The impact of age on serum allergen-specific IgE to inhaled molecular components

BACKGROUND

Respiratory allergy is characterised by an IgE-mediated reaction. The immune system functions, including IgE production, progressively decline over time, such as growing up and ageing. Molecular-based allergy diagnostic defines sensitisation profile. This study aimed to evaluate the impact of age on serum allergen-specific IgE to molecular component levels in a large sample of subjects.

METHODS

Serum IgE to: Phl p1, Bet v1, Ole e1, Cup a1, Par j2, Can f1, Der p2, and Fel d1 were assessed by ISAC method. Sera from 2788 patients, 1230 males (44.1%) and 1558 females (55.9%), median age 23 years (1st and 3rd quartiles: 9.7-49.7 years; age range: 1 month-103 years) were analysed.

RESULTS

The number of positive tests (i.e. sensitisation) tended to increase between birth and school-age till young adulthood and then decreased (p<0.0001) with the exception of Fel d 1 (p=0.14). A similar age-dependent trend was observed considering the levels of each allergen components: the levels of each allergen component, with the exception of Fel d 1, tended to increase till early adulthood and then to decrease reaching the lowest levels in the elderly.

CONCLUSIONS

Allergen-specific IgE production to inhaled molecular components trend to reduce with ageing, but with differences between allergens. This phenomenon should be adequately evaluated managing allergic patients.

Allergen-specific IgE to food molecular components and age: From early childhood to adulthood

BACKGROUND

Respiratory allergy is characterised by an IgE-mediated reaction. The immune system functions, including IgE production, progressively decline over time with growing up and ageing. Molecular-based allergy diagnostic defines sensitisation profile. This study aimed to evaluate the impact of age on serum allergen-specific IgE to molecular component levels in a large sample of subjects.

METHODS

Serum IgE to: rCor a11, rPru p3, nJug r3, rAra h8, rGly m4, rCor a8, nPen m1, nAct d8, Bos d 8, and nGal d2 were assessed by ISAC method. Sera from 2795 patients, 1234 males (44.1%) and 1561 females (55.9%), median age 23 years (1st and 3rd quartiles: 9.7-43.7 years; age range: 1 month-103 years) were analysed.

RESULTS

The number of positive tests (i.e. sensitisation) tended to increase between birth and school-age until young adulthood and then decreased. A similar age-dependent trend was observed considering the levels of each allergen components: the levels of each allergen component tended to increase until early adulthood, but Gal d 2 and Bos d 8 (rapidly diminishing), and then to decrease over time. However, the pattern is significantly dependent on each single tested food.

CONCLUSIONS

Allergen-specific IgE production to food molecular components tend to reduce with ageing, but with differences between allergens. This phenomenon should be adequately evaluated managing allergic patients.

Pre-co-seasonal Allergen Immunotherapy in Parietaria allergic patients

BACKGROUND

Even though the Parietaria pollen season may be rather long, many physicians think that Parietaria pollen is a perennial allergen present along the whole year. In fact, many doctors prefer to prescribe allergen immunotherapy (AIT) in Parietaria allergic patients, using continuous courses. On the other hand, physicians usually prescribe pre-co-seasonal AIT course for other pollen allergies.

OBJECTIVE

This study aimed at investigating whether a single pre-co-seasonal AIT course could be effective in Parietaria allergic patients.

METHODS

Globally, 59 subjects (31 males, mean age 35.9 years) were retrospectively evaluated. All were treated with SLIT as a pre-co-seasonal course: 33 with Parietaria extract and 26 with birch extract. Patients' perception of symptom severity and medication use was assessed by visual analogue scale, comparing the previous pollen season and the present.

RESULTS

The Parietaria 2012 pollen season started from the 60(th) day and ended at the 205(th) day of 2012. A single pre-co-seasonal SLIT course was able to significantly (p < 0.0001) reduce symptom severity and medication use.

CONCLUSION

This preliminary study demonstrates that Parietaria pollen season in Genoa lasted about six months and a single pre-co-seasonal SLIT Parietaria course could be sufficient to reduce symptom severity and medication use.

An autoregulation unit for enabling adaptive control of sensorized left ventricular assist device

This paper describes an integrated system for facing heart failures (HF) in an innovative way. Existing left ventricular assist devices (LVAD or VAD) are usually devoted to blood pumping without the possibility to adapt the speed to patient conditions during everyday activities. This is essentially due to the lack of sensorization, bulkiness, and the need of relying on device-specific controllers with reduced computing ability for the existing ventricular assist systems. In this work, an innovative integrated and portable device, the ARU, is presented for enhancing VADs applicability as a long-term solution to HF. The ARU is an universal device able to fulfill with the needs of sensorized VADs in terms of data storing, continuous monitoring, autoregulation and adaptation to patient condition changes during daily activities. The ARU is able to wirelessly interface wearable devices for offering additional monitoring features from remote. The ARU functionalities on bench have been tested by the interfacing with a sensorized VAD platform in order to prove the feasibility of the approach. Experiments of local and remote VAD speed changes and autoregulation algorithms have been successfully tested showing response time of 1 s.

Experimental integration of Autoregulation Unit for left ventricular assist devices in a cardiovascular hybrid simulator

In this paper, an Autoregulation Unit (ARU) for left ventricular sensorized assist devices (LVAD) has been used with a cardiovascular hybrid simulator mimicking physiological and pathological patient conditions. The functionalities of the ARU have been demonstrating for the successful receiving and visualization of system parameters, sending of commands for LVAD speed changes, and enabling of the autonomous flow control algorithm. Experiments of speed changes and autoregulation are reported, showing the feasibility of the approach for both local and remote control of a LVAD.

Serum specific IgE: a biomarker of response to allergen immunotherapy

BACKGROUND

Allergen immunotherapy (AIT) has proven to be effective. However, no biomarkers capable of predicting the clinical response to AIT have been detected. The aim of the present study was to determine a cutoff value for serum specific IgE that could be associated with effective AIT.

METHODS

We evaluated 174 allergic patients (83 males) with ages ranging between 6 and 77 years. All patients were monsensitized and received sublingual immunotherapy (SLIT) for at least 3 years with a single allergen extract. Symptom severity was assessed using the visual analog scale (VAS). Drug use was also evaluated. A responder was defined as a patient whose VAS score fell by at least 30% over baseline.

RESULTS

The response to SLIT was considered effective in 145 patients (83.3%). The use of allergen-specific IgE levels > 9.74 kU(A)/L as a biomarker of effective SLIT yielded a sensitivity value of 96.4%, specificity of 100%, and an area under the receiver operator characteristic curve of 0.987.

CONCLUSIONS

Assessment of serum specific-IgE before AIT could be a useful biomarker for predicting response to AIT.

TNF-alpha, IL-4R-alpha and IL-4 polymorphisms in mild to severe asthma from Italian Caucasians

Asthma is a chronic airway inflammatory disease associated with airway hyperresponsiveness which affects subjects with genetic predisposition. An association has been reported between some polymorphisms in various cytokine genes and asthma. Most of them are single nucleotide polymorphisms (SNPs). These polymorphisms are detected in the protein coding sequence or in the promoter region thus influencing cytokine production. We investigated the involvement of SNP mapping in 5 cytokine genes in mild to severe asthmatics of Italian Caucasians. The frequency of alleles and genotypes, relatively to 10 allelic specificities of the cytokine genes, was defined in 57 asthmatics and in 124 control subjects by a Polymerase Chain Reaction-Sequence Specific Primer method. TNF-alpha -308A and TNF-alpha -238A allele frequencies were higher in asthmatics than in controls (p less than 0.001). Significant differences in the frequency of IL-4 -590T allele and of IL-4Ralpha +1902A allele were also detected in asthmatics in comparison with controls (pless than 0.001 and p=0.005, respectively). Similarly, IL-1alpha -889C allele was present in 84.1 percent of asthmatics and in 70.2 percent of controls (p=0.013). Furthermore, the IL-4Ralpha +1902A/A and IL-1alpha -889C/C homozygous conditions and the TNF-alpha -308G/A, TNF-alpha -238G/A, IL-4 -590T/C and IL-10 -1082G/A heterozygous conditions were significantly associated with asthma (p less than 0.05). ACA haplotype of IL-10 was observed only in asthmatic patients. This study reports, for the first time, the frequency of 10 different single nucleotide polymorphisms in 5 cytokine genes in the Italian Caucasians. Furthermore, we also indicate that in our population some single nucleotide polymorphisms are associated with mild to severe bronchial asthma.

Blood eosinophil counts rarely reflect airway eosinophilia in children with severe asthma

BACKGROUND

The inflammatory phenotypes of severe asthma in adults may be reflected in peripheral blood. If this were true in children with severe therapy-resistant asthma (STRA), invasive tests could be avoided. At the moment there is no conclusive evidence in children.

METHODS

All patients underwent blood tests, exhaled nitric oxide (FeNO), sputum induction, bronchoalveolar lavage (BAL) and endobronchial biopsy (EB).

RESULTS

Sixty-three (71.6%) patients had a normal blood profile and only 1/88 had a combined blood eosinophilia and neutrophilia. 76/88 (86%) had normal blood eosinophils, but of these, 84% had airway eosinophilia in either BAL (n = 43;66%) or EB (n = 41;79%). In children with STRA blood eosinophilia was associated with airway eosinophilia. However, normal blood eosinophil levels did not exclude airway eosinophilic inflammation.

CONCLUSIONS

Peripheral blood counts are not reliable in characterising airway inflammation in severe asthmatic children exposed to high dose steroid therapy, therefore bronchoscopy with BAL should be considered.

Exhaled nitric oxide is related to bronchial eosinophilia and airway hyperresponsiveness to bradykinin in allergen-induced asthma exacerbation

Exhaled nitric oxide (FeNO) has been associated with bronchial eosinophilia and with airway hyperresponsiveness (AHR) in mild stable asthma. We previously demonstrated in a large project that allergen exposure is able to raise FeNO and to worsen AHR to bradykinin. We postulated that allergen-induced increase in FeNO could be related to heightened mucosal eosinophils and AHR to bradykinin in atopic asthma. We performed a new immunohistochemical analysis on bronchial biopsy specimens, previously obtained from the same large project, in order to assess the number of mucosal eosinophils (EG-2+ cell) and other inflammatory cells at 48 hours after diluent and allergen exposures. Inflammatory cell counts were related to FeNO and AHR to BK (expressed as logPD20 bradykinin). In 10 atopic mild asthmatics, we found that the numbers of EG-2+ and CD4+ cells in bronchial submucosa were significantly increased after allergen compared to the respective counts after diluent (p &#x003C; 0.01). EG-2+ cells in the bronchial submucosa were negatively correlated with logPD20 bradykinin only after allergen challenge (rho = -0.709, p = 0.027). We also found a positive strong correlation between EG-2+ cells and FeNO values in atopic asthmatics at 48 hours after both diluent (rho = 0.746, p = 0.017) and allergen (rho = 0.644, p = 0.049) challenge. FeNO values negatively correlated with responsiveness to bradykinin only after allergen challenge (rho = -0.675, p = 0.039). This study indicates that after allergen exposure heightened level of exhaled NO may reflect augmented airway eosinophilic inflammation and airway responsiveness to bradykinin indicating loss of asthma control.

[Improving dietary habits in the effective prevention of excess weight and obesity]

The new research survey "Okkio alla salute", conducted in children in the 3rd year of elementary school, has confermed the worrisome phenomenon of the high number of obese and overweight children. Therefore, it is necessary, also in light of the few available resources, to fight back against this phenomenon that has been demonstrated to be a cause of disabling illnesses in adults. There must therefore be collaboration between Departments of Prevention and Hygiene and Nutrition services (SIAN) to build valid and efficient pathways. In this presentation we describe some national projects carried out by various local health agencies to address this health problem.

IgE in childhood asthma: relevance of demographic characteristics and polysensitisation

BACKGROUND

Despite the therapeutic efficacy of the anti-IgE monoclonal antibody, the role of IgE in allergic asthma is still a matter of debate. This may be mostly relevant in childhood, where a wide range of total serum (s) IgE levels is often detected.

AIM

To evaluate whether the relationships between total or allergen-specific sIgE levels and the clinical markers of allergic inflammation and the pulmonary function values might be affected by the demographic characteristics of the patients or by the presence of multiple sensitisations to allergens.

METHODS

64 asthmatic children sensitised to house dust mites (HDM) were evaluated. The role of age, sex and multiple sensitisations was evaluated by multiple regression model (MRM) analysis.

RESULTS

Total and HDM-specific sIgE levels (Log) showed similar moderate-to-strong correlations with exhaled nitric oxide (FENO) and blood eosinophilia (Log) (p<0.0001) but not with forced vital capacity, forced expiratory volume in 1 s (FEV(1)), %FEV(1) change after salbutamol. The positive associations between total sIgE levels and Log FENO levels or Log blood eosinophilia were also detected by MRM analysis. Age brought a negative, although limited, contribution to FENO levels and blood eosinophilia (p<0.043). Positive similar associations were also detected between HDM-specific sIgE levels and FENO levels or blood eosinophilia; however, no significant contribution of age or of other covariates was detected.

CONCLUSION

In childhood allergic asthma, total and HDM-specific sIgE levels are tightly linked to markers of allergic inflammation but not to pulmonary functions. These relationships are weakly affected by age but not by sex or by the presence of multiple sensitisations.