Immunofluorescent studies on circulating lymphocytes in oral mucosal diseases

Mucosal disease series. Number VI. Recurrent aphthous stomatitis

Recurrent aphthous stomatitis (RAS; aphthae; canker sores) is a common condition which is characterized by multiple recurrent small, round or ovoid ulcers with circumscribed margins, erythematous haloes, and yellow or grey floors typically presenting first in childhood or adolescence. RAS occurs worldwide although it appears most common in the developed world. The aetiology of RAS is not entirely clear. Despite many studies trying to identify a causal microorganism, RAS does not appear to be infectious. A genetic predisposition is present, as shown by strong associations with genotypes of IL-1beta; IL-6 in RAS patients, and a positive family history in about one-third of patients with RAS. Haematinic deficiency is found in up to 20% of patients. Cessation of smoking may precipitate or exacerbate RAS in some cases. Ulcers similar to RAS may be seen in human immunodeficiency virus disease and some other immune defects, and drugs, especially non-steroidal anti-inflammatory drugs and nicorandil may produce lesions clinically similar to RAS. Topical corticosteroids can often control RAS. However, the treatment of RAS remains unsatisfactory, as most therapies only reduce the severity of the ulceration and do not stop recurrence.

Recurrent aphthous stomatitis

Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal disorders. Nevertheless, while the clinical characteristics of RAS are well-defined, the precise etiology and pathogenesis of RAS remain unclear. The present article provides a detailed review of the current knowledge of the etiology, pathogenesis, and management of RAS.

Are viruses associated with aphthae and oral vesiculo-erosive disorders?

Oral and maxillofacial surgeons in District General Hospitals in UK often carry the major workload of patients with chronic oral ulcerative conditions. Although the immunopathogenic basis of many of these is being unravelled, the aetiology is often unclear, though a role for viruses is increasingly suspected. This paper reviews the current evidence.

Clinical, historic, and therapeutic features of aphthous stomatitis. Literature review and open clinical trial employing steroids

The clinical and historic features of 50 patients with diagnosed aphthous stomatitis and treated with topical triamcinolone acetonide, 0.1% or 0.2% aqueous suspension; alone or in combination with initial burst therapy of 40 to 60 mg of prednisone, are reviewed. The mean age of our patients was 36.6 years (range 6 to 80 years). The duration of the chief complaint, usually oral pain, or more specifically, recurrent oral ulcers, was 11.1 years (range 4 weeks to 40 years). All patients showed a wide range of ulcer sizes when examined initially or at follow-up. Forty were followed up for an average of 22.9 months. Thirty-four reported prompt healing of ulcers identified at the time of initial evaluation, and no or markedly fewer ulcers subsequently if maintenance therapy of prophylactic topical triamcinolone, 0.1% or 0.2% aqueous rinse, was used. Five patients reported partial relief. No systemic side effects were noted even after long-term topical therapy. Local candidosis was a complication encountered in five patients.

Viruses and chronic disorders involving the human oral mucosa

Viruses have been implicated in the etiology of several chronic disorders of the oral mucosa. Most of these associations have been with DNA viruses, particularly certain herpesviruses, which are associated, for example, with some cases of erythema multiforme and with hairy leukoplakia. Papillomaviruses are associated with various papillomatous lesions, focal epithelial hyperplasia, and possibly with some carcinomas. Viruses may possibly be associated with recurrent aphthae, Behçet's syndrome, and some dermatoses. The literature concerning these possible associations is reviewed. However, much more research needs to be done before the full story of viral associations with oral mucosal disorders can be written.

Recurrent aphthous stomatitis: current concepts of etiology, pathogenesis and management

Recurrent aphthous stomatitis (RAS) is a common oral disorder, however, despite detailed clinical, immunologic, hematologic and microbiologic investigation, the etiology of RAS remains unknown. At present, topical steroids and antimicrobial mouth rinses are the mainstays of treatment, but there is still no means of preventing recurrence of the oral ulceration.

The decreased antibacterial activity of oral polymorphonuclear leukocytes coincides with the occurrence of virus-carrying oral lymphocytes and epithelial cells

Patients suffering from periodontitis or periodontosis were selected for the study. Further subdivision of these groups was based on the presence or absence of herpes and/or adenoviruses in their oral lymphocytes and epithelial cells. The phagocytic and bactericidal activities of oral leukocytes isolated from the same individuals were compared with virus carriage. In the periodontitis group, 60.5%, and in the periodontosis group 61.5% of patients carried viruses, while this was established only in 21.1% of control cases. On the other hand, emigration and sulcular gathering of the less viable polymorphonuclear leukocytes was elevated but their phagocytotic activity was decreased among periodontitis patients. Bactericidal capacity was significantly lowered among those subjects who carried viruses in their cells, as compared with virus-free persons, especially in the periodontitis group. The functions of the polymorphonuclear leukocytes accumulated in the sulcus gingivalis may be modified by mediators released from the virus-carrying cells. These mediators could achieve a greater concentration locally, and the damaged leukocytes would not be able to eliminate the microbes continuously so that the accumulation of bacterial products, among them endotoxins, could lead to periodontal inflammation.

Humoral responses and cross-reactivity to viridans streptococci in recurrent aphthous ulceration

It has been proposed that recurrent aphthous ulceration (RAU) is caused by hypersensitivity to oral streptococci. This hypothesis is based on reports that RAU patients have increased levels of circulating IgG antibodies against oral streptococci, and that rabbit antisera prepared against oral streptococci are cross-reactive with oral mucosa. Using indirect immunofluorescence, we have investigated both of these reported phenomena. End-point titers of serum antibodies against three different strains of oral streptococci were assayed from nine RAU subjects with active ulcers and compared with those of nine control subjects. Titers ranged from 1:2 to 1:64 in both groups and do not appear to have any clinical or immunopathogenic significance. Cross-reactivity was studied using hyperimmune rabbit antisera raised against five different strains of oral streptococci. Homologous bacterial titers ranged from 1:1024 to 1:8192, but none of these anti-streptococcal sera produced heterologous titers greater than 1:32 with oral mucosa. This apparent low level of cross-reactivity with oral mucosal antigens appears to be non-specific and clinically insignificant. In previous reports, we have used both leucocyte migration and lymphocyte blast transformation to study cell-mediated immunity to viridans streptococci in RAU (Gadol et al., 1985; Greenspan et al., 1985). None of our results supports an immunopathogenic role for oral streptococci in RAU.

Effects of suspected foodstuff challenging agents in the etiology of recurrent aphthous stomatitis

Two hundred eighteen professional students were surveyed to uncover any association of recurrent aphthous stomatitis (RAS) with a history of allergic diathesis. No significant relationship was uncovered. From this population approximately equal numbers of RAS-positive and RAS-negative subjects were challenged with suspected foodstuff agents thought to have a potential causative role in occurrence of the disease. The results failed to document any causative effect with regard to tomatoes, strawberries, or walnuts.

Immunological and virological investigations in Down's syndrome

Lymphocyte responsiveness to phytohaemagglutinin and viral antigens was studied in children with Down's syndrome and in controls. Mitogen-responsiveness in the patients was significantly reduced as compared to the control values. Using the lymphocyte transformation test, trisomic patients showed more than a twofold increase in sensitivity to herpes simplex virus as compared to controls. The same test did not show any essential difference between the two groups when adeno- and influenza viruses were used. Immunofluorescence technique, with specifically conjugated antiviral sera, permitted the detection of specific fluorescence in 30% of the patients with Down's syndrome indicating the presence of oncogenic adenovirus type 12 antigen in the circulating lymphocytes. No antibodies--or only very low titres--against adeno- and herpes simplex viruses were demonstrated in the sera of trisomic patients. Mononuclear leukocytes from these patients often showed structural alterations. The incidence of infectious herpes simplex virus and Candida albicans in the saliva of patients was higher than in the control group. It seems that Down's syndrome involves partial disturbance of both the cellular and humoral immune functions--at least with respect to certain viral antigens.

An immunofluorescence study on the cross-reaction between strep. 2a and human oral mucosa

Immunologic cross-reactions between Strep. 2A, fetal human oral mucosa (FHOM), and adult human oral mucosa (AHOM) were investigated by the use of a double layer immunofluorescence staining technique. Rabbit sera were prepared against Strep. 2A and FHOM. Seventeen sera from patients with recurrent aphthous stomatitis (RAS) and with known antibodies against Strep. 2A and AHOM were examined for antibodies against FHOM. The distribution of endpoint titers against FHOM in the sera from RAS differed significantly from the distribution in 17 controls. The immune absorptions in the rabbit sera and in the 17 sera from patients with RAS indicate that some cross-reacting antigenic determinants are shared between Strep. 2A, FHOM, and AHOM. Further, the present results indicate that antibodies are produced against antigenic determinants which are not shared by Strep. 2A, FHOM, and AHOM. The role of cross-reacting antigens in the pathogenesis of RAS is discussed but remains obscure.