Diet-induced obesity reduces the production of influenza vaccine-induced antibodies via impaired macrophage function.

Obesity is a metabolic disease characterized by low-level chronic inflammation. Obese individuals are susceptible to infection by viruses, and vaccination against these pathogens is less effective than in nonobese individuals. Here, we sought to explore the immunological environment in a mouse model of obesity induced by a high-fat diet (HFD). HFD treatment increased the body weight and epididymal fat mass. The proportion of activated B cells, T cells, and macrophages was similar between mice in the HFD group and the regular-fat diet (RFD) group. The Th1 cell subpopulation in the HFD group was increased, whereas the proportion of Treg cells was reduced compared with the RFD group. Moreover, T-cell proliferation and cytokine production did not differ between the groups when cells were stimulated with anti-CD3 and anti-CD28 antibodies in vitro. In macrophages, phagocytic activity was higher in mice fed an HFD than in those fed an RFD, but expression levels of CD86 and MHC class II antigens were similar. When macrophages were cultured in vitro, the proportion of CD86-expressing macrophages was lower in those isolated from mice in the HFD group than in those isolated from the RFD group. Furthermore, lipopolysaccharide-induced interleukin 6 (IL-6) and tumor necrosis factor alpha secretions were significantly reduced in macrophages isolated from the HFD group. In addition, influenza vaccine-induced antibodies in the HFD group diminished more rapidly than in the RFD group. These results suggest that poor functionality of macrophages during obesity might contribute to a reduction in vaccine efficacy.

Biological responses in osteoblast-like cell line according to thin layer hydroxyapatite coatings on anodized titanium.

Several features of the implant surface, such as roughness, topography and composition play a relevant role in implant integration with bone. This study was conducted in order to determine the effects of various thin layer hydroxyapatite (HA) coatings on anodized Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on 100 nm HA (100 nm HA coating on anodized surface), 500-700 nm HA (500-700 nm HA coating on anodized surface), 1 mum HA (1 mum HA coating on anodized surface) and anodize (non-HA coating on anodized surface) Ti. The morphology of these cells was assessed by scanning electron microscopy (SEM). The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the four dental substrate types. MG63 cells cultured on 100 nm HA, 1 mum HA and anodize exhibited cell-matrix interactions. It was 500-700 nm HA surface showing cell-cell interaction. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein 2, latent transforming growth factor beta binding protein 1, catenin (cadherin-associated protein), integrin, PDGFRB and GDF-1 growth differentiation factor 1 were up-regulated on the different surfaces. Several genes, including fibroblast growth factor receptor 3, fibroblast growth factor 12 and CD4 were down-regulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface morphology of the dental materials used.

Effect of various implant coatings on biological responses in MG63 using cDNA microarray.

During the process of bone formation, titanium (Ti) surface is an important factor in the modulation of osteoblastic function. This study was conducted in order to determine the effects of different Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on smooth (S), sandblasted large-grit and acid etching (SLA), hydroxyapatite (HA), hydroxyfluoride (HF), titanium nitrate (TIN), and diamond-like carbon (DLC) Ti. The morphology of these cells were assessed by SEM. The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the six dental substrate types. The SLA and HA surfaces were determined to be rougher than the others. MG63 cells cultured on SLA and HA exhibited cell-matrix interactions. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein, cadherin, integrin, and insulin-like growth factors, were upregulated on the different surfaces. Several genes, including fibroblast growth factor receptor 4, Bcl 2-related protein, and collagen, were downregulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface roughness of the dental materials used.