Subsets of Eosinophils in Asthma, a Challenge for Precise Treatment.

The existence of eosinophils was documented histopathologically in the first half of the 19th century. However, the term "eosinophils" was first used by Paul Ehrlich in 1878. Since their discovery and description, their existence has been associated with asthma, allergies, and antihelminthic immunity. Eosinophils may also be responsible for various possible tissue pathologies in many eosinophil-associated diseases. Since the beginning of the 21st century, the understanding of the nature of this cell population has undergone a fundamental reassessment, and in 2010, J. J. Lee proposed the concept of "LIAR" (Local Immunity And/or Remodeling/Repair), underlining the extensive immunoregulatory functions of eosinophils in the context of health and disease. It soon became apparent that mature eosinophils (in line with previous morphological studies) are not structurally, functionally, or immunologically homogeneous cell populations. On the contrary, these cells form subtypes characterized by their further development, immunophenotype, sensitivity to growth factors, localization, role and fate in tissues, and contribution to the pathogenesis of various diseases, including asthma. The eosinophil subsets were recently characterized as resident (rEos) and inflammatory (iEos) eosinophils. During the last 20 years, the biological therapy of eosinophil diseases, including asthma, has been significantly revolutionized. Treatment management has been improved through the enhancement of treatment effectiveness and a decrease in the adverse events associated with the formerly ultimately used systemic corticosteroids. However, as we observed from real-life data, the global treatment efficacy is still far from optimal. A fundamental condition, "sine qua non", for correct treatment management is a thorough evaluation of the inflammatory phenotype of the disease. We believe that a better understanding of eosinophils would lead to more precise diagnostics and classification of asthma subtypes, which could further improve treatment outcomes. The currently validated asthma biomarkers (eosinophil count, production of NO in exhaled breath, and IgE synthesis) are insufficient to unveil super-responders among all severe asthma patients and thus give only a blurred picture of the adepts for treatment. We propose an emerging approach consisting of a more precise characterization of pathogenic eosinophils in terms of the definition of their functional status or subset affiliation by flow cytometry. We believe that the effort to find new eosinophil-associated biomarkers and their rational use in treatment algorithms may ameliorate the response rate to biological therapy in patients with severe asthma.

Allergen immunotherapy in treating allergic eosinophilic asthma.

Currently, the approach to a patient with asthma is in accordance with personalized medicine wherein the decision on the treatment pathway is based on the type of asthmatic inflammation and other comorbidities that accompany asthma. For an allergic asthma patient, allergen immunotherapy (AIT), which has a disease-modifying effect and the potential to prevent further progression of allergic symptoms, is one of the treatment modalities. It is an effective treatment that, unlike pharmacotherapy, modifies the course of allergic respiratory diseases and induces allergen specific immune tolerance that persists for up to several years after treatment cessation. Therapeutic allergens of high quality, efficacy, and safety according to European regulatory authorities are an integral part of the treatment of respiratory allergies. It is a safe treatment option which still remains the only causal immuno¬modulatory therapy for allergic eosinophilic asthma.

Effect of individual allergen sensitization on omalizumab treatment outcomes in patients with severe allergic asthma determined using data from the Czech Anti-IgE Registry.

BACKGROUND: Omalizumab is an efficient drug for patients with uncontrolled severe allergic asthma (SAA). However, little is known about the differences in omalizumab treatment outcomes among patients with different types of atopic sensitization. Here, we assessed the effect of sensitization to individual allergens or their combinations on the outcomes of anti-IgE therapy in patients with SAA. METHODS: We performed a post hoc analysis of data of subgroups of patients enrolled in the Czech Anti-IgE Registry (CAR). The patients were evaluated at baseline and 16 weeks and 12 months after omalizumab treatment initiation. We analyzed the dependence of primary treatment outcomes [global evaluation of treatment effectiveness (GETE) after 16 weeks of treatment, a reduction in severe exacerbation rate (ER), and an improvement in the asthma control test (ACT) result during 12 months of treatment] and secondary outcomes [a reduction in systemic corticosteroid (SCS) use, an improvement in lung functions, and a fraction of exhaled nitric oxide] of patients with SAA treated with omalizumab for 12 months on sensitization to different perennial aeroallergens. We assessed sensitization to house dust mites, molds, and pets at baseline using skin prick tests and/or specific IgE measurement (semiquantitative evaluation). We compared polysensitized patients (sensitized to all tested allergens) with monosensitized (single positivity) or partially polysensitized patients (combined positivity but not to all allergens). RESULTS: We enrolled 279 patients (58.3% women, mean age 52.9 years). Omalizumab treatment presented an 82.8% response rate (according to GETE). It significantly reduced severe asthma exacerbations and SCS use, and improved the ACT result in 161 responders. We identified a subgroup of responders with distinct sensitization patterns (polysensitization to all tested perennial allergens) with higher odds of being responders (OR = 2.217, p = 0.02) and lower tendency to improve ACT result (OR 0.398, p = 0.023) and reduce ER (OR 0.431, p = 0.034) than non-polysensitized patients. CONCLUSIONS: The clinical benefit of sensitization for patients with SAA receiving omalizumab may be particularly dependent on sensitization pattern. Polysensitized patients showed a higher tendency to be responders (GETE), but a lower tendency to improve the ACT result and reduce ER than non-polysensitized patients.

Evolution of our view on the IgE molecule role in bronchial asthma and the clinical effect of its modulation by omalizumab: Where do we stand today?

Bronchial asthma is a heterogeneous disease whose definition and treatment are based on evidence of variable airway obstruction and airway inflammation. Despite the enormous increase in the amount of information on the pathogenesis of this disease, diagnosis is still an unresolved problem, as we still lack sensitive and specific biomarkers. On the other hand, at the turn of the 20th and 21st century, there was a rapid development of therapeutic modalities based on the principle of biological therapy. The first authorized drug matching these characteristics was omalizumab - a monoclonal antibody directed against immunoglobulin E (IgE). It has been used for the treatment of severe forms of bronchial asthma for more than 15 years, which is a sufficient time to acquire ways of its effective use and to assess whether the treatment with omalizumab has met our expectations. However, we continue to discover new and surprising facts about the effects of omalizumab treatment which leads to widening of therapeutic indications. In this work, a basic overview of the very complex role of the IgE molecule in the organism (with a special emphasis on allergic asthma) is discussed, and the most important practical and clinical consequences resulting from its modulation by targeted therapy with omalizumab are summarized.

Serum periostin levels in asthma patients in relation to omalizumab therapy and presence of chronic rhinosinusitis with nasal polyps.

INTRODUCTION: The serum periostin level is a promising biomarker of type 2- high inflammation pattern of bronchial asthma. It has been proven that serum periostin levels decrease in response to systemic and inhaled corticosteroid (ICS) therapy. However, we have only limited knowledge about changes in serum periostin levels reflecting omalizumab (OMA) treatment and other variables, such as chronic rhinosinusitis with nasal polyps (CRSwNP). AIM: To critically appraise clinically relevant parameters influencing periostin levels in asthma patients. MATERIAL AND METHODS: A pilot, cross-sectional, observational study to assess serum periostin levels of 48 asthma patients (38 treated by conventional therapy comprising ICS and 10 treated by ICS and OMA as an add-on therapy) with respect to asthma clinical traits, comorbidities and to other biomarkers of type 2-high asthma phenotype (total IgE, absolute and relative eosinophil count, eosinophilic cationic protein (ECP) and a fraction of exhaled NO (FeNO)). RESULTS: Serum periostin correlates with total IgE levels (Spearman rho = 0.364, p = 0.025) in a subgroup of conventionally treated patients, and with eosinophil count (Spearman rho = 0.401, p = 0.021) in a subgroup of patients with concurrent CRSwNP. Serum periostin levels were decreased in omalizumab-treated patients in comparison to conventionally treated patients (p = 0.025). This effect was remarkably apparent only if CRSwNP was not present (p = 0.005). Conversely, we measured elevated periostin levels in OMA-treated patients with concurrent CRSwNP (p = 0.017). CONCLUSIONS: Serum periostin production is significantly associated with treatment modality (omalizumab vs. conventional) and presence of CRSwNP. These variables need to be taken into account to interpret periostin levels accurately.

Real-world effectiveness and safety of omalizumab in patients with uncontrolled severe allergic asthma from the Czech Republic.

INTRODUCTION: This was a sub-group analysis of patients with uncontrolled persistent allergic asthma (AA) in the healthcare setting of the Czech Republic, from a global non-interventional, 2-year post-marketing, observational eXpeRience registry. AIM: To evaluate the real-life effectiveness and safety of omalizumab. MATERIAL AND METHODS: Patients with uncontrolled persistent AA (currently defined by the Global Initiative for Asthma (GINA) as uncontrolled severe AA) who started omalizumab treatment 15 weeks before inclusion in the registry were analysed for physicians' global evaluation of treatment effectiveness (GETE), asthma symptoms, corticosteroid use, exacerbation rate, asthma control, quality of life, healthcare utilisation and safety during a 24-month observation period. RESULTS: One hundred and fourteen patients from the Czech Republic were enrolled in the eXpeRience registry. A total of 88.9% of the patients were evaluated as responders to omalizumab according to the GETE assessment at week 16. From baseline to month 24: mean change in forced expiratory volume in 1 s (FEV1) was 137 ml and the daily dose of OCS decreased (11.6 mg to 6.4 mg prednisolone equivalent); the percentage of patients with no severe clinically significant exacerbations increased (29.5% to 95.1%); Asthma Control Test scores improved (12.4 to 17.3) and mean total number of days of asthma-related medical healthcare use decreased (6.8 days to 0.4 days). CONCLUSIONS: The results of this subgroup analysis support the evidence that add-on omalizumab therapy is effective and well tolerated for management of patients with uncontrolled persistent AA in the Czech Republic. Global evaluation of treatment effectiveness assessment is a reliable predictor of long-term response to omalizumab treatment.

Anaphylactic symptoms and anaphylactic shock.

Anaphylactic symptoms and anaphylactic shock are serious, rapidly developing and potentially fatal systemic reactions occurring after contact with the trigger, followed by release of a number of substances that affect vascular permeability, smooth muscle tone of blood vessels and bronchi with activation of the systemic inflammatory cascade. From a pathophysiological point of view, it can be an IgE-mediated immune response followed by massive release of biologically active mediators from mast cells and basophils (IgE dependent). If the mastocyt/basophil is degranulated via a direct IgE-free pathway, it is non-allergic (non-IgE dependent, anaphylactoid anaphylaxis). The diagnosis of anaphylaxis is determined on the basis of clinical criteria, taking into account the need to initiate therapy in a life-threatening condition without delay. Adrenaline is the first-line drug in the treatment of anaphylaxis and there is no contraindication to its use. Early provision of venous intake is essential for the patient to develop hypotension.

Small, Prospective, Observational, Pilot Study in Patients with Severe Asthma after Discontinuation of Omalizumab Treatment.

PURPOSE: Omalizumab has demonstrated clinical efficacy in severe allergic asthma by reducing exacerbation rates and increasing quality of life. However, data concerning its sustained effect after treatment discontinuation are still needed. METHODS: This analysis was an observational pilot study (simple within-subjects design) of 12 patients experiencing severe asthma, treated with omalizumab, for 1 year after treatment discontinuation. We prospectively analyzed clinical measurements (pulmonary functions, inhaled corticosteroid [ICS] doses, Asthma Control Test [ACT] scores, skin prick test [SPT] positivity, fraction of exhaled nitric oxide, and exacerbation rates) and laboratory test results (eosinophils and total immunoglobulin E levels) at the time of discontinuation and 6 and 12 months thereafter. Baseline data (before the treatment period; range, 11-61 months) were collected retrospectively. The treatment effect until discontinuation was calculated. To determine its persistence, repeated measures were compared with baseline levels and analyzed by using a general linear model for repeated measures or the Friedman ANOVA, and χ2 tests in case of normality assumption violation or frequencies. Post hoc analysis was applied by using a simple or repeated contrasts analysis or Wilcoxon signed rank test with Bonferroni correction. FINDINGS: We proved a significant reduction in ICS doses and SPT reactivity and an increase in ACT score during the retrospective treatment phase. Moreover, persistence of these statistically significant effects was recorded 6 months after treatment discontinuation. ACT score and ICS doses (but not SPT reactivity) remained improved for 12 months after discontinuation of omalizumab treatment. IMPLICATIONS: Omalizumab treatment exhibited sustained treatment benefit after its discontinuation for patients experiencing severe allergic asthma.

Scoring of the radiological picture of idiopathic interstitial pneumonia: a study to verify the reliability of the method.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a clinical form of usual interstitial pneumonia (UIP). Computed chest tomography (CT) has a fundamental role in the multidisciplinary diagnostics. However, it has not been verified if and how a subjective opinion of a radiologists or pneumologists can influence the assessment and overall diagnostic summary. PURPOSE: To verify the reliability of the scoring system. MATERIAL AND METHODS: Assessment of conformity of the radiological score of high-resolution CT (HRCT) of lungs in patients with IPF was performed by a group of radiologists and pneumologists. Personal data were blinded and the assessment was performed independently using the Dutka/Vasakova scoring system (modification of the Gay system). The final score of the single assessors was then evaluated by means of the paired Spearman's correlation and analysis of the principal components. RESULTS: Two principal components explaining cumulatively a 62% or 73% variability of the assessment of the single assessors were extracted during the analysis. The groups did not differ both in terms of specialty and experience with the assessment of the HRCT findings. CONCLUSION: According to our study, scoring of a radiological image using the Dutka/Vasakova system is a reliable method in the hands of experienced radiologists. Significant differences occur during the assessment performed by pneumologists especially during the evaluation of the alveolar changes.

[Cell death and its role in immunopathogenesis of infectious diseases]. / Bunecna smrt a jeji role v imunopatogenezi infekcnich chorob.

Cell death is still a matter of debate and scientific opinions have been challenged and are not uniform due to complexity of this issue. Recent research has brought some new evidence about the very subtle border between programmed cell death and necrosis. The concept of their mutual independence, broadly accepted for decades, is now significantly challenged. Lack of unified terminology led to the establishment of the Nomenclature Committee on Cell Death (NCCD) which provides recommendations for clear definition of distinct cell death programs. It also appeals for consistent application of this nomenclature in scientific literature. In this work, some keystone knowledge addressing three specific programmed cell death types - apoptosis, autophagic cell death, and pyroptosis which is recognized as a controversial cell death scenario on the border between programmed cell death and necrosis, is reviewed. These cell death scenarios are discussed in the context of pathogenesis of infectious diseases.

[Principles of macrophage resistance to intracellular parasites]. / Principy rezistence makrofagu vuci intracelularnim parazitum.

Intracellular parasitism is a phenomenon present in nature for more than one billion years. Its keystone is the intriguing ability of viruses and some bacteria to survive and multiply inside eukaryotic host cells and to parasitize on their metabolic machinery. According to the classical definition, germs are classified as intracellular parasites only if they are able to survive inside macrophages. However, the ability of germs to survive inside eukaryotic cells is much more common than it was expected earlier. Reaction of macrophages to invading microbes is the key point in the complex immunological resistance of the host. The outcome of the host is substantially linked to macrophage reactivity. For example, if an evading microbe with a replication time of 20 minutes survived inside a host for 24 hours without reaction of innate immunity, there would be more than 2 x 1021 microbes at the end of this period. It would be fatal for the host, indeed. The key activities of macrophages in the sense of protection against intracellular parasites are reviewed. Some mechanisms of microbial defence and some new approaches to clinical diagnosis of the functional status of cells of innate immunity are also discussed.

The effect of interferon-gamma and lipopolysaccharide on the growth of Francisella tularensis LVS in murine macrophage-like cell line J774.

BACKGROUND: Francisella tularensis, a causative agent of human tularemia, displaying the ability to proliferate inside the human cells. AIMS: To evaluate the growth potential of F. tularensis LVS strain in macrophage-like cell line J774 modulated by recombinant interferon gamma and E. coli derived lipopolysaccharide. RESULTS: Stimulation of J774 cells either by interferon-gamma or lipopolysaccharide alone, or especially in combination before infection F. tularensis, revealed protective effects. Higher concentrations of stimulating agents were needed to inhibit ongoing F. tularensis infection. CONCLUSIONS: Stimulation of J774 cell line by combination of interferon-gamma with lipopolysaccharide inhibits the intracellular growth of F. tularensis.

The multidrug resistance and apoptosis evaluation in acute myeloid leukemia cells after the in vitro doxorubicin treatment.

The apoptosis failure in cytostatic treatment of haemoblastosis is one of the means of chemoresistance. We were interested in the relationship of the after-doxorubicin-treatment-AML cells apoptosis and the immunophenotype, selected clinical and laboratory parameters, and also the P-gp, MRP, LRP, Bcl-2, Bax proteins expression. All analysis were evaluated with the flow cytometry method. To detect apoptotic cells in the sample, we used three methods: annexin test, TUNEL (TdT-mediated dUTP nick end labeling) test, and caspase 8 detection. After the cell cultivation the statisticaly important increase of apoptotic cells in the culture was apparent. The relation between the AML blast in vitro reaction and some clinical parameters such as the age of patient, white blood cell count, and blast percentage was also observed.

Rapid test for early detection of mycoplasma contamination of the continuous cell line J774.2.

The authors describe a rapid, simple and inexpensive method for the routine testing of mycoplasma contamination of the continuous mouse macrophage-like cell line J774.2 using specific anti-mouse monoclonal antibodies (antiCD14, antiCD80) and flow cytometry.

[The effect of polycyclic aromatic hydrocarbons to bone marrow]. / Ucinky polycyklických aromatických uhlovodíku na kostní dren.

Polycyclic aromatic hydrocarbons (PAH) represent a group of ubiquitous environmental pollutants. Their toxic effects are demonstrated mainly in tissues with high proliferation. The direct distribution of PAH in non-metabolized form to bone marrow and their biotransformation at this site to the toxic metabolites is necessary for demonstration of their toxic effect here. CYP1B1 that is constitutive expressed by stromal cells plays probably the main role in biotransformation of PAH in bone marrow. Reactions of toxic metabolites, development of oxidative stress and interference with intracellular calcium are ranged between the most important mechanisms of structural and functional changes of bone marrow after exposure to PAH. Pathological induction of apoptosis and malignant transformation of stem cells represent the concrete forms of bone marrow damage, caused by exposure to PAH. The bone marrow constitutes the central organ of hematopoiesis and the sites of production of cells of immune system. Its damage can bring therefore crucial health consequences for the whole organism.

Immunosuppressive effect of polycyclic aromatic hydrocarbons by induction of apoptosis of pre-B lymphocytes of bone marrow.

Polycyclic aromatic hydrocarbons (PAH) are ubiquitous environmental pollutants, distinguished by genotoxic, hepatotoxic, nephrotoxic and immunotoxic effects. Especially secondary toxicity after bioactivation by microsomal monooxygenases (dependent on cytochromes P450) is characteristic of them. The immunotoxic effect is the result of very global impact on immunological reactivity of an organism and immunosuppression by induction of apoptosis of pre-B lymphocytes represents one of its particular forms. It has been proved that the effect of PAH is caused mostly by the following mechanisms: enzymatic induction by the way of activation of AhR (Aromatic hydrocarbon Receptor); alteration of cellular DNA; development of oxidative stress; increase in the concentration of intercellular calcium and decline of activity of NF-kappaB (Nuclear Factor-kappa B). Most sensitive to these changes are particularly B-lymphocytic precursors and pre-B lymphocytes. Intensity of entire manifestations is also considerably dependent on the presence and intensity of mechanisms of active or passive resistance of cells.