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Mitochondrial biogenesis is inherent to adipocyte differentiation. Mitochondrial dysfunction leads to abnormal lipid accumulation or the deterioration of the differentiation process. The aim of this study is to investigate the mitochondrial development during the differentiation of rat primary adipocytes and the effect of mitochondrial dysfunction on this process. We found, for the first time, that the number of mitochondria markedly increased during adipocyte differentiation by transmission electron microscopy. By immunofluorescence staining that the protein content of Cyt c increased in differentiated adipocyte in comparison with preadipocyte. The mRNA expression levels of mitochondrial gene including cytochromes c (Cyt c), malate dehydrogenases (MDH), and peroxisome proliferator activated receptor (PPAR) gamma coactivator-1beta (PGC-1beta) significantly increased along with the proceeding of adipocyte differentiation. The damage to mitochondrial respiratory chain function by rotenone caused significant decrease in gene expressions including mitochondrial MDH and PGC-1beta, and PPARgamma, CAAT/enhancer binding protein alpha (C/EBPalpha) and sterol regulatory element binding protein-1c (SREBP-1c), which are known as transcription factors of differentiation, and differentiation marker gene named fatty acid synthetase. Moreover, an apparent decrease was found in the synthesis of triglyceride and ATP due to the damage to mitochondria by rotenone. Based on the above results, our present study revealed that the density and oxidative capacity of mitochondrial markedly increased during primary adipocyte differentiation, and on the other hand, we suggested that mitochondria dysfunction might inhibit the differentiation process.

Neutrophil extracellular traps (NETs), composed primarily of DNA and proteases, are released from activated neutrophils and contribute to the innate immune response by capturing pathogens. Plasmodium falciparum, the causative agent of severe malaria, thrives in its host by counteracting immune elimination. Here, we report the discovery of a novel virulence factor of P. falciparum, a TatD-like DNase (PfTatD) that is expressed primarily in the asexual blood stage and is likely utilized by the parasite to counteract NETs. PfTatD exhibits typical deoxyribonuclease activity, and its expression is higher in virulent parasites than in avirulent parasites. A P. berghei TatD-knockout parasite displays reduced pathogenicity in mice. Mice immunized with recombinant TatD exhibit increased immunity against lethal challenge. Our results suggest that the TatD-like DNase is an essential factor for the survival of malarial parasites in the host and is a potential malaria vaccine candidate.

mediated signaling may play a suppressive role in immune response. We previously found that the cAMPelevators (CTx and 8-Br-cAMP) inhibited IL-12, IL-1a, IL-6 gene expression, but increased the transcriptional levels of IL-10 and IL-1Ra in LPS-treated murine peritoneal macrophages. The present study examined a possible molecular mechanism involved in cAMP elevators-induced inhibition of IL-12 p40 expression in response to LPS. Our data demonstrated that cAMP elevators downregulated IL-12 p40 mRNA expression and IL-12 p70 production in murine peritoneal macrophages. Subsequent studies revealed that cAMP-elevators blocked phosphorylation of p38 MAPK, but did not affect the activity of NF-B binding to . This is the first report that cAMP elevators inhibit LPS-induced IL-12 production by a mechanism that is associated, at least in part, with p38-dependent inhibition by cAMP signaling pathways.

The digestive systems of mammals harbor a complex gut microbiome, comprising bacteria and other microorganisms that confer metabolic and immunological benefits to the host. Ruminants that digest plant-based foods have a four-compartment stomach consisting of the rumen, reticulum, omasum, and abomasum. The microorganisms in the stomach are essential for providing the host with critical nutrients. However, the majority of these microorganisms are unknown species. The microbiome of the stomach is diverse, and the majority of these organisms cannot be cultured. Next-generation sequencing (NGS) combined with bioinformatic analysis tools have allowed the dissection of the composition of the microbiome in samples collected from a specific environment. In this study, for the first time, the bacterial composition in two compartments, the reticulum and the omasum, of bovine were analyzed using a metagenomic approach and compared to the bacterial composition of the rumen. These data will assist in understanding the biology of ruminants and benefit the agricultural industry. The diversity and composition of the bacterial community in samples collected from the rumen, reticulum, and omasum of bovines in the Changchun Region of Northeast China were analyzed by sequencing the V3 region of the 16S rRNA gene using a barcoded Illumina paired-end sequencing technique, and the primary composition of the microbiome in the rumen, reticulum, and omasum of the bovines was determined. These microbiomes contained 17 phyla and 107 genera in all three samples. Five phyla, Bacteroidetes, Firmicutes, Proteobacteria, Spirochaetes, and Lentisphaerae, were the most abundant taxonomic groups. Additionally, the different stomach compartments harbored different compositions of the microorganisms.Electronic supplementary materialThe online version of this article (doi:10.1007/s13353-014-0258-1) contains supplementary material, which is available to authorized users.

A B S T R A C T Effects of human fibroblast (,) or leukocyte (a) interferon (IFN) on differentiations of a human histiocytic lymphoma-derived cell line (U937) or promyelocytic leukemia-derived cell line (HL-60) were studied. When cultured with ,B-IFN (400-1,000 U/ml), U937 cells showed gross morphologic and microscopic changes consisting of clumping, increased cytoplasmic-to-nuclear ratio, enhanced prominence of cytoplasmic granules, and membrane ruffling. After culture with #l-IFN, the number of U937 cells reactive with B43.4.1 monoclonal antibody, which is specific for human monocytes, natural killer cells, and neutrophils, increased from <10% of U937 cells to 47%. ,B-IFN treatment also enhanced antibody-dependent cellular cytotoxicity against chicken erythrocytes by U937 cells. The same morphologic, phenotypic, and functional changes were also observed when U937 were treated with recombinant or natural a-IFN. The effects of a-IFN were totally abolished by anti-a-IFN serum. In contrast, HL-60, which differentiates toward cells of the monocyte lineage in response to phorbol 12-myristate 13-acetate (based on the above criteria), and toward granulocytes in response to dimethyl sulfoxide, did not differentiate when cultured with a-or ,B-IFN. No consistent relationship between induction of differentiation and changes in phospholipid methylation were observed.

Glucuronoxylomannan (GXM), the major component of the capsular polysaccharide of Cryptococcus neoformans, is essential to virulence of the yeast. Previous studies found that the interaction between GXM and phagocytic cells has biological consequences that may contribute to the pathogenesis of cryptococcosis. We found that GXM binds to and is taken up by murine peritoneal macrophages. Uptake is dose and time dependent. Examination of the sites of GXM accumulation by immunofluorescence microscopy showed that the pattern was discontinuous and punctate both on the surfaces of macrophages and at intracellular depots. Although resident macrophages showed appreciable accumulation of GXM, uptake was greatest with thioglycolate-elicited macrophages. A modest stimulation of GXM binding followed treatment of resident macrophages with phorbol 12-myristate 13-acetate, but treatment with lipopolysaccharide or gamma interferon alone or in combination had no effect. Accumulation of GXM was critically dependent on cytoskeleton function; a near complete blockade of accumulation followed treatment with inhibitors of actin. GXM accumulation by elicited macrophages was blocked by treatment with inhibitors of tyrosine kinase, protein kinase C, and phospholipase C, but not by inhibitors of phosphatidylinositol 3-kinase, suggesting a critical role for one or more signaling pathways in the macrophage response to GXM. Taken together, the results demonstrate that it is possible to experimentally enhance or suppress binding of GXM to macrophages, raising the possibility for regulation of the interaction between this essential virulence factor and binding sites on cells that are central to host resistance.Cryptococcus neoformans is the etiological agent of cryptococcosis, an opportunistic infection that may produce a lifethreatening meningoencephalitis in immunocompromised patients. The yeast is surrounded by a polysaccharide capsule that is essential to virulence (3, 11). The primary constituent of the capsule is glucuronoxylomannan (GXM), a high-molecularweight polysaccharide that can be isolated from supernatant fluids of yeast cultures and may be found in high concentrations in serum and cerebrospinal fluid samples from patients with cryptococcosis. GXM has an ␣-1,3-linked mannose backbone that is O acetylated and substituted with single side chains of xylose and glucuronic acid (2, 5).There are several direct and indirect lines of evidence for binding and/or uptake of GXM by phagocytic cells. First, large amounts of GXM are shed in vivo, and immunohistochemistry studies have found that GXM accumulates and is stored in tissue macrophages (12,14,16,22). Second, soluble GXM blocks binding of CD18 antibodies to human neutrophils, suggesting an interaction between GXM and neutrophil CD18 (9). Binding and/or ingestion of GXM by macrophages has biological consequences that may contribute to the pathogenesis of cryptococcosis. Potential biological consequences of GXMphagocyte interaction include inhibition of neutrophil influx into sites of in...

BackgroundToxoplasmosis is one of the most common parasitic zoonoses. The seroprevalence of Toxoplasma gondii infection in humans varies widely worldwide. Detection of Toxoplasma-specific antibodies has been a gold standard method for both epidemiological investigation and clinical diagnosis. Genetic investigation indicated that there is a wide distribution of different genome types or variants of the parasite prevalent in different areas. Thus the reliability of using antigens from parasites of a single genome type for diagnosis and epidemiology purposes needs to be extensively evaluated.MethodsIn this study, the prevalence of T. gondii infection among 880 clinically healthy individuals in China was systematically tested using crude soluble native antigens and purified recombinant antigens of type I and II T. gondii. The T. gondii-specific IgG and IgM in the sera was further confirmed using commercial Toxoplasmosis Diagnosis Kits and Western blot assays.ResultsThe sero-prevalence of T. gondii-specific IgG detected with crude native Type I and type II antigens was 12.2% and 11.3% respectively. Whereas the overall prevalence was more than 20% when combined with the results obtained with recombinant tachyzoite and bradyzoite antigens. There was an obvious variation in immune-recognition of parasite antigens among the individuals studied.ConclusionsThe general prevalence of anti-T. gondii IgG in the study population was likely much higher than previously reported. The data also suggested that there is more genetic diversity among the T. gondii isolates in China. Further, combination of recombinant antigens with clear immuno-recognition will be able to generate more sensitive diagnostic results than those obtained with crude antigens of T. gondii tachyzoites.