Goat anti Mouse TNF polyclonal antibody [Biotin]

The aim of the study was to investigate the effects of lactic acid on the phenotypic polarization and immune function of macrophages. The human monocyte/macrophage cell line, THP-1, was selected and treated with lactic acid. Immunofluorescence staining, laser confocal microscopy, reverse-transcription polymerase chain reaction (RT-PCR), western blot, siRNA, and ELISA analyses were used to observe changes in the levels of cluster of differentiation (CD)68, CD163, hypoxia inducible factor (HIF)-1 alpha, and programmed death ligand-1 (PD-L1) as well as those of cytokines, tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-12, and IL-10. THP-1 macrophages and T cells were co-culturedin vitroto observe the changes in proliferation and apoptosis of T cells. The results showed that, lactic acid (15 mmol/l) significantly upregulated the expression of the macrophage M(2)marker CD163 (P<0.05), cytokines, IFN-gamma and IL-10, secreted by M-2-tumor-associated macrophages (TAM, P<0.05), and HIF-1 alpha and PD-L1 (P<0.05), and downregulated the expression of cytokines, TNF-alpha and IL-12, secreted by M-1-TAM (P<0.05). Redistribution of M-2-TAM subsets and PD-L1 expression was reversed after further transfection of THP-1 cells with HIF-1 alpha siRNA (P<0.05). After co-culturing, T-cell proliferation was inhibited and apoptosis was promoted. In summary, modulation of lactic acid level can redistribute M-2-TAM subsets and upregulate PD-L1 to assist tumor immune escape. The HIF-1 alpha signaling pathway may participate in this process, revealing that macrophages, as 'checkpoints' in organisms, are links that connect the immune status and tumor evolution, and can be used as a target in tumor treatment.

Background The contents of lipopolysaccharide (LPS) and Toll-like receptor 4 (TLR4) are significantly increased during the progression of nonalcoholic fatty liver disease (NAFLD). The study investigated the role of the LPS/TLR4 signaling pathway in improving gypenosides (Gyp) on NAFLD. Methods NAFLD model were established in rats and treated by Gyp. Pathological changes of liver tissues were observed by Hematoxylin and Eosin (HE) staining. Lipid metabolism and insulin resistance were measured. Expressions of inflammatory factors and protein of LPS/TLR4 downstream pathway were detected by qRT-PCR and Western blotting. THLE-2 cells were treated by free-fatty acid (FFA), Gyp, and LPS, and then transfected with TLR4. Next, cell viability was detected by MTT. Lipid droplet deposition and Triglyceride (TG) content were determined by Oil Red O staining and ELISA. Results Gyp protected fatty liver tissues in NAFLD model, and significantly reversed cholesterol increased by high-fat diet. Moreover, Gyp increased SOD content and decreased the contents of AST, ALT, MDA, HSI, FBG, FINS, HOMA-IR, IL-1 beta, and TNF-alpha, and promoted the expressions of TLR4, LPS, MyD88, p-I kappa B alpha, and reduced the expressions of p-p65 and I kappa B alpha in the NAFLD model. Gyp treatment significantly reduced lipid droplet deposition, increased TG content and MyD88, p-I kappa B alpha, p-p65 in FFA-induced liver cells, but LPS and TLR4 greatly reversed improvement of FFA by Gyp. Conclusion Gypenosides could improve liver function, lipid metabolism, insulin resistance, and levels of inflammatory factors in NAFLD model by regulating LPS/TLR4 signaling pathway in vitro and in vivo.