scholarly journals Cytokine Profiles in Malawian Children Presenting with Uncomplicated Malaria, Severe Malarial Anemia, and Cerebral Malaria

2017 ◽  
Vol 24 (4) ◽  
Author(s):  
Wilson L. Mandala ◽  
Chisomo L. Msefula ◽  
Esther N. Gondwe ◽  
Mark T. Drayson ◽  
Malcolm E. Molyneux ◽  
...  

ABSTRACT Proinflammatory cytokines are involved in clearance of Plasmodium falciparum, and very high levels of these cytokines have been implicated in the pathogenesis of severe malaria. In order to determine how cytokines vary with disease severity and syndrome, we enrolled Malawian children presenting with cerebral malaria (CM), severe malarial anemia (SMA), and uncomplicated malaria (UCM) and healthy controls. We analyzed serum cytokine concentrations in acute infection and in convalescence. With the exception of interleukin 5 (IL-5), cytokine concentrations were highest in acute CM, followed by SMA, and were only mildly elevated in UCM. Cytokine concentrations had fallen to control levels when remeasured at 1 month of convalescence in all three clinical malaria groups. Ratios of IL-10 to tumor necrosis factor alpha (TNF-α) and of IL-10 to IL-6 followed a similar pattern. Children presenting with acute CM had significantly higher concentrations of TNF-α (P < 0.001), interferon gamma (IFN-γ) (P = 0.0019), IL-2 (P = 0.0004), IL-6 (P < 0.001), IL-8 (P < 0.001), and IL-10 (P < 0.001) in sera than healthy controls. Patients with acute CM had significantly higher concentrations of IL-6 (P < 0.001) and IL-10 (P = 0.0003) than those presenting with acute SMA. Our findings are consistent with the concept that high levels of proinflammatory cytokines, despite high levels of the anti-inflammatory cytokine IL-10, could contribute to the pathogenesis of CM.

2012 ◽  
Vol 80 (9) ◽  
pp. 2997-3007 ◽  
Author(s):  
Juliana V. Harris ◽  
Tiffany M. Bohr ◽  
Catherine Stracener ◽  
Mary E. Landmesser ◽  
Vladimir Torres ◽  
...  

ABSTRACTLack of an adequate animal model ofPlasmodium falciparumsevere malarial anemia (SMA) has hampered the understanding of this highly lethal condition. We developed a model of SMA by infecting C57BL/6 mice withP. chabaudifollowed after recovery byP. bergheiinfection.P. chabaudi/P. berghei-infected mice had an initial 9- to 10-day phase of relatively low parasitemia and severe anemia, followed by a second phase of hyperparasitemia, more profound anemia, reticulocytosis, and death 14 to 21 days after infection.P. chabaudi/P. berghei-infected animals had more intense splenic hematopoiesis, higher interleukin-10 (IL-10)/tumor necrosis factor alpha and IL-12/gamma interferon (IFN-γ) ratios, and higher antibody levels againstP. bergheiandP. chabaudiantigens thanP. berghei-infected orP. chabaudi-recovered animals. Early treatment with chloroquine or artesunate did not prevent the anemia, suggesting that the bulk of red cell destruction was not due to the parasite. Red cells fromP. chabaudi/P. berghei-infected animals had increased surface IgG and C3 by flow cytometry. However, C3−/−mice still developed anemia. Tracking of red cells labeledex vivoandin vivoand analysis of frozen tissue sections by immunofluorescence microscopy showed that red cells fromP. chabaudi/P. berghei-infected animals were removed at an accelerated rate in the liver by erythrophagocytosis. This model is practical and reproducible, and its similarities withP. falciparumSMA in humans makes it an appealing system with which to study the pathogenesis of this condition and explore potential immunomodulatory interventions.


2006 ◽  
Vol 74 (9) ◽  
pp. 5249-5260 ◽  
Author(s):  
Christopher C. Keller ◽  
Ouma Yamo ◽  
Collins Ouma ◽  
John Michael Ong'echa ◽  
David Ounah ◽  
...  

ABSTRACT Severe malarial anemia (SMA) is a primary cause of morbidity and mortality in immune-naïve infants and young children residing in areas of holoendemic Plasmodium falciparum transmission. Although the immunopathogenesis of SMA is largely undefined, we have previously shown that systemic interleukin-12 (IL-12) production is suppressed during childhood blood-stage malaria. Since IL-10 and tumor necrosis factor alpha (TNF-α) are known to decrease IL-12 synthesis in a number of infectious diseases, altered transcriptional regulation of these inflammatory mediators was investigated as a potential mechanism for IL-12 down-regulation. Ingestion of naturally acquired malarial pigment (hemozoin [PfHz]) by monocytes promoted the overproduction of IL-10 and TNF-α relative to the production of IL-12, which correlated with an enhanced severity of malarial anemia. Experiments with cultured peripheral blood mononuclear cells (PBMC) and CD14+ cells from malaria-naïve donors revealed that physiological concentrations of PfHz suppressed IL-12 and augmented IL-10 and TNF-α by altering the transcriptional kinetics of IL-12p40, IL-10, and TNF-α, respectively. IL-10 neutralizing antibodies, but not TNF-α antibodies, restored PfHz-induced suppression of IL-12. Blockade of IL-10 and the addition of recombinant IL-10 to cultured PBMC from children with SMA confirmed that IL-10 was responsible for malaria-induced suppression of IL-12. Taken together, these results demonstrate that PfHz-induced up-regulation of IL-10 is responsible for the suppression of IL-12 during malaria.


2011 ◽  
Vol 79 (8) ◽  
pp. 3149-3158 ◽  
Author(s):  
Wasimul Bari ◽  
Yoon-Jae Song ◽  
Sang Sun Yoon

ABSTRACTVibrio choleraeO1 has two biotypes, El Tor and Classical, and the latter is now presumed to be extinct in nature. Under carbohydrate-rich growth conditions, El Tor biotype strains produce the neutral fermentation end product 2,3-butanediol (2,3-BD), which prevents accumulation of organic acids from mixed acid fermentation and thus avoids a lethal decrease in the medium pH, while the Classical biotype strains fail to do the same. In this study, we investigated the inhibitory effect of 2,3-BD on the production of two proinflammatory biomarkers, intreleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-α), in human intestinal epithelial HT29 and alveolar epithelial A549 cells. Cell-free culture supernatants of El Tor strain N16961 grown in LB supplemented with 1% glucose induced a negligible amount of IL-8 or TNF-α, while the Classical O395 strain induced much higher levels of these proinflammatory cytokines. On the other hand, three mutant strains constructed from the N16961 strain with defects in the constitutive 2,3-BD pathway were also able to induce high levels of cytokines. When HT29 and A549 cells were treated with bacterial flagella, known proinflammatory cytokine inducers, and chemically synthesized 2,3-BD at various concentrations, a dose-dependent decrease in IL-8 and TNF-α production was observed, demonstrating the suppressive effect of 2,3-BD on the production of proinflammatory cytokines in epithelial cells. Upon cotreatment with extraneous 2,3-BD, elevated levels of IκBα, the inhibitor of the NF-κB pathway, were detected in both HT29 and A549 cells. Furthermore, treatments containing 2,3-BD elicited lower levels of NF-κB-responsive luciferase activity, demonstrating that the reduced cytokine production is likely through the inhibition of the NF-κB pathway. These results reveal a novel and potential role of 2,3-BD as an immune modulator that might have conferred a superior pathogenic potential of the El Tor over the Classical biotype.


2015 ◽  
Vol 23 (2) ◽  
pp. 95-103 ◽  
Author(s):  
Wilson L. Mandala ◽  
Chisomo L. Msefula ◽  
Esther N. Gondwe ◽  
James J. Gilchrist ◽  
Stephen M. Graham ◽  
...  

ABSTRACTLymphocytes are implicated in immunity and pathogenesis of severe malaria. Since lymphocyte subsets vary with age, assessment of their contribution to different etiologies can be difficult. We immunophenotyped peripheral blood from Malawian children presenting with cerebral malaria, severe malarial anemia, and uncomplicated malaria (n= 113) and healthy aparasitemic children (n= 42) in Blantyre, Malawi, and investigated lymphocyte subset counts, activation, and memory status. Children with cerebral malaria were older than those with severe malarial anemia. We found panlymphopenia in children presenting with cerebral malaria (median lymphocyte count, 2,100/μl) and uncomplicated malaria (3,700/μl), which was corrected in convalescence and was absent in severe malarial anemia (5,950/μl). Median percentages of activated CD69+NK (73%) and γδ T (60%) cells were higher in cerebral malaria than in other malaria types. Median ratios of memory to naive CD4+lymphocytes were higher in cerebral malaria than in uncomplicated malaria and low in severe malarial anemia. The polarized lymphocyte subset profiles of different forms of severe malaria are independent of age. In conclusion, among Malawian children cerebral malaria is characterized by lymphocyte activation and increased memory cells, consistent with immune priming. In contrast, there are reduced memory cells and less activation in severe malaria anemia. Further studies are required to understand whether these immunological profiles indicate predisposition of some children to one or another form of severe malaria.


2011 ◽  
Vol 80 (3) ◽  
pp. 1121-1127 ◽  
Author(s):  
Yoshifumi Kimizuka ◽  
Soichiro Kimura ◽  
Tomoo Saga ◽  
Makoto Ishii ◽  
Naoki Hasegawa ◽  
...  

Interleukin-17 (IL-17) is a key factor in T helper type 17 (Th17) lineage host responses and plays critical roles in immunological control of a variety of infectious diseases. AlthoughLegionella pneumophila, an intracellular bacterium found widely in the environment, often causes a serious and life-threatening pneumonia in humans, the contribution of IL-17 to immune function duringLegionellapneumonia is unknown. In the present study, we used an experimentalLegionellapneumonia infection to clarify the role of IL-17 in the resulting immune response. We observed robust production of pulmonary IL-17A and IL-17F (IL-17A/F), peaking on day 1 and declining thereafter. Upregulated production of tumor necrosis factor alpha (TNF-α), IL-6, and IL-1β, but not monocyte chemotactic protein 1 (MCP-1), was observed inLegionella-infected bone marrow-derived macrophages from BALB/c mice that had been stimulated with IL-17A or IL-17F. A significant decrease in the production of proinflammatory cytokines IL-6 and TNF-α was observed in IL-17A/F-deficient mice (BALB/c background) infected withL. pneumophila. Moreover, we found impaired neutrophil migration and lower numbers of chemokines (KC, LIX, and MIP-2) in IL-17A/F-deficient mice. IL-17A/F-deficient mice also eliminatedL. pneumophilamore slowly and were less likely to survive a lethal challenge. These results demonstrate that IL-17A/F plays a critical role inL. pneumophilapneumonia, probably through induction of proinflammatory cytokines and accumulation of neutrophils at the infection site.


2004 ◽  
Vol 72 (10) ◽  
pp. 5630-5637 ◽  
Author(s):  
K. E. Lyke ◽  
R. Burges ◽  
Y. Cissoko ◽  
L. Sangare ◽  
M. Dao ◽  
...  

ABSTRACT Inflammatory cytokines play an important role in human immune responses to malarial disease. However, the role of these mediators in disease pathogenesis, and the relationship between host protection and injury remains unclear. A total of 248 cases of severe Plasmodium falciparum malaria among children aged 3 months to 14 years residing in Bandiagara, Mali, were matched to cases of uncomplicated malaria and healthy controls. Using modified World Health Organization criteria for defining severe malaria, we identified 100 cases of cerebral malaria (coma, seizure, and obtundation), 17 cases of severe anemia (hemoglobin, <5 g/dl), 18 cases combined cerebral malaria with severe anemia, and 92 cases with hyperparasitemia (asexual trophozoites, >500,000/mm3). Significantly elevated levels (given as geometric mean concentrations in picograms/milliliter) of interleukin-6 (IL-6; 485.2 versus 54.1; P = <0.001), IL-10 (1,099.3 versus 14.1; P = <0.001), tumor necrosis factor alpha (10.1 versus 7.7; P = <0.001), and IL-12(p70) (48.9 versus 31.3; P = 0.004) in serum were found in severe cases versus healthy controls. Significantly elevated levels of IL-6 (485.2 versus 141.0; P = <0.001) and IL-10 (1,099.3 versus 133.9; P = <0.001) were seen in severe malaria cases versus uncomplicated malaria controls. Cerebral malaria was associated with significantly elevated levels of IL-6 (754.5 versus 311.4; P = <0.001) and IL-10 (1,405.6 versus 868.6; P = 0.006) compared to severe malaria cases without cerebral manifestations. Conversely, lower levels of IL-6 (199.2 versus 487.6; P = 0.03) and IL-10 (391.1 versus 1,160.9; P = 0.002) were noted in children with severe anemia compared to severe malaria cases with hemoglobin at >5 g/dl. Hyperparasitemia was associated with significantly lower levels of IL-6 (336.6 versus 602.1; P = 0.002). These results illustrate the complex relationships between inflammatory cytokines and disease in P. falciparum malaria.


Author(s):  
Tongtong Zhao ◽  
Kai Zhang ◽  
Yelei Zhang ◽  
Yating Yang ◽  
Xiaoshuai Ning ◽  
...  

Abstract Rationale and objective Clozapine (CLZ) is the most effective drug for treatment-resistant schizophrenia but is associated with many side effects, including glycometabolism disorders. Immunological mechanisms may be involved in the development of clozapine side effects. Research relating the immunomodulatory effects of clozapine and its early markers to clinically relevant adverse events is needed to reduce the harmful side effects of clozapine. This study aimed to investigate the role of proinflammatory cytokines in clozapine-associated glycometabolism disorders. Methods We measured the effect of a range of doses of clozapine on glycometabolism-related parameters and proinflammatory cytokines levels in mice peripheral blood. We also examined the differences between these indicators in the peripheral blood of clozapine-treated schizophrenia patients and healthy controls. Furthermore, we detected proinflammatory cytokines expression in mice pancreatic tissue. Results Following clozapine administration, glucagon significantly decreased in mouse serum, and proinflammatory cytokine IL-β levels markedly increased. Clozapine reliably increased proinflammatory cytokines (IL-1β, IL-6, and TNF-α) expression in murine pancreatic tissue. Compared with healthy controls, clozapine-treated patients’ BMI, blood glucose, and proinflammatory cytokines (IL-1β, IL-6, and TNF-α) increased significantly. In clozapine-treated patients, a higher clozapine daily dosage was associated with higher levels of the proinflammatory cytokines IL-1β and IL-6, and a significant positive correlation was observed between blood glucose levels and the proinflammatory cytokines IL-6 and TNF-α. Conclusion Findings from animal experiments and clinical trials have shown clear evidence that clozapine has a regulatory effect on immune-related proinflammatory cytokines and influences glycometabolism indicators.


2014 ◽  
Vol 82 (9) ◽  
pp. 3775-3782 ◽  
Author(s):  
Lyticia A. Ochola ◽  
Cyrus Ayieko ◽  
Lily Kisia ◽  
Ng'wena G. Magak ◽  
Estela Shabani ◽  
...  

ABSTRACTIndividuals naturally exposed toPlasmodium falciparumlose clinical immunity after a prolonged lack of exposure.P. falciparumantigen-specific cytokine responses have been associated with protection from clinical malaria, but the longevity ofP. falciparumantigen-specific cytokine responses in the absence of exposure is not well characterized. A highland area of Kenya with low and unstable malaria transmission provided an opportunity to study this question. The levels of antigen-specific cytokines and chemokines associated in previous studies with protection from clinical malaria (gamma interferon [IFN-γ], interleukin-10 [IL-10], and tumor necrosis factor alpha [TNF-α]), with increased risk of clinical malaria (IL-6), or with pathogenesis of severe disease in malaria (IL-5 and RANTES) were assessed by cytometric bead assay in April 2008, October 2008, and April 2009 in 100 children and adults. During the 1-year study period, none had an episode of clinicalP. falciparummalaria. Two patterns of cytokine responses emerged, with some variation by antigen: a decrease at 6 months (IFN-γ and IL-5) or at both 6 and 12 months (IL-10 and TNF-α) or no change over time (IL-6 and RANTES). These findings document thatP. falciparumantigen-specific cytokine responses associated in prior studies with protection from malaria (IFN-γ, TNF-α, and IL-10) decrease significantly in the absence ofP. falciparumexposure, whereas those associated with increased risk of malaria (IL-6) do not. The study findings provide a strong rationale for future studies of antigen-specific IFN-γ, TNF-α, and IL-10 responses as biomarkers of increased population-level susceptibility to malaria after prolonged lack ofP. falciparumexposure.


2011 ◽  
Vol 79 (7) ◽  
pp. 2597-2607 ◽  
Author(s):  
Poonam Dharmani ◽  
Jaclyn Strauss ◽  
Christian Ambrose ◽  
Emma Allen-Vercoe ◽  
Kris Chadee

ABSTRACTThe etiology of inflammatory bowel disease is not completely known, but it is influenced by the presence of normal gut microflora as well as yet-unrecognized pathogens. The anaerobic, Gram-negative bacterial speciesFusobacterium nucleatumis a common resident of the human mouth and gut and varies in its pathogenic potential. In this study, we demonstrate that highly invasiveF. nucleatumisolates derived from the inflamed guts of Crohn's disease patients evoked significantly greater MUC2 and tumor necrosis factor alpha (TNF-α) gene expression than minimally invasive strains isolated from the noninflamed gut in human colonic epithelial cells and in a rat ligated colonic loop model of infection. Only liveF. nucleatuminduced mucin secretion and TNF-α expression in direct contact with and/or during invasion of colonic cells. In rat colons, mucin secretion was augmented in response to a highly invasiveF. nucleatumisolate but was unaffected by treatment with a minimally invasive strain. Taken together, these studies reveal thatF. nucleatummay represent a challenging pathogen in the etiology of gut inflammatory diseases and highlight the importance of different pathotypes of candidate bacterial species in disease pathogenesis.


2018 ◽  
Vol 86 (5) ◽  
Author(s):  
Wayne Nishio Ayre ◽  
Genevieve Melling ◽  
Camille Cuveillier ◽  
Madhan Natarajan ◽  
Jessica L. Roberts ◽  
...  

ABSTRACTThis study investigated the host response to a polymicrobial pulpal infection consisting ofStreptococcus anginosusandEnterococcus faecalis, bacteria commonly implicated in dental abscesses and endodontic failure, using a validatedex vivorat tooth model. Tooth slices were inoculated with planktonic cultures ofS. anginosusorE. faecalisalone or in coculture atS. anginosus/E. faecalisratios of 50:50 and 90:10. Attachment was semiquantified by measuring the area covered by fluorescently labeled bacteria. Host response was established by viable histological cell counts, and inflammatory response was measured using reverse transcription-quantitative PCR (RT-qPCR) and immunohistochemistry. A significant reduction in cell viability was observed for single and polymicrobial infections, with no significant differences between infection types (∼2,000 cells/mm2for infected pulps compared to ∼4,000 cells/mm2for uninfected pulps).E. faecalisdemonstrated significantly higher levels of attachment (6.5%) thanS. anginosusalone (2.3%) and mixed-species infections (3.4% for 50:50 and 2.3% for 90:10), with a remarkable affinity for the pulpal vasculature. Infections withE. faecalisdemonstrated the greatest increase in tumor necrosis factor alpha (TNF-α) (47.1-fold forE. faecalis, 14.6-fold forS. anginosus, 60.1-fold for 50:50, and 25.0-fold for 90:10) and interleukin 1β (IL-1β) expression (54.8-fold forE. faecalis, 8.8-fold forS. anginosus, 54.5-fold for 50:50, and 39.9-fold for 90:10) compared to uninfected samples. Immunohistochemistry confirmed this, with the majority of inflammation localized to the pulpal vasculature and odontoblast regions. Interestingly,E. faecalissupernatant and heat-killedE. faecalistreatments were unable to induce the same inflammatory response, suggestingE. faecalispathogenicity in pulpitis is linked to its greater ability to attach to the pulpal vasculature.


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