The less differentiated the donor cells are used in nuclear transfer (NT), the more easily are they reprogrammed by the recipient cytoplasm. In this context, mesenchymal stem cells (MSCs) appear as an alternative to donor nuclei for NT. The amniotic fluid and adipose tissue are sources of MSCs that have not been tested for the production of cloned embryos in cattle. The objective of this study was to isolate, characterize, and use MSCs derived from amniotic fluid (MSC-AF) and adipose tissue (MSC-AT) to produce cloned calves. Isolation of MSC-AF was performed using in vivo ultrasound-guided transvaginal amniocentesis, and MSC-AT were isolated by explant culture. Cellular phenotypic and genotypic characterization by flow cytometry, immunohistochemistry, and RT-PCR were performed, as well as induction in different cell lineages. The NT was performed using MSC-AF and MSC-AT as nuclear donors. The mesenchymal markers of MSC were expressed in bovine MSC-AF and MSC-AT cultures, as evidenced by flow cytometry, immunohistochemistry, and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes, and adipocytes. Embryo production was similar between the cell types, and two calves were born. The calf from MSC-AT was born healthy, and this fact opens a new possibility of using this type of cell to produce cloned cattle by NT.

The ability of human milk, as well as its protein fractions, to inhibit the adhesion and invasion of Salmonella typhimurium to HeLa cells was investigated. The results revealed that milk secretory immunoglobulin A (sIgA) inhibited neither the adherence nor the bacterial invasion; however, free secretory component and lactoferrin inhibited the bacterial adhesion and interacted with several bacterial proteins. Our data indicated that glycoproteins such as free secretory component and lactoferrin could act as protective compounds against infant enteric diseases, possibly binding to bacterial surface and blocking adhesion, the primordial step of S. typhimurium infection.

Wharton's jelly is a source of mesenchymal stem cells (MSCs) that had not yet been tested for bovine embryo production by nuclear transfer (NT). Thus, the objective of this study was to isolate, characterize and test MSCs derived from Wharton's jelly for embryo and pregnancy RESUMO A geleia de Wharton é uma fonte de células tronco mesenquimais (CTMs) que ainda não havia sido testada para a produção de embriões bovinos por transferência nuclear (TN). O objetivo deste estudo foi isolar, caracterizar e testar as CTMs derivadas da geleia de Wharton para produção de embriões e gestações por transferência nuclear em bovinos. O cordão umbilical foi coletado durante o nascimento e as células derivadas da geleia de Wharton (CGWs) foram isoladas por explante e cultivadas em

Enterotoxigenic Escherichia coli (ETEC) is the most common cause of diarrhea in children in developing countries and among travelers to ETEC endemic areas. ETEC diarrhea is caused by colonization of the small intestine mediated by colonization factor (CF) antigens, and subsequent elaboration of enterotoxins. Breast feeding has been related to protection against enteric infections. The protective effect of human milk can be ascribed to its immunoglobulin content, specially secretory immunoglobulin A (sIgA), and to nonimmunoglobulin components such as free oligosaccharides, glycoproteins and glycolipids. In this study we investigated the effect of whole human milk and its fractions immunoglobulin and non-immunoglobulin on the adherence of ETEC strains possessing different CFs to Caco-2 cells, as well as the ability of sIgA and free secretory component (fSC) to bind to bacterial superficial proteins. Pooled human milk from three donors were fractionated by gel filtration and analyzed by SDS-PAGE. Our results revealed that whole human milk and its proteins fractions, containing sIgA and fSC, inhibited adhesion ETEC strains harboring different colonization factors antigens. We also verified that sIgA and fSC, using immunoblotting and immunogold labeling assays, bound to some fimbrial proteins and other material present in bacterial surface. Our findings suggest that whole human milk and its fractions may contribute to protection against ETEC infections by blocking bacterial adhesion mediated by different colonization antigens.

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