Effects of <i>Lactobacillus paracasei</i> MCC1849 on total IgA production in mice.

<p>(A) Mice were treated with or without MCC1849 for 5 weeks. Total IgA concentrations in homogenized small intestine and serum samples were determined via ELISA. (B) The proportions of IgA⁺ B220⁺ cells and IgA⁺ plasmablasts (IgA⁺ B220^- cells) in PPs were analyzed via FCM. (C) Gene expression related to the differentiation of IgA⁺ cells was measured via real-time RT-PCR analysis. The level of gene expression was normalized to that of GAPDH mRNA expression in the control group. Data are shown as the mean ± SD. N = 16. *p<0.05, **p<0.01 compared to the control.</p

Orally administered heat-killed <i>Lactobacillus paracasei</i> MCC1849 enhances antigen-specific IgA secretion and induces follicular helper T cells in mice

<div><p>Antigen-specific immunoglobulin (Ig) A plays a major role in host defense against infections in gut mucosal tissue. Follicular helper T (Tfh) cells are located in germinal centers and promote IgA production via interactions with germinal center B cells. Several studies have demonstrated that some lactic acid bacteria (LAB) strains activate the host’s acquired immune system, inducing IgA secretion in the intestine. However, the precise molecular mechanisms underlying the effects of LAB on IgA production and Tfh cells are not fully resolved. <i>Lactobacillus paracasei</i> MCC1849 is a probiotic strain isolated from the intestine of a healthy adult. In this study, we investigated the effects of orally administered heat-killed MCC1849 on IgA production in the intestine and on Tfh cell induction <i>in vivo</i>. We found that orally administered MCC1849 induced antigen-specific IgA production in the small intestine, serum and lungs. We also observed that MCC1849 increased the proportion of IgA⁺ B cells and Tfh cells in Peyer’s patches (PPs). In addition, MCC1849 increased the gene expression of IL-12p40, IL-10, IL-21, STAT4 and Bcl-6 associated with Tfh cell differentiation. These results suggest that orally administered MCC1849 enhances antigen-specific IgA production and likely affects Tfh cell differentiation in PPs.</p></div

Effects of <i>Lactobacillus paracasei</i> MCC1849 on IL-12 production.

<p>Murine splenocytes were cultured with various heat-killed <i>Lactobacillus</i> strains (10 μg/ml) for 2 days. Data shown are the mean ± SD of the levels of IL-12p70 which are the representative of three independent experiments.</p

Effects of <i>Lactobacillus paracasei</i> MCC1849 on total IgA and OVA-specific IgA production in OVA-immunized mice.

<p>(A, B) Mice were treated with or without MCC1849 for 5 weeks. All mice were orally immunized on days 14, 21, and 28 with OVA and cholera toxin. On day 35, mice were euthanized and dissected. Data show the total IgA and OVA-specific IgA concentrations in homogenized small intestine, small-intestine lavage fluid, homogenized colon, colon contents, serum and lung samples. AU: arbitrary unit. Data are shown as the mean ± SD. N = 14. Data are representative three independent experiments. *p<0.05, **p<0.01 compared to the control.</p

Effects of <i>Lactobacillus paracasei</i> MCC1849 on the population of T cells and gene expression in PP cells in OVA-immunized mice.

<p>(A) The proportion of Tfh cells (CD4⁺ CXCR5⁺ PD-1^high cells) and Th1 cells (CD4⁺ T-bet⁺ cells) in PPs were analyzed via FCM. (B) Gene expression related to T cell differentiation was measured via real-time RT-PCR analysis. The level of gene expression was normalized to that of GAPDH mRNA expression in the control group. Data are shown as the mean ± SD. n = 14. Data are representative two independent experiments. *p<0.05, **p<0.01 compared to the control.</p

Effects of <i>Lactobacillus paracasei</i> MCC1849 on the population of IgA-related cells in the intestinal tissues of OVA-immunized mice.

<p>(A, B and C) The proportion of IgA⁺ B220⁺ cells and IgA⁺ plasmablasts (IgA⁺ B220^- cells) in PP, MLN and LP cell samples were analyzed via FCM. Data are shown as the mean ± SD. N = 14. Data are representative two independent experiments. *p<0.05, **p<0.01 compared to the control.</p

Additional file 10: of Age-related changes in gut microbiota composition from newborn to centenarian: a cross-sectional study

Taxa that are found in more than 50 % of the subjects in any cluster (shown in Additional file 8) with significantly difference between adult 1 and adult 2 clusters. (XLSX 857 kb

Additional file 13: of Age-related changes in gut microbiota composition from newborn to centenarian: a cross-sectional study

Hierarchical Ward’s linkage clustering based on the proportion of transporter genes predicted by PICRUSt. Age-related groups (adult-enriched and infant/elderly-enriched clusters) were revealed by Ward’s linkage clustering using the squared Euclidean distance. The population densities (z-score) of the transporters scaled by color are displayed together with a dendrogram of the transporters in a heat map. The colors within the horizontal clustering represent the age-segmented groups as shown in Fig. 1 The color code for the vertical clustering indicates KEGG Orthology (KO) as follows: white, ABC Transporters, Eukaryotic Type; yellow, ABC Transporters, Prokaryotic Type; blue, Solute Carrier Family (SLC); orange, Major Facilitator Superfamily (MFS); red, Phosphotransferase System (PTS); and green, Other Transporters. (PDF 209 kb

Additional file 14: of Age-related changes in gut microbiota composition from newborn to centenarian: a cross-sectional study

Relative abundance of predicted D-Xylose transporter (KEGG module: M00215). The KEGG module M00215 consists of three KO entries, K10543, K10544 and K10545. Each number indicates a group as shown in Table 1. Box-plots show the interquartile range (IQR) of the relative abundance of the predicted D-Xylose transporter. Open circles indicate outliers from 1.5- to 3.0-fold IQR. (PDF 96 kb

Selection of bacterial strains with immunomodulatory capacities.

<p>Bacteria were evaluated by studying (A) the mitogenic assay and expression of cytokines in porcine Peyer_$B!G_(Bs patches (B), mesenteric lymphoid nodes (C), and porcine intestinal epithelial cells (D). Cells were pre-treated with different bacterial strains for 48 h, and then the mitogenic activity or the expression of MCP-1, IL-6, and IL-8 were measured. The results represent four independent experiments. Different letters indicate significant differences (P<0.05).</p