Experimental T cell-mediated inflammatory reactions in the murine oral mucosa. II. Immunohistochemical characterization of resident and infiltrating cells

The nature and phenotype of infiltrating cells in DTH-like reactions elicited in the murine oral mucosa have been examined by routine histological and immunohistochemical procedures. During the first few hours that followed buccal challenge with the contact sensitizer oxazolone, a discrete lymphocytic reaction was disclosed in the oral mucosa of animals previously sensitized at skin sites, but was absent in animals that had been sensitized at buccal sites. The early lymphocytic reaction in the oral mucosa of skin-sensitized animals preceded the emergence of CD11+ polymorphonuclear cells (PMN) which was most prominent 8 h after hapten challenge and invaded the whole thickness of the oral epithelium. The PMN rapidly disappeared by 24 h. In contrast, early PMN infiltration was virtually absent in specimens from animals similarly challenged but that had been sensitized at local buccal sites. Irrespective of site of initial sensitization, inflammatory reactions developed in the oral mucosa, being maximal by 24 h. At that stage, CD11+ macrophages were the predominant cell type. Both CD4 and CD8 T lymphocytes were scattered in both lamina propria and epithelium, and their numbers were raised throughout the time period studied (2-168 h). IL-2 receptor expression was maximal 16 h post-challenge, and was paralleled by increased DNA synthesis in CD4+ and CD8+ cells, as demonstrated by paired immunohistoautoradiography. Focal accumulations of mononuclear cells containing IL-2 producing cells were readily detected as early as 2-3 h following local challenge with hapten in animals primed at skin but not at buccal sites. Maximal IL-2 staining was detected at 24 h irrespective of initial sensitization site. Interferon-gamma-producing cells were detected at 8 h post-challenge and remained increased during the first 24 h. MHC class II expression was detected on few oral mucosa cells during the first 4 h following hapten challenge, being mainly confined to dendritic-like cells. Consistent with increased numbers of macrophages, MHC class II expression was most intense in specimens obtained 8-24 h after hapten challenge. Thereafter, MHC class II expression was still observed in specimens obtained as late as 72 h, but was essentially associated with patches of basal keratinocytes. Taken together, these observations support the notion that the murine oral mucosa can serve as the site of expression of locally or remotely induced DTH reactions, but also indicate that the site of initial sensitization can profoundly affect the cellular composition of inflammatory reactions subsequent to local buccal challenge.

Alterations in the level of phosphotyrosine signal transduction constituents in human parotid tumors

Human parotid tumors were evaluated for the activation of the phosphotyrosine signaling pathway by Western blot, enzyme activity assay, and reverse transcriptase-polymerase chain reaction. Warthin's tumor and mucoepidermoid carcinomas had the greatest level of tyrosine phosphorylated proteins identified in plasma membrane fractions. These tumors, along with pleomorphic adenocarcinoma, showed high levels of membrane expression of the tyrosine kinase receptor, c-erbB-2, and phosphatidylinositol-3-kinase. Expression of the epidermal growth factor receptor was confined to normal tissue. The level of mRNA for c-erb was elevated only in mucoepidermoid carcinomas. Messenger RNA levels for ras were unchanged from control levels in all tumors, while the level of src mRNA was higher in the tumor samples than the normal parotid tissue. The activities of several signal transduction kinases, including protein kinase A and C were elevated in tumor tissue (7.7- to 18.9- and 0.4- to 3.7-fold higher, respectively), relative to surrounding normal tissue. While the level of glandular amylase was reduced (22%-0% of normal levels) in the tumor tissue, epidermal growth factor (EGF) and transforming growth factor-alpha (TGFalpha) content was dramatically higher in the neoplastic tissue (10- to 170-fold and 4.6- to 6.0-fold, respectively). These results suggest that with the presence of elevated levels of EGF, TGFalpha, and the oncoprotein receptor c-erbB-2 in the membrane of parotid tumors, cell proliferation and activation of the phosphotyrosine signal transduction pathway may involve autocrine stimulation through the expression of high levels of growth factor and receptor in the same tissue.

Immunohistological characteristics of periodontal lesions associated with Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans infections

In this study, various phenotypes of infiltrating cells in the periodontium adjacent to pockets harboring Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were evaluated. Furthermore, the pattern of class II antigen expression in the periodontal tissues was determined. Eight lesions were associated with the presence of P. gingivalis and 12 with A. actinomycetemcomitans. Predominant cells in the inflammatory infiltrate were T- and B-cells. In most biopsies T-cells dominated over B-cells. The proportion of P. gingivalis, but not of A. actinomycetemcomitans, was positively correlated to the total number of infiltrating cells in the tissue. A. actinomycetemcomitans sites demonstrated somewhat lower proportions of CD3+, CD4+ and CD19+ cells than P. gingivalis sites. However, the tendency of decreasing CD4+/CD8+ ratio with increasing number of A. actinomycetemcomitans indicates a local imbalance in immunoregulation. The frequency of class II antigen expression of both mononuclear and epithelial cells, a sign of immunological activation, was generally high.

Serum antibodies from patients with primary Sjögren's syndrome and systemic lupus erythematosus recognize multiple epitopes on the La(SS-B) autoantigen resembling viral protein sequences

The aim of this study was to investigate the epitope recognition pattern of La(SS-B) autoantibodies in sera from patients with Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE) using overlapping synthetic decapeptides on solid phase. Eighty different decapeptides with five amino acids overlap from the human La(SS-B) autoantigen were synthesized on cellulose paper using F-moc chemistry. Tests were performed with 14 SS and six SLE sera. The results showed that the immune response to the La(SS-B) oligopeptides was restricted and unique for each individual with no particular pattern typical for each of the two diseases, apart from the fact that SLE sera gave positive reaction with fewer peptides. Regions within the N- and C-termini harboured most of the positive sequences. The authors specifically addressed the possibility of a viral aetiology for disease development or autoantibody generation. In this context the most frequently recognized linear epitopes on the La(SS-B) autoantigen showed sequence similarities with proteins from a range of ubiquitous human viruses, in particular from the herpes virus group. The La(SS-B) autoantibodies may thus be generated through molecular mimicry.

Peripheral blood in Sjögren's syndrome does not contain increased levels of T lymphocytes reactive with the recombinant Ro/SS-A 52 kD and La/SS-B 48 kD autoantigens

Patients with Sjögren's syndrome (SS) frequently have anti-Ro/SS-A and anti-La/SS-B autoantibodies. The aim of this study was to investigate if these patients have peripheral blood lymphocytes (PBL) secreting IFN-gamma after short-term cultivation in the presence of Ro/SS-A and La/SS-B antigens. The frequency of PBL secreting IFN-gamma was examined in 12 SS patients and 11 healthy controls. The enzyme-linked immunospot (ELISPOT) assay was performed after 48 hours cultivation of PBL in the presence of recombinant Ro 52 kD protein or recombinant La 48 kD protein. The number of unstimulated IFN-gamma secreting cells in the SS patient group was not significantly different from that of the control group. Moreover, no increase in the number of IFN-gamma secreting cells after Ro/SS-A and La/SS-B stimulation was detected in the two groups. Thus, T cells reactive with the recombinant Ro 52 kD and La 48 kD proteins do not occur with any increased frequency in peripheral blood of SS patients.

Effect of inferior alveolar nerve axotomy on immune cells and nerve fibres in young rat molars

Denervation has been a useful approach to the investigation of interactions between nerve fibres and the pulp-dentine complex. Information on the immunological implications of axotomy is still lacking. The effect of axotomy on CD43+, CD4+, CD11b+ and I-A antigen-expressing cells in both the distal segment of the cut inferior alveolar nerve and in the first molar pulp of young rats was evaluated. Nerve fibres immunoreactive to protein gene product (PGP) 9.5, the neuropeptides substance P and calcitonin gene-related peptide (CGRP), and neuropeptide Y were visualized also by use of the avidin-biotin peroxidase complex method. Recruitment of macrophages was found in the distal segment of the sectioned inferior alveolar nerve 2 days after axotomy, with a further increase in number during the 6-day observation period. However, in the dental pulp, the number of CD43+, CD4+, CD11b+ and I-A antigen-expressing cells was almost unaffected. An almost complete sensory denervation of the first mandibular molar pulp was obtained 2 days after axotomy. After 6 days, the mesial part of the coronal pulp still remained denervated, while regenerated nerve fibres had reached both the root pulp and the distal part of the coronal pulp. Nerve fibres immunoreactive to neuropeptide Y were slightly reduced in density 2 days after axotomy, and after 6 days the localization of neuropeptide Y-immunoreactive fibres was changed compared to the control, with fibres also distributed in the odontoblast layer close to dentine. Hence, following axotomy in young rats, an almost complete sensory denervation is achieved in the first molar, whereas nerve fibres immunoreactive to neuropeptide Y change their distribution pattern, with fibres located close to the dentine after 6 days. Due to the almost unchanged number and distribution of immunocompetent cells in the pulp after axotomy, the young rat molar pulp may represent a suitable and useful experimental model to study neuro-immune interactions.

Short-term administration of selected anti-T-cell receptor V beta chain specific MoAb reduces sialadenitis in MRL/lpr mice

Sialadenitis develops spontaneously in MRL/Mp mice bearing a lymphoproliferative gene, lpr (MRL/Mp-lpr/lpr). Based on recent observations of an oligoclonal expansion of T-cell receptor (TCR) expressing V beta chain families (V beta 4, V beta 8.1,2, V beta 10b) in salivary glands of these mice we have initiated selective antibody therapy. Treatment with monoclonal antibodies (MoAb) specific for T cells expressing a mixture of TCR V beta 4, V beta 8.1,2 and V beta 10b was applied to MRL/lpr mice before and after the spontaneous development of sialadenitis. The in vivo treatment with V beta 4, V beta 8.1,2 and V beta 10b MoAb did not prevent the development of sialadenitis. However, in animals with established sialadenitis, treatment with the MoAb significantly decreased the inflammation compared with the control groups. Immunohistochemical staining of cell phenotypes demonstrated a change in the ratio of CD4/CD8 in the animals with established sialadenitis. Altogether, these findings illustrate that it is possible to modulate sialadenitis and infiltrate cell phenotypes in vivo in MRL/lpr mice with specific anti-TCR V beta MoAb treatment.

Recruitment of immunocompetent cells after dentinal injuries in innervated and denervated young rat molars: an immunohistochemical study

The dental pulp represents a peripheral end-organ deprived of a collateral nerve supply. After inferior alveolar nerve (IAN) axotomy, rat molar pulp is denervated over a period of at least 6 days. Therefore, rat molar pulp was used as an experimental model to study the effect of sensory nerve fibers on influx of immunocompetent cells after dentinal injury. In the present study we performed a quantitative analysis of CD43+, CD4+, CD11b+, and I-A antigen-expressing cells subjacent to dentinal cavities in denervated and innervated first mandibular molars. For visualization of nerve fibers, antibodies to protein gene product (PGP) 9.5, the sensory neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP), and the sympathetic neuropeptide Y (NPY) were used. Immunohistochemistry was performed by the avidin-biotin-peroxidase method. In the innervated teeth, a correlation between increased sensory nerve density and influx of immunocompetent cells was found. Compared to the contralateral innervated molars, a significant reduction in recruitment of immunocompetent cells was found in the denervated pulp tissue subjacent to the dentinal cavities. The rat molar represents a unique model to illustrate the influence of sensory nerves and neuropeptides on inflammation and recruitment of immunocompetent cells.

Spontaneous gingival antibody production to Fusobacterium nucleatum outer membrane in patients with adult periodontitis

The local antibody response to Fusobacterium nucleatum outer membrane (FnOM) was analyzed in patients with adult periodontitis (AP) at the single cell level. Furthermore, we analyzed whether periodontal hygienic treatment could alter the antibody response. The number of IgG- and IgM-producing cells were investigated in gingival samples collected from 20 patients with AP. The patients were divided into 2 groups, before (BT, n = 9) and after (AT, n = 11) periodontal hygienic treatment. Four healthy gingival samples were used as controls. The results obtained showed that local antibody production against FnOM occurred in gingiva of patients with AP, but not in healthy gingiva. The IgG anti-FnOM was the predominant isotype observed. However, there was no statistically significant difference between the BT and AT groups. These results indicate that periodontal hygienic treatment was not sufficient to alter significantly the number of IgG- and IgM-secreting cells present in gingival tissue of AP patients, but it promoted a reduction of IgG anti-FnOM secreting cells. The presence of anti-FnOM antibodies in AP but not in control patients indicates that this bacteria may play a role in the pathogenesis of periodontal disease.

Effects of calprotectin in avridine-induced arthritis

Plasma levels of calprotectin correlate with disease activity and clinical assessments of arthritis in various rheumatic diseases, and high levels have been demonstrated in the synovial fluid of patients with rheumatoid arthritis. However, the role of calprotectin in rheumatic inflammation is unclear. The purpose of the present study was to investigate potential intra-articular effects of calprotectin. Calprotectin was injected into joints of healthy male Lewis rats and into joints of rats in the latency period before onset of avridine-induced arthritis. In addition, a group of animals had IgG antibodies to rat calprotectin injected into joints before onset of avridine-induced arthritis. Injection of 0.2 or 10 micrograms calprotectin into the ankles of healthy male Lewis rats resulted in histologically minor and reversible inflammatory changes, but without any circulating antibodies to calprotectin. Furthermore, animals with 40 micrograms calprotectin injected into ankles before the expected onset of avridine-induced arthritis had lower scores for cellular infiltration than were seen in control joints. This difference did not quite reach statistical significance in the two-sided test used. However, the induced arthritis increased in joints injected with IgG antibodies to calprotectin. These findings may indicate that increased local concentrations of calprotectin are partially protective against avridine-induced arthritis. In contrast, reduced local concentrations appear to exacerbate the severity of arthritis. Calprotectin may thus be involved in the regulation of inflammatory processes in joints.

Avridine-induced arthritis in rats; a T cell-dependent chronic disease influenced both by MHC genes and by non-MHC genes

Avridine is a potent synthetic adjuvant that can induce arthritis is most rat strains. The clinical appearance and histopathology of avridine-induced arthritis show great similarity to other arthritis models such as collagen-induced arthritis. In LEW and DA rats the avridine-induced arthritis is severe and long lasting. To investigate a possible genetic influence on the disease we compared LEW, DA and E3 rats, which are of different genetic origins, for their ability to develop arthritis after injection of a low dose of avridine (1.5 mg/rat). The E3 rat was shown to be resistant, whereas all of the DA rats developed arthritis. Recombinant inbred strains derived from DA and E3 parentals varied in susceptibility to avridine. Only strains sharing RT1av1 with DA developed arthritis, indicating a role for the MHC genes. The MHC association was further analysed in a series of Lewis congenic strains using the 1.5 mg avridine dose. All strains developed arthritis. LEW.1C and LEW.1W developed only acute arthritis, whereas LEW.1A, LEW, LEW.1D, LEW.1N and LEW.1F developed chronic arthritis. In particular, the LEW.1F rats developed a chronic severe arthritis of high incidence. The chronic arthritis showed an active, erosive joint inflammation several months after induction. Nude rats are resistant to avridine-induced arthritis, indicating a T cell dependence of the disease which supports the importance of MHC. However, non-MHC genes are also crucial to arthritis development. Recombinants between DA and E3, sharing RT1av1 with DA, showed either a lower incidence or a lower severity of disease than the DA rats. The E3 rat and the recombinants with RT1u were completely resistant, whereas LEW.1W, also RT1u, were highly susceptible.

Systemic and mucosal antibody responses to group B streptococci following immunization of the colonic-rectal mucosa

The cervico-vaginal mucosa is poorly designed for inducing a mucosal immune response, but it can effect such a response evoked at other mucosal sites. This study was undertaken to determine whether colonic-rectal immunization with group B streptococci (GBS) might induce a local cervico-vaginal immune response. Mice were immunized with either fragmented GBS rectally, whole GBS rectally, or whole GBS subcutaneously. Cholera toxin (CT) was used as an adjuvant for the rectal immunizations. Following colonic-rectal immunization with whole GBS, the mean anti-GBS IgA antibody level in vaginal secretions was 735 kU/ml, with individual values reaching 3480 kU/ml. Corresponding levels of IgA antibodies never exceeded 10 kU/ml in serum and intestinal secretions, or 90 kU/g in feces. In vaginal secretions IgA antibodies to GBS also constituted a much larger fraction of total IgA than in serum, intestinal secretions and feces. Immunizations with fragmented GBS produced much lower IgA responses. Anti-GBS IgA response at the inductive site in the colon-rectum was not significant, as opposed to a strong anti-CT IgA response. Except in serum, the anti-GBS IgG responses to colonic-rectal immunizations were generally low, or absent. The results may provide a basis for the development of mucosal vaccines against GBS-infection.

Immunocompetent cells adjacent to stainless steel and titanium miniplates and screws

Subepithelial soft tissue and bone obtained from the implant bed in the vicinity of stainless steel and titanium miniplates and screws were evaluated with respect to the presence of immunocompetent cells. The study included tissue specimens from 19 patients, in whom the implants (14 stainless steel and 5 titanium) had been in situ for more than 6 months. The ABC (avidin-biotin-complex) immunoperoxidase staining technique using monoclonal antibodies defining T lymphocytes (CD3+), macrophages (CD11c+) and Class II MHC (HLA-DR) was performed on EDTA demineralized, frozen bone tissue, and on fresh frozen soft tissue specimens. The results showed scattered T lymphocyte clusters, small numbers of macrophages and abundant expression of HLA-DR in the soft tissue adjacent to both stainless steel and titanium implants. There was no substantial difference in tissue reactions between implants of the two materials. The demineralized bone sections disclosed presence of immunocompetent cells in the connective tissue lining the periphery of the screw holes. Metal particles were seen in both the soft tissue and the bone specimens. We conclude that a mild tissue reaction takes place in the vicinity of miniplates and screws of stainless steel and titanium, and that the intensity of the reaction indicates that the implants are well tolerated by the host tissue.

Calprotectin levels in oral fluids: the importance of collection site

Calprotectin is a major protein of granulocytes and monocytes with antimicrobial properties, and is released during activation or cell death. In the present study the levels of calprotectin in various oral fluids were analyzed in 12 healthy adults using different collection devices. Parotid saliva, stimulated whole saliva and "mucosal transudate" were collected and analyzed by enzyme-linked immunosorbent assay (ELISA). The results showed mean concentrations of 3.2, 22.0 and 40.9 mg/l in the respective oral fluids, illustrating great variation of calprotectin levels between different oral fluids. The results are in accordance with the composition of these saliva samples; the lowest calprotectin level was obtained in parotid saliva, which contains the purest secretion. These findings illustrate the importance of careful sampling procedures. The levels of salivary calprotectin are markedly influenced by the site of collection.

Parenteral influenza vaccination induces a rapid systemic and local immune response

The kinetics of the local immune response in the upper respiratory tract to parenterally administered inactivated split trivalent influenza vaccine were examined in 19 healthy subjects. Influenza virus-specific antibody-secreting cells (ASC) could be detected as early as 2 days after vaccination in peripheral blood and tonsils, with a peak at approximately 1 week after vaccination and a decline to insignificant levels after 6 weeks. Circulating ASC produced IgG, IgA, and IgM, whereas ASC in tonsils produced mainly IgA and IgM. Influenza virus-specific antibodies were predominantly IgG and IgM in serum and IgA in oral fluid; they rose after 1 week and were elevated at 6 weeks. This may indicate a secretory involvement of the anti-influenza virus response in the upper respiratory tract. Parenteral influenza vaccination induced an immediate and significant immune response in both the upper respiratory tract and peripheral blood.

Characterization of T cell receptor repertoire and anti-Ro/SSA autoantibodies in relation to sialadenitis of NOD mice

Non-obese diabetic (NOD) mice develop sialadenitis which morphologically resembles the exocrinopathy in human Sjögren's syndrome (SS). The sialadenitis is characterized by focal infiltrates of inflammatory cells. Immunoenzyme staining (ABC-technique) and monoclonal antibodies defining CD4, CD8, CD11b, TCR alpha/beta, gamma/delta, V beta 2, V beta 4, V beta 6, V beta 7, V beta 8.1, 2, V beta 10b and V beta 11 were used to examine the infiltrating mononuclear cells (MNC) in salivary glands of NOD mice. TCR alpha beta + cells dominated clearly over TCR gamma delta + cells in the salivary glands. A predominance of CD4+ T-cells was identified, while a small population of CD8+ cells was found in the salivary gland infiltrates. CD11b+ mononuclear cells were sporadically seen within the salivary gland lesions. All different TCR V beta:s which were analysed appeared to be utilized at the site of MNC infiltration in salivary glands; although with various frequencies. The frequency pattern of V beta gene expression in salivary glands was V beta 8.1,2 (15%) > V beta 6 (12%) > V beta 4 (11%) > V beta 10b (5%) > V beta 11 (5%) = V beta 2 (5%) > V beta 7 (3%). Analysis of the TCR V beta utilization in corresponding lymph nodes revealed a quite similar frequency pattern as found in the salivary glands. Serum samples were also tested for anti-Ro52, Ro60 and anti-La antibodies with Western blot. Autoantibody production was limited to anti-Ro/SSA and 3/37 (8%) of the mice were found to produce anti-Ro52 kD antibodies. The degree of sialadenitis (focus score) appeared not to influence reactivity to the Ro52 kD protein.

Effects of human calprotectin (L1) on in vitro immunoglobulin synthesis

Calprotectin (L1) is a major cytoplasmic protein of neutrophilic granulocytes and monocytes/macrophages which is released from leucocytes during activation or cell death. Apart from in vitro antimicrobial and antiproliferative activity little is known about the biological function of the protein. Since previous investigations have shown that calprotectin plasma levels are elevated in various inflammatory rheumatic diseases, we wanted to investigate if calprotectin has an effect on immune cell functions. Peripheral blood mononuclear cells, either unstimulated or polyclonally stimulated with mitogen, were incubated with calprotectin and effects were assessed by enumeration of immunoglobulin secreting cells (ELISPOT). The results indicate that incubation with high concentrations of calprotectin (> 64 micrograms/ml) inhibit the production of the three classes of immunoglobulins investigated (IgG, IgM and IgA), both for mitogen stimulated and unstimulated lymphocytes. Except for the highest concentration of calprotectin (500 micrograms/ml), it seems plausible that the observed inhibitory effect of calprotectin on Ig production is not a result of a direct toxic effect of calprotection on B lymphocytes. Altogether, these effects of high calprotectin levels might be of importance in the immunoregulation of inflammatory conditions.

Analysis of T-cell receptor expressing lymphocytes infiltrating squamous cell carcinomas of the upper aerodigestive tract

T-lymphocytes expressing T-cell receptors (TCRs) of the gamma/delta type have been suggested to play an important role in mucosal defense against infection and neoplastic transformation. In this study, an immunohistochemical investigation was performed on the distribution of alpha/beta and gamma/delta TCRs among tumor-infiltrating lymphocytes. Thirteen patients with squamous cell carcinomas of the upper aerodigestive tract were studied, using monoclonal antibodies and an avidin-biotin-peroxidase technique. Most of the T-cells had an alpha/beta TCR. Only 1.6% of the T-cells within the cancer tissue and 1.2% of the T-cells in the parenchyma adjacent to the cancer tissue expressed gamma/delta TCRs. These results are consistent with the results of similar studies in bronchial and breast carcinomas. Biopsies from normal oral mucosa in nine healthy individuals showed that 1.3% of the T-cells within the epithelium and 1.0% of those in the lamina propria adjacent to the epithelium expressed gamma/delta TCRs. Quantitatively the results do not support the theory that gamma/delta T-cells play an important role in the immunological response against cancer tissue in the mucosa of the upper aerodigestive tract. The functional role of these cells in the mucosa and in response to carcinomas is, however, still uncertain.

Use of a sicca symptoms questionnaire for the identification of patients with Sjögren's syndrome in a heterogeneous hospital population with various rheumatic diseases

OBJECTIVE

A six-item questionnaire regarding sicca symptoms recently validated for primary Sjögren's syndrome (SS) was tested on 154 in-patients with a wide range of inflammatory rheumatic diseases. Patients with one or more positive responses underwent objective ocular and oral diagnostic procedures. Of 27 patients thus investigated, 19 could be classified as having SS.

RESULTS

The positive answers obtained were mainly in response to 4 of the 6 questions: dry eyes, sensation of sand or gravel in the eyes, dry mouth, and drinking of liquids to aid in swallowing dry foods. Among the 19 patients found with SS, most had had earlier diagnoses of various connective tissue diseases (rheumatoid arthritis included) and most were female.

CONCLUSION

In conclusion, this study indicates that the sicca symptom questionnaire may be useful when deciding which patients with inflammatory rheumatic diseases should be subjected to special investigations with regard to SS.

Some microbiological, histopathological and immunohistochemical characteristics of progressive periodontal disease

The aim of the present investigation was to study the local nature of human periodontal disease by assessing the microbiota and the composition of the tissue lesions at sites with progressive attachment loss in periodontitis susceptible subjects. 300 subjects with periodontal disease were monitored for 2 years without treatment. 8 subjects lost > 2 mm of attachment at > or = 3 sites during both the first and the second 12 month interval. These 8 subjects (progressive disease group; PD) were recalled for a microbiological and histopathological examination. A group of age- and sex-matched subjects were identified who during the 2 years of monitoring exhibited gingivitis and deep pockets, but no further attachment loss. This group of 11 subjects (non-progressive disease group; NPD) served as controls. From the 8 active disease subjects, > or = 1 interproximal site which had displayed disease activity (progressive disease active; PDA) and > or = 1 contralateral site without disease progression (progressive disease inactive; PDI) were sampled. From the 11 control subjects, 1 site/subject was sampled (NPD). The total number of viable micro-organisms (TVC) in the subgingival microbiota was estimated and a series of bacterial species were identified and enumerated. The gingival tissue of the sampling site was excised and the soft tissue prepared for morphometrical and immunohistochemical analyses. No differences were observed in the subgingival microbiota of the sample sites in the subjects who exhibited disease progression (PD) when compared with the subjects with periodontally diseased but stable conditions (NPD).(ABSTRACT TRUNCATED AT 250 WORDS)

MRL/lpr mice produce anti-Ro 52,000 MW antibodies: detection, analysis of specificity and site of production

MRL/lpr mice are studied as one of the animal models of the human autoimmune disease Sjögren's syndrome. The mice develop inflammatory exocrinopathy resembling that of patients with Sjögren's syndrome. To investigate if MRL/lpr mice produce the anti-Ro/SS-A and anti-La/SS-B autoantibodies common to Sjögren's syndrome patients, mouse sera were tested in ELISA and Western blot with recombinant Ro 60,000 MW, Ro 52,000 MW and La antigen. Thirty per cent of mice aged 4 months and 5% of mice aged 2 months produced antibodies to human Ro 52,000 MW. Antibodies to Ro 60,000 MW and La were found in a low percentage of the older mice but not at all in the younger mice. Immunohistological staining of mouse organ sections demonstrated anti-Ro 52,000 MW-producing cells in spleen, lymph nodes and salivary glands of seropositive animals. These findings provide further evidence for the usefulness of the MRL/lpr mouse as a model for Sjögren's syndrome.

Oligoclonality of T cells in salivary glands of autoimmune MRL/lpr mice

The aim of this study was to obtain further information about exocrine glandular immunopathology and the potential of the MRL/lpr strain as a model of Sjögren's syndrome. Immunoenzyme staining (ABC technique) and monoclonal antibodies defining CD3 T-cell receptor (TcR) alpha beta, gamma delta and TcR V beta 2, V beta 4, V beta 6, V beta 7, V beta 8.1,2, V beta 10b and V beta 11 were used to identify the mononuclear cells (MNC) in salivary gland infiltrates and lymph nodes of 2- and 4-5-month-old female MRL/lpr mice. TcR alpha beta + cells dominated clearly over TcR gamma delta + cells in both salivary glands and lymph nodes. In addition, to be expressed on lymphocyte-like cells, TcR gamma delta + cells also had a dendritic appearance. The frequency pattern of TcR expression in early inflammation (2 months) was V beta 8.1, 2 > V beta 6 > V beta 4 > V beta 10b > V beta 2 > V beta 7 > V beta 11. Clear differences in frequencies could be found between salivary glands and lymph nodes in established sialadenitis (4-5 months). Particularly V beta 4, V beta 8.1,2 and V beta 10b showed expansion in salivary glands at > or = 4 months. In conclusion, this study shows a diverse repertoire of TcR at local sites of MNC infiltration in autoimmune MRL/lpr mice. However, with increasing age it also shows a preferential utilization of certain V beta gene products.

Measurement of plasma calprotectin as an indicator of arthritis and disease activity in patients with inflammatory rheumatic diseases

OBJECTIVE

To investigate if the plasma level of the granulocyte protein calprotectin is a useful indicator of severity of arthritis in patients with inflammatory rheumatic diseases, and to analyze which factors contribute to the raised plasma calprotectin levels.

METHODS

Plasma calprotectin levels were measured by ELISA: In a cross sectional study of 154 patients with various inflammatory rheumatic diseases, calprotectin levels were correlated with laboratory and clinical variables.

RESULTS

The plasma levels of calprotectin and C-reactive protein (CRP) correlated significantly with the clinical evaluation of swollen joints (r = 0.51, p < or = 0.01 and r = 0.29, p < or = 0.01, respectively). Calprotectin levels, but not CRP levels or erythrocyte sedimentation rate, were significantly lower in patients with no swollen joints than in patients with one or more swollen joints (2613.6 micrograms/l vs 6287.0 micrograms/l, p < 0.001). A significant correlation between calprotectin and number of neutrophils was demonstrated (r = 0.43, p < or = 0.01), indicating that circulating neutrophils contribute to plasma calprotectin levels.

CONCLUSION

The plasma calprotectin level may be a useful indicator of arthritis in inflammatory rheumatic diseases.

Sjögren's syndrome in inflammatory rheumatic diseases: analysis of the leukocyte protein calprotectin in plasma and saliva

In a hospital population of 154 patients with a wide range of inflammatory rheumatic diseases, patients with sicca symptoms were subjected to objective ocular and oral tests to establish cases with Sjögren's syndrome (SS). The plasma level of the leukocyte protein calprotectin has been shown to be a good indicator of disease activity and inflammation in various rheumatic diseases. In the present study, calprotectin levels in plasma and whole saliva were analysed and evaluated as potential markers of SS and salivary gland disease activity. Plasma calprotectin levels did not differ significantly between patients with SS and patients with no sicca symptoms. However, salivary calprotectin levels correlated significantly with the plasma calprotectin levels and with several ocular variables, weakly with salivary flow and serum rheumatoid factor, but not with focal sialadenitis. In conclusion, this study shows that salivary calprotectin levels seem to be associated with several variables of SS glandular pathology, indicating the need for further and more comprehensive studies on calprotectin in various oral fluids and in lacrimal fluid in relation to SS glandular disease activity.

Progression of sialadenitis in Sjögren's syndrome

An analysis of progression of sialadenitis in patients with primary and secondary SS has been performed. For this purpose patients were prospectively followed and evaluated with respect to stimulated whole salivary secretion and morphology of labial salivary gland biopsies. Twenty-one patients with primary SS and 18 with secondary SS were followed for a mean of 39 +/- 20 months (range 11-112 months). During this observation period the lymphocytic infiltration in minor salivary glands, measured as focus score, increased in 14/21 (67%) patients with primary SS and in 14/18 (78%) patients with secondary SS. Altogether there was a statistically significant increase in focus score in both primary and secondary SS, but no reduction in salivary production. Consequently, no correlation between changes in focus score and stimulated salivary secretion was found in either primary or secondary SS.

Rapid quality evaluation of hybridomas using ELISPOT and cell-ELISA techniques

We have used the ELISPOT assay in combination with ELISA procedures for rapid evaluation of properties of three different murine hybridoma cell lines, 104-I, -B and -G, secreting IgG1 kappa monoclonal antibodies against a 104-mer synthetic peptide from the C-terminal part of HIV-1 p24. By conventional ELISA we obtained data suggesting that the three monoclonal antibodies had different affinities. By cell-ELISA we found that the IgG1 kappa secretion rate varied between cells (4,000 to 14,000 antibody molecules/cell/min), and ELISPOT showed that only 4-5% of 104-I cells gave antigen-specific spots, indicating a cell population with diverse properties. We recommend that the ELISPOT and cell-ELISA techniques should be used routinely to supplement conventional ELISA procedures for rapid evaluation of hybridoma properties.

Estrogen accelerates immune complex glomerulonephritis but ameliorates T cell-mediated vasculitis and sialadenitis in autoimmune MRL lpr/lpr mice

Estrogen is known to influence immune responses in healthy subjects in a dichotomous fashion. Thus, in number of previous studies we and others have demonstrated that B cell activities are augmented after exposure to estrogen whereas T cell reactivity is suppressed. Furthermore, it has been shown that this hormone has significant impact on the course of certain human and experimental autoimmune diseases. In this study we report that treatment with physiological doses of estradiol exerts dichotomous effects on different manifestations of the lupus disease in MRL/l mice. On one hand immune complex-mediated glomerulonephritis was significantly accelerated. This outcome was due to polyclonal B cell activation with increased production of antibodies to double-stranded DNA and formation of circulating immune complexes. In contrast, T cell-mediated lesions such as focal sialadenitis, renal vasculitis, and periarticular inflammation were all significantly ameliorated in MRL/l mice exposed to estrogen. Thus, we were able to demonstrate that, within one subject and even within one organ, administration of estrogen leads to differential outcome of SLE morbidity. We propose that the differential effect of estrogen on the manifestations of the autoimmune disease of MRL/l mice is due to its dichotomous effects on B and T cell-mediated immune responses.

Genetic, hormonal and behavioural influence on spontaneously developing arthritis in normal mice

DBA/1 male mice develop arthritis spontaneously at the age of 4 months. The affected joints show cell-rich pannus formation without T cell infiltration and only limited MHC class II expression. Specific pathogen-free DBA/1 mice from different sources developed the same disease. Analyses of inbred mouse strains with various genetic backgrounds and F1 hybrids revealed that the disease is genetically dependent of DBA/1 recessive genes. However, F1 hybrids between DBA/1 and BXSB spontaneously developed arthritis with earlier onset than DBA/1 mice, suggesting that the BXSB autoimmune gene background had both permissive and contributing effects on the development of arthritis. The complete male preponderance for disease susceptibility was investigated by castration and testosterone treatment of DBA/1 males. No arthritis developed after castration and disease susceptibility was restored by testosterone treatment. Arthritis developed only where more than two males were kept in cages, suggesting an influence by aggressive behaviour. Thus, the spontaneous development of arthritis is dependent on hormonal and behavioural mediated effects and differs from experimental models for rheumatoid arthritis such as type II collagen-induced arthritis and pristane-induced arthritis. We conclude that the spontaneously developing arthritis in the normal DBA/1 strain may be more useful as a disease model for osteoarthritis than for rheumatoid arthritis.

Arthritis induced in rats with adjuvant oil is a genetically restricted, alpha beta T-cell dependent autoimmune disease

Adjuvant arthritis in rats is usually induced by injection of mycobacterium tubercle cell walls suspended in various adjuvant oils such as Freund's incomplete adjuvant (FIA) or pristane. We have recently shown that injection of adjuvant oils without inclusion of mycobacterium tubercle cell walls triggers arthritis [oil adjuvant-induced arthritis (OIA)] in the DA rat strain. The OIA is a genetically restricted disease since only DA rats are susceptible while Lewis, DA-fostered Lewis and F1 (Lew x DA) rats are relatively resistant. Activated alpha beta T cells infiltrate the affected joints of adjuvant oil-injected DA rats and treatment with monoclonal antibodies to the alpha beta T-cell receptor abrogates development of arthritis. These findings show that alpha beta T-cell activation is a critical event in the development of OIA.

Differential effects of oestrogen in murine lupus: acceleration of glomerulonephritis and amelioration of T cell-mediated lesions

Oestrogen is known to accelerate glomerulonephritis and autoantibody production in human and murine systemic lupus erythematosus (SLE). In this study we demonstrate that treatment of castrated autoimmune MRL +/+ mice with physiological doses of oestrogen results in enhanced immunoglobulin and autoantibody production as well as increased deposition of IgG in renal glomeruli. Accelerated development of glomerulonephritis was also evident from the increase of albuminuria. Interestingly, in contrast to these deteriorative effects of oestrogen on immune complex-mediated disease we now show that the lymphocytic infiltrations in the submandibular glands and perivascular lesions in the kidneys were significantly diminished after exposure to oestrogen. This remarkable impact of physiological oestrogen levels on the outcome of SLE in MRL +/+ mice is postulated to be the result of a differential effect on T and B cell-mediated immune responses.

Murine models for systemic lupus erythematosus and Sjögren's syndrome

Of the types of defects that have been observed in autoimmune mice, two are common to most strains and appear to be of critical importance in the development of autoimmune disease. The first of these is a deficiency in the maintenance of self-tolerance by B or T lymphocytes. This is an intrinsic defect due to genetic abnormalities that presumably affect an early developmental signaling mechanism. The disruption of early B- and T-cell development leads to the appearance of lymphocytes that are predisposed to loss of tolerance. In certain strains of autoimmune mice, it also leads to overproduction of Ly1+ (CD5+) B cells or CD4-CD8-B220+ T cells, which apparently do not contribute to autoimmunity. The second type of defect is a strain-specific, antigen-driven autoimmune disease syndrome. This defect is limited by the affinities of the available T-cell receptor and immunoglobulin variable regions and the efficiency of antigen presentation. Current evidence suggests that the major histocompatibility complex molecules play the most important role in determining which autoantigens lead to a pathogenic antigen-driven immune response. For example, the type and magnitude of the autoimmune response may be directed by the production of specific cytokines. The type of antigen and the context of its presentation can bias the production of cytokines that favor the production of the Th2 subset of CD4+ T helper cells. These cells secrete predominantly interleukin-4, interleukin-5, and interleukin-10, and may contribute to a chronic response and autoimmune disease.

Immunoglobulin isotype distribution of locally produced autoantibodies to collagen type I in adult periodontitis. Relationship to periodontal treatment

Production of antibodies to collagen type I was analyzed by means of an enzyme-linked immunospot (ELISPOT) assay in patients with chronic adult periodontitis (AP) before and after periodontal hygiene treatment. Anti-collagen type I antibody-secreting cells were found among mononuclear cells enzymatically eluted from inflamed gingiva in 9 of 15 patients with untreated AP and in 4 of 14 hygiene-treated patients with a varied isotype distribution. A notably high prevalence of IgG and IgM isotypes was observed for the anti-collagen antibodies in untreated patients. With wide variation, chronic AP was characterized by a high frequency of spontaneous IgG and low numbers of IgA and IgM-producing cells. Periodontal hygiene treatment significantly reduced the number of IgA and IgM-secreting cells. Although AP is not an autoimmune disease in the accepted sense, our results indicate that local autoimmune reactions to collagen type I are common in untreated AP, implying an interplay between periodontal infection and autoimmunity.

Local IgA and IgM rheumatoid factor production in autoimmune MRL/lpr mice

Spontaneous local immunoglobulin (IgA, IgG, IgM) as well as IgA and IgM rheumatoid factor (RF) production in salivary glands, lymph nodes, and spleen was analyzed at various ages in autoimmune MRL/Mp-lpr/lpr (MRL/lpr) mice by using an ELISPOT assay. The longitudinal design of the study permitted correlations with severity of disease in salivary glands (sialadenitis). Local production of immunoglobulins in salivary glands and lymph nodes occurred with a pattern of IgG much greater than IgM greater than IgA. This isotype pattern differed from that simultaneously observed in spleen where IgG did not predominate to the same extent. Moreover, the spleen was the major site of IgM production. Rheumatoid factors constituted a significant fraction of local IgA and IgM in involved salivary glands. The pattern of IgA RF isotype expression in salivary glands contrasted with that observed in spleen. While the number of IgA and IgG secreting cells increase at an early age, the peak of RF production in salivary glands occurs in older mice. Furthermore, the level of immunoglobulin secretion was positively correlated with disease severity in salivary glands. The results suggest that local RF production is a secondary event in salivary gland inflammation in MRL/1pr mice rather than an initiating factor in this process.

Swallowing problems in rheumatoid arthritis

Twenty-nine female patients with definite or classical rheumatoid arthritis (RA) and 30 controls were investigated in order to evaluate oral symptoms, particularly xerostomia, and swallowing difficulties in RA by means of a questionnaire, physical examination, stimulated saliva secretion, labial salivary gland biopsy, esophageal manometry and laboratory blood tests. Xerostomia was reported by 6 patients (21%), compared with no-one in the control group. Four of these 6 patients had decreased stimulated saliva secretion, compared with 2 of the remaining 23 patients. Dysphagia was experienced by 8 patients (28%), compared with one control subject. Dysphagia was associated with disease severity. Esophageal manometry revealed a decrease of the amplitude of the peristaltic pressure complex in the proximal part of esophagus in the RA group, indicating dysfunction of the striated muscles. No correlation was found between dysphagia and esophageal manometry results.

Multiple epitopes on cartilage type II collagen are accessible for antibody binding in vivo

Monoclonal mouse antibodies specific for the major epitopes on mouse type II collagen (CII) were biotinylated and injected into neonatal and adult mice. Anti-CII antibodies, specific for four different epitopes on the CII molecule, could be shown to bind specifically to joint surfaces in the paws of 2-day-old syngeneic DBA/1 mice after an intraperitoneal injection of 100 micrograms of biotinylated antibody. The anti-CII antibodies did not bind to cartilage from DBA/1 mice in vitro, unless the sections were pretreated with hyaluronidase or the specimens decalcified prior to freezing, showing that the epitopes are accessible in vivo but not in vitro. By analyzing the in vivo binding capacity for a number of monoclonal anti-CII antibodies which represented different IgG subclasses, it could be demonstrated that binding to the same epitopes occurred independent of IgG subclass. However, one epitope (denoted "B1") was only weakly detected, possibly due to the fact that the antibody used (CIIB1) crossreacts with type I collagen and C1q. Monoclonal anti-CII antibodies, injected into neonates or adult mice, bound specifically to most, but not all, tissues containing CII; including hyaline joint cartilage, fibrous sternal and costal cartilage, tracheal cartilage and fibrous cartilage in the spine but not to CII-containing structures in the eye. The finding that CII, while present in cartilage, is accessible for antibody binding in vivo may have important implications for the availability of CII for the immune system and for the understanding of the development of pathological autoimmunity leading to collagen-induced arthritis in mice.

Involvement of macrophages and dendritic cells in synovial inflammation of collagen induced arthritis in DBA/1 mice and spontaneous arthritis in MRL/lpr mice

Type II collagen induced arthritis (C1A) is an antigen-specific and T-cell dependent autoimmune disease in which the time course of disease is known. Arthritis is induced with type II collagen (CII) immunization, but can also be induced with passive transfer of anti-CII antibody containing syngenic serum and with local administration of gamma interferon. In the present study we analysed the spectrum of inflammatory cells appearing in the arthritic joints. Three phases of the disease process could be defined: 1) Early infiltration of T cells and appearance of class II expressing macrophages in the synovial lining layer 2) Profound infiltration of granulocytes and oedema formation and 3) Pannus formation containing activated macrophages, granulocytes, T cells and dendritic cells. At this severe destruction of cartilage and bone beginning from the marginal zone was seen. In contrast, joints from spontaneously arising arthritis in MRL lpr/lpr mice showed no granulocytes or T cells, sparse expression of class II but relatively uniform appearance of C3bi-receptor+, Fc-receptor+ and MOMA2+ synovial cells.

Elucidating the pathogenesis of autoimmune disease: recent advances at the molecular level and relevance to oral mucosal disease

Humoral and/or cellular immune responses directed against self antigen are currently thought to underlie a wide spectrum of systemic and organ-specific human and animal autoimmune diseases. Although the immunopathology of these diseases has been well characterized in most cases, the etiology still remains obscure. In order to gain a more fundamental insight of the abnormal processes leading to autoimmunity, efforts are currently being directed toward defining these diseases at a molecular level. Because of the clinical diversity and immunological complexity of these diseases, several directions are being pursued. Relevant to autoimmune oral disease, this review will focus on antigen processing and recognition (immunoglobulin and T cell receptor genes), the key role of the major histocompatibility complex, and the involvement of the cytokine network. Advances made in these fields have clear relevance for future diagnostic and therapeutic strategies related to autoimmune diseases affecting oral tissues.

Infiltrating mononuclear cells in salivary glands and kidneys in autoimmune MRL/Mp-lpr/lpr mice express IL-2 receptor and produce interferon-gamma

The salivary gland inflammatory lesions and renal vasculitic lesions of autoimmune MRL/lpr mice were analyzed for the presence of activated lymphocytes. Immunohistologic analysis revealed that the majority of lymphocyte-like cells in salivary glands and kidneys expressed CD4 antigen (greater than 50%). Lesser numbers of interleukin-2 receptor (IL-2R) expressing and interferon-gamma (IFN-gamma)-producing cells were present (1-5%). CD4+, IL-2R+, and IFN-gamma + mononuclear cells were found in small inflammatory foci. In larger inflammatory foci the IFN-gamma-producing cells were detected in the periphery in comparable numbers as the IL-2R expressing cells although with different location. Large numbers of cells in the inflammatory foci also expressed MHC Class II molecules (greater than 50%). The expression of IL-2R and production of IFN-gamma in the tissue lesions indicate presence of activated inflammatory T cells. Production of IFN-gamma by the infiltrating mononuclear cells may induce Class II antigens on epithelial cells and stimulate further T cell migration into the inflammatory site.

Expression of heterozygous lpr gene in MRL mice. II. Acceleration of glomerulonephritis, sialadenitis, and autoantibody production

Recently we showed that not only homozygous MRL lpr/lpr mice but also heterozygous MRL +/lpr mice display defective antigen- and mitogen-driven T-cell responses as well as polyclonal B-cell activation compared with congeneic MRL +/+ mice. In this study we examined the impact of the heterozygous lpr gene on organ pathology in kidneys, joints, and salivary glands, as well as serum levels of immunoglobulins and autoantibodies in young and old MRL mice. Only 1 out of 17 heterozygous lpr-bearing MRL mice developed clinically overt renal disease with significant proteinuria and haematuria during the first year of life. However, examination of Ig and C3 deposits in glomeruli of kidneys from these mice revealed that the expression of the heterozygous lpr gene in MRL mice accelerates glomerulonephritis. In addition, histological examination of the submandibular salivary glands showed an increased focus score in heterozygous MRL mice at 4-5 months of age compared with that of matched congeneic +/+ mice. In contrast, no signs of arthropathy were registered in the heterozygous lpr-bearing MRL mice. Heterozygous MRL mice displayed an expanding lymphoid system as evaluated by significantly increased spleen and lymph node weights compared with those of matched MRL +/+ mice. Further evidence for immunomodulatory properties of the heterozygous lpr gene was obtained when analysing serum levels of IgG, IgM, and autoantibodies. Thus, heterozygous MRL +/lpr mice produced significantly higher levels of both Ig and autoantibodies than matched MRL +/+ mice. We conclude that the expression of the heterozygous lpr gene in MRL mice results in acceleration of the autoimmune process, giving rise to precocious clinical disease.

Arthritis in DBA/1 mice induced with passively transferred type II collagen immune serum. Immunohistopathology and serum levels of anti-type II collagen auto-antibodies

Arthritis was induced in DBA/1 mice by passive transfer of syngeneic anti-type II collagen (CII) serum concentrate. After transfer of serum containing 0.2 or 0.5 mg anti-CII auto-antibodies the first clinical signs of arthritis appeared 48 h after injection. Severe clinical arthritis was detected 96 h after injection. Immunohistochemical analyses of joints 48 h after serum injection revealed synovial foci in intercarpal and metacarpophalangeal joints of macrophage-like cells, expressing C3bi-receptors and major histocompatibility complex class II molecules, and infiltration of few CD4+ lymphocytes. Later (96 h after injection), the inflamed synovia were dominated by C3bi-receptor+ polymorphonuclear cells. In contrast to conventionally induced collagen arthritis (CIA), the inflammatory infiltrates, filling joint spaces and synovial tissue, were extensively dominated by polymorphonuclear cells, whereas macrophage-like cells expressing class II molecules and a few T cells were seen only in the periphery of the developing pannus. The anti-CII serum induced arthritis may be used as a model for studies of humoral mediated mechanisms operating in conventionally induced CIA as well as in rheumatoid arthritis.

The relationship between intraoperatively assessed atrial and ventricular insertions of accessory pathways

To gain insight into the complex problems regarding the extension of the atrial and ventricular insertions of anomalous pathways, the activation patterns obtained from intraoperative epicardial mapping in 23 patients with Wolff-Parkinson-White syndrome were carefully analyzed. The atrial and ventricular activation times along the atrioventricular groove were measured at 15 predefined anatomical landmarks. The width of the region of earliest atrial and ventricular activation times and the extent of atrial and ventricular overlap were assessed. The relationship between the atrial and ventricular insertions was studied by predicting the ventricular insertions from the observed atrial insertions and vice versa. The mean extension of an atrial and a ventricular insertion at surgery was 1.9 +/- 0.2 (SE) and 1.6 +/- 0.2 (SE) anatomical landmarks, respectively. The width of the region of early atrial and ventricular activation times measured 2.7 +/- 0.3 (SE) landmarks, thus indicating an overlap of the atrial and ventricular insertions. The lateral distance between the sites of earliest atrial and ventricular activation times was, on average, 1.7 +/- 0.3 (SE) landmarks. The predicted atrial insertion from a known ventricular insertion, and vice versa was found to cover 4 to 6 anatomical landmarks. These observations suggest that wide surgical dissections along the atrioventricular groove are warranted even if epicardial mapping discloses only a single accessory pathway.

Non-stereo photographic screening after panretinal photocoagulation for proliferative diabetic retinopathy. Compared with 60D enhanced slit-lamp examination

135 patients treated with panretinal photocoagulation for proliferative diabetic retinopathy were examined in order to detect 7 specific fibrovascular lesions after treatment. Two presumptive methods for long-term follow-up were evaluated and compared, i.e. slit-lamp biomicroscopy enhanced by a 60 D lens and reading from two non-stereo photographs of the posterior pole. Two observers repeated their examinations with respective methods. Comparison of the methods with respect to detecting ability of the fibrovascular lesions showed no significant disagreement except in some eyes with fibrous tissue on the optic disc where new vessels were better detected with the slit-lamp method (P less than 0.001). There was no difference between the methods with respect to the intra- and inter-observer variability. Twenty to 30 patients could be diagnosed per hour with the photographic method compared to 5-6 patients with the slit-lamp. Two non-stereo photographs of the posterior pole can be recommended as a safe and time-saving method for objective documentation and long-time follow-up after panretinal photocoagulation for proliferative diabetic retinopathy.

Phenotypic characterization of mononuclear cells and class II antigen expression in angular cheilitis infected by Candida albicans or Staphylococcus aureus

In the present study we characterized the phenotypes of infiltrating mononuclear cells in angular cheilitis lesions to further explore the pathogenesis of this disorder. Frozen sections from lesions infected by Candida albicans and/or Staphylococcus aureus were subjected to immunohistochemical analysis utilizing monoclonal antibodies directed to subsets of T-lymphocytes, B-lymphocytes, and macrophages. In addition, the expression of Class II antigens (HLA-DP, -DQ, -DR), the interleukin 2- and transferrin-receptors was studied on resident and infiltrating cells. An intense infiltration of T-lymphocytes was accompanied by expression of Class II antigens on the epidermal keratinocytes in lesion infected by Candida albicans. The Staphylococcus aureus infected lesions displayed a diffuse infiltration of T-lymphocytes but virtually no expression of Class II antigen by epidermal keratinocytes. These observations suggest that the cell-mediated arm of the immune system is involved in the inflammatory reaction of lesions infected by Candida albicans. In addition, the present study confirms that epidermal expression of Class II antigens is closely related to the type and magnitude of the infiltrating T-lymphocyte. Finally, these findings indicate that the type of inflammatory reaction in angular cheilitis is primarily dependent on the isolated microorganism, although the clinical pictures of the disorder are virtually identical.

Demonstration of immunoreactive sites on cartilage after in vivo administration of biotinylated anti-type II collagen antibodies

Administration of biotinylated monoclonal antibodies provides the basis of a simple technique for identifying immunoreactive sites in vivo. Biotinylated anti-type II collagen antibodies were injected intraperitoneally into normal DBA/1 mice. The mice were sacrificed after 96 hr and the front paws removed and decalcified to allow tissue sectioning before snap-freezing. Binding of antibodies in vivo was visualized with affinity cytochemical staining using avidin-biotin-peroxidase complexes. Specific binding of antibodies to cartilaginous structures was seen after injection of 20-500 micrograms biotinylated monoclonal or polyclonal anti-type II collagen antibodies, but not after injection of a biotinylated control antibody. This technique should further the detection and localization studies of tissue components involved in the dynamics of physiological and pathological processes.

Ventricular dimensions and wall motion assessed by echocardiography in patients with arrhythmogenic right ventricular dysplasia

Twenty patients with arrhythmogenic right ventricular dysplasia (ARVD) and 20 healthy volunteers underwent cross-sectional echocardiographic examination for the assessment of ventricular dimensions and wall motion. Right ventricular cavity diameters and wall segments were selected from the inflow and outflow tracts and the right ventricular body. The measurement error for measuring cavity dimensions was low throughout and the reproducibility of wall motion scoring was high in both the normal subjects and the patients. All except one patient had increased dimensions and/or abnormal wall motion in the right ventricle. The right ventricular inflow tract was dilated in nine patients, the outflow tract in 11 patients and the short- or long-axis diameters of the right ventricular body were increased in seven patients. Right ventricular wall motion abnormalities, being the most frequent finding, ranged from mild hypokinesia only to dyskinesia or sacculations, and were fairly evenly distributed among the segments studied. Left ventricular abnormalities, found in eight patients, were generally mild. Cross-sectional echocardiography thus provides highly reproducible measurements of right ventricular size and contraction patterns even in patients with wall shape deformities, and is therefore a feasible non-invasive method for the evaluation of right-sided myocardial abnormalities in patients with ARVD. The diagnostic accuracy of this technique warrants further clarification.