Expansion of different subpopulations of CD26 ?/low T cells in allergic and non-allergic asthmatics

CD26 displays variable levels between effector (TH17 >> TH1 > TH2 > Treg) and naive/memory (memory > naive) CD4(+) T lymphocytes. Besides, IL-6/IL(-)6R is associated with TH17-differentiation and asthma severity. Allergic/atopic asthma (AA) is dominated by TH2 responses, while TH17 immunity might either modulate the TH2-dependent inflammation in AA or be an important mechanism boosting non-allergic asthma (NAA). Therefore, in this work we have compared the expression of CD26 and CD126 (IL-6Ralpha) in lymphocytes from different groups of donors: allergic (AA) and non-allergic (NAA) asthma, rhinitis, and healthy subjects. For this purpose, flow cytometry, haematological/biochemical, and in vitro proliferation assays were performed. Our results show a strong CD26-CD126 correlation and an over-representation of CD26(-) subsets with a highly-differentiated effector phenotype in AA (CD4(+)CD26(-/low) T cells) and NAA (CD4(-)CD26(-) gammadelta-T cells). In addition, we found that circulating levels of CD26 (sCD26) were reduced in both AA and NAA, while loss of CD126 expression on different leukocytes correlated with higher disease severity. Finally, selective inhibition of CD26-mRNA translation led to enhanced T cell proliferation in vitro. These findings support that CD26 down-modulation could play a role in facilitating the expansion of highly-differentiated effector T cell subsets in asthma

The CD14 (−159 C/T) SNP is associated with sCD14 levels and allergic asthma, but not with CD14 expression on monocytes

LPS-ligation to CD14/TLR-4 on monocytes/macrophages triggers the production of IL-12-family cytokines. IL12/18 promote TH1-differentiation, counteracting the TH2-driven asthma. Therefore, CD14 modulation could alter the TH2-differentiation and should be taken into account when studying asthma. To analyse the alteration in CD14 levels and its association with CD14 (−159 C/T) SNP (rs2569190) in Caucasian adults with stable allergic asthma, we performed a cross-sectional study (277 healthy subjects vs. 277 patients) where clinical parameters, CD14 values and the CD14 (−159 C/T) SNP were studied. Apart from typical biomarkers, we found an increment of neuron-specific enolase (NSE) in allergic asthma, probably linked to monocyte activity. Indeed, we evidenced increased monocyte numbers, but lower CD14 expression and normalised sCD14 values in patients. Moreover, we noticed an association of the T allele (P = 0.0162) and TT genotype (P = 0.0196) of the CD14 SNP with a decreased risk of allergic asthma and augmented sCD14 levels. In conclusion, monocyte CD14 expression and normalized sCD14 values were reduced in stable state asthmatics, and this could be related to the presence of an expanded CD14low monocyte subset. This study also demonstrates that the CD14 (−159 C/T) polymorphism is a risk factor for moderate-severe allergic asthma in adult CaucasiansThis study was funded by grants from Sociedad Española de Neumología y Cirugía Torácica, (SEPAR) (121/2012) and Instituto de Salud Carlos III, Ministerio de Economía y Competitividad (Fondo de Investigación Sanitaria, FIS; co-financed by European Union ERDF funds) (PI13/02046). JJNF is a recipient of a Xunta de Galicia Fellowship (Co-financed by European Social Fund (ESF))S

Association of Rhinitis With Asthma Prevalence and Severity

Multicenter study[Abstract] Asthma and rhinitis often co-exist in the same patient. Although some authors observed a higher prevalence and/or greater severity of asthma in patients with rhinitis, this view is not homogeneous and the debate continues. The aim of our study is to describe the prevalence of rhinitis in children and adolescents and to analyse their relationship with the prevalence of asthma. A multicentre study was conducted using the methodology of the International Study of Asthma and Allergies in Childhood (ISAAC). The target population of the study was all those school children aged 6-7 and 13-14 years from 6 of the main health catchment areas of Galicia (1.9 million inhabitants). The schools required were randomly selected, and all children in the targeted age ranges were included. Multiple logistic regression was used to obtain adjusted prevalence odds ratios (OR) between asthma symptoms of the schoolchildren and rhinitis prevalence. The results were adjusted for parental smoking habits, maternal education level, cat and dog exposure, and obesity. A total of 21,420 valid questionnaires were finally obtained. Rhinitis was associated with a significant increase in the prevalence of asthma in both age groups. The highest OR were 11.375 for exercise induced asthma (EIA) for children with recent rhinoconjunctivitis and 9.807 for children with recent rhinitis in 6-7 years old group. The prevalence OR's are higher in EIA and severe asthmatics. Rhinitis in children and adolescents is associated with a higher prevalence and severity of asthma.This work was funded by the Maria Jose Jove Foundatio

CD26 and Asthma: a Comprehensive Review

Asthma is a heterogeneous and chronic inflammatory family of disorders of the airways with increasing prevalence that results in recurrent and reversible bronchial obstruction and expiratory airflow limitation. These diseases arise from the interaction between environmental and genetic factors, which collaborate to cause increased susceptibility and severity. Many asthma susceptibility genes are linked to the immune system or encode enzymes like metalloproteases (e.g., ADAM-33) or serine proteases. The S9 family of serine proteases (prolyl oligopeptidases) is capable to process peptide bonds adjacent to proline, a kind of cleavage-resistant peptide bonds present in many growth factors, chemokines or cytokines that are important for asthma. Curiously, two serine proteases within the S9 family encoded by genes located on chromosome 2 appear to have a role in asthma: CD26/dipeptidyl peptidase 4 (DPP4) and DPP10. The aim of this review is to summarize the current knowledge about CD26 and to provide a structured overview of the numerous functions and implications that this versatile enzyme could have in this disease, especially after the detection of some secondary effects (e.g., viral nasopharyngitis) in type II diabetes mellitus patients (a subset with a certain risk of developing obesity-related asthma) upon CD26 inhibitory therapy

The CD14 (−159 C/T) SNP is associated with sCD14 levels and allergic asthma, but not with CD14 expression on monocytes

LPS-ligation to CD14/TLR-4 on monocytes/macrophages triggers the production of IL-12-family cytokines. IL12/18 promote TH-differentiation, counteracting the TH-driven asthma. Therefore, CD14 modulation could alter the TH-differentiation and should be taken into account when studying asthma. To analyse the alteration in CD14 levels and its association with CD14 (−159 C/T) SNP (rs2569190) in Caucasian adults with stable allergic asthma, we performed a cross-sectional study (277 healthy subjects vs. 277 patients) where clinical parameters, CD14 values and the CD14 (−159 C/T) SNP were studied. Apart from typical biomarkers, we found an increment of neuron-specific enolase (NSE) in allergic asthma, probably linked to monocyte activity. Indeed, we evidenced increased monocyte numbers, but lower CD14 expression and normalised sCD14 values in patients. Moreover, we noticed an association of the T allele (P = 0.0162) and TT genotype (P = 0.0196) of the CD14 SNP with a decreased risk of allergic asthma and augmented sCD14 levels. In conclusion, monocyte CD14 expression and normalized sCD14 values were reduced in stable state asthmatics, and this could be related to the presence of an expanded CD14 low monocyte subset. This study also demonstrates that the CD14 (−159 C/T) polymorphism is a risk factor for moderate-severe allergic asthma in adult Caucasian

Identification of Asthma Phenotypes in the Spanish MEGA Cohort Study Using Cluster Analysis

Introduction: The definition of asthma phenotypes has not been fully established, neither there are cluster studies showing homogeneous results to solidly establish clear phenotypes. The purpose of this study was to develop a classification algorithm based on unsupervised cluster analysis, identifying clusters that represent clinically relevant asthma phenotypes that may share asthma-related outcomes. Methods: We performed a multicentre prospective cohort study, including adult patients with asthma (N = 512) from the MEGA study (Mechanisms underlying the Genesis and evolution of Asthma). A standardised clinical history was completed for each patient. Cluster analysis was performed using the kernel k-groups algorithm. Results: Four clusters were identified. Cluster 1 (31.5% of subjects) includes adult-onset atopic patients with better lung function, lower BMI, good asthma control, low ICS dose, and few exacerbations. Cluster 2 (23.6%) is made of adolescent-onset atopic asthma patients with normal lung function, but low adherence to treatment (59% well-controlled) and smokers (48%). Cluster 3 (17.1%) includes adult-onset patients, mostly severe non-atopic, with overweight, the worse lung function and asthma control, and receiving combination of treatments. Cluster 4 (26.7%) consists of the elderly-onset patients, mostly female, atopic (64%), with high BMI and normal lung function, prevalence of smokers and comorbidities. Conclusion: We defined four phenotypes of asthma using unsupervised cluster analysis. These clusters are clinically relevant and differ from each other as regards FEV1, age of onset, age, BMI, atopy, asthma severity, exacerbations, control, social class, smoking and nasal polyps