Relationship between specific serum IgE to Ascaris lumbricoides and onset of respiratory symptoms in Bangladesh immigrants

Helminth infections and allergic diseases: systematic review and meta-analysis of the global literature

INTRODUCTION

There is considerable research interest in the role of helminth infections in the development of allergic diseases. However, findings from previous studies are mixed. Existing systematic reviews of these studies are outdated. We performed a systematic review of the global literature on the association between helminth infections and development and clinical outcomes of allergic diseases.

METHODS

We searched Cochrane Library, MEDLINE, EMBASE, ISI Web of Science, PubMed, Global Index Medicus, Scielo, KoreaMed, Google Scholar, and Lilacs for studies published up to January 2020. We included observational epidemiological studies (cohort, case-control and cross-sectional studies) of children and adults reporting associations between helminth infections and asthma, allergic rhinitis, eczema and atopy. We performed random-effects meta-analysis to summarize the effect estimates.

RESULTS

We included 80 studies with 99,967 participants. In the meta-analyses, we did not observe an overall association between helminth infections and allergic diseases. There was, however, evidence that A. lumbricoides infections was associated with an increased risk of bronchial hyperreactivity in children (RR:1.41, 95%CI: 1.17-1.70; I²=50, p for I²=0.09), and was associated with an increased risk of atopy among helminth-infected adults (RR:1.37, 95%CI: 1.18-1.61; I²=52, p for I²=0.02). We found no study that addressed the association between helminth infection and clinical outcomes of allergic diseases. The overall strength of the underlying evidence was low to moderate.

CONCLUSION

Helminth infections may increase the risk of bronchial hyperreactivity in children and atopy in adults. Well-designed longitudinal cohorts may help clarify potential causal associations between chronic helminth infections and allergic diseases.

Is Ascaris lumbricoides a risk factor for development of asthma? A systematic review and meta-analysis

There are numerous epidemiological and experimental evidences to suggest that Ascaris lumbricoides infection is a neglected risk factor for development of asthma. For this purpose, we conducted a systematic review and meta-analysis for better understanding of this relationship. Systematic searching (PubMed, Scopus, Web of Science and Google Scholar) was done, up to September 30, 2019 to identify the relevant studies. We applied random-effects meta-analysis model to generate the overall odds ratio (OR) and 95% confidence intervals (CIs). Heterogeneity was assessed with I2 and τ2 statistic. Finally, 19 studies (totally 25 datasets), including 14 datasets with microscopic methods (1830 asthmatic patients (APs) and 3802 healthy controls (HCs)) and 11 datasets with serological methods (1543 APs and 3507 HCs) met the eligibility criteria. Considering to the serological methods, our results demonstrated that the APs had higher seroprevalence rate of A. lumbricoides (48.3% vs. 35.1%) than HCs, showing a significant association (pooled crude OR, 1.53; 95%CI, 1.07-2.18). Moreover, microscopic methods showed a higher prevalence of A. lumbricoides infection in the APs compared to the HCs (37.2% vs. 30.2%), but no significant association was found between APs and HCs (pooled crude OR, 1.19; 95%CI, 0.92-1.55). After adjustment for confounders, results showed no significant association for both serological (pooled adjusted OR, 1.43; 95%CI, 0.93-2.19) and microscopic (pooled adjusted OR, 1.05; 95%CI, 0.78-1.42) methods. Despite heterogeneous results, accurate and better quality studies are needed to determine the effect of A. lumbricoides infection on induction or exacerbation of asthma.

Ascaris Larval Infection and Lung Invasion Directly Induce Severe Allergic Airway Disease in Mice

Ascaris lumbricoides (roundworm) is the most common helminth infection globally and a cause of lifelong morbidity that may include allergic airway disease, an asthma phenotype. We hypothesize that Ascaris larval migration through the lungs leads to persistent airway hyperresponsiveness (AHR) and type 2 inflammatory lung pathology despite resolution of infection that resembles allergic airway disease. Mice were infected with Ascaris by oral gavage. Lung AHR was measured by plethysmography and histopathology with hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) stains, and cytokine concentrations were measured by using Luminex Magpix. Ascaris-infected mice were compared to controls or mice with allergic airway disease induced by ovalbumin (OVA) sensitization and challenge (OVA/OVA). Ascaris-infected mice developed profound AHR starting at day 8 postinfection (p.i.), peaking at day 12 p.i. and persisting through day 21 p.i., despite resolution of infection, which was significantly increased compared to controls and OVA/OVA mice. Ascaris-infected mice had a robust type 2 cytokine response in both the bronchoalveolar lavage (BAL) fluid and lung tissue, similar to that of the OVA/OVA mice, including interleukin-4 (IL-4) (P < 0.01 and P < 0.01, respectively), IL-5 (P < 0.001 and P < 0.001), and IL-13 (P < 0.001 and P < 0.01), compared to controls. By histopathology, Ascaris-infected mice demonstrated early airway remodeling similar to, but more profound than, that in OVA/OVA mice. We found that Ascaris larval migration causes significant pulmonary damage, including AHR and type 2 inflammatory lung pathology that resembles an extreme form of allergic airway disease. Our findings indicate that ascariasis may be an important cause of allergic airway disease in regions of endemicity.

Involvement of NK Cells against Tumors and Parasites

Host resistance against pathogens depends on a complex interplay of innate and adaptive immune mechanisms. Acting as an early line of defence, the immune system includes activation of neutrophils, tissue macrophages, monocytes, dendritic cells, eosinophils and natural killer (NK) cells. NK cells are lymphoid cells that can be activated without previous stimulation and are therefore like macrophages in the first line of defence against tumor cells and a diverse range of pathogens. NK cells mediate significant activity and produce high levels of proinflammatory cytokines in response to infection. Their cytotoxicity production is induced principally by monocyte-, macrophage- and dendritic cell-derived cytokines, but their activation is also believed to be cytokine-mediated. Recognition of infection by NK cells is accomplished by numerous activating and inhibitory receptors on the NK cells’ surface that selectively trigger the cytolytic activity in a major histocompability complex-independent manner. NK cells have trypanocidal activity of fibroblast cells and mediate direct destruction of extracellular epimastigote and trypomastigote forms of T. cruzi and T. lewisi in vitro; moreover, they kill plasmodia-infected erythrocytes directly through cell-cell interaction. This review provides a more detailed analysis of how NK cells recognize and respond to parasites and how they mediate cytotoxicity against tumor cells. Also the unique role of NK cells in innate immunity to infection and the relationship between parasites and carcinogenesis are discussed.

Differences and similarities between allergic and nonallergic rhinitis in a large sample of adult patients with rhinitis symptoms

BACKGROUND

Allergic rhinitis (AR) and nonallergic rhinitis (NAR) may present with different clinical and laboratory characteristics.

METHODS

A total of 1,511 consecutive patients, aged 18-81 years, diagnosed with rhinitis, 56% females and 44% males, underwent complete allergic evaluation including skin prick test, blood eosinophil counts, nasal eosinophil counts, peak nasal inspiratory flow (PNIF) measurement and evaluation of nasal symptoms using a visual analog scale (VAS).

RESULTS

A total of 1,107 patients (73%)had AR, whereas 404 (27%) had NAR. Patients with NAR were older and predominantly female. A higher nasal eosinophils count was associated with AR and a lack of clinical response to antihistamines. AR patients had more sneezing and nasal pruritus, whereas NAR was characterized mainly by nasal obstruction and rhinorrhea. AR patients had more severe symptoms and recurrent conjunctivitis, whereas NAR patients had slightly more frequent episodes of recurring headaches as well as olfactory dysfunction. PNIF, blood eosinophil counts and VAS of nasal symptoms were higher in patients with AR. In a final logistic regression model, 10 variables were statistically different between AR and NAR: age [OR 0.97 (95% CI 0.96-0.98)], sneezing [OR 4.09 (95% CI 2.78-6.00)], nasal pruritus [OR 3.84 (95% CI 2.60-5.67)], mild symptoms [OR 0.21 (95% CI 0.09-0.49)], intermittent/severe nasal symptoms [OR 3.66 (95% CI 2.06-6.50)], VAS [OR 1.06 (95% CI 1.04-1.08)], clinical response to antihistamines [OR 22.59 (95% CI 13.79-37.00)], conjunctivitis [OR 4.49 (95% CI 2.86-7.05)], PNIF [OR 1.01 (95% CI 1.00-1.01)] and nasal eosinophil counts [OR 1.14 (95% CI 1.10-1.18)]. Receiver operating characteristic analysis showed high predictive accuracy for a model including these variables independently of the diagnosis of AR/NAR (cutoff <0.74).

CONCLUSIONS

We showed that the several clinical and laboratory parameters reported above may help to reinforce or exclude the diagnosis of AR obtained with skin prick test.

Clinical Importance of Eosinophil Count in Nasal Fluid in Patients with Allergic and Non-Allergic Rhinitis

Eosinophil count in nasal fluid (ECNF) was used to differentiate nasal pathologies. Receiver Operating Characteristic (ROC) curve analysis and the area under the curve (AUC) were performed to evaluate the ECNF's accuracy in distinguishing allergic rhinitis (AR) from non-allergic rhinitis (NAR). We also evaluated the accuracy of ECNF in recognizing patients with mild and severe symptoms of rhinitis and patients with ineffective and effective clinical responses to antihistamines. 1,170 consecutive adult patients with a clinical history of rhinitis were studied. ECNF's median in AR was 6.0 and 2.0 in NAR and the best cut-off value was > 3.0, AUC = 0.75. ECNF's median in AR with mild nasal symptoms was 3.0 and 7.0 with severe symptoms, and the best cut-off value was 4.0, AUC = 0.90. ECNF's median in NAR with mild nasal symptoms was 2.0 and 8.5 with severe symptoms, and the best cut-off value was > 4.0, AUC = 0.86. ECNF's median in AR with effective clinical response to antihistamines was 4.0 and 8.0 with ineffective response, the best cut-off value was ≤ 5.0, AUC = 0.94. ECNF's median in NAR with an effective clinical response to antihistamines was 1.0 and 2.0 with ineffective response, and the best cut-off value was ≤ 3.0, AUC = 0.64. Our results suggest an interesting practical use of ECNF data as evaluator of the clinical severity both AR and NAR. As predictor of the clinical response to antihistamines, ECNF is accurate only in patients with AR. The ECNF's performance was moderately accurate in distinguish patients with AR and NAR.

Expression of Co-stimulatory molecules on langerhans cells in lesional epidermis of human atopic dermatitis

Langerhans cells (LC) are immature dendritic cells (DC) present in the skin epithelium. To understand the molecular and cellular mechanisms governing the inflammatory reaction in atopic dermatitis (AD), the expression of the LC specific marker CD1a, a member of major histocompatibility (MHC)-like glycoproteins, and the co-stimulatory molecules CD80 and CD86, expressed on functionally mature dendritic cells, were counted in lesional biopsies and normal epidermis by an immunohistochemical method. CD1a specific staining was observed in both normal and AD lesion specimens. CD80 and CD86 positive cells with morphological characteristics of the LC were found in lesional AD epidermis, suggesting a high level of functional maturity of these cells and their involvement in chronic inflammatory disease.

Improvement of cytotoxic effects induced by mitoxantrone on hormone-refractory metastatic prostate cancer cells by co-targeting epidermal growth factor receptor and hedgehog signaling cascades

The results of the present study revealed for the first time the possibility to use a combination of mitoxantrone with gefitinib and cyclopamine for inhibiting the growth of epidermal growth factor (EGF), sonic hedgehog- (SHHNp), and serum-stimulated androgen-sensitive LNCaP-C33 and androgen-independent (AI) LNCaP-C81, DU145 and PC3 prostate cancer (PC) cells. The supra-additive anti-proliferative effects of drugs were mediated via a blockade of the PC3 cells in the G(1) and G(2)M phases of the cell cycle. Importantly, the combination of mitoxantrone plus gefitinib and/or cyclopamine also caused a higher rate of apoptotic death of PC cells including enriched fraction of CD44(high) PC3 cell subpopulation as compared to the individual agents or bi-combination of drugs. The cytotoxic effects induced by mitoxantrone, gefitinib and cyclopamine on PC3 cells appear to be at least partly mediated through the depolarization of the mitochondrial membrane, release of cytochrome c into the cytosol, hydrogen peroxide production and activation of caspase cascades. These findings indicate that the simultaneous blockade of EGF-EGFR and sonic hedgehog tumorigenic signaling cascades may represent a promising strategy for improving the efficacy of current mitoxantrone-based therapies against incurable AI and metastatic PCs in the clinics.

Similarity and differences in elderly patients with fixed airflow obstruction by asthma and by chronic obstructive pulmonary disease

BACKGROUND

Epidemiologic studies have demonstrated that elderly patients with fixed airflow obstruction can be affected by asthma or chronic obstructive pulmonary disease (COPD).

METHODS

We studied 49 consecutive elderly outpatients, presenting fixed airflow obstruction, by clinical history (smoking), pulmonary function tests, blood gas analysis, and induced sputum.

RESULTS

The age was not different in patients with COPD (n=28) and asthma (n=21) (70.2+/-3.9 years vs. 69.6+/-3.7 years), also the degree of fixed airflow obstruction was similar (FEV1: 58.3+/-1.5% vs. 59.0+/-1.4% of predicted). Patients with asthma had significantly more eosinophils in peripheral blood (0.43+/-0.05x10(-3)microL vs. 0.27+/-0.1x10(-3)microL, P<0.0001), and in induced sputum (5.0% [(p25th and p75th) 5.0-6.0%] vs. 1.0% [(p25th and p75th) 0.01-1.0%]; P<0.0001), as well as serum ECP (18.6+/-4.9ng/mL vs. 7.7+/-4.7ng/mL, P<0.0001) and ECP in the induced sputum (31.6+/-2.9ng/mL vs. 5.6+/-4.9ng/mL, P<0.0001). Finally, in induced sputum the eosinophils EG2+ were higher in patients with asthma than in patients with COPD (40.5 [(p25th and p75th) 39.3-44.3] MFI vs. 3.9 [(p25th and p75th) 0-11.4] MFI, P<0.0001). They also had significantly higher diffusing capacity, and a greater reversibility to steroids, after 14-day course of therapy, whereas the reversibility to 400microg of salbutamol was similar.

CONCLUSION

Despite similar fixed airflow obstruction, elderly patients with asthma have distinct characteristics compared with patients with COPD.