Search PubMed⌕ Search

Biomedical subjects

A Scheynius

Publications and source records attributed to A Scheynius.

At least 127 records · Page 7Linked to original sources
PubMed1987

Amplification of T-cell response to PPD by epidermal cell suspensions containing HLA-DR-expressing keratinocytes.

The biological importance of the presence of class II transplantation antigens on highly differentiated epithelial cells such as keratinocytes in certain conditions, is still unknown. We have therefore investigated the antigen-presenting capacity of separated human epidermal cells obtained from tuberculin-reactive skin 6 days after intradermal injection of purified protein derivative (PPD). Earlier studies have shown a high percentage of HLA-DR-expressing keratinocytes at this time. Peripheral adherent blood cells were used as control stimulator cells and highly purified peripheral blood T lymphocytes as responder cells. The T-cell proliferation in response to PPD in the presence of autologous epidermal cells from normal and tuberculin-reactive skin was measured by [3H]thymidine incorporation on day 6. The latter cell population, 76-86% of which consisted of HLA-DR-expressing cells as judged by immunocytochemistry, induced a greater T-cell response to PPD than do normal epidermal cells. This discrepancy in the T-cell proliferation could not be explained by a difference in the numbers of anti-Leu 6 or anti-HLA-DQ-reactive Langerhans cells. The present data indicate that epidermal cell suspensions containing HLA-DR-expressing keratinocytes induce a greater T-cell response to PPD than do normal epidermal cells.

Adult↗
PubMed1987

Effects of monoclonal anti-T cell antibodies on rat cardiac allografts.

Monoclonal antibodies reactive with different T lymphocyte antigens were administered to rats receiving heart allografts. Ox 19 antibodies (directed to the rat Ly 1 equivalent) and Ox 8 antibodies (directed to the rat CD8 equivalent) both prolonged graft survival, whereas W3/25 (anti-CD4), Ox 6 (anti-Ia), and W3/13 (anti-pan T) antibodies did not affect graft rejection. Immunohistological studies were carried out on spleen and graft specimens in order to analyse further the mechanisms behind the prolongation of graft survival. The observed almost complete absence of Ox 8-reactive cells in the spleen after treatment with Ox 8 antibodies corroborates earlier observations that injection of moderate amounts of Ox 8 antibodies leads to complete elimination of suppressor/cytotoxic T cells from peripheral lymphoid organs and blood. The present data on graft survival therefore both support the notion that suppressor/cytotoxic T cells are involved in graft rejection, and suggest that these cells are not the only ones involved. An unexpected and as yet unexplained finding was that Ox 8-reactive molecules were found in large numbers on various inflammatory cells as well as on certain myocytes in the grafted hearts that had experienced a prolonged graft survival due to treatment with Ox 8 or Ox 19 antibodies.

Animals↗
PubMed1987

In vitro testing of contact sensitivity.

A new in vitro technique for the testing for contact sensitivity is described. The method is based upon the fact that in response to immunological stimuli, keratinocytes can start to synthesize and express class II histocompatibility antigens. Nickel sulphate (NiSO4) stimulated lymphocytes from nickel-sensitive persons, and the supernatant of these cells thus induced expression of HLA-DR on keratinocytes when co-cultured with autologous normal skin biopsies. This was in contrast to what was the case in healthy controls.

Dermatitis, Contact↗
PubMed1987

Enzyme-linked immunosorbent assay of H+,K+-ATPase, the parietal cell antigen.

Vesicular membranes, purified from porcine gastric mucosa and rich in H+,K+-ATPase, were used to establish an enzyme-linked immunosorbent assay (ELISA) for determinations of parietal cell autoantibodies. Results obtained with the ELISA correlated well with standard immunofluorescence determinations of parietal cell antibodies based on frozen sections of rat stomach. The ELISA however was about 10-fold more sensitive than the immunofluorescence method and had high specificity. Intra- and interassay coefficients of variation, determined with a patient sera of average positivity, were 5.5% and 18%, respectively. The ELISA detected antibody binding in 23 out of 26 sera from patients with known autoimmune atrophic gastritis, in five of 25 sera with autoimmune thyroiditis, in five of 20 sera from patients with Graves' disease, in three out of 20 sera from patients with atoxic nodular goitre, in six of 20 sera of patients with primary biliary cirrhosis, in two out of 20 sera of patients with active duodenal ulcer, in two out of 20 sera with detectable antinuclear antibodies, and in one out of 20 sera with detectable rheumatoid factor. Data determined by an ELISA based on a gastric vesicular membrane preparation of human origin correlated well (r = 0.79, P less than 0.001) to those obtained by the standard ELISA based on porcine membrane material. The assay should be well suited for routine determinations of parietal cell antibodies in investigations of autoimmune gastritis and multiple organ autoimmune endocrinopathies.

Adenosine Triphosphatases↗
PubMed1986

An immunologic and cultural study of Pityrosporum folliculitis.

In patients with Pityrosporum folliculitis the mean serum antibody titer against Pityrosporum orbiculare was significantly higher than in healthy control subjects (p less than 0.01). The mean number of P. orbiculare organisms per square centimeter cultured from normal-looking skin in patients was not significantly higher than the number cultured from normal-looking skin in control subjects. Results of prick tests against P. orbiculare extract were negative or weak, indicating that patients with Pityrosporum folliculitis had no type I hypersensitivity against P. orbiculare. Immunohistochemical staining of skin lesions showed perivascular dermal cell infiltrates near the hair follicles dominated by anti-Leu 3a-reactive T lymphocytes. Human lymphocyte antigens with the DR locus, but not those with the DQ locus, on keratinocytes were observed in one case.

Adult↗
PubMed1986

In vivo induction of Ia antigens on rat keratinocytes by gamma-interferon.

Recombinant rat IFN-gamma was found to induce Ia antigen expression on rat keratinocytes in vivo. Strong expression of Ia antigen on keratinocytes of rat ears was produced after intradermal injections of 10,000 U IFN-gamma once daily on 3 successive days. The expression was still pronounced 2 days after the last injection, but had disappeared 4 days later.

Animals↗
PubMed1986

Expression of HLA-DQ antigens on keratinocytes in Borrelia spirochete-induced skin lesions.

Skin biopsies were investigated with two different immunohistochemical techniques, thus revealing HLA-DQ antigens on HLA-DR-expressing keratinocytes in the late skin manifestations of a Borrelia spirochete infection. In the early skin lesions only HLA-DR antigens were present on the keratinocytes. The invariant gamma chain of class II transplantation antigens was observed on keratinocytes in 1:5 of the late cases. Upon penicillin treatment detectable HLA-DR and HLA-DQ antigens disappeared completely from the keratinocytes. Furthermore, the mononuclear cell infiltrates dominated by anti-Leu 1 and anti-Leu 3a-reactive cells and containing many cells with markers for activation (HLA-DR, HLA-DQ, transferrin, and interleukin 2 receptors) diminished markedly. The possibility that the expression of different class II transplantation antigens on keratinocytes might reflect separate functional demands of these cells or an altered immunological reactivity in the host, is discussed. The precise functional role of the temporary expression of the class II antigens on non-lymphoid cells, however, remains an enigma.

Acrodermatitis↗
PubMed1986

Phenotypic difference between allergic and irritant patch test reactions in man.

Cellular responses in allergic and irritant contact dermatitis were analysed in situ using an immunohistochemical double staining technique with the aim of uncovering phenotypical differences of diagnostic importance. Allergic and irritant patch test reactions were elicited in 9 individuals using the Finn chamber technique. Thirty-nine skin biopsies from these reactions and from petrolatum controls were obtained 4 to 20 days after the test applications. Cell infiltrates were present throughout the observation period in both allergic and irritant reactions, but were usually greater in the former. In both types of reaction, anti-Leu 3a reactive cells predominated over anti-Leu 2a reactive cells. HLA-DR expression on keratinocytes was found in 9 of 14 allergic reactions, but not in irritant reactions or control areas. HLA-DQ antigens were not detected on keratinocytes. The presence of HLA-DR antigens on keratinocytes may reflect an immunological response of the allergic reactions, and thus be of diagnostic relevance.

Adult↗
PubMed1986

Expression of Class II transplantation antigens by epithelial cells in oral candidosis, oral lichen planus and gingivitis.

Biopsies from normal oral mucosa and oral mucosa affected by candidosis, lichen planus or gingivitis were compared with respect to the expression of two Class II transplantation antigens, HLA-DR and HLA-DQ, by epithelial cells and the relationship of these antigens to the distribution and frequency of T-lymphocytes. Indirect immunohistochemistry with different mouse monoclonal antibodies was used on frozen and acetone-fixed sections. To evaluate the results, a score system based upon the expression of the Class II transplantation antigens by epithelial cells and the frequency of T-lymphocytes was used. In oral candidosis there was a marked expression of HLA-DR antigens throughout the epithelium. In addition, this type of epithelium was the only one that expressed HLA-DQ antigens. An intense intraepithelial infiltration of T-lymphocytes was observed. Oral lichen planus and gingivitis did, to a much lesser extent, cause the expression HLA-DR antigens by the epithelial cells. In both lesions, the number of T-lymphocytes within the epithelium did not exceed the number found in epithelium of normal mucosa. In these types of lesions, the subepithelial infiltrate varied in intensity but was mainly composed of T-lymphocytes reactive with anti-Leu 3a antibodies. The results of the present study imply that epithelial expression of the two different Class II antigens are related to the frequency of the T-lymphocytes and to the proximity of these cells to the epithelial cells.

Adult↗
PubMed1986

Cell surface expression of invariant gamma-chain of class II histocompatibility antigens in human skin.

A rat monoclonal antibody (McAb 21:9) reactive with the human invariant gamma-chain of class II major histocompatibility complex (MHC)-encoded antigens was isolated and was shown to react with the carbohydrate-carrying, COOH-terminal part of the gamma-chain. The McAb 21:9 binds to a molecule that is identified as the gamma-chain for the following reasons: it has an apparent m.w. of 33,000, similar to that of the gamma-chain; it has a two-dimensional gel migration pattern identical to that of the gamma-chain; and it associates with immature, but not processed class II antigens. When used for immunohistochemical staining on sections of normal human skin, only dendritic, class II MHC antigen, and anti-Leu-6 reactive Langerhans cells are labeled in the epidermis. HLA-DR-expressing keratinocytes present in the tuberculin reaction, cutaneous T cell lymphoma, and lichen planus, however, did not react with the anti-gamma-chain antibody, nor with a HLA-DQ-reactive antibody. Cell surface expression of the gamma-chain was observed on 1 to 3% of normal viable epidermal cells in suspension. By using double indirect immunofluorescence, it was possible to demonstrate the simultaneous binding of anti-gamma-chain, anti-HLA-DR, anti-Leu-10, and anti-Leu-6 antibodies, respectively, on the same cells, thus confirming their identity as Langerhans cells. The presence of the gamma-chain on the surface of the immunocompetent Langerhans cells may indicate that the cell surface, not the cytoplasm as has been suggested, is the site of the primary function of the gamma-chain.

Adult↗
PubMed1986

Induction of Thy-1 antigen on murine keratinocytes.

In normal murine epidermis Thy-1 antigen is known to be strongly expressed on a dendritic population of bone marrow derived cells lacking Ia antigens and faintly on keratinocytes. We now report on the induction of pronounced expression of Thy-1 antigen on keratinocytes by immunological stimuli as well as by chemical irritation and wounding. In contrast the induction of Ia antigens on keratinocytes is more restricted. It has been suggested that the dendritic Thy-1+ cells can suppress an immune response initiated by Ia antigen expressing Langerhans cells. The balance within epidermis between up- and down-regulation of immune reactions, may be even more complex if also keratinocytes expressing Thy-1 and/or Ia antigens should prove to participate.

Animals↗
PubMed1986

Distribution of interleukin-2 receptor bearing lymphocytes in the skin. A comparative study of allergic and irritant contact dermatitis, tuberculin reaction and cutaneous T cell lymphoma.

The tissue distribution of T cells and interleukin-2 receptor bearing (Tac+) lymphocytes was studied immunohistochemically in frozen sections of biopsies from inflamed skin. In skin lesions caused by irritant or immunologic stimuli, relatively few (less than 5%) of the total dermal infiltrating T cells were Tac+, but in both types of conditions the Tac+ cells showed a predeliction for the epidermis. In skin lesions from patients with cutaneous T cell lymphoma a relatively high proportion of dermal T lymphocytes were Tac+. Tac+ as well as Tac- T lymphocytes may thus migrate to a tissue secondary to several different stimuli. The demonstration of a non-random distribution of Tac+ lymphocytes in the non-malignant inflammatory conditions in the present study indicate that the epidermis may have a special role in the activation of T lymphocytes.

Antibodies, Monoclonal↗
PubMed1986

Fungal infections inducing HLA-DR but not HLA-DQ transplantation antigens on keratinocytes.

The phenotypes of infiltrating cells and class II transplantation antigens on keratinocytes in candida and dermatophyte lesions from 15 patients were analysed in situ with an immunohistochemical double staining technique combined with periodic acid-Schiff staining. In five out of ten biopsies from candida lesions and in one of five biopsies from dermatophyte lesions the keratinocytes expressed HLA-DR but not HLA-DQ antigens. The HLA-DR expression was patchy in all and most pronounced in two candida biopsies which also contained large infiltrates of anti-Leu 3a reactive T lymphocytes. The induction of detectable amounts of different class II antigens on keratinocytes might depend on the type of antigen, the magnitude and duration of the response elicited and/or the immunological state of the patient.

Adult↗
PubMed1986

Effects on murine T helper cell proliferation by DTH activated syngeneic epidermal cells.

Epidermal cells, obtained either from the site of a delayed type of hypersensitivity (DTH) reaction to 2,4-dinitro-1-fluorobenzene (DNFB) or from skin subjected only to painting with acetone: olive oil have been studied for their capacity to stimulate antigen specific T-lymphocyte proliferation. Small numbers of cells from the control, as well as from the DTH activated epidermis, presented collagen type II to a line of and a clone of collagen II specific T helper cells. Larger numbers of epidermal cells from DTH activated epidermis suppressed this T-cell proliferation compared to control epidermal cells. Phenotypic analysis showed an increased expression of Thy-1 antigen on epidermal cells from DTH lesions 3 days after provocation. It is suggested that epidermal cells may be involved in negative as well as positive feedback loops in conjunction with T-cell immunity. It would thus be of interest to study further whether the induced Thy-1 antigen expression on epidermal cells is of importance in a negative feedback system.

Animals↗
PubMed1985

Class II transplantation antigens in the late human skin tuberculin reaction.

The presence of class II transplantation antigens on keratinocytes and the phenotypes of the inflammatory cells in the late human skin tuberculin reaction were analysed with immunohistochemical double staining techniques in frozen sections of skin biopsies taken 10-45 days after intradermal purified protein derivative (PPD) injection. Dermal cell infiltrates decreased with time but were found throughout the observation period. Most of the cells in the perivascular infiltrates expressed HLA-DR antigens. Some of these cells are probably 'activated' macrophages, since they expressed OKM1 and OKT9 antigens in consecutive sections. Another less frequent cell population which reacted with RFD1 antibodies are presumably interdigitating cells. About half the perivascular cells were anti-Leu 3a-positive (T 'helper/inducer' phenotype). HLA-DR but not HLA-DQ antigens were detected on keratinocytes. This acquired expression of HLA-DR antigens on the epithelial cells disappeared between 17 and 30 days. If HLA-DR-expressing keratinocytes have immunoregulatory functions these might be different from those of other HLA-DR-expressing cell types that also express HLA-DQ molecules.

Epidermal Cells↗
PubMed1985

Treatment of therapy-resistant Sézary syndrome with Cyclosporin-A: suppression of pruritus, leukaemic T cell activation markers and tumour mass.

A patient with Sézary's syndrome resistant to conventional therapy was successfully treated with Cyclosporin-A (CyA) for 14 months. Pre-treatment in vitro studies showed that the leukaemic T cells were sensitive to therapeutic concentrations of CyA. The patient's pruritus disappeared promptly after 2 d of treatment. The positive effect of CyA on the pruritus was related to the dose and plasma concentrations of the drug. Analysis of leukaemic cell surface markers using monoclonal antibodies showed that episodes of pruritus were correlated with the appearance of cells expressing the T cell "activation" markers interferon- gamma (IFN-gamma) and HLA-DR. This indicated that CyA may control pruritus by suppressing the production/release of lymphokines. Immunohistochemical staining of repeated skin biopsies demonstrated a reduction of infiltrating T cells. Clinically, this was correlated with an improved skin status and a partial regress of palpable lymph node size. Apart from an initial reversible drop in the circulating helper/suppressor T cell ratio, the number of circulating Sézary cells was unaltered during CyA treatment. After 5 months, higher doses of CyA were needed to control symptoms, and this was correlated wit with partial drug resistance also in vitro.

Aged↗
PubMed1984

Human keratinocytes express HLA-DR antigens in the tuberculin reaction.

The cellular response in the human skin tuberculin reaction was studied with immunohistochemical double-staining techniques in frozen sections of skin biopsies taken 6 h to 8 days after intradermal PPD injections. Cell infiltrates were observed from day 2 onwards and increased in size up to 4 days. Most of the infiltrating cells reacted with anti-Leu 3a (T 'helper/inducer' phenotype) antibodies. In contrast to normal epidermis, not only Langerhans cells but also keratinocytes expressed HLA-DR antigens from day 4 onwards. The induction of HLA-DR antigens on keratinocytes may be secondary to T-cell activation. Since the HLA-DR expression on keratinocytes appeared late in the tuberculin reaction, the function may be to suppress rather than enhance the immune response.

Adult↗