Serum Macrophage Migration Inhibitory Factor as a Biomarker of Active Pulmonary Tuberculosis.

BACKGROUND: Macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine with chemokine-like functions, has been shown to play a central role in several acute and chronic inflammatory diseases. However, limited information is available regarding the use of MIF as an inflammatory pathway marker in patients with tuberculosis. This study aimed to investigate the association of MIF with IFN-γ and TNF-α in active pulmonary tuberculosis (APTB) following anti-tuberculosis treatment. METHODS: The MIF, TNF-α, and IFN-γ serum levels were determined in 47 patients with APTB by cytokine-specific ELISA at four phases: prior to anti-tuberculosis drug treatment (baseline), and following 2, 4, and 6 months of treatment. In addition, we measured the MIF, TNF-α, and IFN-γ serum levels in 50 health controls. RESULTS: MIF serum levels were significantly elevated (P<0.05) in patients with APTB prior to treatment compared with that in control subjects, and TNF-α ≥449.7 pg/mL was associated with high MIF levels (≥13.1 ng/mL). MIF levels were significantly reduced (P<0.01) following 2, 4, and 6 months of treatment, with variations in TNF-α and IFN-γ serum levels. MIF levels were positively correlated with the paired TNF-α level at baseline (r=0.1103, P=0.0316) and following 6 months of treatment (r=0.09569, P=0.0364). CONCLUSIONS: A reduction in the MIF serum levels in patients with APTB following anti-tuberculosis treatment may positively affect host immune protection against Mycobacterium tuberculosis infection. Thus, serum MIF levels may constitute a useful marker for assessing therapy effectiveness in patients with APTB.

Functional polymorphisms in the gene encoding macrophage migration inhibitory factor (MIF) are associated with active pulmonary tuberculosis.

OBJECTIVE: The role of the cytokine, macrophage migration inhibition factor (MIF) was assessed in tuberculosis. This case-control study investigated whether commonly occurring functional MIF polymorphisms are associated with active tuberculosis as well as with serum levels of MIF, IFN-γ and TNF-α. METHODS: Two MIF promoter polymorphisms, a functional -794 CATT5-8 microsatellite repeat (rs5844572) and a -173G/C single-nucleotide polymorphism (rs755622), were analysed by PCR and PCR-RFLP, respectively, in 47 patients and 50 healthy subjects. The mRNA level of MIF was performed by real-time PCR (RT-PCR), and MIF, IFN-γ and TNF-α serum levels were determined by ELISA. RESULTS: A significant increase of MIF mRNA expression and MIF protein level were found in patients compared to healthy controls. Meanwhile, the increase of IFN-γ and TNF-α serum levels were confirmed. According to the profile of genetic model, a significant association was found of genotypes carrying the -794 CATT 7 or 8 and -173 C risk alleles with susceptibility to active tuberculosis and with a significant increase of MIF, IFN-γ and TNF-α. CONCLUSIONS: These data suggested a distinct genetic and immunopathogenic basis for tuberculosis at the MIF locus. Serum MIF, IFN-γ and TNF-α profiles distinguish tuberculosis from the more inflammatory phenotype and may play a role in pathogenesis and as biomarkers of active tuberculosis.

T helper cell dysregulation with hepatitis B and rebalance with glucocorticoids.

AIM: To investigate T helper 17/regulatory T cell alterations in early severe hepatitis B and the effect of glucocorticoids. METHODS: The study included 20 patients in the early stage of severe hepatitis B (SHB) and 11 healthy controls. All patients had elevated T helper 17 (Th17) levels, decreased regulatory T (Treg) cell levels, and significant Th17/Treg ratios. RESULTS: After glucocorticoid treatment, 16 patients showed improvement with significant decreases in Th17 levels, increases in Treg, and rebalanced Th17/Treg ratios. The four patients who showed no improvement had increases in both Th17 and Treg levels and an even higher Th17/Treg ratio than before. CONCLUSION: Glucocorticoid treatment can rectify Th17/Treg dysregulation in patients with SHB.

[Cell death of THP-1 induced by puried Rv3671c protein of tuberculosis and the detection of TNF-α and IL-1ß in Mycobacterium tuberculosis].

OBJECTIVE: To assess the response in THP-1 treated with Rv3671c protein in Mycobacterium tuberculosis (M.tuberculosis). METHODS: The gene encoding Rv3671c protein of M.tuberculosis was cloned into pET-28a vector and then expressed in Escherichia coli. The Rv3671c was purified with Ni-NTA affinity and ion exchange chromatography. The detection of protein concentration was by Lowry method.THP-1 cell was stimulated with Rv3671c protein and cells were analyzed by Hochest staining under fluorescence microscopy to assay cell death (apoptosis and necrosis). TNF-α and IL-1ß were detected by ELISA at each stimulating time. RESULTS: The Rv3671c protein of M.tuberculosis was successfully expressed in Escherichia coli. The purity of recombinant Rv3671c protein was 95%, and the protein concentration was up to 0.4 mg/ml. The nucleus of THP-1 was isolated and necrosis-like under fluorescence when cells were stimulated by Rv3671c protein. The levels of TNF-α and IL-1ß in supernatant were 19 000 and 16 500 pg/ml respectively, and were significantly higher than control cells with the levels of 2100 and 3800 pg/ml separately. CONCLUSION: The necrosis of THP-1 cells could be stimulated by Rv3671c protein of M.tuberculosis and it was probably associated with high cytokines TNF-α and IL-1ß levels.

CD25 is a novel marker of hepatic bile canaliculus.

OBJECTIVE: Although many antigens have been investigated, the method for the bile canaliculus staining using optical microscopy needs to be improved. The aim of the present study was to assess the expression pattern of a candidate marker, CD25, in normal and diseased liver tissue. METHODS: Immunohistochemistry, immunofluorescence, and immune electron microscopy assays were performed with 41 liver sections and 2 different anti-CD25 monoclonal antibodies. A polyclonal antibody against carcinoembryonic antigen (CEA) was also used to stain bile canaliculus as a control. CD25 expression levels in normal and diseased liver tissue were also determined. RESULTS: CD25 was predominantly localized at the bile canaliculus of adult and infantile liver, evidenced by both immunohistochemistry and immunofluorescence assays. The electron microscopy assay showed that there were obvious amorphous electron-dense deposits at the bile canaliculus. In contrast, the CEA-positive area included bile canaliculus as well as basolateral aspects of hepatocytes. CD25 expression levels did not differ significantly among different disease states. CONCLUSION: This study provides the first evidence that CD25 is a novel marker of bile canaliculus. Characteristics of CD25 expression may shed light on immunohistochemistry and immunofluorescence analysis of bile canaliculus in both basic and clinical hepatic investigations.