Effect of cholera toxin, oxygen and tissue submersion on prorenin and HCG secretion from human villous placental tissue in vitro

ABSTRACT Therapeutic vaccination is an attractive strategy to control infection and disease caused by Helicobacter pylori. In mice infected with H. pylori we have studied the protective effect of oral immunization with an H. pylori lysate preparation given together with the mucosal adjuvant cholera toxin (CT), both against the initial infection and against a later reinfection challenge. We have also examined the effects of treatment with the CT adjuvant alone on H. pylori infection and reinfection. Specific immunization with lysate was found to result in a sixfold reduction of the extent (bacterial load) of the primary infection and also to provide similar levels of protection against reinfection. However, these effects were associated with severe postimmunization gastritis. In contrast, oral treatment with CT alone at the time of initial infection, while unable to suppress the initial infection, gave rise to a 20-fold reduction in bacterial load upon reinfection without causing any associated gastric inflammation. Both the infected animals that were specifically immunized and those that were treated with CT only displayed increased in vitro proliferative responses of mononuclear cells to H. pylori antigens. Antibody levels in response to H. pylori were on the other hand only marginally increased after treatment with CT, whereas they were markedly elevated after immunization with lysate plus CT, with a rise in both (Th2-driven) immunoglobulin G1 (IgG1) and, especially, (Th1-driven) IgG2a antibodies. The results illustrate the complex balance between protection and harmful inflammation after postinfection vaccination against H. pylori as studied in a mouse model.

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Inhibition by cholera toxin of rat polymorphonuclear leukocyte chemotaxis demonstrated in vitro and in vivo.

Infection and Immunity ◽

10.1128/iai.25.1.187-190.1979 ◽

1979 ◽

Vol 25 (1) ◽

pp. 187-190 ◽

Cited By ~ 5

Author(s):

M Roch-Arveiller ◽

P Boquet ◽

D Bradshaw ◽

J P Giroud

Keyword(s):

Cholera Toxin ◽

Polymorphonuclear Leukocyte ◽

Leukocyte Chemotaxis

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Human tissue mast cells are an inducible reservoir of persistent HIV infection

Blood ◽

10.1182/blood-2006-11-058438 ◽

2007 ◽

Vol 109 (12) ◽

pp. 5293-5300 ◽

Cited By ~ 62

Author(s):

J. Bruce Sundstrom ◽

Jane E. Ellis ◽

Gregory A. Hair ◽

Arnold S. Kirshenbaum ◽

Dean D. Metcalfe ◽

...

Keyword(s):

Mast Cells ◽

Highly Active Antiretroviral Therapy ◽

Mononuclear Cells ◽

Tissue Injury ◽

Allergic Inflammation ◽

Placental Tissue ◽

Latently Infected ◽

Tissue Compartments

AbstractWe have proposed that, unlike other HIV-vulnerable cell lineages, progenitor mast cells (prMCs), cultured in vitro from undifferentiated bone marrow–derived CD34+ pluripotent progenitors (PPPs), are susceptible to infection during a limited period of their ontogeny. As infected prMCs mature in culture, they lose expression of viral chemokine coreceptors necessary for viral entry and develop into long-lived, latently infected mature tissue mast cells (MCs), resistant to new infection. In vivo recruitment of prMCs to different tissue compartments occurs in response to tissue injury, growth, and remodeling or allergic inflammation, allowing populations of circulating and potentially HIV-susceptible prMCs to spread persistent infection to diverse tissue compartments. In this report, we provide in vivo evidence to confirm this model by demonstrating that HIV-infected women have both circulating prMCs and placental tissue MCs (PLMCs) that harbor inducible infectious HIV even after highly active antiretroviral therapy (HAART) during pregnancy. Furthermore, infectious virus, capable of infecting alloactivated fetal cord blood mononuclear cells (CBMCs), could be induced in isolated latently infected PLMCs after weeks in culture in vitro. These data provide the first in vivo evidence that tissue MCs, developed from infected circulating prMCs, comprise a long-lived inducible reservoir of persistent HIV in infected persons during HAART.

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Effect of dimethyl sulfoxide on human carcinoma cells, inhibition of plasminogen activator synthesis, change in cell morphology, and alteration of response to cholera toxin.

Molecular and Cellular Biology ◽

10.1128/mcb.5.12.3552 ◽

1985 ◽

Vol 5 (12) ◽

pp. 3552-3559 ◽

Cited By ~ 12

Author(s):

L Ossowski ◽

D Belin

Keyword(s):

Dimethyl Sulfoxide ◽

Cholera Toxin ◽

Plasminogen Activator ◽

Cell Morphology ◽

Control Level ◽

Metastatic Potential ◽

Inhibitory Effect ◽

Human Carcinoma ◽

Enhanced Production

Human carcinoma HEp-3 lost its tumorigenic and metastatic potential upon prolonged culture in vitro. This change was accompanied by a reduced production of plasminogen activator (PA) of the urokinase type (uPA), which is secreted by HEp-3 cells, a change in response to effectors that modulate uPA production, and an alteration of cell morphology. Similar but more rapid changes occurred when malignant HEp-3 cells were exposed to dimethyl sulfoxide (DMSO). uPA activity in the culture medium dropped below 50% of the control level within 6 h after the addition of DMSO and became undetectable after 24 h of treatment. This drop in uPA activity was not caused by an increased production of PA inhibitors. The cell-associated uPA decreased to 25 to 30% of the control level within 6 h of DMSO treatment and remained at this level for at least 96 h; the reduced uPA production was partially accounted for by a rapid decrease in the functional and chemical concentration of uPA mRNA. In contrast, the concentrations of most of the abundant mRNA species did not appear to be significantly affected, and cell growth was only slightly inhibited in the presence of DMSO. Malignant HEp-3 cells treated with DMSO responded to cholera toxin with an enhanced production of uPA, and their morphology became indistinguishable from that of nonmalignant HEp-3 cells grown in vitro for prolonged periods of time. All of the above changes were fully and rapidly reversible. The inhibitory effect of DMSO on PA production appears to be specific for uPA of human cell lines.

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Abstract 207: C-Reactive Protein Signaling via Neurokinin B Receptor Contributes to the Pathophysiology of Preeclampsia

Hypertension ◽

10.1161/hyp.60.suppl_1.a207 ◽

2012 ◽

Vol 60 (suppl_1) ◽

Author(s):

Nicholas Parchim ◽

Wei Wang ◽

Chen Liu ◽

Athar Siddiqui ◽

Rodney Kellems ◽

...

Keyword(s):

Placental Tissue ◽

Protein Signaling ◽

Post Translational Modification ◽

C Reactive Protein ◽

Neurokinin B ◽

Bacterial Membranes ◽

Reactive Protein ◽

Nk3 Receptor ◽

Invasion Index

Introduction: C-Reactive Protein (CRP) is an important immunomodulatory molecule. Early studies have indicated that CRP is elevated in preeclamptic patient sera, but its function remains unclear. CRP is known to bind with phosphocholine (PC) of bacteria membrane to kill bacteria by triggering innate immune response. Phosphocholination is a post-translational modification mediated by PC transferase, an enzyme reported expressed only in two tissues, including placenta and testis. Recent studies identified that Neurokinin B (NKB), a known, placenta-enriched pathogenic molecule for preeclampsia (PE), is phosphocholinated. This modification increases its stability, preferentially activates NK3 receptor (NK3R) and promotes PE features. Given CRP can bind to PC on bacterial membranes, the role that phosphocholination plays is a mystery. In light of NKB, being phosphocholinated in the endoplasmic reticulum and signals via the NK3R in the pathogenesis of PE, we feel that elevated CRP may be associated with NKB and contributes to the pathophysiology of PE via NK3R activation. Results: ELISA results show that CRP is significantly elevated in PE vs. control sera_65 ug/mL vs. 10 ug/ml; p<0.0001. Western blot analysis reveals that CRP, NKB, and NK3R are significantly increased in PE vs. control placental tissue. Immunohistochemistry studies indicate that all of these three molecules are abundant in syncytiotrophoblast cells. Co-immunoprecipitation demonstrates an interaction between CRP and NKB. In vitro , we provide the first evidence that CRP decreased the invasion of trophoblast cells from 0.7 ± 0.06 to 0.06 ± 0.001 invasion index; p<0.005, while treatment with SB222200 ameliorates shallow invasion from 0.28 ± 0.09 to 0.55 ± 0.07 invasion index; p<0.05. Significantly, infusion of CRP into pregnant mice induces hypertension (169.152 ± 14.7 mmHg vs. 141.916 ± 6.93 mmHg; p<0.05) and proteinuria (28.78 ± 13.56 mg albumin/μg Cr vs. 13.87 ± 3.277 mg albumin/μg Cr; p<0.05). Conclusion: Our findings demonstrate elevated CRP contributes to PE and NKB/NK3R is a new mechanism underlying CRP-mediated shallow invasion and disease development. These studies suggest novel pathogenic biomarkers and innovative therapies for PE.

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Chloroquine stimulates absorption and inhibits secretion of ileal water and electrolytes

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1982.243.2.g117 ◽

1982 ◽

Vol 243 (2) ◽

pp. G117-G126

Author(s):

R. Fogel ◽

G. W. Sharp ◽

M. Donowitz

Keyword(s):

Cholera Toxin ◽

Calcium Content ◽

Intracellular Camp ◽

Rabbit Ileum ◽

Camp Content ◽

Serosal Surface ◽

Ileal Absorption ◽

Camp Levels

The effects of chloroquine diphosphate, a drug with "'membrane-stabilizing" properties, were studied on basal ileal absorption and on ileal secretion induced by increased intracellular cAMP levels and calcium (serotonin). The studies were performed on rat (in vivo) and rabbit ileum (in vitro). Intraluminal chloroquine (10(-4) M) reversed cholera toxin- and theophylline-induced secretion in rat ileum but did not alter the cholera toxin- and theophylline-induced increases in cAMP content. Addition of chloroquine (10(-4) M) to the mucosal surface of rabbit ileum did not alter basal active electrolyte transport or the serotonin-induced decreased Na and Cl absorption but inhibited the theophylline-induced C1 secretion. Addition of chloroquine (10(-4)) M) to the serosal surface stimulated net Na and Cl absorption. This effect may involve intracellular calcium. Chloroquine increased the rabbit ileal calcium content and decreased 45Ca2+ influx from the serosal surface. Both the mucosal and serosal effects of chloroquine described led to a net increase in absorptive function of the intestine and should prove useful in developing treatment of diarrheal diseases.

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