Thomas G Pistole's research while affiliated with University of New Hampshire and other places

... Induction of pro-inflammatory responses and stimulation of associated cell-signaling processes have been described for various bacterial porins [4]. In addition, porins have been reported to be involved in the pathogenesis process, like host cell invasion, adherence and induction of apoptosis [5][6][7][8]. Further, porins from various gramnegative pathogenic bacteria have been considered as potential vaccine candidates. For example, porins from Salmonella typhi and Neisserial species have been reported to offer a protective effect against infection [9,10]. ...

... The level of invF was the same as that of the WT strain, whereas the ompF level was significantly elevated ( Figure 2E). The bacterial outer membrane protein ompF is a porin that is recognized by macrophages, leading to phagocytosis [37,38]. This molecule is crucial to bacterial homeostasis, structural integrity, and virulence. ...

... Lactobacillus rhamnosus (LGG) was labelled with FITC as adapted from Smith et al. (1998) and optimized for dye concentration and incubation period. 1 ml of overnight LGG culture was removed from the culture flask, put in an Eppendorf tube and centrifuged for 3 min at 12,000 g. The supernatant was discarded and the pellet was re-suspended in 1 ml of 1 µg/ml FITC working solution and incubated for 60 minutes at 25°C. ...

... Assay of adhesion to J774 macrophages. The adhesion assay was adapted from Athamna and Ofek (3) and Sloan and Pistole (41). For adhesion assays, 48-h cultures of J774 cells were scraped, washed once with PBS, and resuspended at 10 6 cells/ml in DMEM-10% hiFBS (unless specified otherwise). ...

... Because the susceptible population may be compromised in their ability to produce protective levels of either complement or speci¢c antibody, nonopsonic phagocytosis may be a major host defense mechanism in GBS infection. Previous studies in our laboratory have shown that murine macrophages bind GBS in the absence of exogenous opsonins [4]. ...

... The infection begins with the ingestion of contaminated food or water. The pathogen reaches the ileum and invades epithelial host cells that ultimately transported across the intestinal mucosa to mononuclear phagocytes in the underlying lamina propria [3]. The adherence of Salmonella to macrophages has been shown to be mediated by lipopolysaccharide (LPS) and complement receptors [3]. ...

... Though the functional significance of such aggregate formation in vivo (Figure 7) needs additional clarification, the toxicity of OmpC and OmpF amyloids to mammalian cells (Figure 4) suggests that amyloid aggregate formation by OmpC and OmpF could represent a novel mechanism mediating the pathogenesis of Enterobacteriaceae species. The OmpC and OmpF are known to be involved in the processes controlling virulence and antibiotic resistance [59,60]. The ompC and ompF deletions result in the attenuation of the bacterial virulence and colonization capacity [7,61], which might reflect not only the loss of OmpC and OmpF porin activity but also their ability to form amyloids. ...

... We also found induction of IL-6 response after infection. A previous study showed that PMN recruitment due to S. Typhimurium infection induced IL-6 secretion from intestinal epithelial cells [56]. IL-6 also increases the expression of endothelial leukocyte adhesion molecules (VCAM-1, ICAM-1), further promoting leukocyte accumulation [57,58]. ...

... Adhesion to and invasion of host cells are crucial steps in Salmonella infection. Many adhesive structures such as fimbrial and non-fimbrial proteins were found in Salmonella, including type I fimbriae, autotransporter adhesins, and the outer membrane protein OmpD [1,[44][45][46]]. ...

... After harvesting and washing once with PBS and medium, macrophages were suspended (2 × 10 7 ) in 1 ml of solution C plus 4 μM PKH-26 (Sigma-Aldrich) for 5 min as recommended. 33 The reaction was terminated by the addition of an equal volume of serum for 1 min, and then of complete medium. Macrophages were washed three times with fresh medium and were seeded at 5 × 10 5 per well in 24-well plates. ...