Ulcerative Colitis (UC) has been reported to be related to Porphyromonas gingivalis (P. gingivalis). Porphyromonas gingivalis peptidylarginine deiminase (PPAD), a virulence factor released by P. gingivalis, is known to induce inflammatory responses. To explore the pathological relationships between PPAD and UC, we used homologous recombination technology to construct a P. gingivalis strain in which the PPAD gene was deleted (Δppad) and a Δppad strain in which the PPAD gene was restored (comΔppad). C57BL/6 mice were orally gavaged with saline, P. gingivalis, Δppad, or comΔppad twice a week for the entire 40 days (days 0-40), and then, UC was induced by dextran sodium sulfate (DSS) solution for 10 days (days 31-40). P. gingivalis and comΔppad exacerbated DDS-induced colitis, which was determined by assessing the parameters of colon length, disease activity index, and histological activity index, but Δppad failed to exacerbate DDS-induced colitis. Flow cytometry and ELISA revealed that compared with Δppad, P. gingivalis, and comΔppad increased T helper 17 (Th17) cell numbers and interleukin (IL)-17 production but decreased regulatory T cells (Tregs) numbers and IL-10 production in the spleens of mice with UC. We also cocultured P. gingivalis, Δppad, or comΔppad with T lymphocytes in vitro and found that P. gingivalis and comΔppad significantly increased Th17 cell numbers and decreased Treg cell numbers. Immunofluorescence staining of colon tissue paraffin sections also confirmed these results. The results suggested that P. gingivalis exacerbated the severity of UC in part via PPAD.
Animals ; Colitis, Ulcerative/microbiology* ; Mice ; Mice, Inbred C57BL ; Porphyromonas gingivalis/pathogenicity* ; Protein-Arginine Deiminases ; Virulence Factors

OBJECTIVETo assess the association between genetic polymorphisms of 7 SNPs in PTPN22 and PADI4 genes and susceptibility to rheumatoid arthritis in Yunnan.

METHODSA case-control study was carried out on 192 patients of rheumatoid arthritis and 288 healthy controls. Genotypes of rs33996649 and 1858 loci within PTPN22 gene, and rs11203366 and rs874881 loci within PADI4 gene were determined with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Genotypes of rs1635579, rs2428736 and rs2240340 in PADI4 gene were determined with pyrosequencing.

RESULTSThe frequencies of alleles and genotypes of rs2240340 locus in PADI4 gene showed a significant difference between rheumatoid arthritis and controls in Yunnan population (P U+003C 0.05).

CONCLUSIONOur results suggested that rs2240340 in PADI4 gene is associated with susceptibility to rheumatoid arthritis in Yunnan.

Alleles ; Arthritis, Rheumatoid ; genetics ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; China ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Hydrolases ; genetics ; Male ; Polymorphism, Single Nucleotide ; Protein Tyrosine Phosphatase, Non-Receptor Type 22 ; genetics ; Protein-Arginine Deiminases

OBJECTIVETo study the expression level of peptidylarginine deiminase 4 (PADI4) and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in the synovium of rat model of collagen-induced arthritis, and to explore their possible therapeutic role in rheumatoid arthritis.

METHODSThirty-two female Wistar rats weighing 100±20 g were randomly assigned into 3-week collagen-induced arthritis (CIA) model group (n=8), 4-week CIA model group (n=8), 6-week CIA model group (n=8), and the control group (n=8). The body weight changes of each group were recorded. The expression levels of PADI4 and PTPN22 were detected and compared by the methods of immunohistochemical staining and Western blot.

RESULTSArthritis of rat began to form 14 days after sensitization and the joint swelling reached peak at 28 days. The weights of the rats slowly grew both in CIA model groups and the control group. Immunohistochemical staining results showed that the positive expression of PADI4 and PTPN22 was mainly located in cartilage peripheral mononuclear cells, the cytoplasm of infiltrated cells, and bone marrow cavity. There were significant differences in the optical density of PADI4 and PTPN22 among CIA model groups and the control group (PADI4, 0.2898±0.012, 0.2982±0.022, 0.2974±0.031, 0.2530±0.013 in 3-week CIA model, 4-week CIA model, 6-week CIA model and control groups; PTPN22, 0.2723±0.004, 0.2781±0.010, 0.2767±0.008, 0.2422±0.019; all P <0.05). The expression bands of PADI4 were observed in Western blot 3 weeks after initial immunization, the thickest in the 4th week, and decreased in the 6th week. The expression bands of PTPN2 were observed at all the time points, with no obvious time-dependent trend.

CONCLUSIONSPADI4 and PTPN22 are obviously correlated with CIA in rat model. PADI4 is expressed at early stage of the disease, while the expression of PTPN22 sustains throughout the course.

Animals ; Arthritis, Experimental ; enzymology ; metabolism ; Blotting, Western ; Collagen ; administration & dosage ; Female ; Hydrolases ; metabolism ; Immunohistochemistry ; Protein Tyrosine Phosphatase, Non-Receptor Type 22 ; metabolism ; Protein-Arginine Deiminases ; Rats ; Rats, Wistar ; Synovial Membrane ; enzymology ; metabolism

OBJECTIVETo explore the association of the expressions of human leukocyte antigen (HLA)-DR4, peptidyl arginine deiminase type4(PAD4), and signal transducer and activator of transcription 4 (STAT4) in the peripheral blood with the disease activity in patients with rheumatoid arthritis (RA).

METHODSTwenty-four RA patients in active stage (DAS28 score>or=2.6) and 14 RA patients in remission stage (DAS28 score<2.6) were enrolled in this study, with 12 healthy volunteers as the control. The QuantiGene Plex method was used to measure the expression level of HLA-DR4, PAD4, and STAT4 mRNA, and the relationship between the expressions of these genes and the DAS28 score, levels of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) and rheumatoid factor (RF) was analyzed.

RESULTSThe expressions of HLA-DR4, PAD4, and STAT4 were significantly higher in RA patients than in the healthy controls (P<0.05). The level of HLA-DR4 mRNA in the two RA groups showed no significant difference, but was significantly higher than that in the healthy controls. HLA-DR4 expression was not found to correlated to DAS28 score, anti-CCP antibody level or RF in the RA patients. The expressions of PAD4 and STAT4 were significantly different between the two RA groups (P<0.05). In the RA patients, PAD4 mRNA expression was positively correlated to DAS28 and anti-CCP antibody level (P<0.05), and STAT4 expression showed positive correlations to DAS28 and RF levels (P<0.05).

CONCLUSIONHLA-DR4, PAD4 and STAT4 are overexpressed in RA patients and may be involved in the pathogenesis of RA. The expressions of PAD4 and STAT4, but not HLA-DR4, are closely related to the disease activity of RA. Detection of peripheral blood PAD4 and STAT4 expressions can be helpful for evaluating the disease activity of RA.

Adult ; Arthritis, Rheumatoid ; blood ; Female ; HLA-DR4 Antigen ; blood ; genetics ; metabolism ; Humans ; Hydrolases ; blood ; genetics ; metabolism ; Male ; Middle Aged ; Protein-Arginine Deiminases ; RNA, Messenger ; genetics ; metabolism ; STAT4 Transcription Factor ; blood ; genetics ; metabolism

OBJECTIVETo investigate the association of single nucleotide polymorphisms (SNPs) of the peptidylarginine deiminase IV (PADI4) and HLA-DRB1 shared epitope (SE) alleles with rheumatoid arthritis(RA) in a Chinese population.

METHODSFour exonic SNPs of the PADI4 gene (PADI 4_89*A/G, PADI 4_90*C/T, PADI 4_92*C/G and PADI 4_104*C/T) were genotyped in 67 unrelated patients with RA and 81 healthy controls, using cDNA sequencing and T vector cloning. HLA-DRB 1*01, *04 and *10 subtypes were determined by polymerase chain reaction with sequence specific primers (PCR-SSP).

RESULTSThe distributions of the 4 SNPs were different in the two groups, and increased RA susceptibility was significantly associated with the minor alleles of PADI 4_89*G (P was 0.023), PADI 4_90*T (P was 0.004), PADI 4_104*T (P was 0.003), and the haplotypes carrying the 4 minor alleles (P was 0.008). HLA-DRB1 SE alleles are composed of HLA-DRB 1*0101, *0102, *0401, *0404, *0405, *0408, *0409, *0410 and *1001. Individuals carrying the SE alleles were associated with increased RA susceptibility (P was 0.002). Individuals carrying both the SE alleles and minor alleles of the 4 SNPs were more susceptible to RA than individuals carrying neither the minor SNP alleles nor the SE alleles.

CONCLUSIONThe PADI4 SNPs and haplotypes are associated with RA susceptibility in Chinese. HLA-DRB1 shared epitope is also an important risky factor for RA. There may exist certain synergistic effect between the PADI4 minor alleles and the HLA-DRB1 shared epitope.

Adult ; Aged ; Aged, 80 and over ; Alleles ; Arthritis, Rheumatoid ; genetics ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Epitopes ; genetics ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; HLA-DR Antigens ; genetics ; HLA-DRB1 Chains ; Humans ; Hydrolases ; genetics ; Male ; Middle Aged ; Phenotype ; Polymorphism, Single Nucleotide ; Protein-Arginine Deiminases