partly relieved the suppression but a histamine 2 receptor blocker, cimetidine, had no effect. Interleukin 1 activity was practically undetectable by the thymocyte co-stimulation assay unless indomethacin was used. When indomethacin was used, interleukin 1 activity could be detected in all strains of mice tested. Major differences in the abolition of the mitogenic effect, in the suppressive effect, or in the release of interleukin 1 were not detected between inbred strains of mice tested. The results indicate that alveolar macrophages exert suppressive actions in vitro after T. vulgaris treatment but in vivo activities remain to be elucidated.

Pulmonary and immune responses to a Thermoactinomyces vulgaris antigen respiratory sensitization in C57BL/6J mice.

Lung histology and immune responses were followed during a six month period of Thermoactinomyces vulgaris antigen respiratory sensitization of C57BL/6J mice. Histologically, the mice developed a picture resembling the subacute stage of human farmer's lung. At the early phase of the sensitization a T-cell response was seen in vitro, characterized by an increased spleen but no peripheral blood lymphocyte reactivity to T-cell mitogens at the same time as increased reactivity to the sensitizing antigen was detected. An increase in the percentage of T-cells in the lavage cell population was also seen. The sensitization was associated with the appearance of both IgG and IgA antibodies in lavage and in serum of which lavage IgA antibodies were found to follow the course of the sensitization most accurately. The increase in antibody titers was not, however, reflected in lavage cytology or in lymphocyte reactivity. The results suggest that different immunological reactions may be predominant at different stages of farmer's lung.

Experimental allergic alveolitis in mice induced by Thermoactinomyces vulgaris.

A model of allergic alveolitis was developed in inbred mice. Antigen suspension prepared from Thermoactinomyces vulgaris was applicated intranasally in C3H/He mice. Lung histology, serum IgG and IgA antibodies and serum lysozyme were followed during the course of sensitization. The lung histology showed an increased number of intra-alveolar macrophages and leucocytes in sensitized mice. Interstitial peribronchiolar and perivascular infiltration of mononuclear inflammatory cells and a few granulomas were also detected. An increase in the prevalence as well as titers of IgG and IgA antibodies was recorded during sensitization. An elevation in serum lysozyme level was also observed in sensitized mice. The lung histology of control animals was essentially normal and no increase in antibody titers or lysozyme levels was detected. Intranasal application of antigen prepared from Thermoactinomyces vulgaris seems to produce in mice allergic alveolitis resembling human farmer's lung.