Search

BackgroundComirnaty, Pfizer-BioNTech’s polyethylene-glycol (PEG)-containing Covid-19 vaccine, can cause hypersensitivity reactions (HSRs) in a small fraction of immunized people which can, very rarely, culminate in life-threatening anaphylaxis. A role of anti-PEG antibodies (Abs) has been proposed, but causality has not yet been proven in an animal model. This study aimed to provide such evidence using anti-PEG hyperimmune pigs (i.e., pigs displaying very high levels of anti-PEG Abs). We also sought to find evidence for the role of complement (C) activation and thromboxane A2 (TXA2) release in blood as contributing effects to anaphylaxis.MethodsPigs (n=6) were immunized with 0.1 mg/kg PEGylated liposome (Doxebo) i.v. the rise of anti-PEG IgG and IgM was measured in serial blood samples with ELISA. After 2-3 weeks, during the height of seroconversion, the animals were injected i.v. with 1/3 human vaccine dose (HVD) of Comirnaty, and the hemodynamic (PAP, SAP), cardiopulmonary (HR, EtCO2,), hematological parameters (WBC, granulocyte, lymphocyte, and platelet counts) and blood immune mediators (anti-PEG IgM and IgG Abs, C3a and TXA2) were measured as endpoints of HSRs.ResultsA week after immunization of 6 pigs with Doxebo, the level of anti-PEG IgM and IgG rose 5-10-thousands-fold in all animals, and they all developed anaphylactic shock to i.v. injection of 1/3 HVD of Comirnaty. The reaction, starting within 1 min, led to the abrupt decline of SAP along with maximal pulmonary hypertension, decreased pulse pressure amplitude, tachycardia, granulo- and thrombocytopenia, and paralleling rises of plasma C3a and TXB2 levels. These vaccine effects were not observed in non-immunized pigs.ConclusionsConsistent with previous studies with PEGylated nano-liposomes, these data show a causal role of anti-PEG Abs in the anaphylaxis to Comirnaty. The reaction involves C activation, and, hence, it represents C activation-related pseudo-allergy (CARPA). The setup provides the first large-animal model for mRNA-vaccine-induced anaphylaxis in humans.

The polyethylene-glycol (PEG)-containing Covid-19 vaccines can cause hypersensitivity reactions (HSRs), or rarely, life-threatening anaphylaxis. A causal role of anti-PEG antibodies (Abs) has been proposed, but not yet proven in humans. The 191 blood donors in this study included 10 women and 5 men who displayed HSRs to Comirnaty or Spikevax Covid-19 vaccines with 3 anaphylaxis. 118 donors had pre-vaccination anti-PEG IgG/IgM values as measured by ELISA, of which >98% were over background regardless of age, indicating the presence of these Abs in almost everyone. Their values varied over 2-3 orders of magnitude and displayed strong left-skewed distribution with 3-4% of subjects having >15-30-fold higher values than the respective median. First, or booster injections with both vaccines led to significant rises of anti-PEG IgG/IgM with >10-fold rises in about ∼10% of Comirnaty, and all Spikevax recipients, measured at different times after the injections. The anti-PEG Ab levels measured within 4-months after the HSRs were significantly higher than those in nonreactors. Serial testing of plasma (n=361 tests) showed the SARS-CoV-2 neutralization IgG to vary over a broad range, with a trend for biphasic dose dependence on anti-PEG Abs. The highest prevalence of anti-PEG Ab positivity in human blood reported to date represents new information which can most easily be rationalized by daily exposure to common PEG-containing medications and/or household items. The significantly higher, HSR-non-coincidental blood level of anti-PEG Abs in hypersensitivity reactor vs. non-reactors, taken together with relevant clinical and experimental data in the literature, suggest that anti-PEG Ab supercarrier people might be at increased risk for HSRs to PEG-containing vaccines, which themselves can induce these Abs via bystander immunogenicity. Our data also raise the possibility that anti-PEG Abs might also contribute to the reduction of these vaccines’ virus neutralization efficacy. Thus, screening for anti-PEG Ab supercarriers may identify people at risk for HSRs or reduced vaccine effectiveness.

Polyethylene glycol (PEG)-coated nanopharmaceuticals can cause mild to severe hypersensitivity reactions (HSRs), which can occasionally be life threatening or even lethal. The phenomenon represents an unsolved immune barrier to the use of these drugs, yet its mechanism is poorly understood. This study showed that a single i.v. injection in pigs of a low dose of PEGylated liposomes (Doxebo) induced a massive rise of anti-PEG IgM in blood, peaking at days 7–9 and declining over 6 weeks. Bolus injections of PEG-liposomes during seroconversion resulted in anaphylactoid shock (pseudo-anaphylaxis) within 2–3 min, although similar treatments of naı̈ve animals led to only mild hemodynamic disturbance. Parallel measurement of pulmonary arterial pressure (PAP) and sC5b-9 in blood, taken as measures of HSR and complement activation, respectively, showed a concordant rise of the two variables within 3 min and a decline within 15 min, suggesting a causal relationship between complement activation and pulmonary hypertension. We also observed a rapid decline of anti-PEG IgM in the blood within minutes, increased binding of PEGylated liposomes to IgM+ B cells in the spleen of immunized animals compared to control, and increased C3 conversion by PEGylated liposomes in the serum of immunized pigs. These observations taken together suggest rapid binding of anti-PEG IgM to PEGylated liposomes, leading to complement activation via the classical pathway, entailing anaphylactoid shock and accelerated blood clearance of liposome–IgM complexes. These data suggest that complement activation plays a causal role in severe HSRs to PEGylated nanomedicines and that pigs can be used as a hazard identification model to assess the risk of HSRs in preclinical safety studies. This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.

Tamás Mészáros,1,2,* Gergely Tibor Kozma,2,* Taro Shimizu,3 Koga Miyahara,3 Keren Turjeman,4 Tatsuhiro Ishida,3 Yechezkel Barenholz,4 Rudolf Urbanics,1,2 János Szebeni1,2,5 1Nanomedicine Research and Education Center, Department of Pathophysiology, Semmelweis University, Budapest, Hungary; 2SeroScience Ltd, Budapest, Hungary; 3Department of Pharmacokinetics and Biopharmaceutics, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan; 4Laboratory of Membrane and Liposome Research, Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel; 5Department of Nanobiotechnology and Regenerative Medicine, Faculty of Health, Miskolc University, Miskolc, Hungary *These authors contributed equally to this work Background: It has been proposed that many hypersensitivity reactions to nanopharmaceuticals represent complement (C)-activation-related pseudoallergy (CARPA), and that pigs provide a sensitive animal model to study the phenomenon. However, a recent study suggested that pulmonary hypertension, the pivotal symptom of porcine CARPA, is not mediated by C in cases of polystyrene nanoparticle (PS-NP)-induced reactions.Goals: To characterize PS-NPs and reexamine the contribution of CARPA to their pulmonary reactivity in pigs.Study design: C activation by 200, 500, and 750 nm (diameter) PS-NPs and their opsonization were measured in human and pig sera, respectively, and correlated with hemodynamic effects of the same NPs in pigs in vivo.Methods: Physicochemical characterization of PS-NPs included size, ζ-potential, cryo-transmission electron microscopy, and hydrophobicity analyses. C activation in human serum was measured by ELISA and opsonization of PS-NPs in pig serum by Western blot and flow cytometry. Pulmonary vasoactivity of PS-NPs was quantified in the porcine CARPA model.Results: PS-NPs are monodisperse, highly hydrophobic spheres with strong negative surface charge. In human serum, they caused size-dependent, significant rises in C3a, Bb, and sC5b-9, but not C4d. Exposure to pig serum led within minutes to deposition of C5b-9 and opsonic iC3b on the NPs, and opsonic iC3b fragments (C3dg, C3d) also appeared in serum. PS-NPs caused major hemodynamic changes in pigs, primarily pulmonary hypertension, on the same time scale (minutes) as iC3b fragmentation and opsonization proceeded. There was significant correlation between C activation by different PS-NPs in human serum and pulmonary hypertension in pigs.Conclusion: PS-NPs have extreme surface properties with no relevance to clinically used nanomedicines. They can activate C via the alternative pathway, entailing instantaneous opsonization of NPs in pig serum. Therefore, rather than being solely C-independent reactivity, the mechanism of PS-NP-induced hypersensitivity in pigs may involve C activation. These data are consistent with the “double-hit” concept of nanoparticle-induced hypersensitivity reactions involving both CARPA and C-independent pseudoallergy. Keywords: adverse drug reactions, immunotoxicity, nanoparticles, pseudoallergy, anaphylatoxins, PIM cells, phagocytosis

Liposomal drug delivery systems can protect pharmaceutical substances and control their release. Systemic administration of liposomes, however, often activate the innate immune system, resulting in hypersensitivity reactions. These pseudo-allergic reactions can be interpreted as activating the complement system. Complement activation destroys and removes foreign substances, either directly through opsonization and the formation of the membrane attack complex (MAC), or by activating leukocytes and initiating inflammatory responses via mediators, such as cytokines. In this study, we investigated the in vitro immune toxicity of the recently synthesized Rad-PC-Rad liposomes, analyzing the liposome-induced complement activation. In five human sera, Rad-PC-Rad liposomes did not induce activation, but in one serum high sensitivity via an alternative pathway was detected. Such a behavior in adverse phenomena is characteristic for patient-to-patient variation and, thus, the number of donors should be in the order of hundreds rather than tens – hence the present study based on six donors has preliminary character. In order to further prove the suitability of mechano-responsive Rad-PC-Rad liposomes for clinical trials, the production of pro-inflammatory cytokines was examined by human white blood cells. The concentrations of the pro-inflammatory cytokines IL-6, IL-12p70, TNF-α, and IL-1β induced by Rad-PC-Rad liposomal formulations incubated with whole blood samples were smaller or comparable to saline (negative control). Because of this favorable in vitro hemocompatibility, in vivo investigations using these mechano-responsive liposomes should be designed.

During the last decades, the prevalence of allergy has dramatically increased. Allergen-specific immunotherapy is the only currently available medical intervention that has the potential to affect the natural course of the disease, but there are still many questions and unmet needs hindering its widespread use to fulfill its treatment potential and maximize its benefits for the society. To provide a comprehensive phenome-wide overview in sublingual immunotherapy, using ragweed allergy as a target, we planned and carried out a longitudinal, prospective, observational, open-label study (DesensIT). In this paper we present challenges of using deep and comprehensive phenotypes embracing biological, clinical and patient-reported outcomes in allergen-specific immunotherapy and show how we designed the DesensIT project to optimize data collection, processing and evaluation.

In an attempt to develop a quantitative assay for supravesicular structures (SVS) – such as aggregates, fused liposomes or solid lipid particles – in liposome preparations, forward vs. side scattering of liposomal doxorubicin (Doxil/Caelyx) was analyzed by flow cytometry. Based on calibration with fluorescent latex beads, the size resolution was between about 500 and 1000 nm. Caelyx, just as structurally matched empty liposomes (Doxebo) produced dot plots clearly distinguishable from background, suggesting the presence of SVS in the above size region. A comparison of gated areas on the scattergrams obtained for different Caelyx preparations showed differences between current and expired samples, implying that SVS formation may be storage-time-dependent. Incubation of doxorubicin with Doxebo in a free drug and lipid concentration range that corresponds to that in Caelyx also led to varying SVS patterns, raising the possibility that free doxorubicin in Caelyx might contribute to SVS formation. Dynamic light scattering and transmission electron microscopic analysis of liposomes following gaiting and sorting of >500 nm particles from Caelyx confirmed the presence of SVS, providing independent evidence for their stable existence. Based on a rough estimation, the amount of SVS in Caelyx is some 60 billionth part of all liposomes. These observations raise the possibility that the presence of an exceedingly small fraction of >500 nm particles may be an intrinsic property of PEGylated small unilamellar liposomes, and that the described FACS analysis may be developed further as a quality assay for liposomal homogeneity.

Background: Galectin-9 (Gal-9) is a member of the growing family of β-galactoside-binding lectins. Gal-9 is an eosinophil chemoattractant and inducer of Th1 cell apoptosis. These effects suggest its potential role in the pathogenesis of asthma. Our aim was to study the expression of Gal-9 in an ovalbumin (OVA)-induced mouse model of allergic asthma. Methods: To investigate the significance of Gal-9 in allergic inflammation and airway hyperresponsiveness (AHR), a group of BALB/c mice was sensitized and challenged with OVA (GOVA). Another group of animals was allergized with OVA and also treated with dexamethasone (DEX) (GOVA+DEX). The control group (GPBS) received phosphate-buffered saline instead of OVA as placebo. Airway reactivity to intravenous methacholine was assessed. Results: The percentage of Gal-9-positive cells and their intracellular Gal-9 content and Th1/Th2 cytokine levels in the bronchoalveolar lavage (BAL) were determined by flow cytometry. Gal-9 mRNA expression and protein level were measured in the lung tissue by real-time RT-PCR and Western blot. In GOVA mice, airway inflammation and mucus hypersecretion developed. DEX treatment inhibited the main features of experimental asthma. The number of Gal-9-positive lymphocytes, eosinophil and neutrophil granulocytes and the levels of Th2 cytokines were higher in the BAL of GOVA compared to GPBS or GOVA+DEX mice. Moreover, Gal-9 protein level was elevated in the lungs of GOVA mice. Conclusions: These results suggest that Gal-9 plays a role as a mediator contributing to the development of allergic airway inflammation. Gal-9 may serve as a recruiter of eosinophil granulocytes and promoter of Th2 dominance.

To explore the role of complement (C) activation in the hypersensitivity reactions (HSRs) to some anticancer drugs, as well as the use of the C activation biomarkers (C

Serum levels of MCP-1 were measured in children with and without asthma in order to determine a possible correlation between the MCP-1-2518A/G polymorphism, serum levels of MCP-1 and asthma. Two groups of subjects -160 children with asthma and 158 healthy children were screened with a PCR-based genotyping assay. Serum MCP-1 level was measured by ELISA. The -2518G allele occurred at a significantly higher frequency in asthmatic children than in controls. The mean serum MCP-1 level was significantly lower in the asthmatic than in the control children. There was no significant association between the MCP-1 genotypes and the serum MCP-1 levels.

Chemokines play an important role in the pathophysiology of asthma and allergy. Recently, polymorphisms in the gene regulatory region of monocyte chemoattractant protein 1 (MCP-1) and in the promoter region of RANTES have been found; these polymorphisms increase the expression of the chemokines.We investigated whether the presence of the polymorphisms was associated with atopy or asthma and whether these alleles influenced the severity of asthma in affected individuals.Three groups of subjects-160 children with asthma (disease severity being classified according to the Global Initiative for Asthma guidelines, modified for children), 151 children with nonasthmatic but allergic phenotype, and 303 children without allergic or asthmatic disorders-were screened with a PCR-based assay for genotyping.The frequency of the -2518G polymorphism in the gene regulatory region of MCP-1 was significantly higher in asthmatic children than in controls (P.001; odds ratio [OR] = 2.0 [1.4-2.6]) and nonasthmatic atopic children (P.001; OR = 2.0 [1.4-2.9]). The MCP-1 G/G genotype correlated with asthma severity. In asthmatic children, the MCP-1 -2518G allele was also associated with an increased blood eosinophil level. The promoter polymorphisms in the RANTES gene did not have a detectable effect on the susceptibility to asthma or allergy or on the blood eosinophil count.In this cohort of children, there are associations between carrying G at -2518 of the MCP-1 gene regulatory region and the presence of asthma as well as between asthma severity and homozygosity for the G allele. In asthmatic children, the MCP-1 -2518G polymorphism correlated with increased eosinophil levels. This variant of MCP-1 might belong to the predictor gene set for asthma.

Histamine and vascular endothelial growth factor (VEGF) have been implicated in the pathogenesis of allergic asthma; they enhance inflammation, vascular permeability, and mucus secretion. Histamine was suggested to alter the level of VEGF via the H2 receptors. Here the authors have applied histidine decarboxylase gene-targeted (HDC(-/-)) mice, lacking histamine, to investigate the effect of histamine deficiency on VEGF expression in an animal model of asthma. HDC(-/-) and wild-type (WT) mice were sensitized and challenged with ovalbumin (OVA). VEGF mRNA expression and protein level were determined in the lung. Number of VEGF-positive immune cells of bronchoalveolar lavage (BAL) and their intracellular VEGF content were measured by flow cytometry. VEGF protein level in the lung and in the BAL cells was increased in OVA treated (HDC(-/-)(ova) as well as in WT(ova)) animals compared to their controls. However, there was no difference in the VEGF levels between HDC(-/-) or WT animals, either in the lung or in the BAL cells. In conclusion, increased VEGF production of the lung or BAL immune cells can be induced by allergen provocation independently from the genetic background of the animals. These data suggest that VEGF-mediated allergic processes can persist in the absence of histamine.

The function of apoptosis is to eliminate unnecessary or dangerous cells. The balance between production and death is important in the control of cell numbers within physiological ranges. Cells involved in allergic reactions may have altered apoptosis. The aim of this study was to examine the seasonal changes of programmed cell death in children with pollen allergy. We measured serum levels of soluble Fas (sFas) and soluble Fas ligand (sFasL), and examined whether there was any correlation between soluble apoptosis markers and development of asthma and or rhinitis in children with pollen allergy. We examined two groups of patients with ragweed pollen allergy. The first group consisted of 17 children with 'rhinitis only'. The second group consisted of 16 children with 'asthma + rhinitis'. For seasonal analysis we pooled the two groups and termed this the 'ragweed sensitive' group (n = 33, 5-18 yr, 25 boys, eight girls). Measurements (sFas and sFasL) were taken during the ragweed pollen allergy season, while control measurements were performed during the symptom-free period. There was no difference in sFas levels measured during and after [1941 +/- 68, 1963 +/- 83 pg/ml (mean+/-s.e.m, respectively)] the pollen season in the 'ragweed sensitive' group. The sFasL level showed seasonal change, which was significantly higher (p = 0.0086) in the symptomatic period compared to the symptom-free state (99 +/- 13 and 53 +/- 16 pg/ml, respectively). There was a difference between the 'rhinitis only' and the 'asthma + rhinitis' groups in the measured parameters of apoptosis. Children having allergic rhinitis combined with asthma had a significantly (p = 0.03) higher sFas level in the symptom-free state than the 'rhinitis only' group did (2115 +/- 156 and 1820 +/- 52 pg/ml, respectively). During the allergic symptom state the sFasL level of the 'asthma + rhinitis' group was significantly higher (p = 0.025) than that of the 'rhinitis only' group (125 +/- 20 and 75 +/- 14 pg/ml, respectively). In conclusion, the increased level of sFasL during the pollen season may signal its role in the pathogenesis of allergic airway diseases. There was no seasonal change in sFas levels in the examined ragweed allergic group, however in the symptomatic period we observed a diminished level of antiapoptotic factor (sFas) and an elevated level of proapoptotic factor (sFasL) if there was a combined disease with pollen allergic asthma. We suggest that there is a deviation in the apoptotic reaction in children that may increase the seasonal allergic inflammation.

Summary Allergic airway disease can be refractory to anti-inflammatory treatment, whose cause is unclarified. Therefore, in the present experiment, we have tested the hypothesis that co-exposure to lipopolysacharide (Lps) and allergen results in glucocorticoid-resistant eosinophil airway inflammation and hyper-responsiveness (AHR). Ovalbumin (Ova)-sensitized BALB/c mice were primed with 10 μg intranasal Lps 24 h before the start of Ova challenges (20 min on 3 consecutive days). Dexamethasone (5 mg/kg/day) was given on the last 2 days of Ova challenges. AHR, cellular build-up, cytokine and nitrite concentrations of bronchoalveolar lavage fluid (BALF) and lung histology were examined. To assess the role of iNOS-derived NO in airway responsiveness, mice were treated with a selective inhibitor of this enzyme (1400W) 2 h before AHR measurements. More severe eosinophil inflammation and higher nitrite formation were found in Lps-primed than in non-primed allergized mice. After Lps priming, AHR and concentrations of T-helper type 2 cytokines in BALF were decreased, but still remained significantly higher than in controls. Eosinophil inflammation was partially, while nitrite production and AHR were observed to be largely dexamethasone resistant in Lps-primed allergized animals. 1400W effectively and rapidly diminished the AHR in Ova-sensitized and challenged mice, but failed to affect it after Lps priming plus allergization. In conclusion, Lps inhalation may exaggerate eosinophil inflammation and reduce responsiveness to anti-inflammatory treatment in allergic airway disease.

Disturbed vascular endothelial growth factor (VEGF) production during early heart morphogenesis causes endocardial cushion malformation, which results in congenital heart disease (CHD). We tested whether functional VEGF -460T/C and +405G/C polymorphisms that have an impact on VEGF levels were associated with CHD.Dried blood samples were collected from 102 CHD children and 112 healthy control neonates. Genotyping was done with polymerase chain reaction-restriction fragment length polymorphism (VEGF +405G/C) and real-time polymerase chain reaction methods (VEGF -460T/C).VEGF -460C allele frequency was similar in control and CHD subjects. VEGF +405C allele was less prevalent in controls than in CHD subjects (0.21 vs 0.42, P.001). Having VEGF +405C presented increased risk for CHD (odds ratio [OR] 1.72, 95% CI 1.32-2.26). VEGF -460CT/+405CC allele associations did not occur in controls but in CHD patients (0% vs 13%, OR 2.26, 95% CI 1.93-2.64), whereas -460CT/+405GG allele association was more prevalent in controls (32% vs 16%, OR 0.58, 95% CI 0.37-0.89).VEGF gene and allele associations may be associated with increased risk of CHD.

Background Although several studies found associations between infection with Chlamydia pneumoniae and asthma, these were mainly restricted to the exacerbation of the symptoms in adults with known asthma. Data about the role of C pneumoniae in the initiation and development of asthma in children are controversial. Objective We investigated the role of C pneumoniae infection in 139 children with asthma, comparing them with 174 healthy control subjects. Furthermore, we studied the modifying effect of mannose-binding lectin (MBL) variant alleles on the susceptibility to asthma in children infected with C pneumoniae . Methods C pneumoniae –specific antibodies were measured by means of ELISA, and MBL genotypes were determined by means of PCR-RFLP. Results There were no significant differences in the percentage of children with positive results for C pneumoniae –specific antibodies between patients and control subjects. Among asthmatic children carrying variant MBL alleles, there were significantly more patients with positive results for C pneumoniae –specific IgG than among control children with variant MBL genotypes (63.7% vs 40.7% of asthmatic vs control children, respectively; odds ratio adjusted for age and sex, 2.21; 95% CI, 1.10-4.41; P = .02). Infected children with variant MBL alleles were found to have a higher risk of asthma development than infected children with normal MBL genotype. This risk was especially high in children with chronic or recurrent infection (positive results for both IgA and IgG; adjusted odds ratio, 5.38; 95% CI, 1.75-14.36; P = .01), but no increased risk was seen in children with current C pneumoniae infection (positive results for IgM). Conclusion This study indicates the important role of variant MBL alleles in the susceptibility to asthma in children infected with C pneumoniae. (J Allergy Clin Immunol 2003;112:729-34.)

Histamine is an important mediator released from activated mast cells provoked by allergen and has a substantial role in the pathophysiology of asthma. However, several lines of evidence indicate that histamine could also have important functions in the regulation of basic cell biological processes. We have used histidine decarboxylase gene-targeted (HDC-KO) mice, lacking histamine, to investigate the effect of histamine deficiency in an animal model of asthma. Our previous investigations revealed that HDC-KO mice had fewer mast cells with reduced granular content and defective degranulation characteristics. Ovalbumin (OVA)-sensitized and challenged HDC-KO mice had significantly reduced airway hyper-responsiveness, lung inflammation, bronchoalveolar lavage eosinophilia, and OVA-specific IgE compared with congenic wild-type littermates treated in the same way. Comparing the expression profiles of cytokines, the levels of IL-1alpha, IL-1beta, IL-4, IL-5, IL-6 and IFN-gamma were significantly lower in the HDC-KO mice in asthmatic late phase, indicating a significantly altered immune response to OVA provocation and challenge. Evaluation of chemokine gene expression revealed that OVA treatment caused elevation of both T(h)1- and T(h)2-type chemokines in wild-type mice, while the chemokine expression was polarized toward a T(h)1 response in HDC-KO mice. According to our results we can suggest that the possible causes of the reduced asthma symptoms in the HDC-KO mice may be the imperfect mast and eosinophil cell system, and an altered immune response to OVA provocation and challenge.

Background: Chemokines play an important role in the pathophysiology of atopic eczema/dermatitis syndrome (AEDS) and allergy. Recently polymorphisms in the promoter region of RANTES (regulated on activation normal T cell expressed and secreted) and in the gene regulatory region of MCP-1 (monocyte chemoattractant protein-1) have been found, which increase the expression of these chemokines. The − 403A allele of the RANTES promoter region was found associated with AEDS in German children. We investigated whether the presence of these polymorphisms was associated with AEDS or allergy in Hungarian children. Methods: One hundred and twenty-eight children with AEDS, 102 allergic children without AEDS and 303 children of comparable ages without allergic disorders were screened for genotype with a PCR-based assay. Results: There were no significant differences in the frequency of these polymorphisms, or in the distribution of genotypes between the groups. The total IgE concentration, the white blood cell count and the blood eosinophil cell count did not differ between the genotypes. Conclusion: In this cohort of Hungarian children there was no association between − 28G, and − 403A alleles in the RANTES promoter, − 2518G polymorphism in the distal regulatory region of the MCP-1 and AEDS, or allergy.

The rapid advances in genomic research have a major impact on biomedical sciences. In this review the authors summarize the current results of the genomic investigation of allergic diseases. From a genetic point of view allergy is multifactorial, which means that the susceptibility to the disease is determined by interactions between multiple genes, and involve important nongenetic factors such as the environment for their expression. There are two widespread methods for searching for disease susceptibility genes in allergy: (1) genome-wide search and (2) candidate gene association studies. Until now five groups have completed genome-wide searches for asthma, and almost 500 genetic linkage and association studies have reported more than 500 atopy and asthma loci throughout the genome. In this review we selected those results, which were consistently confirmed by several independent studies, or appeared particularly important, or interesting. On the basis of this, 9 chromosome regions can be associated with the susceptibility to allergic diseases: 2q, 5q31-q33, 6p21.3, 7q31, 11q13, 12q14.3-q24.31, 14q11.2-q13, 16p21, 17q11.2. According to the results of the human genome programs, and association studies, the authors discuss the possible roles of candidate genes found in these loci in the pathomechanism of allergy. Besides, the authors summarize briefly the results of pharmacogenomics, and animal linkage and genetics studies related to allergy.

Aims: To investigate whether the presence of the CCR5Δ32 allele was associated with atopy or asthma. Methods: A total of 118 children with asthma, 145 children with non-asthmatic, but allergic phenotype, and 303 children without allergic or asthmatic disorders were studied. Results: There were no significant differences in the frequency of CCR5Δ32, or in the distributions of genotypes between the groups. The relative eosinophil blood count was slightly lower in patients with heterozygous genotype, than in patients with wild type genotype. Conclusion: No association was found between the susceptibility of allergy or asthma and the functional deficient CCR5Δ32 allele.

Conjugation of polyethylene glycols (PEGs) to proteins or drug delivery nanosystems is a widely accepted method to increase the therapeutic index of complex nano-biopharmaceuticals. Nevertheless, these drugs and agents are often immunogenic, triggering the rise of anti-drug antibodies (ADAs). Among these ADAs, anti-PEG IgG and IgM were shown to account for efficacy loss due to accelerated blood clearance of the drug (ABC phenomenon) and hypersensitivity reactions (HSRs) entailing severe allergic symptoms with occasionally fatal anaphylaxis. In addition to recapitulating the basic information on PEG and its applications, this review expands on the physicochemical factors influencing its immunogenicity, the prevalence, features, mechanism of formation and detection of anti-PEG IgG and IgM and the mechanisms by which these antibodies (Abs) induce ABC and HSRs. In particular, we highlight the in vitro, animal and human data attesting to anti-PEG Ab-induced complement (C) activation as common underlying cause of both adverse effects. A main message is that correct measurement of anti-PEG Abs and individual proneness for C activation might predict the rise of adverse immune reactions to PEGylated drugs and thereby increase their efficacy and safety.

Cytokine storm (CS), an excessive release of proinflammatory cytokines upon overactivation of the innate immune system, came recently to the focus of interest because of its role in the life-threatening consequences of certain immune therapies and viral diseases, including CAR-T cell therapy and Covid-19. Because complement activation with subsequent anaphylatoxin release is in the core of innate immune stimulation, studying the relationship between complement activation and cytokine release in an in vitro CS model holds promise to better understand CS and identify new therapies against it. We used peripheral blood mononuclear cells (PBMCs) cultured in the presence of autologous serum to test the impact of complement activation and inhibition on cytokine release, testing the effects of liposomal amphotericin B (AmBisome), zymosan and bacterial lipopolysaccharide (LPS) as immune activators and heat inactivation of serum, EDTA and mini-factor H (mfH) as complement inhibitors. These activators induced significant rises of complement activation markers C3a, C4a, C5a, Ba, Bb, and sC5b-9 at 45 min of incubation, with or without ~5- to ~2,000-fold rises of IL-1α, IL-1β, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13 and TNFα at 6 and 18 h later. Inhibition of complement activation by the mentioned three methods had differential inhibition, or even stimulation of certain cytokines, among which effects a limited suppressive effect of mfH on IL-6 secretion and significant stimulation of IL-10 implies anti-CS and anti-inflammatory impacts. These findings suggest the utility of the model for in vitro studies on CS, and the potential clinical use of mfH against CS.