scholarly journals Filament Tip-Associated Antigens Involved in Adherence to and Invasion of Murine Pulmonary Epithelial Cells In Vivo and HeLa Cells In Vitro by Nocardia asteroides

1998 ◽  
Vol 66 (10) ◽  
pp. 4676-4689 ◽  
Author(s):  
Blaine L. Beaman ◽  
LoVelle Beaman
Keyword(s):  
Epithelial Cells ◽  
Hela Cells ◽  
Nocardia Asteroides ◽  
Pulmonary Epithelial Cells ◽  
Pulmonary Epithelial Cell ◽  
Vitro Model ◽  
The Brain ◽  
Invasion Assays

ABSTRACT The interactions of Nocardia asteroides GUH-2 with pulmonary epithelial cells of C57BL/6 mice and with HeLa cells were studied. Electron microscopy demonstrated that only the tips of log-phase cells penetrated pulmonary epithelial cells following intranasal administration, and nocardiae were recovered from the brain. Coccobacillary cells neither invaded nor disseminated. Serum from immunized mice (IMS) decreased attachment to and penetration of pulmonary epithelial cell surfaces by log-phase GUH-2 and inhibited spread to the brain. IMS was adsorbed against stationary-phase cells. Western immunoblots suggested that this adsorbed IMS was reactive primarily with 43- and 62-kDa proteins. Immunofluorescence showed that adsorbed IMS preferentially labeled the tips of log-phase GUH-2 cells. Since this IMS was reactive to culture filtrate antigens, several of these proteins were cut from gels, and mice were immunized. Sera against 62-, 55-, 43-, 36-, 31-, and 25-kDa antigens were obtained. The antisera against the 43- and 36-kDa proteins labeled the filament tips of GUH-2 cells. Only the antiserum against the 43-kDa antigen increased pulmonary clearance, inhibited apical attachment to and penetration of pulmonary epithelial cells, and prevented spread to the brain. An in vitro model with HeLa cells demonstrated that the tips of log-phase cells of GUH-2 adhered to and penetrated the surface of HeLa cells. Invasion assays with amikacin treatment demonstrated that nocardiae were internalized. Adsorbed IMS blocked attachment to and invasion of these cells. These data suggested that a filament tip-associated 43-kDa protein was involved in attachment to and invasion of pulmonary epithelial cells and HeLa cells by N. asteroides GUH-2.

scholarly journals A Role for Caspases in Lens Fiber Differentiation

1998 ◽  
Vol 140 (1) ◽  
pp. 153-158 ◽  
Author(s):  
Yasuki Ishizaki ◽  
Michael D. Jacobson ◽  
Martin C. Raff
Keyword(s):  
Epithelial Cells ◽  
Cysteine Proteases ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Caspase Family ◽  
Vitro Model ◽  
Normal Differentiation ◽  
Enzymatic Machinery

There is increasing evidence that programmed cell death (PCD) depends on a novel family of intracellular cysteine proteases, called caspases, that includes the Ced-3 protease in the nematode Caenorhabditis elegans and the interleukin-1β–converting enzyme (ICE)-like proteases in mammals. Some developing cells, including lens epithelial cells, erythroblasts, and keratinocytes, lose their nucleus and other organelles when they terminally differentiate, but it is not known whether the enzymatic machinery of PCD is involved in any of these normal differentiation events. We show here that at least one CPP32 (caspase-3)-like member of the caspase family becomes activated when rodent lens epithelial cells terminally differentiate into anucleate lens fibers in vivo, and that a peptide inhibitor of these proteases blocks the denucleation process in an in vitro model of lens fiber differentiation. These findings suggest that at least part of the machinery of PCD is involved in lens fiber differentiation.

scholarly journals First characterization of the probiotic potential of lactic acid bacteria isolated from Costa Rican pineapple silages

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12437
Author(s):  
Jannette Wen Fang Wu Wu ◽  
Mauricio Redondo-Solano ◽  
Lidieth Uribe ◽  
Rodolfo WingChing-Jones ◽  
Jessie Usaga ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Epithelial Cells ◽  
Lactic Acid Bacteria ◽  
Hela Cells ◽  
High Capacity ◽  
Antagonistic Activity ◽  
Antagonistic Effect ◽  
Probiotic Potential

Background Agro-industrial waste from tropical environments could be an important source of lactic acid bacteria (LAB) with probiotic potential. Methods Twelve LAB isolates were isolated from pineapple silages. The species identification was carried out considering 16S rRNA and pheS genes. Experiments to evaluate the probiotic potential of the isolates included survival under simulated gastrointestinal environment, in vitro antagonistic activity (against Salmonella spp. and Listeria monocytogenes), auto-aggregation assays, antibiotic susceptibility, presence of plasmids, adhesiveness to epithelial cells, and antagonistic activity against Salmonella in HeLa cells. Results Lacticaseibacillus paracasei, Lentilactobacillus parafarraginis, Limosilactobacillus fermentum, and Weissella ghanensis were identified. Survival of one of the isolates was 90% or higher after exposure to acidic conditions (pH: 2), six isolates showed at least 61% survival after exposure to bile salts. The three most promising isolates, based on survivability tests, showed a strong antagonistic effect against Salmonella. However, only L. paracasei_6714 showed a strong Listeria inhibition pattern; this isolate showed a good auto-aggregation ability, was resistant to some of the tested antibiotics but was not found to harbor plasmids; it also showed a high capacity for adhesion to epithelial cells and prevented the invasion of Salmonella in HeLa cells. After further in vivo evaluations, L. paracasei_6714 may be considered a probiotic candidate for food industry applications and may have promising performance in acidic products due to its origin.

scholarly journals Antibodies to Tyvelose Exhibit Multiple Modes of Interference with the Epithelial Niche of Trichinella spiralis

2000 ◽  
Vol 68 (4) ◽  
pp. 1912-1918 ◽  
Author(s):  
Catherine S. McVay ◽  
Peter Bracken ◽  
Lucille F. Gagliardo ◽  
Judith Appleton
Keyword(s):  
Epithelial Cells ◽  
Trichinella Spiralis ◽  
In Vivo Studies ◽  
Parasite Development ◽  
Multiple Modes ◽  
Protective Antibodies ◽  
Sensory Reception ◽  
Vitro Model

ABSTRACT Infection with the parasitic nematode Trichinella spiralis is initiated when the L1 larva invades host intestinal epithelial cells. Monoclonal antibodies specific for glycans on the larval surface and secreted glycoproteins protect the intestine against infection. Protective antibodies recognize tyvelose which caps the target glycan. In this study, we used an in vitro model of invasion to further examine the mechanism(s) by which tyvelose-specific antibodies protect epithelial cells against T. spiralis. Using cell lines that vary in susceptibility to invasion, we confirmed and clarified the results of our in vivo studies by documenting three modes of interference: exclusion of larvae from cells, encumbrance of larvae as they migrated within epithelial monolayers, and inhibition of parasite development. Excluded larvae bear cephalic caps (C. S. McVay et al., Infect. Immun. 66:1941–1945, 1998) of immune complexes that may physically block invasion or may interfere with sensory reception. Monovalent Fab fragments prepared from a tyvelose-specific antibody also excluded larvae from cells, demonstrating that antibody binding can inhibit the parasite in the absence of antigen aggregation and cap formation. In contrast, encumbered larvae caused extensive damage to the monolayer yet were not successful in establishing a niche, as reflected by their failure to molt. These results show that antibodies to tyvelose exhibit multiple modes of inhibitory activity, further implicating tyvelose-bearing glycoproteins as mediators of invasion and niche establishment by T. spiralis.

scholarly journals Non-Typeable Haemophilus influenzae Invade Choroid Plexus Epithelial Cells in a Polar Fashion

2020 ◽  
Vol 21 (16) ◽  
pp. 5739
Author(s):  
Christian Wegele ◽  
Carolin Stump-Guthier ◽  
Selina Moroniak ◽  
Christel Weiss ◽  
Manfred Rohde ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Haemophilus Influenzae ◽  
Choroid Plexus ◽  
Human Respiratory Tract ◽  
Meningeal Inflammation ◽  
Invasive Infections ◽  
The Brain ◽  
Adhesion And Invasion

Non-typeable Haemophilus influenzae (NTHI) is a pathogen of the human respiratory tract causing the majority of invasive H. influenzae infections. Severe invasive infections such as septicemia and meningitis occur rarely, but the lack of a protecting vaccine and the increasing antibiotic resistance of NTHI impede treatment and emphasize its relevance as a potential meningitis causing pathogen. Meningitis results from pathogens crossing blood–brain barriers and invading the immune privileged central nervous system (CNS). In this study, we addressed the potential of NTHI to enter the brain by invading cells of the choroid plexus (CP) prior to meningeal inflammation to enlighten NTHI pathophysiological mechanisms. A cell culture model of human CP epithelial cells, which form the blood–cerebrospinal fluid barrier (BCSFB) in vivo, was used to analyze adhesion and invasion by immunofluorescence and electron microscopy. NTHI invade CP cells in vitro in a polar fashion from the blood-facing side. Furthermore, NTHI invasion rates are increased compared to encapsulated HiB and HiF strains. Fimbriae occurrence attenuated adhesion and invasion. Thus, our findings underline the role of the BCSFB as a potential entry port for NTHI into the brain and provide strong evidence for a function of the CP during NTHI invasion into the CNS during the course of meningitis.

Targeting of the β2-adrenoceptor increases nonviral gene delivery to pulmonary epithelial cells in vitro and lungs in vivo

2009 ◽  
Vol 135 (3) ◽  
pp. 234-241 ◽  
Author(s):  
Markus Elfinger ◽  
Johannes Geiger ◽  
Günther Hasenpusch ◽  
Senta Üzgün ◽  
Nathalie Sieverling ◽  
...  
Keyword(s):  
Gene Delivery ◽  
Epithelial Cells ◽  
Nonviral Gene Delivery ◽  
Pulmonary Epithelial Cells

scholarly journals Deciphering and reconstitution of positional information in the human brain development

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Yi-Fan Wang ◽  
Cong Liu ◽  
Peng-Fei Xu
Keyword(s):  
Human Brain ◽  
Neural Development ◽  
Three Dimensional ◽  
Positional Information ◽  
Physiological Level ◽  
Vitro Model ◽  
Brain Organoid ◽  
The Brain

AbstractOrganoid has become a novel in vitro model to research human development and relevant disorders in recent years. With many improvements on the culture protocols, current brain organoids could self-organize into a complicated three-dimensional organization that mimics most of the features of the real human brain at the molecular, cellular, and further physiological level. However, lacking positional information, an important characteristic conveyed by gradients of signaling molecules called morphogens, leads to the deficiency of spatiotemporally regulated cell arrangements and cell–cell interactions in the brain organoid development. In this review, we will overview the role of morphogen both in the vertebrate neural development in vivo as well as the brain organoid culture in vitro, the strategies to apply morphogen concentration gradients in the organoid system and future perspectives of the brain organoid technology.

Effect of pH and inhibitors on beta-amyloid fibril assembly

1996 ◽  
Vol 54 ◽  
pp. 752-753
Author(s):  
Beverly E. Maleeff ◽  
Timothy K. Hart ◽  
Stephen J. Wood ◽  
Ronald Wetzel
Keyword(s):  
Amyloid Fibril ◽  
Peptide Fragment ◽  
Hydrophobic Peptides ◽  
Amyloid Fibril Formation ◽  
Effects Of Ph ◽  
Severity Of The Disease ◽  
Kinetics Of ◽  
The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

Sign in / Sign up

Export Citation Format

Share Document