PubMed Health⌕ Search

Biomedical subjects

A Scheynius

Publications and source records attributed to A Scheynius.

At least 109 records · Page 6Linked to original sources
PubMed1995

Quantitative and three-dimensional analysis of human Langerhans cells in epidermal sheets and vertical skin sections.

We used confocal laser scanning microscopy to analyze and compare Langerhans cells (LCs) in normal skin of six subjects. Acetone-fixed epidermal sheets and 25-microns vertical skin sections were incubated with fluorescein isothiocyanate-conjugated mouse monoclonal antibodies directed against HLA-DR. An individual threshold setting algorithm compensating for the differences in background fluorescence was applied to identify specific fluorescence. No statistically significant difference was found in the relative volume of epidermal HLA-DR reactivity between epidermal sheets (14 +/- 5%) and vertical skin sections (13 +/- 6%) or in the number of dendrites per HLA-DR+ LCs (7.8 +/- 3.1 and 5.9 +/- 3.1, n = 58, respectively). However, statistically significant higher background intensity was found in vertical sections than in epidermal sheets. Three-dimensional (3D) reconstructions of HLA-DR+ LCs revealed a concentration of HLA-DR to one or a few intracellular vesicles in 42 of 58 analyzed LCs in epidermal sheets and in 18 of 58 analyzed LCs in vertical sections. Direct contact between dendrites from different LCs was not found. The results indicate that both skin forms are suitable for quantitative studies. Owing to less background intensity and larger tissue volume, detailed 3D analysis of LCs is preferably performed on epidermal sheets rather than on vertical sections.

Adult↗
PubMed1994

Evidence of a local intestinal immunomodulatory effect of sulfasalazine in rheumatoid arthritis.

OBJECTIVE: To analyze whether the intestinal mucosa in rheumatoid arthritis (RA) is immunologically abnormal and whether sulfasalazine (SSZ) possesses any local intestinal immunoregulatory effect. METHODS: Lymphocyte subpopulations and HLA-DR expression were evaluated in biopsy specimens from the duodenal-jejunal mucosa and in peripheral blood samples obtained from 17 patients with RA, both before and after 16 weeks of SSZ treatment. The same mucosal assays were also performed in 7 controls. RESULTS: The mucosa of the small intestine in RA patients showed no differences in morphology, HLA-DR expression, or the amounts and distribution of CD3+, CD4+, CD8+, and gamma/delta + lymphocytes compared with the control group. However, there was a reduction in mucosal CD3+ and gamma/delta + lymphocyte numbers after SSZ therapy, which did not correspond to a change in peripheral blood CD3+ lymphocyte number. SSZ treatment also tended to diminish the peripheral blood CD4+:CD8+ cell ratio (P = 0.05). CONCLUSION: No signs of inflammation or immunologic abnormalities were seen in RA duodenal-jejunal mucosa. In this part of the intestine, however, SSZ exerted immunoregulatory effects that were not encountered in the peripheral blood.

Adjuvants, Immunologic↗
PubMed1994

Sawdust-induced inflammatory changes in rat lung: effects on alveolar and interstitial cells in relation to time.

Exposure to sawdust and its contaminants, e.g., terpenes, may cause respiratory tract and lung parenchymal inflammation. To monitor these changes over time. Sprague-Dawley rats were exposed at one occasion to 2.5 mg sawdust or saline by intratracheal instillation. Flow cytometry analyses were done on bronchoalveolar lavage (BAL) cells. Lung tissue specimens were analyzed histologically and immunohistochemically. After one week, the number of BAL polymorphonuclear leukocytes was increased (P < 0.05, N = 8), followed at six weeks by increases of macrophages and lymphocytes (both P < 0.01, N = 8). Enhanced expressions of class II antigens and complement receptors on macrophages after one week were even more pronounced at six weeks, indicating cellular activation. The BAL findings, also including increased (P < 0.001, N = 8) concentrations of hyaluronan with progressing changes over time, confirmed the signs of inflammation, as did the histological analysis of the lung tissue specimens with an accumulation of polymorphonuclears, macrophages, and hyaluronan in the interstitium.

Animals↗
PubMed1994

Effect of sulphasalazine on gastrointestinal microflora and on mucosal heat shock protein expression in patients with rheumatoid arthritis.

This study was performed in order to elucidate a possible association between mucosal heat shock protein expression, the gastrointestinal microflora and disease activity in 17 patients with RA before and after 16 weeks of sulphasalazine (SASP) treatment. The duodenal-jejunal mucosal binding of the monoclonal antibody ML30, recognizing the 65 kDa heat shock protein of mycobacteria, was increased (P = 0.048) in the untreated RA patients compared to controls, but did not correlate to disease, activity or microflora and was not altered by SASP therapy. There was no convincing evidence for bacterial overgrowth in the jejunum and the faecal microflora was normal. SASP treatment altered the faecal microflora, with significant reductions of the total aerobic bacteria, Escherichia coli and Bacteroides, and increased numbers of Bacillus. SASP had only minor effects on the jejunal microflora. A high carriage frequency of Candida albicans was found in saliva and the counts correlated negatively with the unstimulated whole salivary secretion rate. These results suggest that the gut may be involved in the aetiopathogenesis of RA but do not substantiate the hypothesis that the anti-rheumatic effects of SASP are mediated via its anti-microbial properties. However, the possibility that a micro-organism, not detected in this study, may be of crucial importance in RA, cannot be ruled out.

Adult↗
PubMed1994

Quantitative and 3-dimensional analysis of Langerhans cells in basal cell carcinoma. A comparative study using light microscopy and confocal laser scanning microscopy.

We have analysed Langerhans cells (LCs) in basal cell carcinoma (BCC) and in healthy skin in 15 patients, using three different techniques: light microscopic examination of horizontal sheets, and of 6-micron-thick vertical skin sections, and confocal laser scanning microscopy (CLSM) of 25-micron-thick vertical sections. The use of CLSM enables both a quantitative and a three-dimensional (3-D) analysis of the cells in the same tissue volume. A statistically significant reduction in the relative volume of epidermal CD1a reactivity confined to tumour areas was found with CLSM. This difference was confirmed when the number of LCs in horizontal sheets were counted. In contrast, no significant reduction in epidermal CD1a+ cells was found in thin vertical sections. This is probably due to the smaller tissue sample examined, and to variations in the number of CD1a+ cells, with less cells directly overlying the tumour nests. The ratio of CD1a-expressing cells in the epidermis/dermis was significantly reduced in BCCs, compared with healthy looking skin. Few LCs were observed in tumour nests, but they were numerous in the surrounding stroma of the dermis. Three-dimensional reconstructions of CD1a+ cells in BCC revealed striking morphological changes; they had a reduced number of dendrites, and these were often short and had few branches. The results demonstrate that CLSM is a suitable technique for quantitative and morphological analysis of CD1a-expressing cells in the skin. We suggest that the alterations in LC numbers, distribution and morphology in BCC most probably are secondary to changes in the local environment.

Adult↗
PubMed1994

Germline-encoded IgG antibodies bind mouse cartilage in vivo: epitope- and idiotype-specific binding and inhibition.

Autoantibodies specific for type-II collagen (CII) occur in mice and rats with collagen-induced arthritis (CIA). The binding in vitro and in vivo of mouse monoclonal antibodies (MoAbs) specific for separate epitopes in CII have been investigated. Two-day-old mice were injected intraperitoneally (i.p.) with the anti-CII antibody CIID3 in both unlabelled and biotinylated form. It was found that antibodies binding to the same epitope in CII in vivo can inhibit others from binding in an epitope-specific fashion. The binding in vivo and in vitro of anti-CII antibodies could be inhibited also by an anti-idiotypic rat antiserum produced against the D3 antibody. The anti-idiotypic antiserum inhibited the binding of the antibody D3 and the idiotypically related antibody C2. The cDNA's of anti-CII antibodies D3, C2, and F4 were sequenced and found to contain germline encoded V-genes, apparently without somatic mutations. The variable heavy chain of D3 and C2 both expressed the same VH rearrangement, confirming that they share idiotypes. This report demonstrates that CII-specific germline-encoded IgG autoantibodies bind specifically to normal cartilage in vivo via their combining site.

Amino Acid Sequence↗
PubMed1994

Identification of allergen components of the opportunistic yeast Pityrosporum orbiculare by monoclonal antibodies.

The yeast Pityrosporum orbiculare (P. orbiculare) is a member of the normal human cutaneous flora, but it is also associated with several clinical manifestations of the skin. We have previously observed IgE-binding components in P. orbiculare extracts, using sera from patients with atopic dermatitis. In the present study, we raised several monoclonal antibodies (MoAbs) against P. orbiculare to characterize some of its antigens, and used Candida albicans (C. albicans) as a control. We obtained several IgG1 MoAbs which specifically recognized P. orbiculare in ELISA. Two of these were selected for immunoblotting studies on P. orbiculare, and two patterns of reactivity emerged. Firstly, one MoAb showed a distinct band at a molecular mass of 67 kDa. In the second pattern, a sharp band at about 37 kDa appeared. In contrast, the IgM antibodies raised reacted with a 14-kDa component; but they reacted with C. albicans in addition to P. orbiculare. The IgG1 antibodies seemed to react with proteins, as their ability to react in ELISA with extract pretreated with protease was greatly reduced. In contrast, IgM MoAbs were much less affected, suggesting that they recognized nonprotein components. To determine whether these MoAbs-binding components were also recognized by human IgE, we adopted a radioimmunoassay (RIA) using the MoAbs as catcher antibodies. Both the 67-kDa and the 37-kDa components were IgE-binding proteins. P. orbiculare RAST positive sera were scored as positive in the RIA, whereas the control serum was not.

Allergens↗
PubMed1993

CD44 is necessary for optimal contact allergic responses but is not required for normal leukocyte extravasation.

The in vivo administration of certain monoclonal antibodies (mAbs) against the adhesion receptor, CD44, into normal mice induces both a modulation of CD44 from the surface of peripheral lymphocytes, and a concomitant increase in the amount of soluble CD44 in the serum. CD44-negative lymphocytes isolated from anti-CD44-treated mice exhibit normal homing patterns upon adoptive transfer, and are capable of reexpressing CD44 upon activation. The treatment of haptensensitized mice with anti-CD44 mAb inhibits their ability to mount a cutaneous delayed-type hypersensitivity (DTH) response within the first 24 h after hapten challenge. This inhibition reflects a block in both the edema and leukocyte infiltration of the cutaneous site of DTH, whereas the extravasation and accumulation of leukocytes in the draining lymph nodes progress normally. After 72 h, the leukocytes that extravasate into the site of antigen challenge express CD44. These results indicate that CD44 is not necessary for normal leukocyte circulation but is required for leukocyte extravasation into an inflammatory site involving nonlymphoid tissue.

Animals↗
PubMed1993

Reduced contact sensitivity reactions in mice treated with monoclonal antibodies to leukocyte function-associated molecule-1 and intercellular adhesion molecule-1.

We have investigated the effect of the administration of mAb against leukocyte function-associated molecule-1 (CD11a/CD18) and intercellular adhesion molecule-1 (CD54) on the delayed-type hypersensitivity reaction in 2,4-dinitro-1-fluorobenzene-sensitized CD2F1 mice. An i.p. injection of the mAb FD441.8 against CD11a at the time of ear challenge led to an almost complete inhibition of ear swelling compared with control animals. Administration of anti-CD54 mAb, 3E2 or YN1/1.7.4, before challenge, resulted in approximately 50% reduction of the delayed-type hypersensitivity response. The decrease in ear swelling reflected a profound inhibition of the edema and the cell infiltration in ears from animals treated with anti-CD11a, and a partial inhibition with anti-CD54 treatment. In addition, the threefold increase in the number of cells recovered from the draining lymph nodes 24 h after challenge in sensitized mice injected with normal IgG was ablated in mice treated with anti-CD11a and partially reduced in anti-CD54-treated animals. Immunohistochemistry and flow cytometry analysis demonstrated that the in vivo administered anti-CD11a mAb was associated with the surface of the majority of the cells in the lymph nodes 24 h after injection and challenge, whereas the anti-intercellular adhesion molecule-1 mAb reacted preferentially with the vascular endothelium. It is concluded that leukocyte function-associated molecule-1 and intercellular adhesion molecule-1 contribute to the generation of an optimal delayed-type hypersensitivity response.

Animals↗
PubMed1993

Induced expression of heat-shock protein on biliary epithelium in patients with primary sclerosing cholangitis and primary biliary cirrhosis.

In both primary sclerosing cholangitis and primary biliary cirrhosis it is supposed that immunological mechanisms are involved in the progressive destruction of the bile ducts. The aberrant expression of human leukocyte antigen-DR in the bile ducts of patients with these disorders enables the biliary epithelium to present putative antigens to the surrounding lymphocytes; however, no such antigen has been identified. Heat-shock proteins have been implicated in the pathogenesis of various immunological destructive disorders. Liver biopsy specimens from patients with primary biliary cirrhosis (n = 10) and primary sclerosing cholangitis (n = 13) were compared with those from patients with chronic hepatitis C infection (n = 5) and alcoholic cirrhosis (n = 4) and from normal controls (n = 6). Liver sections were investigated by means of immunohistochemical study using a mouse monoclonal antibody, ML30, directed against the 65-kD heat-shock protein of Mycobacterium, with monoclonal antibody against human leukocyte antigen-DR and with the monoclonal antibody Identi-Tr TCR delta 1, which recognizes a determinant on the delta-chain of the gamma/delta form of the human T-cell receptor. Human leukocyte antigen-DR expression was found on the biliary epithelium of all primary sclerosing cholangitis and primary biliary cirrhosis patients but not on bile ducts from patients with alcoholic cirrhosis or chronic hepatitis C infection or those from normal controls. The biliary epithelium reacted with ML30 in 9 of 10 primary biliary cirrhosis patients and in all primary sclerosing cholangitis patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Intestinal distribution of hyaluronan in small bowel allografting in the rat.

Hyaluronan (hyaluronic acid; HA) was demonstrated and quantified in small bowel tissue at different times after small bowel transplantation. Semiallogeneic or semisyngeneic rat models were used to elicit either unidirectional graft rejection or graft-versus-host disease (GVHD). In normal rat small bowel, HA was present in the villous lamina propria and around medium-sized vessels in the interstitium of the crypt area. During graft rejection a cellular infiltrate and edema appeared in the lamina propria in the crypt area where an accumulation of HA was also demonstrated. There was progressive accumulation of HA in the small bowel during rejection, and on day 6 there was a threefold increase compared to the values in syngeneic grafts. The increase in tissue HA was paralleled by an increase in the total water content of the rejecting graft. In specimens from animals suffering from GVHD, no significant changes in water or HA content and distribution were observed until day 12. The data suggest that accumulation of HA might contribute to the pathophysiology of the transplantation edema and that HA might be of potential diagnostic value in differentiating between graft rejection and GVHD.

Animals↗
PubMed1993

The effect of immunotherapy on T-cell subsets in peripheral blood and bronchoalveolar lavage fluid in pollen-allergic patients.

The effect of immunotherapy (IT) on T-cell subsets in peripheral blood and bronchoalveolar lavage fluid (BAL) was examined in 15 patients with rhinoconjunctivitis and asthma caused by sensitivity to birch pollen. They were treated with IT for 3 years. Seven patients were treated with highly standardized birch-pollen extract (Pharmacia, Sweden). Eight untreated patients served as controls. Histamine challenge, blood sampling, and BAL were performed before (January, February), and at the peak of, the birch-pollen season (May). The subpopulations of T cells in peripheral blood and BAL fluid were investigated by immunocytochemistry and flow cytometry. During the birch-pollen season, the percentage of CD3+ and CD4+ cells of blood mononuclear cells in the IT patients increased significantly (P < 0.03 and P < 0.02, respectively). The percentage of CD8+ cells remained unaltered. In control patients, no changes of T-cell subsets in the peripheral blood were observed. T-cell subsets in BAL did not change during the season in relation to preseasonal values for either IT-treated or non-IT-treated patients.

Adolescent↗
PubMed1993

Absence of specific IgE antibodies in allergic contact sensitivity to formaldehyde.

Immunologic reactions are customarily divided into two broad categories, cell-mediated and antibody-mediated. An interplay between these two pathogenetic principles is indicated by reactions such as cutaneous basophil hypersensitivity, late-phase reaction, and cutaneous lesions indistinguishable from regular allergic contact dermatitis lesions after sensitization with IgE antibodies against certain haptens. In the present study, 23 patients with a history of a positive epicutaneous test to formaldehyde participated. On retest, 15 showed a positive reaction. Eight patients were Phadiatop positive, indicating an atopic diathesis, and eight had a history of or ongoing atopic dermatitis. On RAST test, only two, nonatopic patients had specific IgE antibodies to formaldehyde. In the cellular infiltrates of biopsies from epicutaneous test sites, cells reactive with monoclonal antibodies against IgE were found in positive and negative formalin tests, both in atopics and nonatopics, as well as in control biopsies from nonlesional skin. Double immunofluorescence staining experiments showed that IgE occurred on Langerhans' cells. The proportion of IgE-positive cells correlated to the level of serum IgE, but not to atopy. These cells were also found both in the epidermis and in the dermis in nonatopic patients. ICAM-1 occurred on keratinocytes in all patient groups. This study does not support the hypothesis that specific IgE antibodies are active in the pathogenesis of contact sensitivity to formaldehyde either in atopic or in nonatopic patients.

Biopsy↗
PubMed1993

Adenoid tissue lymphocyte subpopulations--evaluation of a quantitative analysis with flow cytometry.

Secretory otitis media (SOM) is a common childhood disease without a completely clarified etiology. A chronic inflammatory condition in the nasopharynx, presumably caused by an increased bacterial load, is one factor of probable etiological importance. In the present study a flow cytometric method for analysis of adenoid lymphoid cell populations was developed to facilitate quantitative comparisons between children with SOM and children without ear disease. Adenoids removed from 18 children due to adenoid hyperplasia and obstructive symptoms were studied. Results of the flow cytometric analysis correlated well with the findings from immunohistological studies of five of the adenoids. PCA-1 and CD25 were found to be good markers of increased cellular activity after non-specific stimulation in cell culture. It is concluded that the flow cytometric method is suitable for further quantitative analysis of adenoid tissue.

Adenoidectomy↗
PubMed1993

Quantitative and 3-dimensional analysis of Langerhans' cells following occlusion with patch tests using confocal laser scanning microscopy.

Quantitative and detailed 3-dimensional (3-D) morphological information can be obtained from the same tissue volume using a confocal laser scanning microscope (CLSM). In the present study, we used CLSM for evaluation of Langerhans' cells (LC) in human skin at 0 h, 24 h and 48 h following occlusion with patch tests for 48 h. The relative volume of epidermal CD1a reactivity was quantified with CLSM on 25 microns thick sections stained with indirect immunofluorescence. No statistically significant difference was found when comparing the values obtained on the biopsy specimens from occluded skin (n = 36) with those from non-occluded skin (n = 9). Nor were any statistically significant changes detected in the number of epidermal CD1a+ cells as determined with immunoperoxidase staining between occluded and non-occluded skin. The occlusion produced a transient mild inflammatory reaction with an induced expression of intercellular adhesion molecule-1 (ICAM-1) on keratinocytes and an increased number of CD3+ epidermal lymphocytes. In addition, 3-D reconstructions revealed spatial information on the distribution of LC dendrites towards the skin surface.

Adult↗
PubMed1993

Lack of concomitant expression of ICAM-1 and HLA-DR on bile duct cells from patients with primary sclerosing cholangitis and primary biliary cirrhosis.

In both primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) prominent infiltrates of lymphocytes surround the bile ducts, on which an abberrant expression of major histocompatibility complex class II antigens has been found, suggesting that the immune system is involved in the biliary destruction. Since the lymphocytes presumably must adhere to the bile ducts to initiate a cell-to-cell-mediated destruction, we have studied the expression of the lymphocyte function-associated antigen-1 (LFA-1) together with its ligand, the intercellular adhesion molecule-1 (ICAM-1), and the expression of HLA-DR, using immunoperoxidase staining of cryostat sections from patients with PBC (n = 10), PSC (n = 13), and normal healthy controls (n = 6). Most lymphocytes expressed LFA-1. ICAM-1 expression was found on hepatocytes from 9 of 10 PBC and 10 of 13 PSC patients but was not seen on hepatocytes from the controls. Hepatocytes expressing HLA-DR were only found in one patient with PBC. None of the septal bile ducts expressed ICAM-1, and only one PSC patient and three PBC patients expressed ICAM-1 on their interlobular bile ducts. The bile ducts in 22 of 23 patients, however, expressed HLA-DR. Proliferating bile ductules from two PBC patients and three PSC patients showed a concomitant expression of ICAM-1 and HLA-DR. None of the bile ducts from the controls expressed ICAM-1 or HLA-DR.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Local and systemic immune response in Helicobacter pylori-associated chronic gastritis before and after treatment.

Ten patients with Helicobacter pylori-associated chronic gastritis were given combination therapy for 6 weeks with a bismuth subnitrate-containing compound and bacampicillin. The eradication rate was 40% 6 weeks after the end of treatment. Two patients remained H. pylori-negative at long-term follow-up after 6 and 17 months; that is, H. pylori was only eradicated in 20% of the patients after long-term observation. By dot blot and immunoblotting both urease and an urease-associated heat shock protein (HSP62) were found to be specific and constant immunodominant H. pylori antigens. The immunohistologic pattern showed induced expression of HLA-DR and HSP62, but not of ICAM-1, in all but two biopsy specimens of gastric epithelial cells. This study suggests i) that long-term observation is important when evaluating the efficacy of anti-H. pylori therapy; ii) that the immune defense mechanisms in the gastric mucosa differ from those in inflammatory conditions affecting other organs, where ICAM-1 and HLA-DR seem to be governed by a common regulator; and iii) that the immunopathologic effects of H. pylori may be caused by autologous and/or bacterial HSPs, which act as triggering factors in the development and persistence of the chronic inflammation in the gastric mucosa.

Adult↗