Dietary lycopene supplementation suppresses Th2 responses and lung eosinophilia in a mouse model of allergic asthma

Allergic airways disease (AAD) is associated with an increased influx of eosinophils to the lungs, mucus hypersecretion and Th2 cytokine production. Dietary antioxidant supplementation may alter cytokine responses and thus allergic inflammation. Lycopene is a potent dietary antioxidant. The objective of this study was to investigate the effects of lycopene, on allergic inflammation, in a mouse model of AAD. BALB/c mice receiving lycopene supplement or control were intraperitoneally sensitised and intranasally challenged with ovalbumin (OVA) to induce AAD. The effect of supplementation on inflammatory cell influx into bronchoalveolar lavage fluid, lung tissue and blood, mucus-secreting cell numbers in the airways, draining lymph node OVA-specific cytokine release, serum IgG1 levels and lung function in AAD was assessed. Supplementation reduced eosinophilic infiltrates in the bronchoalveolar lavage fluid, lung tissue and blood, and mucus-secreting cell numbers in the airways. The OVA-specific release of Th2-associated cytokines IL-4 and IL-5 was also reduced. We conclude that supplementation with lycopene reduces allergic inflammation both in the lungs and systemically, by decreasing Th2 cytokine responses. Thus, lycopene supplementation may have a protective effect against asthma.     

Immunodetection of occult eosinophils in lung tissue biopsies may help predict survival in acute lung injury

Background

Acute lung injury (ALI) is a serious respiratory disorder for which therapy is primarily supportive once infection is excluded. Surgical lung biopsy may rule out other diagnoses, but has not been generally useful for therapy decisions or prognosis in this setting. Importantly, tissue and peripheral blood eosinophilia, the hallmarks of steroid-responsive acute eosinophilic pneumonia, are not commonly linked with ALI. We hypothesized that occult eosinophilic pneumonia may explain better outcomes for some patients with ALI.

Methods

Immunohistochemistry using a novel monoclonal antibody recognizing eosinophil peroxidase (EPX-mAb) was used to assess intrapulmonary eosinophil accumulation/degranulation. Lung biopsies from ALI patients (n = 20) were identified following review of a pathology database; 45% of which (i.e., 9/20) displayed classical diffuse alveolar damage (ALI-DAD). Controls were obtained from uninvolved tissue in patients undergoing lobectomy for lung cancer (n = 10). Serial biopsy sections were stained with hematoxylin and eosin (H&E) and subjected to EPX-mAb immunohistochemistry.

Results

EPX-mAb immunohistochemistry provided a >40-fold increased sensitivity to detect eosinophils in the lung relative to H&E stained sections. This increased sensitivity led to the identification of higher numbers of eosinophils in ALI patients compared with controls; differences using H&E staining alone were not significant. Clinical assessments showed that lung infiltrating eosinophil numbers were higher in ALI patients that survived hospitalization compared with non-survivors. A similar conclusion was reached quantifying eosinophil degranulation in each biopsy.

Conclusion

The enhanced sensitivity of EPX-mAb immunohistochemistry uniquely identified eosinophil accumulation/degranulation in patients with ALI relative to controls. More importantly, this method was a prognostic indicator of patient survival. These observations suggest that EPX-mAb immunohistochemistry may represent a diagnostic biomarker identifying a subset of ALI patients with improved clinical outcomes.     

The 434(G>C) polymorphism within the coding sequence of Eosinophil Cationic Protein (ECP) correlates with the natural course of Schistosoma mansoni infection

Schistosomiasis is a chronic parasitic infection with over 200 million people infected worldwide. In Schistosoma mansoni infections, parasite-derived eggs get trapped in the liver, causing the formation of granulomas, which may develop into periportal fibrosis and portal hypertension, and thus severe morbidity. Eosinophil cationic protein (ECP) is a secretory protein of eosinophil granulocytes that efficiently kills the larval stage of S. mansoni, but also affects fibroblast functions. We have investigated the prevalence of the ECP gene polymorphism 434(G>C) in two African populations, from an S. mansoni endemic area in Uganda (n=297) and from a non-endemic area in Sudan (n=78), and also compared these with a Swedish population (n=209). The genotype frequencies in the Ugandan population differed significantly from both the Sudanese and Swedish populations (P<0.001). In the Ugandan population there was a significant association between genotype and prevalence of infection (P=0.03), with lower prevalence in subjects with the GG genotype compared with GC (P=0.02) and CC (P=0.03). There was also a trend towards an association with periportal fibrosis (P=0.08) in the Ugandan population. This suggested association was confirmed when the predominant tribe (n=212) was analysed separately (P=0.004). Our results suggest that ECP may be an important protein, both in the immune response against S. mansoni and in the development of periportal fibrosis. The results also suggest genetic selection towards the ECP 434CC genotype in populations living in S. mansoni endemic areas.     

Differentiation of eosinophilic leukemia EoL-1 cells into eosinophils induced by histone deacetylase inhibitors

EoL-1 cells differentiate into eosinophils in the presence of n-butyrate, but the mechanism has remained to be elucidated. Because n-butyrate can inhibit histone deacetylases, we hypothesized that the inhibition of histone deacetylases induces the differentiation of EoL-1 cells into eosinophils. In this study, using n-butyrate and two other histone deacetylase inhibitors, apicidin and trichostatin A, we have analyzed the relationship between the inhibition of histone deacetylases and the differentiation into eosinophils in EoL-1 cells. It was demonstrated that apicidin and n-butyrate induced a continuous acetylation of histones H4 and H3, inhibited the proliferation of EoL-1 cells without attenuating the level of FIP1L1-PDGFRA mRNA, and induced the expression of markers for mature eosinophils such as integrin beta7, CCR1, and CCR3 on EoL-1 cells, while trichostatin A evoked a transient acetylation of histones and induced no differentiation into eosinophils. These findings suggest that the continuous inhibition of histone deacetylases in EoL-1 cells induces the differentiation into mature eosinophils.     

Leukotriene B4 is essential for selective eosinophil recruitment following allergen challenge of CD4+ cells in a model of chronic eosinophilic inflammation

Subcutaneous heat-coagulated egg white implants (EWI) induce chronic, intense local eosinophilia in mice, followed by asthma-like responses to airway ovalbumin challenge. Our goal was to define the mechanisms of selective eosinophil accumulation in the EWI model. EWI carriers were challenged i.p. with ovalbumin and the contributions of cellular immunity and inflammatory mediators to the resulting leukocyte accumulation were defined through cell transfer and pharmacological inhibition protocols. Eosinophil recruitment required Major Histocompatibility Complex Class II expression, and was abolished by the leukotriene B4 (LTB4) receptor antagonist CP 105.696, the 5-lipoxygenase inhibitor BWA4C and the 5-lipoxygenase activating protein inhibitor MK886. Eosinophil recruitment in EWI carriers followed transfer of: a) CD4+ (but not CD4-) cells, harvested from EWI donors and restimulated ex vivo; b) their cell-free supernatants, containing LTB4. Restimulation in the presence of MK886 was ineffective. CC chemokine receptor ligand (CCL)5 and CCL2 were induced by ovalbumin challenge in vivo. mRNA for CCL17 and CCL11 was induced in ovalbumin-restimulated CD4+ cells ex vivo. MK886 blocked induction of CCL17. Pretreatment of EWI carriers with MK886 eliminated the effectiveness of exogenously administered CCL11, CCL2 and CCL5. In conclusion, chemokine-producing, ovalbumin-restimulated CD4+ cells initiate eosinophil recruitment which is strictly dependent on LTB4 production.     

Virulizin® induces production of IL-17E to enhance antitumor activity by recruitment of eosinophils into tumors

Virulizin has demonstrated strong antitumor efficacy in a variety of human tumor xenograft models including melanoma, pancreatic cancer, breast cancer, ovarian cancer and prostate cancer. Our previous studies have demonstrated that macrophages, NK cells, and cytokines are important in the antitumor mechanism of Virulizin. Virulizin treatment of tumor bearing mice results in the expansion as well as increased activity of monocytes/macrophages and production of cytokines IL-12 and TNFalpha and activation of NK cells. In this study we show that the inflammatory cytokine IL-17E (IL-25) is induced by Virulizin treatment and is part of its antitumor mechanism. IL-17E is a proinflammatory cytokine, which induces a T(H)2 type immune response, associated with eosinophil expansion and infiltration into mucosal tissues. IL-17E was increased in sera of Virulizin-treated mice bearing human melanoma xenografts, compared to saline-treated controls, as shown by 2D gel electrophoresis and ELISA. Treatment of splenocytes in vitro with Virulizin resulted in increased IL-17E mRNA expression, which peaked between 24 and 32 h post-stimulation. Both in vitro and in vivo experiments demonstrated that B cells produced IL-17E in response to Virulizin treatment. Furthermore, Virulizin treatment in vivo resulted in increased blood eosinophilia and eosinophil infiltration into tumors. Finally, injection of recombinant IL-17E showed antitumor activity towards xenografted tumors, which correlated with increased eosinophilia in blood and tumors. Taken together, these results support another antitumor mechanism mediated by Virulizin, through induction of IL-17E by B cells, leading to recruitment of eosinophils into tumors, which may function in parallel with macrophages and NK cells in mediating tumor destruction.     

Nippostrongylus brasiliensis: phospholipase in nonsensitized and sensitized rats after challenge.

Rats given an initial infection with Nippostrongylus brasiliensis showed greatly elevated phospholipase B levels in the small intestines and lungs from 8 through 22 days after challenge. The rise in enzyme concentration occurred earlier (Days 8–11) in the proximal half of the intestine, but at Days 22, 29, and 36 the levels were much higher in the distal segments. This shift in activity correlates with the known elimination of worms and a diminishing inflammatory response in the proximal areas. The increase in enzyme activity in the intestine and lungs was associated with an increased production of eosinophils in the bone marrow 11–22 days after challenge. Rats sensitized with one stimulating infection before challenge showed an anamnestic type of response, as measured by enzyme levels in the small intestines and lungs and by the numbers of eosinophils in the bone marrow. The results are discussed in light of our similar data reported earlier from animals infected with Trichinella spiralis.     

血清嗜酸性粒细胞表达水平与鼻腔鼻窦内翻性乳头状瘤病理的相关性分析

摘要 目的：探讨血清嗜酸性粒细胞（EOS）表达水平与鼻腔鼻窦内翻性乳头状瘤（SNIP）病理的相关性。方法：选取我院2016年1月至2020年1月收治的63例SNIP患者作为研究对象,依照所有患者EOS水平将其分为低EOS组、中EOS组、高EOS组,对比三组患者的临床病理特征,并分析EOS表达水平与SNIP病理的相关性。行手术治疗后将63例患者分为预后不良组与预后良好组,对比两组患者的临床相关指标,并分析EOS表达水平对SNIP的预后预测价值。结果：三组患者临床分期、病理诊断对比差异显著（P＜0.05）;以EOS表达水平进行分级：高水平：＞300个/μL,中水平：100-300个/μL,低水平：＜100个/μL。Spearman相关分析结果显示：性别、年龄、病灶位置与EOS表达水平无明显相关性（P＞0.05）,临床分期、病理诊断与EOS水平呈负相关（P＜0.05）;预后良好组与预后不良组患者PLT水平对比无明显差异（P＞0.05）,预后两组患者L、EOS水平明显高于预后不良组,N、PLR、NLR低于预后不良组（P＜0.05）;logistic回归分析结果表明：NLR、EOS为SNIP的预后独立预测因素（P＜0.05）。结论：SNIP患者的临床分期、病理诊断与EOS表达水平呈负相关,且应用NLR和EOS可对SNIP术后复发情况进行预测,因此,可以考虑应用EOS表达水平对SNIP进行诊断与治疗效果判定。     

孟鲁司特钠联合左卡巴斯汀鼻喷剂治疗小儿过敏性鼻炎的疗效评价及对血清ECP、EOS及CRP水平的影响

目的:探讨孟鲁司特钠联合左卡巴斯汀鼻喷剂治疗小儿过敏性鼻炎的疗效及对血清嗜酸性粒细胞阳离子蛋白(ECP)、嗜酸性粒细胞(EOS)及C反应蛋白(CRP)水平的影响。方法:选择我院2016年7月～2018年7月收治的151例过敏性鼻炎患儿,按随机数字表法分为69例对照组和82例观察组,对照组采用左卡巴斯汀鼻喷剂治疗,观察组在对照组基础上联合孟鲁司特钠治疗,比较两组临床疗效,治疗前后症状及体征评分,生活质量评分,血清ECP、EOS及CRP、总免疫球蛋白E(TIg E)和特异性免疫球蛋白E(Sig E)水平,和不良反应发生情况。结果:观察组总有效率高于对照组,差异有统计学意义(P0.05)。治疗前,两组症状及体征评分,生活质量评分,血清ECP、EOS及CRP、总免疫球蛋白E(TIg E)和特异性免疫球蛋白E(Sig E)水平比较差异无统计学意义(P0.05);治疗后,两组以上指标均下降,观察组低于对照组,差异均有统计学意义(均P0.05)。两组均有胃肠道反应、口干、头痛发生,组间总不良反应发生率比较无统计学差异(P0.05)。结论:孟鲁司特钠联合左卡巴斯汀鼻喷剂治疗小儿过敏性鼻炎安全有效,能够降低血清ECP、EOS及CRP水平,促进患儿恢复。