Homozygous deletion of the DSG3 terminal exon associated with acantholytic blistering of the oral and laryngeal mucosa.

We report a novel homozygous 49.6 kb deletion of chromosome 18q12.1 involving the last exon of DSG3 in dizygotic twins with phenotype consistent with acantholytic blistering of the oral and laryngeal mucosa (ABOLM). The twin siblings presented predominantly with friability of the laryngeal and respiratory mucosa. This is only the second report in the literature of this unusual autosomal recessive blistering disorder. The diagnosis explains the mucosal phenotype of a pemphigus-like disorder without evidence of autoimmune dysfunction. The exclusion of an autoimmune basis has management implications. The deletion also involved the DSG2 gene, which is associated with arrhythmogenic right ventricular dysplasia (ARVD). The affected siblings and heterozygous parents do not show any cardiac phenotype at this time. Functional studies would further clarify how deletions resulting in loss of function of DSG3 may cause the reported phenotypes of DSG3-related ABOLM.

Case report: A rare case of imiquimod-induced atypical pemphigus vulgaris.

Background: Pemphigus vulgaris is an autoimmune intraepithelial bullous disease involving the skin and the mucous membranes. Imiquimod, a topical therapy for skin basal cell carcinoma, is an amine that induces the production of tumor necrosis factor alfa, interleukin-1 and other cytokines. Pemphigus induced by drugs has been frequently reported, mostly after systemic therapy. Case presentation: We present the case of a 50-year-old man who developed skin, intraoral, and genital mucosae lesions 3 days after a treatment with Imiquimod for multiple superficial basal cell carcinoma of the trunk. Direct and indirect immunofluorescence results were compatible with the diagnosis of pemphigus vulgaris. Enzyme-linked immunosorbent assay was negative for desmoglein 1 and 3, but interestingly, by immunoblotting on keratinocyte extracts a band of 170 kDa was obtained by IgG. The patient, after interrupting Imiquimod application, started a treatment with prednisolone and in 4 weeks showed a complete remission. Conclusion: Topical Imiquimod therapy might induce atypical pemphigus vulgaris in some patients.

Desmoglein 3 (Dsg3) expression in cancer: A tissue microarray study on 15,869 tumors.

Desmoglein-3 (Dsg3) is a transmembrane glycoprotein which is preferably found in desmosomes of keratinocytes in squamous epithelium. Both loss and upregulation of Dsg3 have been implicated in cancer progression. To comprehensively evaluate Dsg3 expression in normal and neoplastic tissues, a tissue microarray containing 15,869 samples from 137 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Dsg3 immunostaining was detectable in 47 (34.3 %) tumor categories including 15 (10.9 %) tumor types with at least one strongly positive case. The highest rate of Dsg3 positivity was found in squamous cell carcinomas from various sites (71.2-97.3 %), basal cell carcinomas of the skin (41.9 %), various tumors from salivary glands (12.9-38.9 %), and in urothelial neoplasms (2.1-20.7 %). Dsg3 positivity in less than 10 % of cases was seen in 23 additional cancer categories. Dsg3 staining was almost always weak and rarely moderate in these tumors. High Dsg3 expression was linked to invasive growth in urothelial carcinoma (p < 0.0001), as well as to advanced pT stage (p = 0.0102), nodal metastasis (p = 0.0162), blood vessel infiltration (p = 0.0189) and lymph vessel infiltration (p = 0.0151) in colorectal cancer. Reduced Dsg3 expression was linked to high grade in a cohort of 599 squamous cell carcinomas from 11 different sites of origin (p < 0.0001). Associations between Dsg3 immunostaining and clinicopathological features were not found in invasive breast cancer of no special type, ductal adenocarcinomas of the pancreas and in gastric adenocarcinomas. In summary, Dsg3 expression predominates in squamous cell carcinomas and loss of Dsg3 immunostaining goes along with dedifferentiation of these tumors. The identification of focal squamous differentiation in other neoplasms may constitute a diagnostic application of Dsg3 immunohistochemistry.

Role of ADAM10 and ADAM17 in the Regulation of Keratinocyte Adhesion in Pemphigus Vulgaris.

The severe autoimmune blistering disease Pemphigus vulgaris (PV) is mainly caused by autoantibodies (IgG) against desmoglein (Dsg) 3 and Dsg1. The mechanisms leading to the development of blisters are not fully understood, but intracellular signaling seems to play an important role. Sheddases ADAM10 and ADAM17 are involved in the turnover of the desmosomal cadherin Dsg2 and ADAM10 has been shown to contribute to acantholysis in a murine pemphigus model. In the present study, we further examined the role of ADAM10 and ADAM17 both in keratinocyte adhesion and in the pathogenesis of PV. First, we found that inhibition of ADAM10 enhanced adhesion of primary human keratinocytes but not of immortalized keratinocytes. In dissociation assays, inhibition of ADAM10 shifted keratinocyte adhesion towards a hyperadhesive state. However, ADAM inhibition did neither modulate protein levels of Dsg1 and Dsg3 nor activation of EGFR at Y1068 and Y845. In primary human keratinocytes, inhibition of ADAM10, but not ADAM17, reduced loss of cell adhesion and fragmentation of Dsg1 and Dsg3 immunostaining in response to a PV1-IgG from a mucocutaneous PV patient. Similarly, inhibition of ADAM10 in dissociation assay decreased fragmentation of primary keratinocytes induced by a monoclonal antibody against Dsg3 and by PV-IgG from two other patients both suffering from mucosal PV. However, such protective effect was not observed in both cultured cells and ex vivo disease models, when another mucocutaneous PV4-IgG containing more Dsg1 autoantibodies was used. Taken together, ADAM10 modulates both hyperadhesion and PV-IgG-induced loss of cell adhesion dependent on the autoantibody profile.

Recombinant Fragment of the Extracellular Domain of Human Desmoglein 3 Fused with the Fc-Fragment of Human IgG1 Selectively Adsorbs Autoreactive Antibodies from the Sera of Pemphigus Patients.

Using the recombinant second fragment of the extracellular domain (EC2) of human desmoglein type 3 (Dsg3) as an affinity ligand, an immunosorbent was obtained that selectively binds autoreactive antibodies to this domain from the immune sera of patients with pemphigus. The EC2 protein was obtained in the form of a fusion protein with the Fc-fragment of human IgG1. The production was carried out in CHO cells using the method of transient expression.

Expression and clinical significance of CK5／6,DSG3,P40,TTF-1,CK7,NapsinA in small biopsy specimens of non-small cell lung cancer / 中国基层医药

Objective To detect the expression and the differential significance of CK 5／6,DSG3,P40,TTF-1,CK7,NapsinA in small biopsy specimens of non -small cell lung cancer ( NSCLC),squamous cell carcinoma (SCC) and adenocarcinoma (AC).Methods Immunohistochemical SP method was used to detect the expressions of CK5／6,DSG3,P40,TTF-1,CK7 and NapsinA in 120 small biopsy specimens of NSCLC hospitalized in the Central People's Hospital of Tengzhou from January 2016 to December 2017,and the results were analyzed combined with the clinical characteristics of NSCLC.Results The positive expression rates of CK5／6,DSG3 and P40 in lung SCC were 100.0%(56／56),89.3%(50／56) and 96.4%(54／56), respectively,with specificity of 90.6%,100.0% and 100.0%,respectively.The positive expression rates of NapsinA ,TTF-1 and CK7 in lung AC were 81.3%(52／64), 90.6%(58／64) and 93.8%(60／64),respectively,with specificity of 100.0%,92.9% and 96.4%,respectively. The positive expression rates of CK5／6,DSG3,P40 in SCC had statistically significant differences compared with those in AC (all P＜0.05),and the expression of TTF -1,CK7 and NapsinA in AC had statistically significant differences compared with those in SCC ( all P＜0.05).Conclusion CK5／6,DSG3,P40,TTF-1,CK7 and NapsinA are of great significance in the differential diagnosis of SCC and AC in small biopsy specimens of NSCLC .

Expression and clinical significance of CK5/6, DSG3, P40, TTF-1, CK7, NapsinA in small biopsy specimens of non-small cell lung cancer / 中国基层医药

Objective@#To detect the expression and the differential significance of CK5/6, DSG3, P40, TTF-1, CK7, NapsinA in small biopsy specimens of non-small cell lung cancer (NSCLC), squamous cell carcinoma (SCC) and adenocarcinoma (AC).@*Methods@#Immunohistochemical SP method was used to detect the expressions of CK5/6, DSG3, P40, TTF-1, CK7 and NapsinA in 120 small biopsy specimens of NSCLC hospitalized in the Central People's Hospital of Tengzhou from January 2016 to December 2017, and the results were analyzed combined with the clinical characteristics of NSCLC.@*Results@#The positive expression rates of CK5/6, DSG3 and P40 in lung SCC were 100.0%(56/56), 89.3%(50/56) and 96.4%(54/56), respectively, with specificity of 90.6%, 100.0% and 100.0%, respectively.The positive expression rates of NapsinA, TTF-1 and CK7 in lung AC were 81.3%(52/64), 90.6%(58/64) and 93.8%(60/64), respectively, with specificity of 100.0%, 92.9% and 96.4%, respectively.The positive expression rates of CK5/6, DSG3, P40 in SCC had statistically significant differences compared with those in AC (all P<0.05), and the expression of TTF-1, CK7 and NapsinA in AC had statistically significant differences compared with those in SCC (all P<0.05).@*Conclusion@#CK5/6, DSG3, P40, TTF-1, CK7 and NapsinA are of great significance in the differential diagnosis of SCC and AC in small biopsy specimens of NSCLC.

Evaluation of Serum Desmoglein 1 and Desmoglein 3 in Oral Erosive Lichen Planus before and after Topical Application of Tacrolimus.

AIM: The current study will attempt to throw light on the role of desmoglein 1 and desmoglein 3 in the pathogenesis of erosive lichen planus and their response to topical application of tacrolimus. MATERIALS AND METHODS: Twenty patients with erosive oral lichen planus received tacrolimus ointment three times daily for eight weeks. Assessments using the clinical score and a visual analog scale were recorded at each visit. Serum concentrations of circulating autoantibodies to desmoglein 1 and desmoglein 3 will be determined by enzyme-linked immunosorbent assay (ELISA) at baseline, four weeks and eight weeks after treatment. Statistical software SPSS v.17.0 was used for statistical analysis. RESULTS: All patients showed significant improvement in all outcomes within the follow-up periods when compared with the baseline (p < 0.05). The mean value of the visual analog scale were 8.30 ± 1.49, 4.15 ± 1.14, 2.10 ± 0.91, 0.90 ± 0.79, and 0.0 ± 0.0 starting from baseline to the end of follow up period. The mean value of the clinical score were 4.7 ± 0.48, 2.9 ± 1.29, 1.8 ± 1.32, 1.31 ± 0.69, and 0.69 ± 0.09 starting from baseline to the end of follow-up period. There was a significant decrease in the levels of anti-Dsg1 and anti-Dsg3, during the follow-up period (p < 0.05). CONCLUSION: The concluded data suggest that antibodies against desmoglein 1 and desmoglein 3 seem to play a key role in the pathogenesis of oral lichen planus. Also, there is a significant decrease in the level of anti-Dsgl and anti-Dsg3 autoantibodies with topical tacrolimus 0.1% ointment. CLINICAL SIGNIFICANCE: Monitoring the serum level of antibodies against keratinocyte cadherins Dsg 1 and Dsg 3 can be used to evaluate the effect of topical application of tacrolimus on Erosive Oral lichen planus.

Sequence Characterization of DSG3 Gene to Know Its Role in High-Altitude Hypoxia Adaptation in the Chinese Cashmere Goat.

The Tibetan cashmere goat is one of the main goat breeds used by people living in the plateau. It exhibits the distinct phenotypic characteristics observed in lowland goats, allowing them to adapt to the challenging conditions at high altitudes. It provides an ideal model for understanding the genetic mechanisms underlying high-altitude adaptation and hypoxia-related diseases. Our previous exome sequencing of five Chinese cashmere breeds revealed a candidate gene, DSG3 (Desmoglein 3), responsible for the high-altitude adaptation of the Tibetan goat. However, the whole DSG3 gene (44 kbp) consisting of 16 exons in the goat genome was not entirely covered by the exome sequencing. In this study, we resequenced all the 16 exons of the DSG3 gene in ten Chinese native goat populations. Twenty-seven SNP variants were found between the lowland and highland goat populations. The genetic distance (FST ) of significant SNPs between the lowland and highland populations ranged from 0.42 to 0.58. By using correlation coefficient analysis, linkage disequilibrium, and haplotype network construction, we found three non-synonymous SNPs (R597E, T595I, and G572S) in exon 5 and two synonymous SNPs in exons 8 and 16 in DSG3. These mutations significantly segregated high- and low-altitude goats in two clusters, indicating the contribution of DSG3 to the high-altitude hypoxia adaptation in the Tibetan goat.

A novel lateral flow immunoassay for the rapid detection of anti-Dsg3 IgG serum autoantibodies in pemphigus vulgaris.

Pemphigus vulgaris (PV) is a severe autoimmune blistering disease of the skin and mucous membranes. As autoantibodies play an essential role in the disease pathogenesis, the serological detection of anti-desmoglein 3 IgG represents a central tool in the diagnosis of the disease. In this study, we show the validation of a novel lateral flow immunoassay (LFIA) which rapidly detects anti-desmoglein 3 (Dsg3) IgG in human serum. In contrast to other diagnostic procedures, the assay is compact and simple to perform and delivers a fast "yes" or "no" answer within 10 minutes without additional hardware requirements for test evaluation. For validation, a blinded collection of 200 sera including 100 sera from 14 PV patients, 75 sera from 24 bullous pemphigoid patients and 25 sera from 6 patients with pemphigus foliaceus collected at different time points during disease was used. Presence or non-presence of anti-Dsg3 IgG within sera was confirmed using a commercially available Dsg3-ELISA. For qualitative evaluation, Dsg3-LFIA test results were assessed by two independent groups of human observers. Furthermore, quantitative evaluation using POCScan reader was applied. The Dsg3-LFIA demonstrated reliable test results with a sensitivity and specificity of 78.1% and 97.1%, respectively. Test results from POCScan and human observers showed a substantial agreement. The Dsg3-LFIA represents a new diagnostic tool for the immediate and reliable detection of anti-desmoglein 3 serum IgG autoantibodies that does not require additional hardware. Further prospective trials are warranted to validate the Dsg3 LFIA in pemphigus.

Prognostic significance of VEGF-C in predicting micrometastasis and isolated tumour cells in N0 oral squamous cell carcinoma.

BACKGROUND: Lymph node metastasis in oral squamous cell carcinoma (OSCC) is a well-known independent prognostic factor. However, the identification of occult tumour cells within the lymph nodes has remained a challenge for the pathologist as well as the clinician. OBJECTIVE: The aim of this study was to determine the prevalence of micrometastasis and isolated tumour cells (ITCs) in pathologically staged N0 OSCC of the tongue and buccal mucosa and to assess its correlation with vascular endothelial growth factor C, (VEGF-C) expression in the primary tumour. METHODS: Thirty-four cases of N0 OSCC comprising of 17 cases each from the tongue and buccal mucosa were evaluated by immunohistochemistry for VEGF-C expression. The corresponding lymph nodes from levels I and II were pathologically examined and cross-detected for micrometastasis and ITCs with desmoglein 3 (DSG3). RESULTS: The prevalence of micrometastasis and ITCs in OSCC of the tongue and buccal mucosa was 23.5% and 17.6%, respectively. A total of 12 out of 151 lymph nodes contained micrometastatic tumour foci and ITCs. A higher expression of VEGF-C in the primary tumour was associated with a greater probability for the occurrence of micrometastasis and ITCs in the lymph nodes. CONCLUSION: High expression of VEGF-C in the primary tumour may be a good determinant for detection of occult tumour cells in the lymph nodes of OSCC cases.

Prognostic significance of DSG3 in rectal adenocarcinoma treated with preoperative chemoradiotherapy.

AIM: This study aimed to investigate the prognostic significance of DSG3 and its association with response to neoadjuvant concurrent chemoradiotherapy (CCRT) in rectal cancer. MATERIALS & METHODS: Data mining of a publicly available dataset was performed to find genes associated with CCRT response. Immunohistochemistry was applied to evaluate DSG3 expression. The relationships between DSG3 expression and various clinicopathological parameters and survival were analyzed. RESULTS: The DSG3 gene was significantly associated with CCRT response. The expression of DSG3 negatively correlated with poorer tumor regression (p < 0.001) and had an independent negative impact on disease-specific survival (p = 0.011), local recurrence-free survival (p = 0.031) and metastasis-free survival (p = 0.029). CONCLUSION: DSG3 was a key prognostic factor and predictor for CCRT response in rectal cancer patients.

Induction of T regulatory cells by the superagonistic anti-CD28 antibody D665 leads to decreased pathogenic IgG autoantibodies against desmoglein 3 in a HLA-transgenic mouse model of pemphigus vulgaris.

Pemphigus vulgaris (PV) is a potentially life-threatening autoimmune disease of the skin and mucous membranes. Its pathogenesis is based on IgG autoantibodies that target the desmosomal cadherins, desmoglein 3 (Dsg3) and desmoglein 1 (Dsg1) and induce intra-epidermal loss of adhesion. Although the PV pathogenesis is well-understood, therapeutic options are still limited to immunosuppressive drugs, particularly corticosteroids, which are associated with significant side effects. Dsg3-reactive T regulatory cells (Treg) have been previously identified in PV and healthy carriers of PV-associated HLA class II alleles. Ex vivo, Dsg3-specific Treg cells down-regulated the activation of pathogenic Dsg3-specific T-helper (Th) 2 cells. In this study, in a HLA-DRB1*04:02 transgenic mouse model of PV, peripheral Treg cells were modulated by the use of Treg-depleting or expanding monoclonal antibodies, respectively. Our findings show that, in vivo, although not statistically significant, Treg cells exert a clear down-regulatory effect on the Dsg3-driven T-cell response and, accordingly, the formation of Dsg3-specific IgG antibodies. These observations confirm the powerful immune regulatory functions of Treg cells and identify Treg cells as potential therapeutic modulators in PV.

E-cadherin and Src associate with extradesmosomal Dsg3 and modulate desmosome assembly and adhesion.

Desmosomes provide strong intercellular cohesion essential for the integrity of cells and tissues exposed to continuous mechanical stress. For desmosome assembly, constitutively synthesized desmosomal cadherins translocate to the cell-cell border, cluster and mature in the presence of Ca(2+) to stable cell contacts. As adherens junctions precede the formation of desmosomes, we investigated in this study the relationship between the classical cadherin E-cadherin and the desmosomal cadherin Desmoglein 3 (Dsg3), the latter of which is indispensable for cell-cell adhesion in keratinocytes. By using autoantibodies from patients with the blistering skin disease pemphigus vulgaris (PV), we showed in loss of function studies that E-cadherin compensates for effects of desmosomal disassembly. Overexpression of E-cadherin reduced the loss of cell cohesion induced by PV autoantibodies and attenuated activation of p38 MAPK. Silencing of E-cadherin abolished the localization of Dsg3 at the membrane and resulted in a shift of Dsg3 from the cytoskeletal to the non-cytoskeletal protein pool which conforms to the notion that E-cadherin regulates desmosome assembly. Mechanistically, we identified a complex consisting of extradesmosomal Dsg3, E-cadherin, ß-catenin and Src and that the stability of this complex is regulated by Src. Moreover, Dsg3 and E-cadherin are phosphorylated on tyrosine residues in a Src-dependent manner and Src activity is required for recruiting Dsg3 to the cytoskeletal pool as well as for desmosome maturation towards a Ca(2+)-insensitive state. Our data provide new insights into the role of E-cadherin and the contribution of Src signaling for formation and maintenance of desmosomal junctions.

The imbalance of Th17 and regulatory T cells in pemphigus patients.

UNLABELLED: Pemphigus is a complex dermatologic autoimmune bullous disease whose pathogenic mechanism is not fully understood. Anti-desmoglein-1 (Dsg1) and anti- Dsg3 autoantibodies play an important role in the pathogenesis of pemphigus. OBJECTIVES: To investigate the role of T-helper17 (Th17) and regulatory T (Treg) cells in the pathogenesis of pemphigus in fifty-one patients and twenty-six healthy individuals (control group). METHODS: Levels of CD3(+)CD8(-) IL-17 expressing Th cells and CD4(+)CD25(hi)Foxp3(+) Treg cells were determined by FACS in both groups, along with anti-Dsg1 and Dsg3 antibody titers. An analysis of the correlation between Th17 and Treg cells was performed. RESULTS: Th17 cell numbers were significantly higher in pemphigus patients than in normal controls (P = 0.014), especially in the acute onset and chronic active stages (P = 0.004 and 0.022). Conversely, Treg cells in pemphigus patients were significantly fewer than in the control group (P<0.001). The same trend was observed between the acute onset and the remittent stage patients (P = 0.006). We found a negative correlation between Th17 and Treg cell populations (r = -0.532, P<0.001). Anti-Dsg1 and Dsg3 antibody titers were higher in patients in the active stage than in the remittent stage, with an increased IgG4/IgG1 subclass ratio. There was no statistically significant correlation between Th17/Treg ratios and anti-Dsg1 or Dsg3 antibody titers. CONCLUSION: These findings show an imbalance of Th17 and Treg cell populations in pemphigus patients, which might result in the activation and proliferation of effector T cells, further up-regulating B cell activity and antibody production.

Evaluation of commercially available ELISA assays as a tool for monitoring and managing pemphigus patients: a prospective study.

BACKGROUND: Pemphigus is a potentially life-threatening auto-immune blistering disease and consequently it is important to monitor disease activity. OBJECTIVES: To assess the usefulness of serial antibody titers in the management of pemphigus and to predict disease activity in the clinical follow-up of pemphigus patients. MATERIALS AND METHODS: In this prospective observational study, seven patients with pemphigus vulgaris and three patients with pemphigus foliaceus were examined on a monthly basis for 24 months, or two-weekly during active disease. Disease activity was registered according to a new score system. RESULTS: A total of 158 samples were tested using commercial desmoglein (Dsg) 1 and Dsg3 enzyme-linked immunosorbent assay (ELISA) kits. The 20 U/mL cut-off for the anti-Dsg1 ELISA value was associated with a significantly higher risk of a skin activity score>0 (OR=7.91, 95% CI=1.71;36.65, p=0.01). A cut-off for disease activity at 5 gave an OR of 11.40 (95% CI=2.64;49.09, p=0.003). Dsg1 values of >15 had a sensitivity of 79.41% and specificity of 87.80% for predicting a relapse of skin disease in pemphigus patients. For Dsg3, no odds could be calculated for mucosal involvement, nor a predicting value for mucosal relapse. CONCLUSION: We conclude that only Anti-Dsg1 antibody ELISA values seem valuable in the follow-up of pemphigus patients and carry a predictive value. However, serial antibody titers cannot be seen as absolute indicators of disease activity and we believe that both Dsg1 and Dsg3 ELISA tests should be used with caution to monitor disease activity.

Pathogenic activity of circulating anti-desmoglein-3 autoantibodies isolated from pemphigus vulgaris patients.

INTRODUCTION: There are scarce data on immunochemical properties of pemphigus antibodies detected in clinical remission in pemphigus vulgaris (PV) patients. The aim of the study was to compare biological activity of anti-Dsg3 autoantibodies purified from the sera of PV patients in active stage and in clinical remission. MATERIAL AND METHODS: The effect of purified antibodies on expression of procaspase-3, Bax, Bcl-2, uPAR, IL-1ß, IL-6, and TNF-α mRNAs in the HaCaT keratinocytes was evaluated by Western blot and RT-PCR method. RESULTS: Incubation of HaCaT cells with anti-Dsg-3 autoantibodies caused their binding to cell membranes surfaces. Anti-Dsg3 autoantibodies isolated from the patients in active stage and clinical remission showed proapoptotic effect, caused enhanced expression of analyzed proinflammatory cytokines' mRNAs and uPAR mRNA. CONCLUSIONS: Our data revealed similar pathogenic activity of anti Dsg-3 autoantibodies isolated from active and clinical remission PV patients.

Study on Dsg3 induced activation of T cells in first degree relatives of patients with pemphigus vulparis / 中华微生物学和免疫学杂志

Objective To investigate The Th1/Th2 and Tc1/Tc2 polarization in the peripheral blood of first degree relatives of pemphigus vulgaris(PV) and healthy control individuals, and to approach the mechanism of the Dsg3-specific autoimmunity in PV. Methods The peripheral blood mononuclear cells (PBMC) from first degree relatives and healthy control was stimulated for72 h with Dsg3 and without Dsg3. Th1/Th2, Tc1/Tc2 was assessed by four-color flow cytometry. Results The mean frequency of Dsg3-spe-cific Th2 cells for PV antibody positive first degree relatives was 10.13%±3.72%, compared with stimula-tion without antigen 7.28%±3.58%, the difference was significant (P<0.05). The percentage Dsg3-spe-cific Th2 was markedly higher in the PV antibody positive first degree relatives group than that in the control group(10.13%±3.72% vs 6.10%±2.82%, P<0.05) , Tc2 was markedly higher also (20.01%± 10.43% v514.91%±8.06%, 20.01%±10.43% vs 9.58%±5.49%, P<0.05). Conclusion When Dsg3 stimulated PBMC were used to stimulate autologous T cells an increased amount of Th2 and Tc2 was observed, it is implied that the imbalance of Th1/Th2, Tc1/Tc2 might play an important role in the initia-tion of PV.