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According to the fourth revised edition of the world health organization classification of hematopoietic tumors, methotrexate (MTX)-associated lymphoproliferative disorder (MTX-LPD), an atypical pathological condition, is categorized under other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPDs). An 80-year-old woman presented with OIIA-LPDs that simultaneously occurred in the gingiva and intestinal mucosa, causing intestinal perforation requiring emergency surgery. She was referred to our hospital because of poor wound healing after maxillary right first molar extraction. She had been prescribed MTX and prednisolone for rheumatoid arthritis and bisphosphonate for osteoporosis. We diagnosed her with medication-related osteonecrosis of the jaw, as the lesion showed bone exposure with mild redness and swelling of the surrounding gingiva and a cytological result of Class II. However, 9 months later, following the exfoliation of a partial sequestrum of the maxillary right first molar, a rapidly growing mass with gingival necrosis appeared, necessitating a biopsy. Simultaneously, abdominal pain worsened, and computed tomography revealed intestinal perforation; an emergency laparotomy was performed to remove the perforation and the surrounding ulcer-prone area. Histopathological examination of both lesions revealed diffuse large B-cell lymphomas. The final diagnosis was of MTX-LPD, as the mass, gingival necrosis, and residual small intestinal ulcer disappeared 2 months after MTX discontinuation. The exposed bone completely disappeared after 24 months, and no recurrence was noted after 60 months following MTX discontinuation. Although intestinal perforation due to MTX-LPD is extremely rare, patients with RA are immunosuppressed. Therefore, MTX-LPD must be recognized as a dangerous condition that requires careful general monitoring in such patients. [ABSTRACT FROM AUTHOR]

Other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPDs), which are uncontrolled lymphoid proliferation or lymphoma induced by immunosuppressive medication, arise mainly in patients with rheumatoid arthritis (RA). The vast majority of OIIA-LPDs are caused by methotrexate (MTX), and the reported incidence rates in the oral and maxillofacial regions are similar to those in other organs. In addition, tofacitinib (TFC), which is a Janus kinase inhibitor, has been clinically applied for the immunosuppressive treatment of RA in recent years. Herein, we present a case of OIIA-LPD of the oral floor in a patient with RA who had been treated with TFC and MTX. Clinical and pathological findings suggested that inflammatory stomatitis and/or infective response by oral bacteria promoted lymphoid activation in the oral mucosa, which could potentially become malignant. This case report indicates that OIIA-LPD might result from the combined usage of MTX and TFC, and a synergistic influence between MTX and TFC on immunosuppression may lead to diversification of OIIA-LPDs. The findings suggest the difficulty in controlling complications of RA and the importance of understanding the mechanisms of immunosuppressive treatments. [ABSTRACT FROM AUTHOR]

Recurrent or chronic oral pain is a great burden for patients. Recently, the links between epithelial barrier loss and disease were extended to include initiation and propagation. To explore the effects of pathohistological changes in oral epithelia on pain, we utilized labial mucosa samples in diagnostic labial gland biopsies from patients with suspected Sjögren's syndrome (SS), because they frequently experience pain and discomfort. In most labial mucosa samples from patients diagnosed with SS, disseminated epithelial cellular edema was prevalent as ballooning degeneration. The disrupted epithelia contained larger numbers of infiltrating macrophages in patients with oral pain than in patients without pain. Immunohistochemistry revealed that edematous areas were distinct from normal areas, with disarranged cell–cell adhesion molecules (filamentous actin, E-cadherin, β-catenin). Furthermore, edematous areas were devoid of immunostaining for transient receptor potential channel vanilloid 4 (TRPV4), a key molecule in adherens junctions. In an investigation on whether impaired TRPV4 affect cell–cell adhesion, calcium stimulation induced intimate cell–cell contacts among oral epithelial cells from wild-type mice, while intercellular spaces were apparent in cells from TRPV4-knockout mice. The present findings highlight the relationship between macrophages and epithelia in oral pain processing, and identify TRPV4-mediated cell–cell contacts as a possible target for pain treatment. [ABSTRACT FROM AUTHOR]

The article details a study which investigated if induction of systemic inflammation accelerates the development of Sjögren's syndrome (SS) in genetically susceptible mice. The study treated female mice with either Freund's incomplete adjuvant (IFA) or phosphate buffered saline (PBS). The mice were killed at different time points and underwent sialadenitis and salivary gland-infiltrating cells tests. It concluded that generalized inflammatory stimuli can accelerate the development of SS-like disease.

The mouse submandibular gland (SMG) is important organ for embryonic development, and branching morphogenesis is regulated by many molecules containing transcription factors. Real-time reverse transcriptase polymerase chain reaction revealed that the expression of Brachyury increased in the SMG and peaked between E12.5–E13.5, concomitant with the early stage of branching morphogenesis. The expression of Brachyury in SMG rudiments between E12.5–E13.5 was confirmed by western blotting. In addition, fibronectin and Btbd7 (regulated by fibronectin), which are both essential for cleft formation, were expressed strongly during the same period. The Sox2 and Wnt3a , which regulate cell growth, were also expressed strongly during E12.5–E13.5. On the other hand, cleft formation and branching morphogenesis was suppressed by knockdown of Brachyury gene, suggesting that Brachyury plays a central role in regulating cell growth and cleft formation in early-stage embryonic mouse salivary gland development. [ABSTRACT FROM AUTHOR]

Background/aim: Bone resolution due to tumor invasion often occurs on the surface of the jaw and is important for clinical prognosis. Although cytokines, such as TNF-α are known to impair osteoblasts, the underlying mechanism remains unclear. Protein myristoylation, a post-translational modification, plays an important role in the development of immune responses and cancerization of cells. A clear understanding of the mechanisms underlying this involvement will provide insights into molecular-targeted therapies. N-myristoyltransferase1 (NMT1), a specific enzyme involved in myristoylation, is expressed in cancer cells and in other normal cells, suggesting that changes in myristoylation may result from the regulation of NMT1 in cancer cells., Materials and Methods: Using newly emerging state-of-the-art techniques such as the Click-it assay, RNA interference, mass spectrometry, immunoprecipitation, immunocytochemistry, and western blotting, the expression of myristoylated proteins and the role of TNF-α stimulation on NMT1 and Sorbs2 binding were evaluated in a murine osteoblastic cell line (MC3T3-E1)., Results: The expression of myristoylated proteins was detected; however, TNF-α stimulation resulted in their inhibition in MC3T3-E1 cells. The expression of NMT1 also increased. Immunoprecipitation and mass spectrometry identified Sorbs2 as a novel binding protein of NMT1, which upon TNF-α stimulation, inhibited myristoylation., Conclusion: The binding between NMT1 and Sorbs2 can regulate myristoylation, and NMT1 can be considered as a potential target molecule for tumor invasion., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Nuclear factor kappa B (NF-kB) signalling including the RelA subunit is activated upon fibroblast growth factor (FGF) stimulation. A clear understanding of the mechanisms underlying this action will provide insights into molecular targeting therapy. Furthermore, protein phosphatase 2A (PP2A) is involved in RelA dephosphorylation, but little is known about the underlying mechanism., Materials and Methods: Because the regulatory subunits of PP2A drive NF-kB signalling via RelA, we used qRT-PCR and immunoblot analysis to investigate the expression of these subunits in MC3T3-E1 cells. We examined weather FGF2 interacts with NF-kB using immunocytochemistry (IC), immunoprecipitation (IP), and pull-down assay (PD) using recombinant proteins., Results: PR55β expression was increased, whereas activated RelA was dephosphorylated upon FGF2 stimulation. Further, the interaction of PR55β with RelA was confirmed by IC, IP, and PD., Conclusion: FGF2-induced PR55β directly interacts with RelA and regulates NF-kB signalling., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Objectives: In this study, we investigated the diagnostic utility of submandibular gland (SMG) sonography and labial salivary gland (LSG) biopsy as a less invasive procedure for diagnosing IgG4-related dacryoadenitis and sialadenitis (IgG4-DS) Methods: Sixty-eight patients with suspected IgG4-DS by presenting swelling of elevated serum IgG (>1747 mg/dl) and/or swelling glands underwent SMG sonography, LSG biopsy and measurement for serum IgG4. SMG sonographic diagnosis was determined by the following characteristic changes; 'hypoechoic areas of a nodal pattern with high vascularity' and/or 'hypoechoic areas of a reticular pattern in the superficial part'. Results: Thirty-one patients were diagnosed with IgG4-DS, 5 with IgG4-RD unaccompanied by lacrimal and salivary gland lesions, 28 with Sjögren's syndrome, and 4 with malignant lymphoma. The sensitivity, specificity, and accuracy of SMG sonography and LSG biopsy were 100%, 83.8%, 91.2% and 64.5%, 73.8%, 75.0%, respectively. Moreover, those of SMG sonography and LSG biopsy combined with serum IgG4 concentration (>135 mg/dl) were 100%, 94.6%, 97.1% and 64.5%, 91.9%, 79.4%, respectively. Conclusion: LSG biopsy needs to be extremely careful to diagnose IgG4-DS because of its low sensitivity. SMG sonography is sufficient for the diagnosis of IgG4-DS, especially when combined with serologic analysis. Thus, SMG sonography could adapt to the diagnostic criteria of IgG4-DS as a non-invasive method.

Background/aim: Adenoid cystic carcinoma (AdCC) is a rare cancer of the salivary gland with high risk of recurrence and metastasis. Wnt signalling is critical for determining tumor grade in AdCC, as it regulates invasion and migration. β-catenin dephosphorylation plays an important role in the Wnt pathway, but its underlying molecular mechanism remains unclear., Materials and Methods: Because the regulatory subunits of protein phosphatase 2A (PP2A) drive Wnt signalling via target molecules, including β-catenin, we used qRT-PCR and immunoblot analysis to investigate the expression of these subunits in an AdCC cell line (ACCS) and a more aggressive subline (ACCS-M)., Results: PR55β was highly expressed in ACCS-M, suggesting its functional importance. In addition, PR55β expression was associated with tumor grade, with ACCS-M exhibiting higher PR55β levels. More importantly, knockdown of PR55β in ACCS-M cells significantly reduced invasiveness and metastatic ability. Furthermore, dephosphorylation and total levels of β-catenin were dependent on PR55β in ACCS-M. Finally, we confirmed a correlation between PR55β staining intensity and histopathological type in human AdCC tissues., Conclusion: Our study provides new insight into the interaction between PR55β and β-catenin and suggests that PR55β may be a target for the clinical treatment of AdCC., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Salivary gland (SG) defects have a wide range of health implications, including xerostomia, bacterial infections, and oral health issues. Branching morphogenesis is critical for SG development. A clear understanding of the mechanisms underlying this process will accelerate SG regeneration studies. Fibroblast growth factor receptor 2 (FGFR2) interacts with multiple fibroblast growth factors (FGFs), which promote development. FGFR2 consists of two isoforms, FGFR2b and FGFR2c. FGFR2b is critical for SG development, but little is known about the expression and function of FGFR2c. We investigated the expression of all FGFR family members in fetal SGs between embryonic day 12.5 (E12.5) and E18.5. Based on RT-PCR, we observed an increase in the expression of not only Fgfr2b, but also Fgfr2c in early-stage embryonic mouse SGs, suggesting that FGFR2c is related to SG development. The branch number decreased in response to exogenous FGF2 stimulation, and this effect was suppressed by a mouse anti-FGFR2c neutralizing antibody (NA) and siRNA targeting FGFR2c, whereas FGFR2b signaling was not inhibited. Moreover, the expression of marker genes related to EMT was induced by FGF2, and this expression was suppressed by the NA. These results suggested that branching morphogenesis in SGs is regulated by FGFR2c, in addition to FGFR2b. Interestingly, FGFR2c signaling also led to increased fgf10 expression, and this increase was suppressed by the NA. FGFR2c signaling regulates branching morphogenesis through the activation of FGFR2b signaling via increased FGF10 autocrine. These results provide new insight into the mechanisms by which crosstalk between FGFR2b and FGFR2c results in efficient branching morphogenesis., (Copyright © 2016 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.)

Objective: For the definitive diagnosis of IgG4-related disease (IgG4-RD), biopsies of local lesions are recommended so as to exclude other diseases, including lymphoma and cancer. However, performing biopsies of underlying organs is technically difficult. In this study, we examined the diagnostic utility of labial salivary gland (LSG) biopsy as a less invasive procedure., Methods: Sixty-six patients with suspected IgG4-RD by clinical findings or high serum IgG4 underwent LSG biopsy. We examined the relationship between the number of IgG4-positive plasma cells in LSG and clinical findings., Results: The final diagnosis was 45 patients with IgG4-RD, 12 with Sjögren's syndrome, four with suspected Sjögren's syndrome, three with malignant lymphoma, one with systemic lupus erythematosus, and one with Warthin's tumor. The sensitivity, specificity, and accuracy of LSG biopsy were 55.6%, 100.0%, and 70.0%, respectively. Forty-five IgG4-RD patients were divided into two groups: 1) 25 with lesions of salivary glands (IgG4-RD S+) and 2) 20 without these lesions (IgG4-RD S-). Seventeen of 25 (68.0%) IgG4-RD S + and 8 of 20 (40.0%) IgG4-RD S - patients were positive for LSG biopsy. In the IgG4-RD S - patients, the mean number of affected organs and serum IgG4 in the positive cases for LSG biopsy were significantly higher than in the negative cases., Conclusion: A solo LSG biopsy is insufficient for the diagnosis of IgG4-RD because of its low sensitivity. However, LSG biopsy combined with clinical findings, including serum IgG4 and number of affected organs, may contribute towards a diagnosis of IgG4-RD patients with affected underlying organs.

Introduction: The aim of this study was to clarify the effectiveness of various imaging modalities and characteristic imaging features in the screening of IgG4-related dacryoadenitis and sialadenitis (IgG4-DS), and to show the differences in the imaging features between IgG4-DS and Sjögren's syndrome (SS)., Methods: Thirty-nine patients with IgG4-DS, 51 with SS and 36 with normal salivary glands were enrolled. Images of the parotid and submandibular glands obtained using sonography, 2-[(18)F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT), computed tomography (CT) and magnetic resonance imaging (MRI) were retrospectively analyzed. Six oral and maxillofacial radiologists randomly reviewed the arranged image sets under blinded conditions. Each observer scored the confidence rating regarding the presence of the characteristic imaging findings using a 5-grade rating system. After scoring various findings, diagnosis was made as normal, IgG4-DS or SS, considering all findings for each case., Results: On sonography, multiple hypoechoic areas and hyperechoic lines and/or spots in the parotid glands and obscuration of submandibular gland configuration were detected mainly in patients with SS (median scores 4, 4 and 3, respectively). Reticular and nodal patterns were observed primarily in patients with IgG4-DS (median score 5). FDG-PET/CT revealed a tendency for abnormal (18)F-FDG accumulation and swelling of both the parotid and submandibular glands in patients with IgG4-DS, particularly in the submandibular glands. On MRI, SS had a high score regarding the findings of a salt-and-pepper appearance and/or multiple cystic areas in the parotid glands (median score 4.5). Sonography showed the highest values among the four imaging modalities for sensitivity, specificity and accuracy. There were significant differences between sonography and CT (p = 0.0001) and between sonography and FDG-PET/CT (p = 0.0058) concerning accuracy., Conclusions: Changes in the submandibular glands affected by IgG4-DS could be easily detected using sonography (characteristic bilateral nodal/reticular change) and FDG-PET/CT (abnormal (18)F-FDG accumulation). Even inexperienced observers could detect these findings. In addition, sonography could also differentiate SS. Consequently, we recommend sonography as a modality for the screening of IgG4-DS, because it is easy to use, involves no radiation exposure and is an effective imaging modality.

Controlling metastatic lesions is an important part of improving cancer prognosis, in addition to controlling the primary lesion. There have been numerous histological studies on primary and metastatic lesions, but little basic research has been performed using cell lines from primary and metastatic lesions belonging to the same patient. In this study, we successfully established a cell line derived from lower gingival carcinoma (WK2) as well as a line derived from secondary cervical lymph node metastasis (WK3F) through primary cultures of tissue from a patient with oral squamous cell carcinoma. We then investigated the biological characteristics of the cancer cell lines from these primary and metastatic lesions and analyzed metastasis-related genes. Comparison of the biological characteristics in vitro showed that WK3F had higher cell proliferation ability and shorter cell doubling time than WK2. WK3F also had increased cell migratory ability and higher invasive and self-replication abilities. Heterotransplantation into nude mice resulted in high tumor formation rates in the tongue and high metastasis rates in the cervical lymph nodes. Changes in WK2 and WK3F gene expression were then comprehensively analyzed using microarrays. Genes with increased expression in WK3F compared to WK2 were extracted when the Z-score was ≥2.0 and the ratio was ≥5.0, while genes with reduced expression in WK3F compared to WK2 were extracted when the Z-score was ≤-2.0 and the ratio was ≤0.2; differences were found in 604 genes. From these, MAGEC1 (88.0-fold), MMP-7 (18.6-fold), SNAI1 (6.6-fold), MACC1 (6.2-fold), and HTRA1 (0.012-fold) were selected as metastasis-related candidate genes. The results suggest that these molecules could be important for clarifying the mechanisms that regulate metastasis and provide new therapeutic targets for inhibiting tumor invasion.

Objective: This study was undertaken to determine whether induction of systemic inflammation accelerates the development of Sjögren's syndrome (SS) in genetically susceptible mice., Methods: Female (NZB x NZW)F1 mice were treated with either Freund's incomplete adjuvant (IFA) or phosphate buffered saline (PBS) at monthly intervals. Salivary gland function was monitored by measuring pilocarpine-induced saliva volume. Mice were killed at different time points and examined for sialadenitis and salivary gland-infiltrating cells. Sera were analyzed for autoantibodies to salivary gland antigens, nuclear antigens, and Ro60., Results: While IFA-treated mice had significantly decreased salivary secretion 7 weeks after the initial treatment, salivary secretion did not decrease in PBS-treated controls until 17 weeks. At 7 weeks, the severity of sialadenitis and the number of T and B cells infiltrating the salivary glands did not differ between the 2 groups. However, at this time point IFA-treated mice showed significantly higher frequencies of CD11clow, B220+, Ly6C+, mouse PDCA-1+ dendritic cells (DCs) in the salivary glands. While levels of autoantibodies did not differ between the 2 groups at early time points, by late time points IFA-treated mice had higher levels. The gland dysfunction observed in IFA-treated mice at earlier time points did not correlate with the severity of sialadenitis or levels of autoantibodies. Instead, it was associated with increased frequency of plasmacytoid DCs in the gland., Conclusion: Our data suggest that generalized inflammatory stimuli can accelerate the development of SS-like disease in (NZB x NZW)F1 mice, and that gland dysfunction in SS can develop prior to the generation of a robust adaptive autoimmune response.

The genetic and environmental factors that control the development of Sjögren's syndrome, an autoimmune disease mainly involving the salivary and lacrimal glands, are poorly understood. Viruses which infect the glands may act as a trigger for disease. The ability of sialotropic murine CMV (MCMV) to induce acute and chronic glandular disease was characterized in an autoimmune-prone mouse strain, NZM2328. MCMV levels were detectable in the salivary and lacrimal glands 14-28 days after i.p. infection and correlated with acute inflammation in the submandibular gland. After latency, virus was undetectable in the glands by PCR. At this stage, NZM2328 female mice developed severe chronic periductal inflammation in both submandibular and lacrimal glands in contrast to the much milder infiltrates found in female B6-lpr and male NZM2328. The focal infiltrates consisted of CD4+ and B220+ cells as opposed to diffuse CD4+, CD8+, and B220+ cells during acute infection. Salivary gland functional studies revealed a gender-specific progressive loss of secretory function between days 90 and 125 postinfection. Latent MCMV infection did not significantly affect the low incidence of autoantibodies to Ro/SSA and La/SSB Ags in NZM2328 mice. However, reactivities to other salivary and lacrimal gland proteins were readily detected. MCMV infection did not significantly alter the spontaneous onset of kidney disease in NZM2328. Thus, chronic inflammation induced by MCMV with decreased secretory function in NZM2328 mice resembles the disease manifestations of human Sjögren's syndrome.

Ab responses directed against several ribonucleoprotein (RNP) Ags are a characteristic feature of systemic lupus erythematosus (SLE). Previous work in our laboratory using mouse model systems had revealed that both epitope spreading and inherent cross-reactivity between ribonucleoproteins contributes to the observed multiple specificities in autoimmune sera. We have now extended these studies to human autoimmune responses. Using purified polyclonal and mAbs derived from SLE patients, cross-reactivity between Ro60 and SmD was demonstrated. The cross-reactive epitope was mapped to nonhomologous regions on Ro60(481-505) and SmD(88-102). Five mAbs specifically recognized apoptotic cells, demonstrated variable levels of cross-reactivity toward other nonhomologous ribonucleoprotein targets and bound multiple, nonoverlapping and nonhomologous epitopes on Ro60. Our study demonstrates that cross-reactivity between frequently targeted autoantigens is an important aspect of human systemic autoimmune responses. The presence of multiple cross-reactive epitopes on Ro60 might be important for the generation of anti-Ro60 Ab in SLE patients and in normal individuals displaying no evidence of clinical disease.

We recently described that the SART-1(690-698) peptide could induce HLA-A24-restricted cytotoxic T lymphocytes (CTLs), which recognize the SART-1(259) (+) tumor cells from peripheral blood mononuclear cells (PBMCs) of HLA-A24(+) cancer patients. In our study, in 5 of 14 HLA-A24(+) patients with oral squamous cell carcinomas (SCCs), CTLs could be induced with the SART-1(690-698) peptide from the PBMCs. In 2 of the patients from whom the highest CTL activities were induced, the T-cell receptor (TCR) Vbeta repertoire expressed by the SART-1(690-698)-specific CTLs was found to be restricted and multiple Vbeta families were predominantly expressed in each patient. Although the predominant Vbeta families were different between the 2 patients, Vbeta7 was highly and commonly predominant. The same predominant Vbeta families were also detected in the tumor-infiltrating lymphocytes (TILs) from each patient, and each Vbeta family contained one or more unique T-cell clonotypes. The unique T-cell clonotypes were found to be common between the TILs and SART-1(690-698)-specific CTLs from each patient, and especially 2 T-cell clonotypes with Vbeta7 were identical even in the 2 patients. One of the 2 T-cell clonotypes with Vbeta7 was detected in the TILs from 11 of 14 HLA-A24(+) patients and another was found in those from 8 of HLA-A24(+) patients, while none of 10 HLA-A24(-) patients demonstrated both T-cell clonotypes. These results strongly suggest that the T-cell clonotypes with Vbeta7 are major TCR Vbeta genes expressed by SART-1(690-698)-specific CTLs. Furthermore, autologous tumor cells from one of the HLA-A24(+) patients stimulated the PBMCs and regional lymph node cells (LNCs) to expand the same T-cell clonotypes as those in the SART-1(690-698)-specific CTLs. These results strongly suggest that the SART-1(690-698)-specific CTLs clearly accumulate in vivo, especially in the TILs, as a consequence of in situ antigenic stimulation by autologous tumor cells. The identification of the unique TCR Vbeta genes used by SART-1(259)-specific CTLs should help to improve the diagnosis of the specific immune response in patients with SART-1(259) (+) cancers, especially during anticancer immunotherapy., (Copyright 2003 Wiley-Liss, Inc.)

Objective: To explore the potential of salivary gland epithelial cells to act as nonprofessional antigen-presenting cells (APC) in the development of Sjögren's syndrome (SS)., Methods: Expression of HLA-DR antigens, costimulatory molecules, and adhesion molecules on epithelial cells was immunohistochemically examined in labial salivary glands from patients with SS. An association with the expression of T cell derived cytokine messenger RNA (mRNA) was observed. The expression of these molecules was confirmed using cultured salivary gland epithelial cells. The ability of the salivary gland epithelial cells as nonprofessional APC was examined in a mixed culture system using the salivary gland epithelial cells and allogeneic lymphocytes., Results: Expression of HLA-DR antigens, CD80, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule (VCAM), and E-selectin was immunohistochemically detected on duct cells from all patients; however, the expression of CD86 was limited to only some patients. Concomitant expression of CD80 on duct cells and Th1 cytokine mRNA, and CD86 on duct cells and Th2 cytokine mRNA, was observed. Interferon-gamma (IFN-gamma) induced the cultured salivary gland epithelial cells to express HLA class I antigens, HLA-DR antigens, CD80, and ICAM-1, while tumor necrosis factor-alpha (TNF-alpha) induced the expression of HLA class I antigens, CD80, CD86, and VCAM. Cultured salivary gland epithelial cells treated with either IFN-gamma or TNF-alpha also caused allogeneic lymphocytes to proliferate., Conclusion: The ability of salivary gland epithelial cells to express HLA-DR antigens, costimulatory molecules, and adhesion molecules and thus to act as nonprofessional APC was suggested. CD80 and CD86 expression of these cells was also suggested to be involved in the activation of Th1 and Th2, respectively.