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Objective This study was performed to investigate the infection of Lipopolysaccharide(LPS) and its downstream cytokine High-mobility Group Box 1(HMGB1)on the transcriptional regulation of macrophage polarization.Methods The murine macrophage cell line RAW246.7 was stimulated with LPS and HMGB1 respec-tively.The levels of M1 macrophage related mRNA(NOS2,TNF-α,IL-6)and M2 related mRNA(ARG-1,RELM-α)were determined by Q-PCR.Results The expression of M1 macrophage related mRNA(NOS2,IL-6,TNF-α) was significantly upregulated(P<0.01),while the M2 macrophage related mRNA(ARG-1,RELM-α)was down-regulated(P > 0.05)after the stimulation of LPS. Both the M1 and M2 related markers were upregulated at the mRNA level in HMGB1 stimulate group,and the upregulation of NOS2,TNF-α and RELM-α was statistically sig-nificant(P<0.01).Conclusions LPS induces the M1 polarization of murine macrophage,which involved in the inflammation reaction.HMGB1,as the downstream cytokine of LPS signaling,induces both M1/M2 polarization of murine macrophage. It′s inferred that HMGB1 intensifies periodontal inflammatory responses and,at the same time,involves the negative feedback mechanism in the responses to tissue remodeling.
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Objective To study the effects of MF59 in combination with heat-killed BCG ( hBCG) as adjuvant on the immunogenicity of Mycobacterium tuberculosis fusion protein PstS1-LEP.Methods BALB/c mice were divided into six groups from group 1 through group 6.They were immunized with PstS1-LEP+MF59 ( group 1 ) , PstS1-LEP+MF59/hBCG ( group 2 ) , PstS1-LEP+hBCG ( group 3 ) , MF59 ( group 4 ) , PstS1-LEP (group 5) and hBCG (group 6) for three times at intervals of two weeks , respectively.The mice were sac-rificed two weeks after the last immunization .The serum samples were collected for antibodies detection .The splenic lymphocytes and peritoneal macrophages were isolated and cultured with PstS 1-LEP.Indirect ELISA and sandwich ELISA were used to detect PstS 1-LEP-specific antibodies and cytokines in the supernatants of culture , respectively.Results The level of IFN-γ, IL-1β, IgG, IgG1 and IgG2a in group 1 were higher than those in groups 4, 5 and 6 (P<0.05).The level of IL-2 and IL-4 in group 1 were higher than those in groups 4 and 6 (P<0.05).The level of IFN-γ, IL-1β, IL-12, IgG, IgG1 and IgG2a in group 2 were higher than those in groups 4, 5 and 6 (P<0.05).The level of IL-2 was higher in group 2 than that in groups 4 and 6 (P<0.05). The level of IL-4 in group 3 was higher than that in group 4 ( P=0.05 ) .The level of IL-1βin group 3 were higher than that in groups 4 and 5 ( P<0.05 ) .The level of IgG was higher in group 3 than that in groups 4 and 6 (P<0.05).IgG1 level in group C was up-regulated in comparison with that in groups 4, 5 and 6 (P<0.05 ) .Conclusion hBCG as PstS1-LEP adjuvant induces a shift towards Th 2-type immune response , while MF59 induces Th1/Th2-type immune response.The combination of MF59 and hBCG inhibits the secretion of IL-4 by spleen lymphocytes , but enhances the secretion of IL-12 by macrophage .
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Objective To evaluate the potential value of IgG antibodies against recombinant PPE65 protein (rPPE65) of Mycobacterium tuberculosis in serodiagnosis of tuberculosis.Methods The gene encoding PPE65 protein of M.tuberculosis was cloned into the PET-28a vector and then expressed in Escherichia coli.The rPPE65 was purified with Ni-NTA affinity and ion exchange chromatography.After dialysis renaturation, the concentration of rPPE65 was determined using Lowry assay.ELISA was used to detect the levels of specific IgG against rPPE65 and recombinant PstS1 protein (rPstS1) in sera from 144 patients with pulmonary tuberculosis (PTB patients), 144 health controls, and 56 patients with non-tuberculosis pulmonary diseases.ROC curves were used to determine cut-off values with the results of IgG antibodies against rPPE65 and rPstS1 for 144 PTB patients and 97 controls with negative PPD skin test.The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of rPPE65 and the combination of rPPE65 and rPstS1 were counted.Results The PPE65 protein of M.tuberculosis was successfully expressed in E.coli. The purity and concentration of rPPE65 were 95% and 0.5 mg/ml, respectively.ROC analysis showed that the cut-off of ELISA using rPPE65 was 0.64.The sensitivity, specificity, PPV, NPV, and accuracy of rPPE65 were 34.7%(50/144), 93.5%(187/200), 79.4%(50/63), 66.5%(187/287), and 68.9%(237/344), respectively.The sensitivity, specificity, PPV, NPV, and accuracy of the combination of rPPE65 and rPstS1 were 59.0%, 91.0%, 82.5%, 75.5%, 77.6%, respectively.Conclusions The rPPE65 of M.tuberculosis appears to be a candidate antigen for serodiagnosis of tuberculosis.Detection of IgG antibodies against the combination of rPPE65 and rPstS1 can increase the sensitivity of serological test for tuberculosis.
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Objective To evaluate the frequency of pncA gene mutations in pyrazinamide-resistant (PZA-resistant)Mycobacterium tuberculosis(M.TB)isolates.Methods The isolates were tested for PZA susceptibility with absolute concentration method.The pncA gene was amplified and the products were cloned into T-vector,followed with sequencing.Results In all the 36 M.TB isolates,there were 25 PZA-resistant strains and 11 PZA-susceptible strains.Mutations of the pncA gene were found in 10 PZA-resistant isolates,four of which belonging to high PZA-resistant strains.The wild type pncA sequence was present in 3 PZA-susceptible strains, synonymous mutations of pncA gene were detected in two PZA-susceptible strains.Additionally,11 PZA-resistant strains and 2 PZA-susceptible ones showed putative regulatory mutations in the upsteam of pncA gene.Condusions The mutation of the pncA gene can cause the PZA resistance.However.there ale other drug resistance mechanism except this mutation.