Mannan-Binding Lectin Suppresses Peptidoglycan-Induced TLR2 Activation and Inflammatory Responses

Figure 1

MBL suppresses PGN-induced inflammatory cytokine production. (a) The mRNA levels of TNF-α and IL-6. PMA-activated THP-1 cells were stimulated with PGN (200 μg/ml), MBL (10 μg/ml) mixed with PGN, or anti-MBL pAb (10 μg/ml) mixed with MBL and PGN; then the cells were incubated at 37°C in a 5% (v/v) CO₂ environment for 24 h. All of the mixture was generated by preincubation for 2 h at room temperature. Total RNA was extracted from the treated cells, and the relative mRNA level of TNF-α and IL-6 was analyzed by qRT-PCR by normalizing to internal β-actin. Value is mean ± SEM of three experiments. . (b) The protein levels of TNF-α and IL-6. PMA-activated THP-1 cells were stimulated as described in (a). The protein levels of TNF-α and IL-6 in the medium were detected by ELISA assays, respectively. Data shown represent three independent experiments with similar results. . (c) Different concentrations of MBL on PGN-induced cytokine production. PMA-activated THP-1 cells were stimulated with PGN (200 μg/ml) or PGN mixed with 0, 5, 10, and 20 (μg/ml) MBL by preincubation for 2 h in room temperature separately. Total cell medium was collected. The protein levels of TNF-α and IL-6 in the medium were detected by ELISA assays. Data shown represent three independent experiments. .

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