Expression and specific antibody-producing capacity of B lymphocytes infiltrating in lesions of patients with pemphigus vulgaris / 中华皮肤科杂志

Objective To evaluate the specific antibody-producing capacity of locally infiltrating B lymphocytes in lesions of patients with pemphigus vulgaris (PV).Methods Totally,35 patients with PV and 22 healthy controls were enrolled into this study.Skin tissues were resected from blisters or erosions of the patients with PV,and from normal skin of healthy controls.Then,mononuclear cells were isolated from these skin tissues.Flow cytometry was performed to determine the percentages of lymphocytes,CD 19+ B lymphocytes,and desmoglein (Dsg)1-and Dsg3-specific CD19+ B lymphocytes.B lymphocytes isolated from the lesional skin of patients with PV were cultured in vitro.Enzyme-linked immunosorbent assay (ELISA) was conducted to determine titers of anti-Dsg1 and anti-Dsg3 antibodies in the cell culture supernatant.Receiver operating characteristic (ROC) curve analysis was conducted to calculate positive rates of anti-Dsg1 and anti-Dsg3 antibodies.Results The percentages of lymphocytes (17.95％ ± 3.85％) and CD19+ B lymphocytes (4.27％ ± 1.13％) were significantly higher in the lesional skin of PV patients than in the normal skin of healthy controls (7.83％ ± 1.29％,0.61％ ± 0.31％ respectively;t =2.49,U =13.00 respectively,both P ＜ 0.05).Among the CD19+ B lymphocytes in the lesional skin of PV patients,the percentage of CD19qgG+ B cells was (38.33 ± 5.56)％,and percentages of Dsg1-and Dsg3-specific CD19+ B lymphocytes were 12.87％ ± 1.267％ and 10.42％ ± 1.243％ respectively.After the in vitro culture for 6 days,the titers of anti-Dsg1 and anti-Dsg3 antibodies in the cell culture supematant were (4.89 ± 1.56) U/ml and (35.45 ± 13.03) U/ml respectively,with their positive rates being 85％ (17/20)and 95％ (19/20) respectively.Conclusion There are Dsg1-and Dsg3-specific B lymphocytes aggregating in the lesional skin of patients with PV,which can produce anti-Dsg1 and anti-Dsg3 antibodies after in vitro culture.

Antigen-specific helper T cells in patients with pemphigus vulgaris / 中华皮肤科杂志

Objective To study the changes of antigen-specific T helper type 1 (Th1) cells and Th2 cells in patients with pemphigus vulgaris (PV) at different stages,so as to better understand the roles of autoreactive T cells in PV.Methods The DG3 (96-112) peptide was synthesized.Twenty-four patients with PV and 10 health checkup examinees were included in this study.Peripheral blood mononuclear cells (PBMCs) were obtained from the health checkup examinees and all the patients before treatment and seven patients about one month after treatment,and stimulated with the DG3 peptide of 10 mg/L for different durations.Then,enzyme-linked immunospot (ELISPOT) assay was performed to count the number of DG3-specific IFN-γ+ Th1 cells,IL-4+ Th2 cells and memory B cells.One-way analysis of variance (ANOVA) and t test were done to compare the number of cells between different groups,and Pearson correlation coefficient was used to evaluate the correlation among Th cells,memory B cells and anti-desmoglein 3 (Dsg3) antibody titers.Results In these patients,the male to female ratio was 1.67 ∶ 1,and the average age was (56.59 ± 14.66) years.Compared with the health check-up examinees,the patients with PV showed a higher absolute number of DG3-specific IFN-γ+ Th1 cells (420.18 ± 350.29 vs.145.12 ± 86.56,t =3.25,P ＜ 0.05),but a similar absolute number of specific IL-4+ Th2 cells (366.76 ± 192.44 vs.335.88 ± 164.96,P＞ 0.05) per 5 × 105 PBMCs.The percentage of DG3-specific IL-4+ Th2 cells in Th2 cells was 37.03％ ± 23.44％,and the percentage of IFN-γ+ Th1 cells was 23.62％ ± 16.77％ in peripheral blood of patients with PV.The number of DG3-specific IL-4+ Th2 cells per 5 × 105 PBMCs significantly decreased from 452.82 ± 199.29 before treatment to 241.68 ± 160.60 after treatment in seven patients (t =2.48,P ＜ 0.05).There was no significant correlation between specific Th cells,memory B cells and anti-Dsg3 antibody titers (all P ＞ 0.05).Conclusions The peptide DG3 (96-112) has pathogenic epitopes which could be recognized by specific Th cells of patients with PV.Both antigen-specific IFN-γ+ Th1 cells and IL-4+ Th2 cells play certain roles in the pathogenesis of pemphigns vulgaris,and IL-4+ Th2 cells appear to be more important.

Relationship of regulatory B cells with pathogenic antibodies in pemphigus / 中华皮肤科杂志

Objective To explore the mechanisms underlying the mediating effect of regulatory B (Breg)cells in the pathogenesis of pemphigus.Methods Peripheral blood specimens were collected from 48 patients with pemphigus at different degrees of severity and 20 healthy controls.Flow cytometry was conducted to analyze the frequency of Breg(CD19 +CD24hiCD38hi)cells in peripheral CD19+ B cells,enzyme linked immunosorbent assay(ELISA)to determine the titer and subtypes of anti-desmoglein(Dsg)1 and 3 antibodies in sera from these subjects.The relationship of anti-Dsg 1 and 3 antibodies with the frequency of Breg cells was assessed by Spearman's rank correlation test.Results Significant differences were observed in the proportion of Breg cells in CD19+ B cells between patients with pemphigus and healthy controls(11.54％ ± 0.97％ vs.8.19％ ± 0.85％,P =0.04),as well as between patients with acute mild pemphigus and those with moderate and severe pemphigus(5.17％ ± 2.14％ vs.11.38％ ± 5.30％ and 11.17％ ± 5.31％,P =0.042,0.046,respectively).The frequency of Breg cells was positively correlated with the absorbance value for anti-Dsg1 antibodies of IgG4 subclass and IgG4/IgG1 ratio(r =0.527,0.565,respectively,both P ＜ 0.01).Conclusions Breg cells are mainly associated with the production of antibodies in and disease severity of pemphigus,while the actual mechanism of action remains unknown.