Induction by Herpes Simplex Virus of Free and Heteromeric Forms of E2F Transcription Factor

We have determined that HSV causes rapid and large increases in cell-cycle-regulated free E2F and S-phase p107/E2F DNA binding activities in asynchronous cultures of C33A cells. Induction occurred by 4 hr postinfection and coincided with the appearance of viral encoded immediate-early and delayed-early proteins, i.e., when viral DNA replication normally commences. No increase in E2F activities occurred when cells were infected with viruses expressing mutant regulatory proteins ICP4 or ICP27, or mutant replication proteins ICP8, pol or helicase, or when cells were infected with wild-type virus in the presence of inhibitors of DNA synthesis. In contrast, ICP8 mutant-infected cells contained elevated amounts of NF kappa B activity equivalent to WT virus, no induction of Sp1 relative to WT virus, and reduced ATF/CREB activity relative to WT virus. Results of transient expression assays with E2F-responsive reporters indicated that the net effect of induction of both active (free E2F) and repressive (p107/E2F) complexes was a decrease in AdE2 promoter activity and an increase in c-myc promoter activity. Taken together these results suggest that HSV can cause unscheduled changes in the amount and functional status of a cell-cycle-regulated transcription factor. These results are discussed in light of possible roles for viral-induced alterations in E2F, especially as related to imposing or overriding cell-cycle checkpoints

Impact of 2′-fucosyllactose on gut microbiota composition in adults with chronic gastrointestinal conditions: batch culture fermentation model and pilot clinical trial findings

Intestinal dysbiosis has been described in patients with certain gastrointestinal conditions including irritable bowel syndrome (IBS) and ulcerative colitis. 2′-fucosyllactose (2′-FL), a prebiotic human milk oligosaccharide, is considered bifidogenic and butyrogenic. To assess prebiotic effects of 2′-FL, alone or in combination with probiotic strains (potential synbiotics), in vitro experiments were conducted on stool from healthy, IBS, and ulcerative colitis adult donors. In anaerobic batch culture fermenters, Bifidobacterium and Eubacterium rectale-Clostridium coccoides counts, and short-chain fatty acids (SCFAs) including butyrate increased during fermentation with 2′-FL and some of the 2′-FL/probiotic combinations. In a subsequent open-label pilot trial, the effect of a 2′-FL-containing nutritional formula was evaluated in twelve adults with IBS or ulcerative colitis. Gastrointestinal Quality of Life Index (GIQLI) total and gastrointestinal symptoms domain scores, stool counts of Bifidobacterium and Faecalibacterium prausnitzii, and stool SCFAs including butyrate, increased after six weeks of intervention. Consistent with documented effects of 2′-FL, the batch culture fermentation experiments demonstrated bifidogenic and butyrogenic effects of 2′-FL during fermentation with human stool samples. Consumption of the 2′-FL-containing nutritional formula by adults with IBS or ulcerative colitis was associated with improvements in intra- and extra-intestinal symptoms, and bifidogenic and butyrogenic effects

Serotype-specific differences in inhibition of reovirus infectivity by human-milk glycans are determined by viral attachment protein σ1

AbstractHuman milk contains many bioactive components, including secretory IgA, oligosaccharides, and milk-associated proteins. We assessed the antiviral effects of several components of milk against mammalian reoviruses. We found that glucocerebroside (GCB) inhibited the infectivity of reovirus strain type 1 Lang (T1L), whereas gangliosides GD3 and GM3 and 3′-sialyllactose (3SL) inhibited the infectivity of reovirus strain type 3 Dearing (T3D). Agglutination of erythrocytes mediated by T1L and T3D was inhibited by GD3, GM3, and bovine lactoferrin. Additionally, α-sialic acid, 3SL, 6′-sialyllactose, sialic acid, human lactoferrin, osteopontin, and α-lactalbumin inhibited hemagglutination mediated by T3D. Using single-gene reassortant viruses, we found that serotype-specific differences segregate with the gene encoding the viral attachment protein. Furthermore, GD3, GM3, and 3SL inhibit T3D infectivity by blocking binding to host cells, whereas GCB inhibits T1L infectivity post-attachment. These results enhance an understanding of reovirus cell attachment and define a mechanism for the antimicrobial activity of human milk

Microbes central to human reproduction

As studies uncover the breadth of microbes associated with human life, opportunities will emerge to manipulate and augment their functions in ways that improve health and longevity. From involvement in the complexities of reproduction and fetal/infant development, to delaying the onset of disease, and indeed countering many maladies, microbes offer hope for human well-being. Evidence is emerging to suggest that microbes may play a beneficial role in body sites traditionally viewed as being sterile. Although further evidence is required, we propose that much of medical dogma is about to change significantly through recognition and understanding of these hitherto unrecognized microbe–host interactions. A meeting of the International Scientific Association for Probiotics and Prebiotics held in Aberdeen, Scotland (June 2014), presented new views and challenged established concepts on the role of microbes in reproduction and health of the mother and infant. This article summarizes some of the main aspects of these discussions

Lactation and neonatal nutrition: defining and refining the critical questions.

This paper resulted from a conference entitled "Lactation and Milk: Defining and refining the critical questions" held at the University of Colorado School of Medicine from January 18-20, 2012. The mission of the conference was to identify unresolved questions and set future goals for research into human milk composition, mammary development and lactation. We first outline the unanswered questions regarding the composition of human milk (Section I) and the mechanisms by which milk components affect neonatal development, growth and health and recommend models for future research. Emerging questions about how milk components affect cognitive development and behavioral phenotype of the offspring are presented in Section II. In Section III we outline the important unanswered questions about regulation of mammary gland development, the heritability of defects, the effects of maternal nutrition, disease, metabolic status, and therapeutic drugs upon the subsequent lactation. Questions surrounding breastfeeding practice are also highlighted. In Section IV we describe the specific nutritional challenges faced by three different populations, namely preterm infants, infants born to obese mothers who may or may not have gestational diabetes, and infants born to undernourished mothers. The recognition that multidisciplinary training is critical to advancing the field led us to formulate specific training recommendations in Section V. Our recommendations for research emphasis are summarized in Section VI. In sum, we present a roadmap for multidisciplinary research into all aspects of human lactation, milk and its role in infant nutrition for the next decade and beyond

In vivo and in vitro models of intestinal intraepithelial lymphocyte development

Intestinal intraepithelial lymphocytes (IELs) make up a vast, but poorly understood population of lymphocytes. Located between epithelial cells that line the gut, they may provide a first line of defense against invading pathogens. Intriguingly, the largest population of IELs, TCRγδ+CD8αα + T cells, appears to be extrathymically derived. A more complete understanding of the origin of these cells may lead to a better understanding of their function. We, therefore, have utilized both in vivo and in vitro experimental systems to investigate IEL development. In vivo, the absence of IL-2, in IL-2 deficient (IL-2−/− ) mice, leads to reduced TCRγδ+CD8αα + IELs. Additionally, this reduction in TCRγδ+ IELs is not secondary to the colitis seen in IL-2−/− mice, as it is also present in gnotobiotic IL-2−/− mice. Furthermore, hematopoietic progenitor cells from IL-2 −/− bone marrow have an intrinsic defect in their ability to regenerate TCRγδ+ IELs after transfer to irradiated, CD45 congenic recipients. IL-2, therefore, appears to play an important role in IEL development. Given the limitations of using in vivo systems to dissect IEL development, in addition to the possibility that intestinal epithelial cells may play a key role in promoting IEL development, we have developed an in vitro model. A culture system has been developed in which freshly isolated small intestinal epithelial cells are cultured with hematopoietic progenitor enriched bone marrow cells. Preliminary experiments reveal that after 30 days of co-culture clusters of cells can be seen in close contact with the epithelial cell layer. These clusters appear to be negative for the expression of such lymphoid specific genes as RAG, Ets-1, AIOLOS and GATA-3. After relocation of the laboratory to the United Kingdom, primary IEC cultures were not re-established. Further experimentation needs to be conducted in order to confirm that IEC can support IEL development. The in vitro model system will provide a useful tool for further study of IEL development

In vivo and in vitro models of intestinal intraepithelial lymphocyte development

Intestinal intraepithelial lymphocytes (IELs) make up a vast, but poorly understood population of lymphocytes. Located between epithelial cells that line the gut, they may provide a first line of defense against invading pathogens. Intriguingly, the largest population of IELs, TCRγδ+CD8αα + T cells, appears to be extrathymically derived. A more complete understanding of the origin of these cells may lead to a better understanding of their function. We, therefore, have utilized both in vivo and in vitro experimental systems to investigate IEL development. In vivo, the absence of IL-2, in IL-2 deficient (IL-2−/− ) mice, leads to reduced TCRγδ+CD8αα + IELs. Additionally, this reduction in TCRγδ+ IELs is not secondary to the colitis seen in IL-2−/− mice, as it is also present in gnotobiotic IL-2−/− mice. Furthermore, hematopoietic progenitor cells from IL-2 −/− bone marrow have an intrinsic defect in their ability to regenerate TCRγδ+ IELs after transfer to irradiated, CD45 congenic recipients. IL-2, therefore, appears to play an important role in IEL development. Given the limitations of using in vivo systems to dissect IEL development, in addition to the possibility that intestinal epithelial cells may play a key role in promoting IEL development, we have developed an in vitro model. A culture system has been developed in which freshly isolated small intestinal epithelial cells are cultured with hematopoietic progenitor enriched bone marrow cells. Preliminary experiments reveal that after 30 days of co-culture clusters of cells can be seen in close contact with the epithelial cell layer. These clusters appear to be negative for the expression of such lymphoid specific genes as RAG, Ets-1, AIOLOS and GATA-3. After relocation of the laboratory to the United Kingdom, primary IEC cultures were not re-established. Further experimentation needs to be conducted in order to confirm that IEC can support IEL development. The in vitro model system will provide a useful tool for further study of IEL development