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HIV causes rapid CD4+ T cell depletion in the gut mucosa, resulting in immune deficiency and defects in the intestinal epithelial barrier. Breakdown in gut barrier integrity is linked to chronic inflammation and disease progression. However, the early effects of HIV on the gut epithelium, prior to the CD4+ T cell depletion, are not known. Further, the impact of early viral infection on mucosal responses to pathogenic and commensal microbes has not been investigated. We utilized the SIV model of AIDS to assess the earliest host-virus interactions and mechanisms of inflammation and dysfunction in the gut, prior to CD4+ T cell depletion. An intestinal loop model was used to interrogate the effects of SIV infection on gut mucosal immune sensing and response to pathogens and commensal bacteria in vivo. At 2.5 days post-SIV infection, low viral loads were detected in peripheral blood and gut mucosa without CD4+ T cell loss. However, immunohistological analysis revealed the disruption of the gut epithelium manifested by decreased expression and mislocalization of tight junction proteins. Correlating with epithelial disruption was a significant induction of IL-1β expression by Paneth cells, which were in close proximity to SIV-infected cells in the intestinal crypts. The IL-1β response preceded the induction of the antiviral interferon response. Despite the disruption of the gut epithelium, no aberrant responses to pathogenic or commensal bacteria were observed. In fact, inoculation of commensal Lactobacillus plantarum in intestinal loops led to rapid anti-inflammatory response and epithelial tight junction repair in SIV infected macaques. Thus, intestinal Paneth cells are the earliest responders to viral infection and induce gut inflammation through IL-1β signaling. Reversal of the IL-1β induced gut epithelial damage by Lactobacillus plantarum suggests synergistic host-commensal interactions during early viral infection and identify these mechanisms as potential targets for therapeutic intervention.

The Macrobrachium rosenbergii nodavirus (MrNV), the causative agent of white‐tail disease (WTD) in many species of shrimp and prawn, has been shown to infect hemocytes and tissues such as the gills and muscles. However, little is known about the host surface molecules to which MrNV attach to initiate infection. Therefore, the present study investigated the role of glycans as binding molecules for virus attachment in susceptible tissues such as the gills. We established that MrNV in their virus‐like particle (MrNV‐VLP) form exhibited strong binding to gill tissues and lysates, which was highly reduced by the glycan‐reducing periodate and PNGase F. The broad, fucose‐binding Aleuria Aurantia lectin (AAL) highly reduced MrNV‐VLPs binding to gill tissue sections and lysates, and efficiently disrupted the specific interactions between the VLPs and gill glycoproteins. Furthermore, mass spectroscopy revealed the existence of unique fucosylated LacdiNAc‐extended N‐linked and O‐linked glycans in the gill tissues, whereas beta‐elimination experiments showed that MrNV‐VLPs demonstrated a binding preference for N‐glycans. Therefore, the results from this study highly suggested that MrNV‐VLPs preferentially attach to fucosylated N‐glycans in the susceptible gill tissues, and these findings could lead to the development of strategies that target virus‐host surface glycan interactions to reduce MrNV infections. [ABSTRACT FROM AUTHOR]

Selection of embryos with potentially successful development is paramount to ensuring their viability and growth. While morphological assessment has been the mainstay of embryo selection, the identification of proteins that are expressed in the more reproductively successful fast-cleaving embryos as opposed to slow-cleaving ones may serve to reduce visual assessment of subjectivity in bovine. Through the use of proteomic mass spectrometric techniques, we found that 2387 proteins were commonly identified in both fast and slow-cleaving embryos, while 464 proteins were differentially identified. Slowcleaving embryos showed a higher percentage of identified proteins involved in apoptotic processes, DNA repair and stress responses, while fast-cleaving bovine embryos showed a higher percentage of proteins identified that are involved in cell metabolism, gene transcription, and signal transduction. These differential protein expressions identified in the fast- and slowcleaving embryos may serve as alternative potential markers of healthy pre-implantation embryos and improve overall bovine reproductive rate. [ABSTRACT FROM AUTHOR]