T helper 2 and regulatory T-cell cytokine production by mast cells: a key factor in the pathogenesis of IgG4-related disease.

IgG4-related disease is a systemic disorder with unique clinicopathological features and uncertain etiological features and is frequently related to allergic disease. T helper 2 and regulatory T-cell cytokines have been reported to be upregulated in the affected tissues; thus, the production of these cytokines by T helper 2 and regulatory T cells has been suggested as an important factor in the pathogenesis of IgG4-related disease. However, it is not yet clear which cells produce these cytokines in IgG4-related disease, and some aspects of the disorder cannot be completely explained by T-cell-related processes. To address this, we analyzed paraffin-embedded sections of tissues from nine cases of IgG4-related submandibular gland disease, five cases of submandibular sialolithiasis, and six cases of normal submandibular gland in order to identify potential key players in the pathogenesis of IgG4-related disease. Real-time polymerase chain reaction analysis confirmed the significant upregulation of interleukin (IL)4, IL10, and transforming growth factor beta 1 (TGFß1) in IgG4-related disease. Interestingly, immunohistochemical studies indicated the presence of mast cells expressing these cytokines in diseased tissues. In addition, dual immunofluorescence assays identified cells that were double-positive for each cytokine and for KIT, which is expressed by mast cells. In contrast, the distribution of T cells did not correlate with cytokine distribution in affected tissues. We also found that the mast cells were strongly positive for IgE. This observation supports the hypothesis that mast cells are involved in IgG4-related disease, as mast cells are known to be closely related to allergic reactions and are activated in the presence of elevated non-specific IgE levels. In conclusion, our results indicate that mast cells produce T helper 2 and regulatory T-cell cytokines in tissues affected by IgG4-related disease and possibly have an important role in disease pathogenesis.

Soft tissue, joint, and bone manifestations of AL amyloidosis: clinical presentation, molecular features, and survival.

OBJECTIVE: To characterize symptoms and signs of AL amyloidosis that may bring patients to the attention of rheumatologists, evaluate Ig V(L) gene usage in this subgroup of patients, and assess the impact of soft tissue and bone involvement and V(L) gene usage on survival. METHODS: Clinical features of soft tissue and bone involvement were assessed in 191 patients with AL amyloidosis. V(L) gene sequencing was carried out to determine light-chain family, rate of somatic mutation, and evidence of antigen selection. The association of soft tissue and bone involvement with V(L) gene usage was assessed by logistic regression analysis, and survival time was analyzed using log rank tests and Cox regression models. RESULTS: Soft tissue and bone involvement occurred in 42.9% of the patients, and 9.4% had dominant soft tissue and bone involvement. The most common manifestations were submandibular gland enlargement, macroglossia, and carpal tunnel syndrome. Dominant soft tissue and bone involvement was significantly associated with V(L)kappaI gene usage. Mutation rate and evidence of antigen selection in the V(L) genes were not found to be confounding factors, providing evidence against a contribution of autoimmunity in this type of AL amyloidosis. Survival time was initially longer in patients with dominant soft tissue and bone involvement than in patients with other dominant organ involvement; however, this difference diminished over time. CONCLUSION: Amyloid infiltration into soft tissue, joints, periarticular structures, and bones can bring patients with AL amyloidosis to the attention of rheumatologists. Recognition of the presenting symptoms is essential for accurate diagnosis and appropriate treatment, since the long-term outlook for untreated patients with dominant soft tissue and bone involvement is not better than that for patients with other dominant features of AL amyloidosis.

Rosai Dorfman disease of the parotid and submandibular glands: salivary gland scintigraphy and oral findings in two siblings.

Rosai-Dorfman disease (RDD) is an unusual clinical entity characterized by benign pseudolymphomatous proliferation with significant histiocytic infiltration. In the present paper, extranodal RDD of the major salivary glands causing salivary hypofunction and the results of salivary gland scintigraphy and ultrasound are presented in two siblings. Case 1: a 10-year-old boy with bilateral painless masses around the parotid and submandibular glands was referred. Ultrasound examination showed bilateral, well-defined, hypoechoic solid mass lesions within both parotid glands with minimal normal parenchyma in the upper poles. Both submandibular glands were markedly hypoechoic and heterogeneous. Mass lesions within the parotid glands appeared as cold lesions with regular contours on scintigraphy. Dynamic images showed normal uptake and normal response to secretion in the upper poles of the parotid glands, corresponding with ultrasonographically normal parenchyma. Both submandibular glands showed markedly diminished uptake and secretion. Case 2: a 9-year-old boy presented with mass lesions around the submandibular glands. Ultrasound examination showed normal parotid glands and markedly hypoechoic and heterogeneous submandibular glands. Salivary gland scintigraphy showed normal uptake and secretion of parotid glands with markedly diminished uptake and secretion in both submandibular glands. There were severe carious lesions in both patients due to salivary hypofunction. Treatments of the two patients' teeth were performed. Major salivary gland involvement of RDD is important for dentists as it may cause xerostomia and can mimic dental abscess. Functional evaluation of salivary glands with scintigraphy, besides radiological and pathological techniques, will help to explain whether salivary glands are affected or not and improve the diagnostic effectiveness.

Expression of neutrophil gelatinase-associated lipocalin in human salivary glands.

OBJECTIVES: We performed an observational study of RNA and protein expression in human tissue to examine the distribution of neutrophil gelatinase-associated lipocalin (NGAL) in normal and chronic inflammatory salivary tissues, and to investigate the expression level of NGAL in inflammatory conditions of salivary glands. METHODS: Normal salivary gland tissues and tissue samples of salivary glands with chronic sialadenitis were obtained. Expression of NGAL was investigated by reverse transcriptase-polymerase chain reaction, and semiquantitative analysis of these results was also performed. The differential localization and amount of immunoreactivity to NGAL protein was evaluated by immunohistochemistry and Western blot analysis in normal salivary gland tissues and salivary glands with chronic sialadenitis. RESULTS: NGAL messenger RNA transcripts were detected in the tissues from the salivary glands with chronic sialadenitis, but only a small amount was detected in the tissues from the normal salivary glands. A weak expression of NGAL protein was occasionally seen in a few ductal epithelial cells of normal salivary gland tissue. However, in tissue samples from glands with chronic sialadenitis, the NGAL protein was expressed strongly in ductal epithelial cells and infiltrating inflammatory cells. CONCLUSIONS: These results imply that NGAL is associated with the regulation of inflammation in salivary glands.

Adenoviral-mediated gene transfer to mouse salivary glands.

Adenoviral vectors effectively transfer genes to rat salivary glands. However, potent immune responses limit their use in vivo. Mice offer more opportunities than rats for the study of these immune processes. We first established conditions for infection of mouse salivary glands, with an adenoviral vector. The effects of time, viral dose, viral diluent buffer volume, and dexamethasone on expression of a transgene, luciferase, were determined by means of the recombinant vector AdCMVluc. Optimal luciferase expression was observed when the vector was suspended in 50 microL of buffer. This volume completely filled the gland parenchyma and slightly distended the capsule. Dexamethasone increased immediate transgene expression and reduced the acute inflammation one day following viral administration, but did not alter subsequent mononuclear inflammation or transgene expression 14 or 28 days later. An adenoviral vector encoding either anti-inflammatory cytokine IL-4 or IL-10 was co-administered with AdCMVluc to increase transgene expression at 14 and 28 days. While this strategy did not extend the duration of luciferase expression, co-administration of AdCMVIL-10 with AdCMVluc almost completely eliminated the chronic inflammatory infiltrate in the glands after 28 days. This study demonstrates that adenoviral-mediated gene transfer to mouse submandibular glands is possible by intraductal cannulation and that reduction of either the acute or chronic inflammatory infiltrates was insufficient to increase long-term transgene expression in this tissue.

Expression and localization of mRNA for epidermal growth factor and epidermal growth factor receptor in human cholesteatoma.

The roles of epidermal growth factor (EGF) and epidermal growth factor receptor (EGF-R) in the proliferation and progression of the epithelium of middle ear cholesteatoma were studied. An attempt was made to elucidate the site and degree of localization of the EGF mRNA and EGF-R mRNA in the epithelium of the cholesteatoma by means of the non-radioactive in situ hybridization method. Ten cholesteatoma specimens excised during operations and six normal skin specimens (control) collected from the external ear canal were used in this study. The signal of the EGF mRNA was slightly expressed in part of the basal cells in only one of the six control specimens, while the signal was strongly expressed along the basal cells of the cholesteatoma epithelium in five of the ten specimens. The signal of the EGF-R mRNA was observed along the basal cell layer in five of the six control specimens, while the signal was strongly expressed in all layers of the cholesteatoma epithelium in all ten specimens. The expression was especially marked in the basal cell layer. These findings suggest the possibilities that abnormal expression of the EGF-R mRNA in nearly entire epithelial layers of cholesteatoma is due to overexpression of EGF-R gene, and that there is a mechanism of epithelial basal cell proliferation through an autocrine regulatory system via EGF and EGF-R.

[Immunohistochemical study of the submaxillaritis in MRL/1 mouse (lymphoproliferation and autoimmunity)].

MRL/1 mice, reported by Murphy and Roths, are lupus mice in which monogenic mutation has occurred. They are characterized by the expression of massive lymphoadenopathy, splenomegaly, arthritis and glomerulonephritis. These specific characters are attributable to the proliferation of abnormal T cells governed by an autosomal recessive gene, which is called a lymphoproliferative (lpr) gene. In this study, the author has studied the pathology of various organs in MRL/1 mice in relation to their ages. Investigated the pathogenesis of spontaneous submaxillaritis in MRL/1 mice and mechanism of its occurrence. Based on the immunological abnormalities in MRL/1 mice studied thus far, the mechanism of onset of submaxillaritis is believed to be as follows; (1) expression of the lpr gene leads to proliferation of T cells accompanied by focal lymphocyte infiltration in the submandibular gland; (2) the helper T function of these proliferating T cells induces polyclonal B cell activation (PBA); (2) PBA leads to the formation of numerous autoantibodies and anti-gp70 antibody whose antigen is the glycoprotein of endogenous retrovirus, resulting in the massive formation of immune complexes; (4) the immune complexes are deposited on the vascular wall, resulting in activation of the complement system; (5) infiltration of neutrophils and macrophages is induced; and (6) the lysosomal enzymes, released from these cells, effects as a cytotoxic mediator and damages the vascular wall. In brief, submaxillaritis accompanied by granulomatous vasculitis can be regarded as a Type III allergic response caused by immunological abnormalities which are genetically determined by the lpr gene; it is thought to be a subtype of immune complex disease.