[Changes in expression of PYCARD gene and its transcript variant mRNA in peripheral blood mononuclear cells of patients with primary gout].

OBJECTIVE: To determine the expression level and role of PYCARD [PYRIN-PAAD-DAPIN domain (PYD) and a C-terminal caspase recruitment domain (CARD), PYCARD] gene and its transcript variant mRNA in peripheral blood mononuclear cells (PBMCs) of patients with primary gout (PG). METHODS: PYCARD gene and its transcript variant mRNA were measured using reverse transcription-polymerase chain reaction (RT-PCR) in PBMCs. The expression of PYCARD gene and PYCARD-1,-2 mRNA in PBMCs was compared between the patients with acute phase PG (APPG) (n=44), non-acute phase PG (NAPPG) (n= 51) and healthy controls (HC) (n=87). PYCARD and NF-kappaB (p105/p50) protein expressions were measured using Western blot in the PBMCs of participants in the PG and HC groups. Routine blood tests and blood uric acid test were undertaken in all participants. Differences in the indicators were examined among the three groups. Correlations between the expression of PYCARD gene and PYCARD-1,-2 mRNA and other indicators were analyzed. RESULTS: The expression level of PYCARD gene, PYCARD-1,-2 mRNA was significantly higher in the APPG and NAPPG group than in the HC group (P<0.01). The NAPPG group had significantly higher levels of PYCARD gene transcript variant 2x mRNA and 2y mRNA in the HC and APPG groups (P<0.05). The expression of PYCARD and NF-kappaB (p105/p50) protein was significantly higher in the PG group compared with the HC group [(4.900 +/- 1.324) vs. (3.975 +/- 0.210) and (0.263 +/- 0.106) vs. (0.127 +/- 0.008), respectively P<0.05]. The expression level of PYCARD-2 mRNA and granulocyte were positively correlated in the NAPPG group. CONCLUSION: Abnormal expression of PYCARD gene and its transcript variant and PYCARD protein in PG patients suggests that PYCARD gene and its transcript variant may play an important role in regulating the inflammatory response of PG patients.

[Effects of danshen injection on the proliferation of rheumatoid arthritis fibroblast-like synoviocytes cultured with human serum].

OBJECTIVE: To investigate the effects of Danshen Injection (DSI) on the proliferation of rheumatoid arthritis fibroblast-like synoviocytes (RA FLSs) cultured in RA patients' serum. METHODS: The RA FLSs harvested from RA patients' synovial fluid were primarily cultured by routines. The cells were cultured with 10% inactivated human serum (the healthy human serum and the RA patients' serum) for 24 h. Then DSI at the final concentration of 0. 4 mg/mL was added in the cells for further 24 h culture. By taking 10% fetal calf serum as the control, the morphological changes were observed under optical microscope. The proliferation was analyzed by MTT. The apoptosis was detected by flow cytometry. The total RNA was extracted and reverse transcription was performed. The Bax mRNA expression was detected by fluorescent quantitative PCR. RESULTS: (1) After human serum was added in the healthy human serum and RA patients' serum, cells could grow adhering to the wall. Compared with the fetal calf serum group (FCS), the cell density was higher in the healthy human serum group than in the fetal calf serum group, with no obvious morphological changes. (2) MTT results showed that, compared with the fetal calf serum group, the absorbance value (OD) obviously increased in the healthy human serum group and the RA patients' serum group, showing statistical difference (P <0.01). After adding DSI at the final concentration of 0.4 mg/mL, cells from different serums were inhibited to various degrees (with OD significantly decreased, P <0.05). The OD value significantly increased more in the healthy human serum group and the RA patients' serum group than in the fetal calf serum group, showing statistical difference (P <0.01). There was statistical difference between the healthy human serum group and the RA patients' serum group (P <0.01). (3) The apoptosis rate in the RA patients' serum group obviously decreased with statistical difference, when compared with the Salvia miltiorrhiza free fetal calf serum group (P >0. 01). The apoptosis rate in the fetal calf serum group and the RA patients' serum group significantly increased after adding 0.4 mg/mL Salvia miltiorrhiza, showing statistical difference when compared with the Salvia miltiorrhiza free fetal calf serum group and the Salvia miltiorrhiza free RA patients' serum group (P <0.05). The FLSs were effected by 0.4 mg/mL Salvia miltiorrhiza, the apoptosis rate significantly decreased in the healthy human serum group and the RA patients' serum group, showing statistical difference when compared with the fetal calf serum group (P <0. 05, P <0.01). (4) The expression of Bax gene significantly increased in the RA patients' serum group and the fetal calf serum group after action of 0.4 mg/mL Salvia miltiorrhiza, showing statistical difference (P <0. 01). When 0.4 mg/mL Salvia miltiorrhiza was added, the expression of Bax mRNA obviously increased in the healthy human serum group and the RA patients' serum group, showing statistical difference when compared with the fetal calf serum group (P <0.01). CONCLUSIONS: (1) Although healthy human serum can be favorable to the growth of RA FLSs, the fetal calf serum could reflect the actual results better in the cyto biological research on specific diseases (if there is no serum from patients with corresponding disease). (2) DSI could inhibit the proliferation of RA FLSs through promoting their apoptosis.

Altered expression of TPP1 in fibroblast-like synovial cells might be involved in the pathogenesis of rheumatoid arthritis.

We undertook this study to determine whether the altered expression of telomeric proteins TPP1 and POT1 in fibroblast-like synovial cells (FLS) could provide insights into the pathogenesis of rheumatoid arthritis (RA). FLS were isolated from patients with RA, osteoarthritis (OA) and traumatic joint disease, and cultured in vitro. TPP1 and POT1 mRNA level of FLS were measured using real-time quantitative polymerase chain reaction (RT-qPCR) in 42 RA, 23 OA and 13 healthy cases. Immunofluorescence staining and Western blot were used to detect the expression of TPP1 and POT1 protein. Expression of TPP1 and POT1 mRNA was significantly reduced in RA cases (P < 0.001, respectively), and no significant difference was observed between OA and healthy cases (P > 0.05, respectively). Confocal microscopy images showed TPP1 and POT1 proteins mainly located in nucleus of FLS. Western blot demonstrated that TPP1 protein level was significantly reduced in RA cases (P < 0.001), and POT1 protein expression was not statistical significance among RA, OA patients and healthy cases (P > 0.05). Significant negative correlation was observed between level of TPP1 mRNA and titers of anti-CCP antibody (P < 0.001), RF (P < 0.01). Altered expression of TPP1 might contribute to persistent proliferation of FLS in RA, further study on functions of telomeric proteins in RA would be needed.

[Construction of recombinant E. coli-L. interrogans shuttle plasmid pGKINVA and screening recombinant leptospira strains].

OBJECTIVE: To further investigate pathogenic function of invA in Leptospira, recombinant L. biflexa-Escherichia coli shuttle vector pGKINVA was constructed, and electropored into L. biflexa strain Patoc I . METHODS: The invA gene was cloned into shuttle vector pGKble24 to construct a recombinant L. biflexa-Escherichia coli shuttle vector pGKINVA. The recombinant vectors were electropored into L. biflexa serovar Patoc strain Patoc I . RESULTS: A 558 bp invA was amplified from L. interrogans serovars Lai strain 017 and ligated with Aat II and Xma I digested pGKble24. After screening by kanamycin and blue/white color, the recombinant pGKINVA was obtained and sequenced. Subsequently, the recombinant pGKINVA was electropored into L. biflexa strain Patoc I. The selected mutants were identified by PCR. CONCLUSION: Recombinant L. biflexa-Escherichia coli shuttle vector with invA insert was constructed and two strains of pGKINVA transformed Leptospira were obtained. These pGKINVA transformed Leptospira strains would provid an experimental model to investigate potential pathogenic functions of invA in vivo.

[Expression of the fusion protein CFP10-ESAT6 of Mycobacterium tuberculosis and the study of its immunogenicity].

OBJECTIVE: To express a recombinant fusion protein CFP10-ESAT6 of Mycobacterium tuberculosis, and obtain the polyclonal antibodies of this fusion protein by immune rabbit. METHODS: The 630 bp cfpl0-esat6 fusion gene fragments were amplified from the genomic DNA of a Mycobacterium tuberculosis reference strain H37Rv and inserted into the expression plasmid pET32a (+) to generate the recombinant plasmid pET-cfp10-esat6. The recombinat expression plasmid was transformed into E. coli BL21 (DE3). The fused protein CFP10-ESAT6 with His-tag was expressed after inducing with IPTG and purified with affinity chromatography. This protein was used to immune the rabbit to obtained the polyclonal antibodies, and been analyzed with Western-blot and ELISA. RESULTS: The recombinant plasmid pET-cfp10-esat6 was success fully constructed, the recombinant fusion protein CFP10-ESAT6 could be expressed at relatively high levels, and the polyclonal antibodies of fusion protein were obtained. CONCLUSION: The successful construction and expression of the recombinant fusion protein CFP10-ESAT6 and the obtained polyclonal antibodies will be very helpful for the development of new anti-tuberculosis vaccine and the clinical serologic diagnosis.

[Prokaryotic expression and characterization of the Rv2994 gene from Mycobacterium tuberculosis].

OBJECTIVE: To construct a prokaryotic expression vector bearing Rv2994 gene from Mycobacterium tuberculosis and provide materials for investigating the function of the gene. METHODS: The Rv2994 gene was amplified by Polymerase Chain Reaction from Mycobacterium tuberculosis H37Rv strain and cloned into prokaryotic expression vector pGEX-1lamdaXT. The recombinant plasmid pGEX-2994 was sequenced and transformed into E. coli JM109 to be induced with IPTG and expressed the 73kDa fusion protein GST-Rv2994. It's antigenicity was confirmed by Western blotting. The expression product was purified and immunized the new Zealand rabbits. RESULTS: The Rv2994 gene was amplified accurately from the genome DNA of H37Rv. A recombinant fused expression vector pGEX-Rv2994 was constructed and GST-Rv2994 protein was purifiel to immunize New Zealand rabbit. CONCLUSION: The prokaryotic expression vector pGEX-2994 was constructed, and the 73kDa fusion protein GST-Rv2994 was expressed and purified successfully. It provided the basis for the further study of the Rv2994 gene.

[Study on the gene mutation of quinolone-resistant Mycobacterium tuberculosis isolated from Sichuan Province].

OBJECTIVE: To investigate the molecular mechanism of quinolone-resistance of M. tuberculosis and characterize the gene mutation in Sichuan Province. METHODS: Susceptibility of the clinical isolates to quinolones (ofloxacin, ciprofloxacin and sparfloxacin) was tested by the absolute concentration method. GyrA gene quinolone reasistance-determining region (QRDR) mutations M. tuberculosis were detected with PCR-SSCP and DNA sequencing. RESULTS: Of 68 clinical isolates of M. tuberculosis, 25 high-resistant, 11 low-resistant and 10 sensitive isolates were noted to have abnormal gyrA SSCP profile and different gyrA sequences from the standard strain H37Rv, and 14 sensitive and 8 low-resistant isolates were found with no mutation of gyrA gene. DNA sequencing unveiled Ser-->Thr mutation at codon 95, Asp-->Gly at codon 94, Ala-->Val at codon 90, and Ala-->Val at codon 83. CONCLUSION: This study confirmed the strong correlation between the quinolone-resistance and the mutation of gyrA gene, which might be a major molecular mechanism of quinolone-resistance in M. tuberculosis. The types of mutations exhibit no difference between Sichuan Province and other areas in China.