scholarly journals Early Lesions of Proliferative Enteritis in Pigs and Hamsters

1989 ◽  
Vol 26 (3) ◽  
pp. 260-264 ◽  
Author(s):  
S. McOrist ◽  
G. H. K. Lawson ◽  
A. C. Rowland ◽  
N. MacIntyre
Keyword(s):  
Life Cycle ◽  
Intestinal Lumen ◽  
Intracellular Bacteria ◽  
Immunogold Staining ◽  
Specific Antibodies ◽  
Early Lesions ◽  
Membrane Bound ◽  
Gnotobiotic Pigs ◽  
Intracellular Multiplication ◽  
Marked Proliferation

Gnotobiotic pigs and conventional hamsters were given suspensions of intestinal mucosa from a pig with proliferative hemorrhagic enteropathy and killed 10 or 21 days later. Affected animals had evidence of marked proliferation of immature enterocytes in the intestinal crypts. Numerous Campylobacter-like organisms were in the cytoplasm of enterocytes, and in some instances, bacteria were closely associated with enter-ocytes. Some intracellular bacteria lying below the microvillous border were within membrane-bound structures. Immunofluorescence and electron immunogold staining with specific antibodies indicated that these organisms were antigenically different from curved bacteria in the crypt lumen of early lesions. This study indicates that the life cycle of the intracellular organisms may involve entry into crypt enterocytes from the intestinal lumen with subsequent intracellular multiplication.

Membrane-Bound Sperm-Specific Antibodies: Their Role in Infertility

1981 ◽  
pp. 521-527 ◽  
Author(s):  
RICHARD BRONSON ◽  
GEORGE COOPER ◽  
DAVID L. ROSENFELD
Keyword(s):  
Specific Antibodies ◽  
Membrane Bound

Localisation of two classes of acetylcholine receptor-like molecules in sperms of different animal species

Zygote ◽  
1995 ◽  
Vol 3 (3) ◽  
pp. 207-217 ◽  
Author(s):  
B. Baccetti ◽  
A.G. Burrini ◽  
G. Collodel ◽  
C. Falugi ◽  
E. Moretti ◽  
...  
Keyword(s):  
Nicotinic Receptor ◽  
Nicotinic Receptors ◽  
Animal Species ◽  
Distribution Patterns ◽  
Sperm Head ◽  
Similar Distribution ◽  
Vertebrate Species ◽  
Immunogold Staining ◽  
Specific Antibodies ◽  
Transduction Mechanisms

SummaryThe distribution of different classes of acetylcholine (ACh) receptor-like molecules in sperms of different invertebrate and vertebrate species is described. ACh receptor molecules belong to one of two classes: muscarinic receptors (mAChRs), associated with signal transduction mechanisms in the inner domain of the cell, and nicotinic receptors (nAChRs), capable of opening Na+ channels when activated by the ligand. Molecules immunologically related to mAChRs and to ACh can be identified by specific antibodies, and revealed by immunofluorescent or immunogold staining; the nicotinic receptor-like molecules are localised as curare-sensitive affinity sites for α-bungarotoxin. In all species studied, both classes of receptors were found, with a similar distribution. Muscarinic-like molecules were found mainly in the sperm head regions of most species; such a localisation may be correlated to a function in sperm–egg interaction, for instance in the regulation of the block to polyspermy. Nicotinic-like molecules are present mainly in the tail and in the post-acrosomal region of most animals, thus confirming their function in the regulation of sperm propulsion, but are also present at the acrosomal region of most species. The distribution patterns of the different classes of molecules indicate that both may be in sperm–egg interactions, in addition to their known function in the regulation of sperm propulsion.

scholarly journals Feline infectious peritonitis virus-infected monocytes internalize viral membrane-bound proteins upon antibody addition

2006 ◽  
Vol 87 (6) ◽  
pp. 1685-1690 ◽  
Author(s):  
Hannah L. Dewerchin ◽  
Els Cornelissen ◽  
Hans J. Nauwynck
Keyword(s):  
Viral Proteins ◽  
Cell Type Specificity ◽  
Feline Infectious Peritonitis Virus ◽  
Feline Infectious Peritonitis ◽  
Specific Antibodies ◽  
Humoral Immune ◽  
Dependent Cell ◽  
Infected Cells ◽  
Membrane Bound ◽  
In Cells

Feline infectious peritonitis virus (FIPV) may cause a highly lethal infection in cats, in spite of a usually strong humoral immune response. Antibodies seem unable to identify infected cells and mediate antibody-dependent cell lysis. In this study, the effect of antibodies on Feline coronavirus (FCoV)-infected monocytes was investigated. Upon addition of FCoV-specific antibodies, surface-expressed viral proteins were internalized through a highly efficient process, resulting in cells without visually detectable viral proteins on their plasma membrane. The internalization was also induced by mAbs against the Spike and Membrane proteins, suggesting that both proteins play a role in the process. The internalization did not occur spontaneously, as it was not observed in cells incubated with medium or non-specific antibodies. Further, the internalization could not be reproduced in feline cell lines, indicating its cell-type specificity. This study sheds new light on the immune-evasive nature of FIPV infections.

scholarly journals Rapid Protection of Gnotobiotic Pigs against Experimental Salmonellosis following Induction of Polymorphonuclear Leukocytes by Avirulent Salmonella enterica

2003 ◽  
Vol 71 (4) ◽  
pp. 2182-2191 ◽  
Author(s):  
N. Foster ◽  
M. A. Lovell ◽  
K. L. Marston ◽  
S. D. Hulme ◽  
A. J. Frost ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Clinical Symptoms ◽  
Invasive Disease ◽  
Polymorphonuclear Neutrophils ◽  
Intestinal Lumen ◽  
Epithelial Cell Line ◽  
Intestinal Pathology ◽  
Serovar Typhimurium ◽  
Gnotobiotic Pigs

ABSTRACT Oral inoculation of 5-day-old gnotobiotic pigs with Salmonella enterica serovar Typhimurium strain F98 resulted in severe enteritis and invasive disease. Preinoculation 24 h earlier with an avirulent mutant of Salmonella enterica serovar Infantis (1326/28) completely prevented disease for up to 14 days (when the experiment was terminated). S. enterica serovar Infantis colonized the alimentary tract well, with high bacterial counts in the intestinal lumen but with almost no invasion into the tissues. Unprotected pigs had high S. enterica serovar Typhimurium counts in the intestines, blood, and major nonintestinal organs. Recovery of this strain from the blood and major organs in S. enterica serovar Infantis-protected pigs was substantially reduced despite the fact that intestinal counts were also very high. Protection against disease thus did not involve a colonization exclusion phenomenon. Significant (P < 0.05) infiltration of monocytes/macrophages was observed in the submucosal regions of the intestines of both S. enterica serovar Infantis-protected S. enterica serovar Typhimurium-challenged pigs and unprotected S. enterica serovar Typhimurium-challenged pigs. However, only polymorphonuclear neutrophils (PMNs) were observed throughout the villus, where significant (P < 0.05) numbers infiltrated the lamina propria and the subnuclear and supranuclear regions of the epithelia, indicating that PMN induction and positioning following S. enterica serovar Infantis inoculation was consistent with rapid protection against the challenge strain. Similarly, in vitro experiments using a human fetal intestinal epithelial cell line (INT 407) demonstrated that, although significantly (P < 0.05) fewer S. enterica serovar Infantis than S. enterica serovar Typhimurium organisms invaded the monolayers, S. enterica serovar Infantis induced an NF-κB response and significantly (P < 0.05) raised interleukin 8 levels and transmigration of porcine PMN. The results of this study suggest that attenuated Salmonella strains can protect the immature intestine against clinical salmonellosis by PMN induction. They also demonstrate that PMN induction is not necessarily associated with clinical symptoms and/or intestinal pathology.

scholarly journals Murine Typhus: Clinical and epidemiological aspects

2012 ◽  
pp. 175-180 ◽  
Author(s):  
Gaspar Peniche Lara ◽  
Karla R. Dzul Rosado ◽  
Jorge Ernesto Zavala Velásquez ◽  
Jorge Zavala-Castro
Keyword(s):  
Dengue Fever ◽  
High Frequency ◽  
Relevant Information ◽  
Intracellular Bacteria ◽  
Murine Typhus ◽  
Rickettsia Typhi ◽  
Specific Antibodies ◽  
Xenopsylla Cheopis ◽  
Organ Specific

Rickettsia typhi is an intracellular bacteria who causes murine typhus. His importance is reflected in the high frequency founding specific antibodies against R. typhi in several worldwide seroepidemiological studies, the seroprevalence ranging between 3-36%. Natural reservoirs of Rickettsia typhi are rats (some species belonging the Rattus Genus) and fleas (Xenopsylla cheopis) are his vector. This infection is associated with overcrowding, pollution and poor hygiene. Typically presents fever, headache, rash on trunk and extremities, in some cases may occur organ-specific complications, affecting liver, kidney, lung or brain. Initially the disease is very similar to other diseases, is very common to confuse the murine typhus with Dengue fever, therefore, ignorance of the disease is a factor related to complications or non-specific treatments for the resolution of this infection. This paper presents the most relevant information to consider about the rickettsiosis caused by Rickettsia typhi.

scholarly journals Humans surviving cholera develop antibodies against Vibrio cholerae O-specific polysaccharide that inhibit pathogen motility

2020 ◽  
Author(s):  
Richelle C. Charles ◽  
Meagan Kelly ◽  
Jenny M. Tam ◽  
Aklima Akter ◽  
Motaher Hossain ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Vibrio Cholerae ◽  
Polyclonal Antibody ◽  
High Speed ◽  
Polyclonal Antibodies ◽  
Intestinal Lumen ◽  
Dependent Manner ◽  
Specific Antibodies ◽  
Specific Polysaccharide

ABSTRACTThe mechanism of protection against cholera afforded by previous illness or vaccination is currently unknown. We have recently shown that antibodies targeting O-specific polysaccharide (OSP) of Vibrio cholerae correlate highly with protection against cholera. V. cholerae is highly motile and possesses a flagellum sheathed in O-specific polysaccharide (OSP), and motility of V. cholerae correlates with virulence. Using high speed video microscopy, and building upon previous animal-related work, we demonstrate that sera, polyclonal antibody fractions, and OSP-specific monoclonal antibodies recovered from humans surviving cholera block V. cholerae motility at both subagglutinating and agglutinating concentrations. This anti-motility effect is reversed by pre-adsorbing sera and polyclonal antibody fractions with purified OSP; and is associated with OSP-specific but not flagellin-specific monoclonal antibodies. F[ab] fragments of OSP-specific polyclonal antibodies do not inhibit motility, suggesting a requirement for antibody-mediated crosslinking in motility inhibition. We show that OSP-specific antibodies do not directly affect V. cholerae viability, but that OSP-specific monoclonal antibody highly protects against death in the murine cholera model. We used in vivo competitive index studies to demonstrate that OSP-specific antibodies impede colonization and survival of V. cholerae in intestinal tissues, and that this impact is motility-dependent. Our findings suggest that the impedance of motility by antibodies targeting V. cholerae OSP contributes to protection against cholera.IMPORTANCECholera is a severe dehydrating illness of humans caused by Vibrio cholerae. V. cholerae is a highly motile bacterium that has a single flagellum covered in lipopolysaccharide (LPS) displaying O-specific polysaccharide (OSP), and V. cholerae motility correlates with its ability to cause disease. The mechanisms of protection against cholera are not well understood; however, since V. cholerae is a non-invasive intestinal pathogen, it is likely that antibodies that bind the pathogen or its products in the intestinal lumen contribute to protection from infection. Here, we demonstrate that OSP-specific antibodies isolated from humans surviving cholera in Bangladesh inhibit V. cholerae motility and are associated with protection against challenge in a motility-dependent manner.

scholarly journals Loss of the Plasma Membrane-Bound Protein Gas1p inSaccharomyces cerevisiae Results in the Release of β1,3-Glucan into the Medium and Induces a Compensation Mechanism To Ensure Cell Wall Integrity

1998 ◽  
Vol 180 (6) ◽  
pp. 1418-1424 ◽  
Author(s):  
Arthur F. J. Ram ◽  
Johan C. Kapteyn ◽  
Roy C. Montijn ◽  
L. Heleen P. Caro ◽  
Jeroen E. Douwes ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Wall Protein ◽  
Compensation Mechanism ◽  
Cell Integrity ◽  
Glucan Synthase ◽  
Specific Antibodies ◽  
Enhanced Expression ◽  
Membrane Bound ◽  
Compensatory Reactions ◽  
Spherical Cells

ABSTRACT Deletion of GAS1/GGP1/CWH52 results in a lower β-glucan content of the cell wall and swollen, more spherical cells (L. Popolo, M. Vai, E. Gatti, S. Porello, P. Bonfante, R. Balestrini, and L. Alberghina, J. Bacteriol. 175:1879–1885, 1993; A. F. J. Ram, S. S. C. Brekelmans, L. J. W. M. Oehlen, and F. M. Klis, FEBS Lett. 358:165–170, 1995). We show here that gas1Δ cells release β1,3-glucan into the medium. Western analysis of the medium proteins with β1,3-glucan- and β1,6-glucan-specific antibodies showed further that at least some of the released β1,3-glucan was linked to protein as part of a β1,3-glucan–β1,6-glucan–protein complex. These data indicate that Gas1p might play a role in the retention of β1,3-glucan and/or β-glucosylated proteins. Interestingly, the defective incorporation of β1,3-glucan in the cell wall was accompanied by an increase in chitin and mannan content in the cell wall, an enhanced expression of cell wall protein 1 (Cwp1p), and an increase in β1,3-glucan synthase activity, probably caused by the induced expression of Fks2p. It is proposed that the cell wall weakening caused by the loss of Gas1p induces a set of compensatory reactions to ensure cell integrity.

scholarly journals The Immunogenicity of the Tumor-Associated Antigenα-Fetoprotein Is Enhanced by a Fusion with a Transmembrane Domain

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Lucile Tran ◽  
Jean-Paul Judor ◽  
Vanessa Gauttier ◽  
Michel Geist ◽  
Chantal Hoffman ◽  
...  
Keyword(s):  
Immune Response ◽  
Elispot Assay ◽  
Transmembrane Domain ◽  
T Cell Response ◽  
Antibody Detection ◽  
Specific Antibodies ◽  
Intracellular Form ◽  
Modified Vaccinia Virus Ankara ◽  
Membrane Bound ◽  
Self Antigen

Aim. To investigate the ability of recombinant modified vaccinia virus Ankara (rMVA) vector to induce an immune response against a well-tolerated self-antigen.Methods. rMVA vectors expressing different form ofα-fetoprotein (AFP) were produced and characterized. Naïve mice were vaccinated with MVA vectors expressing the AFP antigen in either a secreted, or a membrane-bound, or an intracellular form. The immune response was monitored by an IFNΓ ELISpot assay and antibody detection.Results. Vaccination with the membrane-associated form of AFP induced a stronger CD8+T-cell response compared to the ones obtained with the MVA encoding the secreted or the intracellular forms of AFP. Moreover, the vaccination with the membrane-bound AFP elicited the production of AFP-specific antibodies.Conclusions. The AFP transmembrane form is more immunogenic. Expressing a membrane-bound form in the context of an MVA vaccination could enhance the immunogenicity of a self-antigen.

scholarly journals New intranuclear symbiotic bacteria from macronucleus of Paramecium putrinum — Candidatus Gortzia yakutica

2020 ◽  
Author(s):  
Alexandra Beliavskaia ◽  
Maria Logacheva ◽  
Sofya Garushyants ◽  
Jun Gong ◽  
Songbao Zou ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Life Cycle ◽  
Ssu Rdna ◽  
Symbiotic Bacteria ◽  
Intracellular Bacteria ◽  
Obligate Intracellular ◽  
Strict Specificity ◽  
A New Species ◽  
Significant Attention

AbstractHolospora-like bacteria are obligate intracellular Alphaproteobacteria, inhabiting nuclei of Paramecium ciliates and other protists. Alphaproteobacteria have drawn significant attention, as both closest existing relatives of bacteria that gave rise to mitochondria, as well as a class of intracellular bacteria with numerous important pathogens.HLB clade includes two genera – Holospora (Hafkine 1980) and candidatus Gortzia (Boscaro 2013). These bacteria have a peculiar life cycle with two morphological forms, a strict specificity to the host species and the type of nucleus they inhabit.Here we describe a new species of HLB – candidatus Gortzia yakutica sp. nov., a symbiont from macronucleus of Paramecium putrinum, the first known HLB for this Paramecium species. The new symbiont shows morphological similarities with other HLB. The phylogenetic analysis of SSU rDNA gene places it into candidatus Gortzia clade.

scholarly journals Coronavirus RNA Synthesis Takes Place within Membrane-Bound Sites

Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2540
Author(s):  
Nicole Doyle ◽  
Jennifer Simpson ◽  
Philippa C. Hawes ◽  
Helena J. Maier
Keyword(s):  
Life Cycle ◽  
Infectious Bronchitis Virus ◽  
Rna Synthesis ◽  
Rna Viruses ◽  
Viral Rna ◽  
Host Cells ◽  
Infectious Bronchitis ◽  
Welfare Issue ◽  
Membrane Bound ◽  
Positive Strand Rna

Infectious bronchitis virus (IBV), a gammacoronavirus, is an economically important virus to the poultry industry, as well as a significant welfare issue for chickens. As for all positive strand RNA viruses, IBV infection causes rearrangements of the host cell intracellular membranes to form replication organelles. Replication organelle formation is a highly conserved and vital step in the viral life cycle. Here, we investigate the localization of viral RNA synthesis and the link with replication organelles in host cells. We have shown that sites of viral RNA synthesis and virus-related dsRNA are associated with one another and, significantly, that they are located within a membrane-bound compartment within the cell. We have also shown that some viral RNA produced early in infection remains within these membranes throughout infection, while a proportion is trafficked to the cytoplasm. Importantly, we demonstrate conservation across all four coronavirus genera, including SARS-CoV-2. Understanding more about the replication of these viruses is imperative in order to effectively find ways to control them.

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