scholarly journals Analysis of Cytokines in the Early Development of Gastric Secondary Lymphoid Follicles in Helicobacter pylori-Infected BALB/c Mice with Neonatal Thymectomy

2001 ◽  
Vol 69 (11) ◽  
pp. 6749-6754 ◽  
Author(s):  
Kazushige Uchida ◽  
Kazuichi Okazaki ◽  
Andras Debrecceni ◽  
Toshiki Nishi ◽  
Hirosi Iwano ◽  
...  

ABSTRACT Immunological interaction between the host and Helicobacter pylori seems to play a critical role in follicular formation in gastric mucosa. We reported H. pylori-induced follicular gastritis model using neonatally thymectomized mice. In this study, we investigated the involvement of various cytokines in this model. BALB/c mice were thymectomized on the third day after birth (nTx). At 6 weeks old, these mice were orally infected with H. pylori. Histological studies showed that follicular formation occurred from 8 weeks after the infection and that most of the infiltrating lymphocytes were CD4+ and B cells. Neutrophils increased transiently at 1 week after the infection. Gamma interferon, interleukin-7 (IL-7), and IL-7 receptor were expressed in the stomach of the nTx mice irrespective of the infection. In contrast, expressions of the tumor necrosis factor alpha, IL-4 and lymphotoxin-α genes were remarkably upregulated by the infection. Our findings suggest that follicular formation may require cooperative involvement of a Th2-type immune response, tumor necrosis factor alpha and lymphotoxin-α in addition to the Th1-type immune response in H. pylori-induced gastritis in nTx mice.

2017 ◽  
Vol 85 (6) ◽  
Author(s):  
Shannon L. Donahoe ◽  
David N. Phalen ◽  
Bronwyn M. McAllan ◽  
Denis O'Meally ◽  
Milton M. McAllister ◽  
...  

ABSTRACT Toxoplasma gondii and Neospora caninum (both Apicomplexa) are closely related cyst-forming coccidian parasites that differ significantly in their host ranges and ability to cause disease. Unlike eutherian mammals, Australian marsupials (metatherian mammals) have long been thought to be highly susceptible to toxoplasmosis and neosporosis because of their historical isolation from the parasites. In this study, the carnivorous fat-tailed dunnart (Sminthopsis crassicaudata) was used as a disease model to investigate the immune response and susceptibility to infection of an Australian marsupial to T. gondii and N. caninum. The disease outcome was more severe in N. caninum-infected dunnarts than in T. gondii-infected dunnarts, as shown by the severity of clinical and histopathological features of disease and higher tissue parasite burdens in the tissues evaluated. Transcriptome sequencing (RNA-seq) of spleens from infected dunnarts and mitogen-stimulated dunnart splenocytes was used to define the cytokine repertoires. Changes in mRNA expression during the time course of infection were measured using quantitative reverse transcription-PCR (qRT-PCR) for key Th1 (gamma interferon [IFN-γ] and tumor necrosis factor alpha [TNF-α]), Th2 (interleukin 4 [IL-4] and IL-6), and Th17 (IL-17A) cytokines. The results show qualitative differences in cytokine responses by the fat-tailed dunnart to infection with N. caninum and T. gondii. Dunnarts infected with T. gondii were capable of mounting a more effective Th1 immune response than those infected with N. caninum, indicating the role of the immune response in the outcome scenarios of parasite infection in this marsupial mammal.


1998 ◽  
Vol 72 (12) ◽  
pp. 9514-9525 ◽  
Author(s):  
Karim Benihoud ◽  
Isabella Saggio ◽  
Paule Opolon ◽  
Barbara Salone ◽  
Franck Amiot ◽  
...  

ABSTRACT The efficiency of adenovirus-mediated gene transfer is now well established. However, the cellular and the humoral immune responses triggered by vector injection lead to the rapid elimination of the transduced cells and preclude any efficient readministration. The present investigation focuses on the role of tumor necrosis factor alpha (TNF-α), a proinflammatory cytokine, and the related cytokine lymphotoxin α (LTα), in mounting an immune reaction against recombinant adenovirus vectors. After gene transfer in the liver, mice genetically deficient for both cytokines (TNF-α/LTα−/−), in comparison with normal mice, presented a weak acute-phase inflammatory reaction, a reduction in cellular infiltrates in the liver, and a severely impaired T-cell proliferative response to both Adenoviral and transgene product antigens. Moreover, we observed a strong reduction in the humoral response to the vector and the transgene product, with a drastic reduction of anti-adenovirus immunoglobulin A and G antibody isotypes. In addition, the reduction in antibody response observed in TNF-α/LTα−/− and TNF-α/LTα+/− mice versus TNF-α/LTα+/+ mice links antibody levels to TNF-α/LTα gene dosage. Due to the absence of neutralizing antibodies, the TNF-α/LTα knockout mice successfully express a second gene transduced by a second vector injection. The discovery of the pivotal role played by TNF-α in controlling the antibody response against adenovirus will allow more efficient adenovirus-based strategies for gene therapy to be proposed.


2020 ◽  
Author(s):  
Shweta Mahant ◽  
Shubham Mehra ◽  
Ayushi Chhawchharia ◽  
Bipul Chandra Karmakar ◽  
Sangita Paul ◽  
...  

Abstract Background: Helicobacter pylori (H. pylori) is known to cause several gastro-duodenal diseases including chronic Gastritis, Peptic Ulcer disease and Gastric Cancer. Virulent genes of H. pylori like cagA, vacA are known to be responsible for the disease pathogenesis. But these virulence genes are not always found to be associated with disease outcome in all populations around the world. Relationship of H. pylori with Gastro Esophageal Reflux Diseases is controversial and uncertain. Tumor necrosis factor alpha inducing protein tipα is a new discovered virulent gene of H. pylori and is an inducer of certain cytokines and chemokines that are responsible for causing stomach cancer. Therefore, we conducted a study which aims to find the prevalence of tipα gene in the Indian population and its association with H. pylori related upper gastrointestinal diseases.Results: 267 clinical H. pylori isolates are included in our study for finding the prevalence of tipα gene and its association with cagA and vacA gene using PCR assay. The current study shows the prevalence rate of tipα gene in the Indian population to be 59.9%. Our study has found a significant association (p < 0.05) of tipα gene with Non Ulcer Dyspepsia (NUD) and also an association of cagA and vacA s1m1 with Gastritis and Duodenal Ulcer.Conclusion: Our study demonstrates for the first time the presence of tipα as virulent factor of H. pylori strain in Indian population isolated from patients suffering from upper gastrointestinal diseases. Further, tipα is significantly associated with NUD but not with other upper gastrointestinal diseases in India.


2002 ◽  
Vol 70 (6) ◽  
pp. 3149-3155 ◽  
Author(s):  
Ulrike Thalmaier ◽  
Norbert Lehn ◽  
Klaus Pfeffer ◽  
Manfred Stolte ◽  
Michael Vieth ◽  
...  

ABSTRACT Increased gastric production of interleukin 8 and tumor necrosis factor alpha (TNF-α) has been implicated in the pathogenesis of Helicobacter pylori-associated gastroduodenal disease. In the present study we used a mouse model to demonstrate whether loss of the tumor necrosis factor receptor 1 (TNF-R1) function leads to differences in gastric inflammation or the systemic immune response in H. pylori infection. Six different clinical isolates of H. pylori (three cytotoxin-positive and three cytotoxin-negative strains) were adapted to C57BL/6 mice. TNF-R1-deficient (TNF-R1−/−) mice (n = 19) and isogenetic controls (n = 24) were infected and sacrificed after 4 weeks of infection. Inflammation of the stomach and the humoral immune response to H. pylori were evaluated by histological, immunohistochemical, and serological methods. There was no detectable difference in the grade or activity of gastritis in TNF-R1−/− mice when they were compared with wild-type mice, but the number of lymphoid aggregates was slightly reduced in the gastric mucosa of TNF-R1−/− mice. Interestingly, total immunoglobulin G (IgG), as well as IgG1, IgG2b, and IgG3, H. pylori-specific antibody titers were significantly higher in wild-type mice. As revealed by immunoblot analysis, the difference in reactivity against H. pylori antigens was not based on a failure to recognize single H. pylori antigens in TNF-R1−/− mice. We therefore suggest that TNF-R1-mediated TNF-α signals might support a systemic humoral immune response against H. pylori and that the gastric inflammatory response to H. pylori infection seems to be independent of TNF-R1-mediated signals.


2001 ◽  
Vol 69 (6) ◽  
pp. 3980-3988 ◽  
Author(s):  
Basel K. al-Ramadi ◽  
Mariam H. Al-Dhaheri ◽  
Nada Mustafa ◽  
Mounir AbouHaidar ◽  
Damu Xu ◽  
...  

ABSTRACT Attenuated Salmonella strains are of interest as new vaccine candidates and as vectors of cloned genes of other organisms. Attenuated strains expressing specific cytokines were constructed as a means of manipulating the immune response in various disease settings. In the present study, interleukin-2 (IL-2)-expressing (GIDIL2) or tumor necrosis factor alpha (TNF-α)-expressing (GIDTNF) strains were compared with the parent strain (BRD509) for the effect of cytokines on anti-Salmonella immunity. Expression of IL-2 resulted in a rapid clearance of the organism soon after vaccination. The reduction in GIDIL2 CFU was 50- to 300-fold higher than that of BRD509 and correlated with a markedly decreased splenomegaly. Furthermore, no evidence for any significant activation, including upregulation of surface markers and production of nitric oxide (NO), was observed in spleens of GIDIL2-injected mice. In contrast, the host response to GIDTNF was marked by an early, strong, splenic cellular influx, but surprisingly, the degree of induced splenomegaly and NO secretion was only 50% of that observed in BRD509-treated mice. Despite this, bacterial colonization of the spleen in GIDTNF-immunized animals was either slightly decreased from or equivalent to that of the BRD509-treated group, suggesting the induction of additional antimicrobial mechanisms by TNF-α. In vivo protection studies demonstrated that, at limiting doses, GIDIL2 was inferior to GIDTNF and BRD509 in its capacity to protect against virulent challenge. At high doses, however, all three strains exhibited equal protective efficacy. These results demonstrate that the immune response against intracellular bacteria can be manipulated by pathogen-expressed cytokines and open the way for further fine tuning of immune responses not only to Salmonella strains themselves but also to the heterologous gene(s) carried by them.


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