Objective To investigate the methylation status of Foxp3 gene and its roles in immunological pathogenesis of Kawasaki disease(KD). Methods Thirty children with KD and eighteen agematched healthy children consented to participate in this study. Quantitative methylation specific polymerase chain reaction(MSQP) was used to assess the methylation status of Foxp3 promoter and regulatory T cells specific demethylated region(TSDR) in CD4+ T cells. The proportion of CD4+ CD25 + Foxp3 + regulatory T (Tr) cells was analyzed by flow cytometry. Transcriptional levels of CD4+ CD25 + Foxp3 + Tr associating genes (Foxp3, CTLA4, GITR, LAG3 and CCR8 ) and Foxp3-dependent molecules (UBD and LGAIS3)were measured by real-time PCR. Results ( 1 ) Demethylation level of Foxp3 promoter in CD4 + T cells from patients with KD was lower significantly than that of health subjects( P ＜ 0.01 ), and increased significantly after treated with intravenous gamma globulin therapy(IVIG) (P ＜ 0.01 ). No difference of demethylation level of TSDR region was observed among all groups ( P ＞ 0. 05 ). ( 2 ) The proportion of CD4 + CD25 + Foxp3 + Tr in peripheral blood from patients with KD , as well as mRNA levels of Foxp3 gene in CD4+ T cells, was significantly lower than those of health subjects ( P ＜0. 01 ), and increases significantly after IVIG therapy (P ＜0.01 ). Significant positive correlations between demethylation level of Foxp3 promoter and the proportion of CD4 + CD25 + Foxp3 + Tr , or expression levels of Foxp3 in CD4 + T cells, were observed during acute phase of KD (CD4+CD25+ Foxp3+ Tr: r=0.76, P＜0. 01; Foxp3: r=0.89, P＜0. 01). (3)Transcription level of CD4+ CD25+ Foxp3+ Tr associating factors, such as CTLA4, GITR, LAG3 and CCR8, was significantly down-regulated in acute phase of KD(P＜0. 01 ), and up-regulated to some extent after treated with IVIG(P ＜0. 01 ). Expression levels of Foxp3-dependent molecules UBD and LGALS3 in CD4 + T cells decreased significantly during acute phase of KD (P ＜ 0.01 ), and basically recovered to the levels of health subjects( P ＜ 0.01 ). Conclusion Decrease of demethylation level of Fopx3 promoter is correlated with immune dysfunction in Kawasaki disease.

Objective To investigate the role of regulatory B cells ( Breg ) in the immunological pathogenesis of Kawasaki disease ( KD) .Methods Twenty-eight children with acute KD and twenty-eight age-matched healthy subjects were enrolled in this study .Blood samples were collected before and after the treatment of intravenous immunoglobulin (IVIG).The proportions of CD19+CD24hiCD38hi Breg and CD4+CD25+Foxp3+regulatory T cells (Treg), and the expressions of co-stimulatory molecules (CD80, CD86 and PD-L1) were analyzed by flow cytometry .The concentration of IL-10 protein was measured by enzyme-linked immunosorbent assay .Real-time PCR was performed to evaluate the expressions of Foxp 3, CTLA4 and GITR in CD4+T cells and IL-10 in CD19+B cells at mRNA level.Results (1) The proportions of CD19+CD24hi CD38hi Breg in peripheral blood and the expressions of IL-10 at mRNA level in CD19+B cells from patients with KD were lower than those from healthy controls (P<0.05), but significantly increased after treated with IVIG (P<0.05).Upon stimulation of lipopolysaccharide for 48 hours, the concentrations of IL-10 protein in culture supernatant of B cells from patients with KD were still lower than those from healthy controls [(31.06±8.26) pg/ml vs.(46.32±13.91) pg/ml, P<0.05].(2) Compared with healthy controls , the expressions of CD80, CD86 and PD-L1 were remarkably down-regulated in patients with acute KD ( P<0.05).With the treatment of IVIG, the expressions of CD80 and CD86 were significantly up-regulated though lower than those of the control group (P<0.05).There was no significant difference in the expression of PD-L1 before and after treatment (P>0.05).(3) The proportions of CD4+CD25+Foxp3+Treg and the expressions of Foxp3, CTLA-4 and GITR at mRNA level were significantly decreased in KD group compared with those in control group (P<0.05), but were increased to some extent after IVIG treatment (P<0.05). In addition, a positive correlation between the proportion of CD 19+CD24hiCD38hi Breg and the proportion of CD4+CD25+Foxp3+Treg was found in patient with acute KD (r=0.62, P<0.05).Conclusion Breg cell deficiency and its impaired function might be one of the important factors causing immune dysfunction in pa -tients with acute KD .

Objective To investigate the changes and significance of ubiquitination of Foxp3 pro-tein during the acute phage of Kawasaki disease ( KD) .Methods Forty-eight children with KD and twenty-eight age-matched healthy children were recruited in this study.Co-immunoprecipitation and Western blot assays were performed to determine the poly-ubiquitination status of Foxp3 in CD4+T cells.The percentages of CD4+CD25high Foxp3+regulatory T cells ( Treg) and the levels of IL-10, transforming growth factor-β( TGF-β) , cytotoxic T lymphocyte-associated protein-4 ( CTLA4 ) , STIP1 homology and U-Box containing protein 1 (STUB1), heat shock protein 70 (HSP70), ubiquitin-specific-processing protease 7 (USP7) and pSTAT3 were analyzed by flow cytometry analysis.Quantitative real-time PCR was used to evaluate the tran-scription levels of TLR1-10, IL-1R1, IL-1RAP, IL-6Rα, gp130, TNFR1, MyD88 and RIP1 in CD4+T cells.Plasma concentrations of IL-1β, IL-6 and TNF-αwere measured by enzyme-linked immunosorbent as-say.Results (1) The percentages of Treg cells and the levels of IL-10, TGF-β, CTLA4 and forkhead box P3 (Foxp3) in patients with acute KD were lower than those of healthy subjects (P<0.05), while the poly-ubiquitination of Foxp3 protein was significantly enhanced in patients with acute KD [(0.52 ±0.19) vs (0.08±0.02),P<0.05].Meanwhile, the four former items in KD patients with coronary artery lesions (KD-CAL+) were lower than those of KD patients without coronary artery lesions (KD-CAL-) (P<0.05), while the polyubiquitination level of Foxp3 protein in KD-CAL+group was much higher than that of KD-CAL-group [(0.70±0.28) vs (0.43±0.17), P<0.05].The levels of Treg cells, IL-10, TGF-βand CTLA4 in patients with KD were increased and the ubiquitination of Foxp3 protein was inhibited [(0.24±0.10) vs (0.52±0.19), P<0.05] upon the treatment with IVIG.(2) The levels of STUB1 and HSP70 in CD4+T cells were significantly elevated during acute KD, while the levels of USP7 were decreased (P<0.05).The ratios of STUB1/USP7 in patients with acute KD were much higher than those of the control group [(2.65± 0.92) vs (1.09±0.37), P<0.05], but were significantly decreased after IVIG therapy [(1.46±0.53) vs (2.65±0.92), P<0.05].A negative correlation was found between STUB1/USP7 ratio and Foxp3 level during acute KD (r=-0.56, P<0.05).Moreover, KD patients with CAL+showed higher levels of STUB1 and HSP70 and higher ratios of STUB1/USP7 (P<0.05), but lower levels of USP7 as compared with those of KD-CAL-group (P<0.05).(3) The plasma concentrations of inflammatory cytokines (IL-1β, IL-6 and TNF-α), the levels of surface receptors ( IL-1R1/IL-1RAP/TLR4, IL-6Rα/gp130 and TNFR1) and its downstream molecules ( MyD88, pSTAT3 and RIP1) in CD4+T cells were up-regulated during acute KD ( P<0.05), especially in patients with CAL+, but were down-regulated upon the IVIG therapy (P<0.05).No significant differences with other TLRs were found among the groups (P>0.05).Conclusion Hyper-ubiq-uitination of Foxp3 protein might be involved in the immune dysfunction during Kawasaki disease.

Objective To investigate the effects of polycyclic aromatic hydrocarbons ( PAHs) on regulatory T ( Treg) cells in newborns.Methods Blood samples were taken from the umbilical cord of sev-en newborn babies.CD4+CD25+T cells were isolated and treated with or without 300 nmol/L of phenan-threne for 72 hours in the presence of 100 IU/ml of IL-2.The expression of forkhead box P3 (Foxp3), sig-nal transducer and activator of transcription 3 (STAT3) and STAT5 were analyzed by 8-color flow cytometry. RT-PCR was performed to detect the expression of DNA ( cytosine-5 )-methyltransferase 1 ( DNMT1 ) , DNMT3a, DNMT3b and IL-4 at mRNA level.Pyrosequencing in combination with bisulphite sequencing was used to evaluate the methylation within the promoter and the Treg-specific demethylated region ( TSDR) of Foxp3 locus.Treg cells were cultured for 7 hours with autologous Tresp at Tresp/Treg ratios of 1 ∶1, 2 ∶1, 4 ∶1 and 8 ∶1 and stimulated with anti-CD3/CD28 beads and IL-2 for the evaluation of the immunosuppres-sive activities of Treg cells.Results (1) PAHs inhibited the expression of Foxp3 and the function of Treg cells collected from newborns.(2) PAHs significantly decreased the expression of STAT5 and Foxp3, but increased the expression of STAT3 (P<0.05).(3)PAHs enhanced the methylation of the promoter and the TSDR within Foxp3 gene.(4) The transcription levels of DNMT1, DNMT3a and DNMT3b in PAHs treated group were significantly higher than those of the control group (P<0.05).(5) More IL-4 was secreted by PAHs treated CD4+CD25+T cells, indicating that IL-4 was negatively correlated with STAT5, but positively correlated with STAT3.Conclusion PAHs decreased the number and inhibited the function of Treg cells in newborns.The possible mechanism might be related to the abnormal expression of STAT3 and STAT5 in-duced by IL-4 as well as the methylation within Foxp3 gene.

Objective To investigate the role of IL-35-producing regulatory B cells(IL-35 + Breg)in immunological pathogenesis of Kawasaki disease (KD).Methods Thirty-two children with KD and 28 age-matched healthy children were allowed to participate in this study.Flow cytometry was performed to evaluate the proportions of IL-35 + Breg as well as requlatory T cells (Treg)and expression levels of associated molecules such as programmed death-ligand 1 (PD-LI),CD169,programmed death 1 (PD-1),CD43,IL-12p35,epstein-Barr virus induced 3 (IL-27 EBI3).IL-12 receptor beta 2 (IL-12 Rβ2),IL-27 receptor alpha (IL-27 Rα),phosphated signal transducer and activator of transcription 1 (pSTAT1) and phosphated signal transducer and activator of transcription 3 (pSTAT3).Transcription levels of the Src homology 2 domain-containing protein tyrosine phosphatase 2 (SHP-2),phosphatase and tensin homolog (PTEN),vav1 guanine nucleotide exchange factor(Vav) in CD19 + B cells were determined by using quantitative real-time PCR.Plasma concentrations of IL-35,tumor necrosis factor α(TNF-α) and IL-12 were measured by adopting enzyme-linked immunosorbent assay.Results (1) The proportions of IL-35 +Breg and its expressions of IL-12p35,IL-27EBI3 and IL-10 in patients with acute KD were lower than those of healthy controls [IL-35 + Breg:(5.79 ± 2.60) ％ vs (12.65 ± 5.34) ％;F =19.23,9.70,14.30.7.08;all P ＜ 0.05],but they were significantly increased after intravenous immune globulin (IVIG) treatment [IL-35 + Breg:(10.52 ± 4.95) ％;all P ＜ 0.05].(2) The proportions of Treg and its transcriptional levels of IL-12p35 and IL-27 EBI3 were down-regulated during acute KD [Treg:(4.12 ± 1.51) ％ vs (8.06 ± 3.32) ％;F =19.70,17.69,38.22;all P ＜ 0.05],but were increased after therapy [Treg:(7.39 ± 2.85) ％;P ＜ 0.05].A positive correlation was found between the proportions of Treg and IL-35 + Breg during acute KD (r =0.69,P ＜ 0.05).Meanwhile,plasma concentrations of IL-35 and expression levels of IL-12Rβ2,IL-27Rα,pSTAT1 and pSTAT3 in CD19 + B cells were significantly down-regulated in children with acute KD,but they were increased after treatment(F =8.09,7.54,7.69,5.89,12.59,all P ＜ 0.05).(3) Compared with healthy controls,expressions of PD-L1 and CD169 on CD14 + cells and plasma concentrations of TNF-α and IL-12 were elevated during acute KD (F =24.94,16.53,34.71,19.51;all P ＜ 0.05).Expression levels of PD-1,CD43 and its downstream molecules (SHP-2,PTEN,Vav) in CD19 + B cells were down-regulated during acute KD (F =6.43,5.57,19.52,10.37,11.37;all P ＜ 0.05),and restored remarkably after therapy (all P ＜ 0.05).Conclusion Insufficiency of IL-35 + Breg and its expression of IL-35 may be the important factors contributing to immunological dysfunction in KD.

Objective To investigate the changes and significances of inducible IL-35-producing regulatory T cells(iTR35) in immunological pathogcnesis of Kawasaki disease (KD).Methods Forty-eight children with KD and 32 age-matched healthy children (healthy control group) consented to participate in this study.Flow cytometry was performed to evaluate the proportions of CD4+ FOXP3-IL-12p35+IL-27EBI3+iTR35 and CD4+CD25high FOXP3+regulatory T cells (Treg),and expression levels of associated molecules such as programmed death-ligand 1 (PD-L1),CD169,programmed death 1 (PD-1),CD43,IL-12p35,Epstein-Barr virus induced 3 (IL-27EBI3),glycoprotein 130(gp130),IL-12 receptor beta 2 (IL-12Rβ2),phosphated signal transducer and activator of transcription 1 (pSTAT1) and phosphated signal transducer and activator of transcription 4 (pSTAT4).Transcription levels of the Sre homology 2 domain-containing protein tyrosine phosphatase 2 (SHP-2),phosphatase and tensin homolog (PTEN),Vavl guanine nucleotide exchange factor(Vav) in CD4+T cells were determined by quantitative real-time PCR.Plasma concentrations of IL-35,IL-10,TNF-α and IL-12 were measured by enzyme-linked immunosorbent assay.Results (1) The proportions of iTR35 and its expressions of IL-12p35 and IL-27EBI3 in patients with acute KD dccreased remarkably[iTR35:(0.72±0.26) ‰ vs (1.65±0.43) ‰,P＜0.05],and restored after treatment [iTR35:(1.58±0.63) ‰ vs (0.72±0.26) ‰,P＜0.05].(2) The proportions of Treg and transcriptional levels of IL-12p35 and IL-27EBI3 were down-regulated during acute phase of KD [Treg:(3.26±1.21) ％ vs (7.26±2.86) ％,P＜0.05],and increased to some extent after therapy [Treg:(5.89±2.60)％ vs (3.26±1.21)％,P＜0.05].Meanwhile,plasma concentrations of IL-35 and IL-10,and expressions of gp130,IL-12Rβ2,pSTAT1 and pSTAT4 in iTR35 of patients with acute KD were found lower than those of the healthy control group (all P＜0.05),and increased after treatment (P＜0.05).Additionally,positive correlations were found between plasma concentrations of IL-35 and the proportion of iTR35 or its expressions of IL-12p35 and IL-27EBI3,respectively.(3) Expressions of PD-L1 and CD169 on CD14 + cells and plasma concentrations of TNF-α and IL-12 were elevated significantly during acute KD(all P＜0.05),as well as expression levels of the ligands (PD-1 and CD43) and its downstream molecules (SHP-2,PTEN,Vav) in CD4 + T cells were found to be lower in patients with acute KD (P＜0.05),and restored remarkably after therapy.Conclusion Insufficiency of iTR35 and its expression of IL-35 might be one of the important factors contributing to immunological dysfunction in KD.

Objective To investigate the clinical and biochemical metabolic features of 12 patients with systemic primary carnitine deficiency(CDSP) and to identify the SLC22A5 gene mutation types of the disease. Method The clinical and biochemical data were collected by retrospective analysis. DNA direct sequencing and multiplex ligation dependent probe amplification(MLPA)were applied for SLC22A5 gene analysis. Result Among 12 patients with CDSP, 3 cases had evident infection factors, 6 cases with convulsions, 5 cases manifested liver hypertrophy, 8 cases with hyperammonemia, and 9 cases showed myocardial damage. All CDSP patients were detected biallelic pathogenic mutation in SLC22A5 gene by direct sequencing. The gene types include IVS2+1G>T, c.3G>T(p.Met1Ile), c.760C>T(p.Arg254X), c.1400C>G(p.Ser467Cys), c.844dupc(p.Arg282fs), c.338G>A(p.Cys113Tyr), c.51C>G(p.Phe17Leu), c.659A>T(p.Glu220Val), and c.1365dupC(p.Thr456fs). c.659A>T(p.Glu220Val) and c.1365dupC(p.Thr456fs)are novel mutations. One female patient was maternal CDSP, her child had abnormal newborn screening. The allele frequency of c.760C>T(p.Arg254X) and c.1400C>G(p.Ser467Cys) were 37.5%(9/24)and 29.2%(7/24)respectively. The MLPA test results of all patients were negative. Conclusion The clinical manifestations are complex and various in patients with CDSP. Point and small InDel(insertions/deletions)mutation constitute the major alteration in SLC22A5 gene. c.1400C>G(p.Ser467Cys) might be another prevalence mutation type in Chinese CDSP patient.

Objective To investigate the effects of p300/CBP on histone acetylation of Foxp3 gene and its roles in the immunological pathogenesis of Kawasaki disease (KD).Methods Forty-six children with KD and twenty-eight age-matched health children were consented to participate in this study.Co-immunoprecipitation and real-time PCR were performed to detect Foxp3-associated acetylation levels of histone H4 and binding abilities of p300, CBP, pSmad3 (phosphorylated mothers against decapentaplegic homolog 3) and NF-AT (nuclear factor of activated T cells) with Foxp3 gene in CD4+ T cells.The percentages of CD4+CD25high Foxp3+ cells (Treg) and the expression of Foxp3, CTLA4 (cytotoxic T-lymphocyte-associated protein 4), p300, CBP, TGF-βRⅡ (transforming growth factor β receptor Ⅱ) and pLAT1 at protein level were analyzed by flow cytometry.Quantitative real-time PCR was used to measure the expression of Foxp3, IL-10, TGF-β, TGF-βRⅠ, Egr-1 (early growth response protein 1), RARα (retinoic acid receptor α) and PLCγ1 (phospholipase C-γ1) in Treg cells at mRNA level.Plasma concentrations of TGF-β and retinol acid (RA) were measured by enzyme-linked immunosorbent assay.Results (1) The percentages of Treg cells, levels of Foxp3 and molecules associated with suppressive function of Treg cells (TGF-β, IL-10 and CTLA4), acetylation levels of histone H4 associated with promoter, conserved non-coding DNA sequence 1 (CNS1) and CNS2 of Foxp3 gene decreased remarkably during acute KD (P<0.05), but were restored after IVIG therapy (P<0.05).Meanwhile, all of the aforementioned items in KD patients with coronary artery lesions (KD-CAL+) were lower than those without coronary artery lesions (KD-CAL-) (P<0.05).No significant differences in histone H4 acetylation associated with CNS3 were found among different groups (P>0.05).(2) The levels of p300 and CBP in Treg cells and their binding abilities with Foxp3 gene were down-regulated significantly during acute KD (P<0.05), but were restored to some extent after IVIG treatment (P<0.05).The Foxp3-associated histone acetylation was positively correlated with the expression of p300 and CBP at mRNA level during acute KD (r=0.65, 0.42, P<0.05).Furthermore, the expression of p300 and CBP and their binding abilities with Foxp3 gene in KD-CAL+ group were lower than those in KD-CAL-group (P<0.05).(3) Compared with healthy subjects, plasma concentrations of TGF-β and RA and the expression of TGF-βRⅠ/Ⅱ/Egr-1, RARα and pLAT1/PLCγ1 were down-regulated during acute KD (P<0.05);the binding abilities of pSmad3 and NFAT with Foxp3 gene were reduced remarkably in patients with acute KD (P<0.05).All the items mentioned above were restored after IVIG treatment (P<0.05).Moreover, the ten items aforementioned in KD-CAL+ group were lower than those in KD-CAL-group (P<0.05).(4) Higher acetylation levels of histone H4 associated with promoter, CNS1 and CNS2, and enhanced binding abilities of p300 and CBP with Foxp3 gene were found in CD4+ T cells isolated from patients with acute KD after co-stimulation with TGF-β, RA and anti-CD3/CD28 antibodies as compared with those in CD4+ T cells without stimulation (P<0.05).However, no statistical difference in the acetylation level of histone H4 associated with CNS3 was found between the two groups (P>0.05).Conclusion Hypoacetylation of histone H4 associated with Foxp3 gene caused by insufficient expression of p300/CBP and their impaired binding abilities might be involved with immune dysfunction in KD.IVIG therapy regulates the expression of p300/CBP and their binding abilities with Foxp3 gene through up-regulating TGF-β signal.

Objective To investigate the effects of SMYD3 and MLL5 on histone methylation of Transcription factor forkhead box protein 3 (Foxp3) gene and its roles in the immunological pathogenesis of Kawasaki disease (KD). Methods Forty-two children with KD and 26 age-matched healthy children were consented to participate in this study. Co-Immunoprec-ipitation and real-time polymerase chain reaction (PCR) was performed to determine Foxp3-associated histone methylation levels of H3K4me3 and H3K27me3, and binding levels of SMYD3 and MLL5 with Foxp3 gene in CD4+T cells. The proportion of CD4+CD25high Foxp3+cells (Treg) and protein levels of Foxp3, cytotoxic T lymphocyte associated antigen-4 (CTLA4), TGF-βRⅡand pSmad3 were analyzed by flow cytometry. Quantitative real-time PCR was used to evaluate levels of Foxp3, interleukin (IL)-10, GITR, TGF-βRⅠand RARαmRNA in CD4+T cells. Plasma concentrations of TGF-βand retinol acid (RA) were measured by enzyme-linked Immunosorbent assay. Independent-samples t-test was used as the statistical method in this study. Results ① The proportion of Treg, expression levels of Foxp3 and molecules associated with suppressive function of Treg cells(IL-10, GITR and CTLA4), and histone methylation levels of H3K4me3 associating with promoter, conserved non-coding DNA sequence (CNS) 1 and CNS2 of Foxp3 gene decreased remarkably during acute KD [Promoter:(5.4±1.8)%vs (9.1±2.2)%;CNS1:(2.6±0.9)% vs (3.8±1.1)%; CNS2: (2.4±0.8)% vs (4.2±1.0)%; t=5.50, 6.02, 9.56, 7.92, 7.97, 4.76, 7.73, 5.01, 8.66; P<0.05], and restored after intravenous immunoglobulins (IVIG) therapy [Promoter: (7.2 ±2.1)% vs (5.4 ±1.8)%; CNS1:(3.6±1.4)% vs (2.6±0.9)%; CNS2: (3.6±1.4)% vs (2.4±0.8)%; t=5.56, 4.59, 7.01, 6.04, 5.89, 4.83, 4.45, 4.00, 5.12; P<0.05]. Meanwhile, the nine former items in KD patients with coronary artery lesions (KD-CAL+) were lower than those without coronary artery lesions (KD-CAL-) [Promoter: (4.11±1.45)% vs (6.16±1.93)%; CNS1:(1.99±0.87)%vs (2.96±1.10)%;CNS2: (1.75±0.63)%vs (2.72±1.16)%;t=6.28, 3.24, 4.56, 3.69, 3.38, 4.40, 3.65, 3.00, 3.51; P<0.05]. No significant difference of H3K4me3 associated with CNS3 and H3K27me3 were found among the groups (t=1.03, 0.91, 1.48 and 0.79, 0.82, 1.53; P>0.05). ② Binding levels of SMYD3 and MLL5 with Foxp3 gene in CD4+T cells were down-regulated significantly during acute KD (t=6.63, 6.15; P<0.05), and restored to some extent after IVIG treatment (t=5.36, 4.56; P<0.05). Positive correlations between binding levels of SMYD3 and MLL5 and expression level of Foxp3 mRNA were detected in patients with acute KD (r=0.62、0.45, P<0.05). Furthermore, Binding levels of SMYD3 and MLL5 with Foxp3 gene in KD-CAL+group were lower than those in KD-CAL- group (t=4.11, 4.31; P<0.05). ③ Compared with healthy controls, plasma concentration of TGF-β and RA, and expressions of TGF-βRⅡ, TGF-βRⅠ, pSmad3 and RARα were down-regulated during acute KD (t=11.54, 12.81, 7.43, 16.10, 8.25, 12.06; P<0.05), and elevated remarkably after IVIG treatment (t=8.40, 6.24, 5.94, 11.78, 6.27, 8.30; P<0.05). Simultaneously, all the items aforementioned in KD-CAL+ group were found to be lower than those in KD-CAL-group (t=3.58, 3.30, 3.82, 5.27, 4.71, 3.78; P<0.05). Conclusion Hypomethylation of H3K4me3 associated with Foxp3 gene caused by insufficient binding levels of SMYD3/MLL5 may be involved with immune dysfunction in Kawasaki disease.

Objective To investigate the changes and significances of IL-17-associated histone methylation in the acute phase of Kawasaki disease (KD). Methods Forty-two children with KD and 28 age-matched healthy children were recruited in this study. Co-immunoprecipitation and real-time PCR were performed to detect the IL-17-associated histone methylation in CD4+ T cells. The percentages of CD4+IL-17+ T cells (Th17) and the expression of IL-17 and pSTAT3 at protein level were analyzed by flow cytome-try. Quantitative real-time PCR was used to measure the expression of IL-17, IL-6Rα, gp130, IL-23R, IL-23Rβ1, ETV5, SOCS1, SOCS3, TLR4, MyD88/TRIF, TNFR1 and RIP1 at mRNA level and the expres-sion of miR155 in CD4+ T cells. The levels of IL-6, IL-23 and TNF-αin plasma samples were measured by enzyme-linked immunosorbent assay. Results (1) The children with acute KD showed increased percenta-ges of Th17 cells and enhanced expression of IL-17 and H3K4me3, but inhibited expression of H3K27me3 [H3K4me3:(3.79±1. 45)% vs (1. 93±0. 31)%, H3K27me3: (54. 51±13. 60)% vs (73. 96± 22. 32)%;P<0. 05]. Moreover, the three former indexes in KD patients complicated with coronary artery lesions ( KD-CAL+) were higher than those in KD patients without coronary artery lesions ( KD-CAL-) , while the levels of H3K27me3 in KD-CAL+ group were lower than those in KD-CAL- group [ H3K4me3:(5. 11±1. 68)% vs (2. 98±0. 99)%, H3K27me3:(45. 02±14. 83)% vs (60. 35±12. 51)%;P<0. 05]. A positive correlation was observed between the ratio of H3K4me3/H3K27me3 and IL-17 at transcriptional level in patients with acute KD (r=0. 69, P<0. 05). Treatment with intravenous immunoglobulin (IVIG) restored Th17 cells, expression of IL-17 and methylation levels of H3K4me3 and H3K27me3 to normal levels [H3K4me3:(2. 44 ± 0. 77)% vs (3. 79 ± 1. 45)%, H3K27me3: (66. 52 ± 15. 73)% vs (54. 51 ± 13. 60)%;P<0. 05]. (2) The expressions of pSTAT3, ETV5 and miR155 increased significantly in pa-tients with acute KD, while the expressions of negative regulators of pSTAT3 ( SOCS1 and SOCS3 ) were down-regulated. The expressions of pSTAT3, ETV5 and miR155 in KD-CAL+ group were higher than those in KD-CAL- group (P<0. 05), while the levels of SOCS1 and SOCS3 in KD-CAL+ group were lower than those in KD-CAL- group (P<0. 05). IVIG therapy restored the indexes mentioned above to some extent (P<0. 05). (3) Compared with the healthy subjects, the levels of inflammatory cytokines (IL-6, IL-23 and TNF-α) in plasma and the expressions of surface receptors (TLR4, IL-6Rα/gp130, IL-23R/IL-23Rβ1 and TNFR1) and its downstream adaptors (MyD88, TRIF, RIP1) in CD4+T cells were up-regulated in patients with acute KD (P<0. 05), but were down-regulated significantly after IVIG treatment (P<0. 05). Moreo-ver, all of the indexes mentioned above in KD-CAL+ group were found to be higher than those in KD-CAL-group (P<0. 05). Conclusion Aberrant patterns of IL-17-associated histone methylation might be related to the immune dysfunction in patients with KD.