Influence of antigen density and TLR ligands on preclinical efficacy of a VLP-based vaccine against peanut allergy

BACKGROUND

Virus-like particle (VLP) Peanut is a novel immunotherapeutic vaccine candidate for the treatment of peanut allergy. The active pharmaceutical ingredient represents cucumber mosaic VLPs (CuMVTT -VLPs) that are genetically fused with one of the major peanut allergens, Ara h 2 (CuMVTT -Ara h 2). We previously demonstrated the immunogenicity and the protective capacity of VLP Peanut-based immunization in a murine model for peanut allergy. Moreover, a Phase I clinical trial has been initiated using VLP Peanut material manufactured following a GMP-compliant manufacturing process. Key product characterization studies were undertaken here to understand the role and contribution of critical quality attributes that translate as predictive markers of immunogenicity and protective efficacy for clinical vaccine development.

METHOD

The role of prokaryotic RNA encapsulated within VLP Peanut on vaccine immunogenicity was assessed by producing a VLP Peanut batch with a reduced RNA content (VLP Peanut low RNA). Immunogenicity and peanut allergen challenge studies were conducted with VLP Peanut low RNA, as well as with VLP Peanut in WT and TLR 7 KO mice. Furthermore, mass spectrometry and SDS-PAGE based methods were used to determine Ara h 2 antigen density on the surface of VLP Peanut particles. This methodology was subsequently applied to investigate the relationship between Ara h 2 antigen density and immunogenicity of VLP Peanut.

RESULTS

A TLR 7 dependent formation of Ara h 2 specific high-avidity IgG antibodies, as well as a TLR 7 dependent change in the dominant IgG subclass, was observed following VLP Peanut vaccination, while total allergen-specific IgG remained relatively unaffected. Consistently, a missing TLR 7 signal caused only a weak decrease in allergen tolerability after vaccination. In contrast, a reduced RNA content for VLP Peanut resulted in diminished total Ara h 2 specific IgG responses, followed by a significant impairment in peanut allergen tolerability. The discrepant effect on allergen tolerance caused by an absent TLR 7 signal versus a reduced RNA content is explained by the observation that VLP Peanut-derived RNA not only stimulates TLR 7 but also TLR 3. Additionally, a strong correlation was observed between the number of Ara h 2 antigens displayed on the surface of VLP Peanut particles and the vaccine's immunogenicity and protective capacity.

CONCLUSIONS

Our findings demonstrate that prokaryotic RNA encapsulated within VLP Peanut, including antigen density of Ara h 2 on viral particles, are key contributors to the immunogenicity and protective capacity of the vaccine. Thus, antigenicity and RNA content are two critical quality attributes that need to be determined at the stage of manufacturing, providing robust information regarding the immunogenicity and protective capacity of VLP Peanut in the mouse which has translational relevance to the human setting.

Short-course subcutaneous treatment with PQ Grass strongly improves symptom and medication scores in grass allergy

BACKGROUND

A modified grass allergen subcutaneous immunotherapy (SCIT) product with MicroCrystalline Tyrosine and monophosphoryl lipid-A as an adjuvant system (Grass MATA MPL [PQ Grass]) is being developed as short-course treatment of grass-pollen allergic rhinitis (SAR) and/or rhinoconjunctivitis. We sought to evaluate the combined symptom and medication score (CSMS) of the optimized cumulative dose of 27,600 standardized units (SU) PQ Grass in a field setting prior to embarking on a pivotal Phase III trial.

METHODS

In this exploratory, randomized, double-blind, placebo-controlled trial subjects were enrolled across 14 sites (Germany and the United States of America). Six pre-seasonal subcutaneous injections of PQ Grass (using conventional or extended regimens) or placebo were administered to 119 subjects (aged 18-65 years) with moderate-to-severe SAR with or without asthma that was well-controlled. The primary efficacy endpoint was CSMS during peak grass pollen season (GPS). Secondary endpoints included Rhinoconjunctivitis Quality of Life Questionnaire standardized (RQLQ-S) and allergen-specific IgG4 response.

RESULTS

The mean CSMS compared to placebo was 33.1% (p = .0325) and 39.5% (p = .0112) for the conventional and extended regimens, respectively. An increase in IgG4 was shown for both regimens (p < .01) as well as an improvement in total RQLQ-S for the extended regimen (mean change -0.72, p = .02). Both regimens were well-tolerated.

CONCLUSIONS

This trial demonstrated a clinically relevant and statistically significant efficacy response to PQ Grass. Unprecedented effect sizes were reached for grass allergy of up to ≈40% compared to placebo for CSMS after only six PQ Grass injections. Both PQ Grass regimens were considered equally safe and well-tolerated. Based on enhanced efficacy profile extended regime will be progressed to the pivotal Phase III trial.

Ex Vivo Immunomodulatory Effects of Lactobacillus-, Lacticaseibacillus-, and Bifidobacterium-Containing Synbiotics on Human Peripheral Blood Mononuclear Cells and Monocyte-Derived Dendritic Cells in the Context of Grass Pollen Allergy

Sensing of the intestinal microbiota by the host immune system is important to induce protective immune responses. Hence, modification of the gut microbiota might be able to prevent or treat allergies, mediated by proinflammatory Th2 immune responses. The aim was to investigate the ex vivo immunomodulatory effects of the synbiotics Pollagen® and Kallergen®, containing the probiotic bacterial strains Lactobacillus, Lacticaseibacillus and Bifidobacterium, in the context of grass pollen allergy. Peripheral blood mononuclear cells (PBMCs) from grass pollen-allergic patients and healthy controls were stimulated with grass pollen extract (GPE) and synbiotics and Gata3 expression and cytokine secretion analyzed. Monocyte-derived dendritic cells (MoDCs) cells were matured in the presence of GPE and synbiotics, co-cultured with autologous naïve T cells and maturation markers and cytokine secretion analyzed. GPE stimulation of PBMCs from grass pollen-allergic patients resulted in a significant higher production of the Th2 cytokines IL-4, IL-5, IL-9 and IL-13 compared to healthy controls. Gata3+CD4+ T cell induction was independent of the allergic status. The synbiotics promoted IL-10 and IFN-γ secretion and downregulated the GPE-induced Th2-like phenotype. Co-culturing naïve T cells with MoDCs, matured in the presence of GPE and synbiotics, shifted the GPE-induced Th2 cytokine release towards Th1-Th17-promoting conditions in allergic subjects. The investigated synbiotics are effective in downregulating the GPE-induced Th2 immune response in PBMCs from grass pollen-allergic patients as well as in autologous MoDC-T cell stimulation assays. In addition to increased IL-10 release, the data indicates a shift from a Th2- to a more Th1- and Th17-like phenotype.

The holo beta-lactoglobulin lozenge reduces symptoms in cat allergy-Evaluation in an allergen exposure chamber and by titrated nasal allergen challenge

BACKGROUND

The allergists´ tool box in cat allergy management is limited. Clinical studies have shown that holo beta-lactoglobulin (holoBLG) can restore micronutritional deficits in atopic immune cells and alleviate allergic symptoms in a completely allergen-nonspecific manner. With this study, we aimed to provide proof of principle in cat allergy.

METHODS

A novel challenge protocol for cat allergy in a standardized ECARF allergen exposure chamber (AEC) was developed. In an open pilot study (NCT05455749), patients with clinically relevant cat allergy were provoked with cat allergen for 120 min in the AEC before and after a 3-month intervention phase (holoBLG lozenge 2x daily). Nasal, conjunctival, bronchial, and pruritus symptoms were scored every 10 min- constituting the total symptom score (TSS). Peak nasal inspiratory flow (PNIF) was measured every 30 min. In addition, a titrated nasal provocation test (NPT) was performed before and after the intervention. Primary endpoint was change in TSS at the end of final exposure compared to baseline. Secondary endpoints included changes in PNIF, NPT, and occurrence of late reactions up to 24 h after exposure.

RESULTS

35 patients (mean age: 40 years) completed the study. Compared to baseline, holoBLG supplementation resulted in significant improvement in median TSS of 50% (p < 0.001), as well as in median nasal flow by 20 L/min (p = 0.0035). 20% of patients reported late reactions after baseline exposure, but 0% after the final exposure.

CONCLUSIONS

Cat allergic patients profited from targeted micronutrition with the holoBLG lozenge. As previously seen in other allergies, holoBLG supplementation also induced immune resilience in cat allergies, resulting in significant symptom amelioration.

The next generation virus-like particle platform for the treatment of peanut allergy

BACKGROUND

Allergy to peanut is one of the leading causes of anaphylactic reactions among food allergic patients. Immunization against peanut allergy with a safe and protective vaccine holds a promise to induce durable protection against anaphylaxis caused by exposure to peanut. A novel vaccine candidate (VLP Peanut), based on virus-like particles (VLPs), is described here for the treatment of peanut allergy.

METHODS AND RESULTS

VLP Peanut consist of two proteins: a capsid subunit derived from Cucumber mosaic virus engineered with a universal T cell epitope (CuMV_TT ) and a CuMV_TT subunit fused with peanut allergen Ara h 2 (CuMV_TT -Ara h 2), forming mosaic VLPs. Immunizations with VLP Peanut in both naïve and peanut-sensitised mice resulted in a significant anti-Ara h 2 IgG response. Local and systemic protection induced by VLP Peanut were established in mouse models for peanut allergy following prophylactic, therapeutic and passive immunizations. Inhibition of FcγRIIb function resulted in a loss of protection, confirming the crucial role of the receptor in conferring cross protection against peanut allergens other than Ara h 2.

CONCLUSION

VLP Peanut can be delivered to peanut-sensitized mice without triggering allergic reactions, whilst remaining highly immunogenic and offering protection against all peanut allergens. In addition, vaccination ablates allergic symptoms upon allergen challenge. Moreover, the prophylactic immunization setting conferred the protection against subsequent peanut-induced anaphylaxis, showing the potential for preventive vaccination. This highlights the effectiveness of VLP Peanut as a prospective break-through immunotherapy vaccine candidate towards peanut allergy. VLP Peanut has now entered clinical development with the study PROTECT.

In situ delivery of nanoparticles formulated with micron-sized crystals protects from murine melanoma

Introduction

Intratumoral injections of novel therapeutics can activate tumor antigen-specific T cells for locoregional tumor control and may even induce durable systemic protection (against distant metastases) via recirculating T cells. Here we explored the possibility of a universal immunotherapy that promotes T-cell responses in situ and beyond, upon intratumoral injection of nanoparticles formulated with micron-sized crystals.

Methods

Cucumber mosaic virus-like particles containing a tetanus toxin peptide (CuMV_TT) were formulated with microcrystalline tyrosine (MCT) adjuvant and injected directly in B16F10 melanoma tumors. To further enhance immunogenicity, we loaded the nanoparticles with a TLR7/8 ligand and incorporated a universal tetanus toxin T-helper cell peptide. We assessed therapeutic efficacy and induction of local and systemic immune responses, including RNA sequencing, providing broad insight into the tumor microenvironment and correlates of protection.

Results

MCT crystals were successfully decorated with CuMV_TT nanoparticles. This ‘immune-enhancer’ formed immunogenic depots in injected tumors, enhanced polyfunctional CD8⁺ and CD4⁺ T cells, and inhibited B16F10 tumor growth locally and systemically. Local inflammation and immune responses were associated with upregulation of genes involved in complement activation and collagen formation.

Conclusions

Our new immune-enhancer turned immunologically cold tumors into hot ones and inhibited local and distant tumor growth. This type of immunotherapy does not require the identification of (patient–individual) relevant tumor antigens. It is well tolerated, non-infectious, and affordable, and can readily be upscaled for future clinical testing and broad application in melanoma and likely other solid tumors.

Major Allergen Content In Allergen Immunotherapy Products: The Limited Value of Numbers

The prevalence of allergic disorders drastically increased over the last 50 years that today they can be considered epidemic. At present, allergen-specific immunotherapy (AIT) is the only therapy targeting the underlying cause of allergic disorders, and its superior evidence is based on accumulated data from clinical trials and observational studies demonstrating efficacy and safety. However, several aspects remain unsolved, such as harmonization and standardization of manufacturing and quantification procedures across manufacturers, homogeneous reporting of strength, and also the establishment of international reference standards for many allergens. This article discusses the issues related to the measurement of major allergen content in AIT extracts, raising the question of whether comparison of products by different manufacturers are appropriate as basis to choose among the different AIT products. Allergen standardization in immunotherapy products is critical to ensure quality and thereby safety and efficacy. However, lack of harmonization in manufacturing process, allergen quantification (methodologies and references), national regulatory differences, clinical practice, and labeling shows that the comparison of AIT products solely based on major allergen amounts is not rationale and, in fact, impossible. Moreover, further inherent characteristics of products and their clinical use such as their state of extract modification, addition of adjuvant or adjuvant-system, route of administration (sublingual/subcutaneous) and cumulative dose as per posology (including the volume per administration) need to be taken into account, when rating the information given for a specific product. Finally, only convincing clinical data can serve as the product-specific evaluation, or the basis for cross-product comparability, for individual products.

Immunological effects of adjuvanted low-dose allergoid allergen-specific immunotherapy in experimental murine house dust mite allergy

BACKGROUND

Native allergen extracts or chemically modified allergoids are routinely used to induce allergen tolerance in allergen-specific immunotherapy (AIT), although mechanistic side-by-side studies are rare. It is paramount to balance optimal dose and allergenicity to achieve efficacy warranting safety. AIT safety and efficacy could be addressed by allergen dose reduction and/or use of allergoids and immunostimulatory adjuvants, respectively. In this study, immunological effects of experimental house dust mite (HDM) AIT were investigated applying high-dose HDM extract and low-dose HDM allergoids with and without the adjuvants microcrystalline tyrosine (MCT) and monophosphoryl lipid A (MPL) in a murine model of HDM allergy.

METHODS

Cellular, humoral, and clinical effects of the different AIT strategies were assessed applying a new experimental AIT model of murine allergic asthma based on physiological, adjuvant-free intranasal sensitization followed by subcutaneous AIT.

RESULTS

While low-dose allergoid and high-dose extract AIT demonstrated comparable potency to suppress allergic airway inflammation and Th2-type cytokine secretion of lung-resident lymphocytes and draining lymph node cells, low-dose allergoid AIT was less effective in inducing a potentially protective IgG1 response. Combining low-dose allergoid AIT with MCT or MCT and dose-adjusted MPL promoted Th1-inducing mechanisms and robust B-cell activation counterbalancing the allergic Th2 immune response.

CONCLUSION

Low allergen doses induce cellular and humoral mechanisms counteracting Th2-driven inflammation by using allergoids and dose-adjusted adjuvants. In light of safety and efficacy improvement, future therapeutic approaches may use low-dose allergoid strategies to drive cellular tolerance and adjuvants to modulate humoral responses.

Micronutritional supplementation with a holoBLG-based FSMP (food for special medical purposes)-lozenge alleviates allergic symptoms in BALB/c mice: Imitating the protective farm effect

BACKGROUND

Previously, the protective farm effect was imitated using the whey protein beta-lactoglobulin (BLG) that is spiked with iron-flavonoid complexes. Here, we formulated for clinical translation a lozenge as food for special medical purposes (FSMP) using catechin-iron complexes as ligands for BLG. The lozenge was tested in vitro and in a therapeutical BALB/c mice model.

METHODS

Binding of iron-catechin into BLG was confirmed by spectroscopy and docking calculations. Serum IgE binding of children allergic or tolerating milk was assessed to loaded (holo-) versus empty (apo-) BLG and for human mast cell degranulation. BLG and Bet v 1 double-sensitized mice were orally treated with the holoBLG or placebo lozenge, and immunologically analysed after systemic allergen challenge. Human PBMCs of pollen allergic subjects were flow cytometrically assessed after stimulation with apoBLG or holoBLG using catechin-iron complexes as ligands.

RESULTS

One major IgE and T cell epitope were masked by catechin-iron complexes, which impaired IgE binding of milk-allergic children and degranulation of mast cells. In mice, only supplementation with the holoBLG lozenge reduced clinical reactivity to BLG and Bet v 1, promoted Tregs, and suppressed antigen presentation. In allergic subjects, stimulation of PBMCs with holoBLG led to a significant increase of intracellular iron in circulating CD14+ cells with significantly lower expression of HLADR and CD86 compared to their stimulation with apoBLG.

CONCLUSION

The FSMP lozenge targeted antigen presenting cells and dampened immune activation in human immune cells and allergic mice in an antigen-non-specific manner, thereby conferring immune resilience against allergic symptoms.

Venom Immunotherapy: From Proteins to Product to Patient Protection

In this review, we outline and reflect on the important differences between allergen-specific immunotherapy for inhalant allergies (i.e., aeroallergens) and venom-specific immunotherapy (VIT), with a special focus on Venomil® Bee and Wasp. Venomil® is provided as a freeze-dried extract and a diluent to prepare a solution for injection for the treatment of patients with IgE-mediated allergies to bee and/or wasp venom and for evaluating the degree of sensitivity in a skin test. While the materials that make up the product have not changed, the suppliers of raw materials have changed over the years. Here, we consolidate relevant historical safety and efficacy studies that used products from shared manufacture supply profiles, i.e., products from Bayer or Hollister-Stier. We also consider the characterization and standardization of venom marker allergens, providing insights into manufacturing controls that have produced stable and consistent quality profiles over many years. Quality differences between products and their impacts on treatment outcomes have been a current topic of discussion and further research. Finally, we review the considerations surrounding the choice of depot adjuvant most suitable to augmenting VIT.

First evaluation of a symbiotic food supplement in an allergen exposure chamber in birch pollen allergic patients

Background

Allergic rhinitis/rhinoconjunctivitis is the most common immune disease worldwide, but still largely underestimated, underdiagnosed, and undertreated. Dysbiosis and reduced microbial diversity is linked to the development of allergies, and the immunomodulatory effects of pro- and prebiotics might be used to counteract microbiome dysbiosis in allergy. Adequate symbiotic (multi-strain pro-, plus prebiotic) supplementation can be suggested as a complementary approach in the management of allergic rhinitis.

Objective

The effects of the daily intake of a symbiotic food supplement (combination of Lactobacillus acidophilus NCFM and Bifidobacterium lactis BL-04 with Fructo-Oligosaccharides) for 4 months in birch pollen allergic rhinoconjunctivitis patients were investigated for the first time in an allergen exposure chamber (AEC) allowing standardised, reproducible pollen exposure before and after intake.

Methods

Eligible patients were exposed to birch pollen (8000 pollen/m³ for 120 min) at the GA²LEN AEC, at baseline (V1) and final visit (V3) outside the season. The Total Symptom Score (TSS) and the scores for nose, eye, bronchial system, and others were evaluated every 10 min during exposure. Other secondary endpoints were the changes in well-being, Peak Nasal Inspiratory Flow (PNIF), lung function parameters, and safety. Co-primary endpoints were differences in Total Nasal Symptom Score (TNSS) and TSS after 120 min of exposure between both visits. Temporal evolution of symptom scores were analysed in an exploratory way using linear mixed effects models.

Results

27 patients (mean age 45 years, 15% male) completed the study. Both co-primary endpoints showed significant improvement after intake of the symbiotic. Median TNSS and TSS were decreased 50% and 80% at 120 min (adjusted p-value = 0.025 and p < 0.01 respectively).

All four symptom scores and the personal well-being, improved to a clinically relevant extent over time, visible by a weaker increase in symptoms during 120 min of the final birch pollen exposure. No relevant differences were observed for PNIF, PEF, and spirometry. There were no airway obstructions or lung restrictions before and after both exposures. Late phase reactions after exposure were reduced after V3, documenting a better birch pollen tolerability of the patients. The safety and tolerability profile of the symbiotic food supplement was excellent, no adverse events (AEs) were observed.

Conclusions

This first evaluation of a symbiotic food supplement in an AEC in rhinoconjunctivitis patients with or without asthma induced by birch pollen revealed a significant beneficial effect, harnessing significant improvements of symptoms and well-being while maintaining an excellent safety and tolerability profile.

Shaping Modern Vaccines: Adjuvant Systems Using MicroCrystalline Tyrosine (MCT®)

The concept of adjuvants or adjuvant systems, used in vaccines, exploit evolutionary relationships associated with how the immune system may initially respond to a foreign antigen or pathogen, thus mimicking natural exposure. This is particularly relevant during the non-specific innate stage of the immune response; as such, the quality of this response may dictate specific adaptive responses and conferred memory/protection to that specific antigen or pathogen. Therefore, adjuvants may optimise this response in the most appropriate way for a specific disease. The most commonly used traditional adjuvants are aluminium salts; however, a biodegradable adjuvant, MCT®, was developed for application in the niche area of allergy immunotherapy (AIT), also in combination with a TLR-4 adjuvant-Monophosphoryl Lipid A (MPL®)-producing the first adjuvant system approach for AIT in the clinic. In the last decade, the use and effectiveness of MCT® across a variety of disease models in the preclinical setting highlight it as a promising platform for adjuvant systems, to help overcome the challenges of modern vaccines. A consequence of bringing together, for the first time, a unified view of MCT® mode-of-action from multiple experiments and adjuvant systems will help facilitate future rational design of vaccines while shaping their success.

Vaccine against peanut allergy based on engineered virus-like particles displaying single major peanut allergens

BACKGROUND

Peanut allergy is a severe and increasingly frequent disease with high medical, psychosocial, and economic burden for affected patients and wider society. A causal, safe, and effective therapy is not yet available.

OBJECTIVE

We sought to develop an immunogenic, protective, and nonreactogenic vaccine candidate against peanut allergy based on virus-like particles (VLPs) coupled to single peanut allergens.

METHODS

To generate vaccine candidates, extracts of roasted peanut (Ara R) or the single allergens Ara h 1 or Ara h 2 were coupled to immunologically optimized Cucumber Mosaic Virus-derived VLPs (CuMVtt). BALB/c mice were sensitized intraperitoneally with peanut extract absorbed to alum. Immunotherapy consisted of a single subcutaneous injection of CuMVtt coupled to Ara R, Ara h 1, or Ara h 2.

RESULTS

The vaccines CuMVtt-Ara R, CuMVtt-Ara h 1, and CuMVtt-Ara h 2 protected peanut-sensitized mice against anaphylaxis after intravenous challenge with the whole peanut extract. Vaccines did not cause allergic reactions in sensitized mice. CuMVtt-Ara h 1 was able to induce specific IgG antibodies, diminished local reactions after skin prick tests, and reduced the infiltration of the gastrointestinal tract by eosinophils and mast cells after oral challenge with peanut. The ability of CuMVtt-Ara h 1 to protect against challenge with the whole extract was mediated by IgG, as shown via passive IgG transfer. FcγRIIb was required for protection, indicating that immune complexes with single allergens were able to block the allergic response against the whole extract, consisting of a complex allergen mixture.

CONCLUSIONS

Our data suggest that vaccination using single peanut allergens displayed on CuMVtt may represent a novel therapy against peanut allergy with a favorable safety profile.

Correction: Zika Virus-Derived E-DIII Protein Displayed on Immunologically Optimized VLPs Induces Neutralizing Antibodies without Causing Enhancement of Dengue Virus Infection. Vaccines 2019, 7, 72

The authors wish to make the following correction to their paper [...].

Vaccination against Allergy: A Paradigm Shift?

Since the discovery that IgE antibodies mediate allergy, decades of research have unraveled complex mechanisms associated with conventional immunotherapy and the vital protagonists that shape 'immune tolerance' to allergens. Debate exists on what should constitute the dominant effector mechanism in driving rational drug designs for next-generation immunotherapies. As vaccine technology continues to advance, the development of novel vaccines in this area of continued medical need might stand on a threshold of breakthrough inspired by experiments by Dunbar on the passive vaccination of allergic animals more than 100 years ago. In this opinion article, we discuss both novel insights into IgG antibodies as the principle effector modality induced by specific immunotherapy and advances in antigen-carrier design that may catapult allergy treatment into our modern world.

Zika Virus-Derived E-DIII Protein Displayed on Immunologically Optimized VLPs Induces Neutralizing Antibodies without Causing Enhancement of Dengue Virus Infection

Zika virus (ZIKV) is a flavivirus similar to Dengue virus (DENV) in terms of transmission and clinical manifestations, and usually both viruses are found to co-circulate. ZIKV is usually transmitted by mosquitoes bites, but may also be transmitted by blood transfusion, via the maternal–foetal route, and sexually. After 2015, when the most extensive outbreak of ZIKV had occurred in Brazil and subsequently spread throughout the rest of South America, it became evident that ZIKV infection during the first trimester of pregnancy was associated with microcephaly and other neurological complications in newborns. As a result, the development of a vaccine against ZIKV became an urgent goal. A major issue with DENV vaccines, and therefore likely also with ZIKV vaccines, is the induction of antibodies that fail to neutralize the virus properly and cause antibody-dependent enhancement (ADE) of the infection instead. It has previously been shown that antibodies against the third domain of the envelope protein (EDIII) induces optimally neutralizing antibodies with no evidence for ADE for other viral strains. Therefore, we generated a ZIKV vaccine based on the EDIII domain displayed on the immunologically optimized Cucumber mosaic virus (CuMVtt) derived virus-like particles (VLPs) formulated in dioleoyl phosphatidylserine (DOPS) as adjuvant. The vaccine induced high levels of specific IgG after a single injection. The antibodies were able to neutralise ZIKV without enhancing infection by DENV in vitro. Thus, the here described vaccine based on EDIII displayed on VLPs was able to stimulate production of antibodies specifically neutralizing ZIKV without potentially enhancing disease caused by DENV.

Vaccination with nanoparticles combined with micro-adjuvants protects against cancer

BACKGROUND

Induction of strong T cell responses, in particular cytotoxic T cells, is a key for the generation of efficacious therapeutic cancer vaccines which yet, remains a major challenge for the vaccine developing world. Here we demonstrate that it is possible to harness the physiological properties of the lymphatic system to optimize the induction of a protective T cell response. Indeed, the lymphatic system sharply distinguishes between nanoscale and microscale particles. The former reaches the fenestrated lymphatic system via diffusion, while the latter either need to be transported by dendritic cells or form a local depot.

METHODS

Our previously developed cucumber-mosaic virus-derived nanoparticles termed (CuMV_TT-VLPs) incorporating a universal Tetanus toxoid epitope TT830-843 were assessed for their draining kinetics using stereomicroscopic imaging. A nano-vaccine has been generated by coupling p33 epitope as a model antigen to CuMV_TT-VLPs using bio-orthogonal Cu-free click chemistry. The CuMV_TT-p33 nano-sized vaccine has been next formulated with the micron-sized microcrystalline tyrosine (MCT) adjuvant and the formed depot effect was studied using confocal microscopy and trafficking experiments. The immunogenicity of the nanoparticles combined with the micron-sized adjuvant was next assessed in an aggressive transplanted murine melanoma model. The obtained results were compared to other commonly used adjuvants such as B type CpGs and Alum.

RESULTS

Our results showed that CuMV_TT-VLPs can efficiently and rapidly drain into the lymphatic system due to their nano-size of ~ 30 nm. However, formulating the nanoparticles with the micron-sized MCT adjuvant of ~ 5 μM resulted in a local depot for the nanoparticles and a longer exposure time for the immune system. The preclinical nano-vaccine CuMV_TT-p33 formulated with the micron-sized MCT adjuvant has enhanced the specific T cell response in the stringent B16F10p33 murine melanoma model. Furthermore, the micron-sized MCT adjuvant was as potent as B type CpGs and clearly superior to the commonly used Alum adjuvant when total CD8⁺, specific p33 T cell response or tumour protection were assessed.

CONCLUSION

The combination of nano- and micro-particles may optimally harness the physiological properties of the lymphatic system. Since the nanoparticles are well defined virus-like particles and the micron-sized adjuvant MCT has been used for decades in allergen-specific desensitization, this approach may readily be translated to the clinic.

Shortened up-dosing with sublingual immunotherapy drops containing tree allergens is well tolerated and elicits dose-dependent clinical effects during the first pollen season

Background

This study compared a rapid home-based up-dosing schedule for sublingual immunotherapy (SLIT) drops containing tree pollen allergens with two previously established schedules. Furthermore, the clinical effect of the SLIT was investigated with respect to patients’ first pollen season under treatment.

Methods

In this open-label, prospective, patient-preference, non-interventional study, local and systemic reactions were compared between three up-dosing groups using a SLIT formulation containing birch, alder, and hazel pollen extracts (ORALVAC^® Compact Bäume). Clinical improvement after patients’ first season under treatment was analysed using symptom scores, ARIA classification, symptom control, and the use of symptomatic medication and was compared with data from the previous, pre-treatment pollen season. As the real-life study design allowed no placebo group, the late-treated patients (co-seasonal) served as a control, and crowd-sourced symptom data from persons with hay fever were used from a free web-based online diary.

Results

In 33 study centres in Germany and Austria, 164 patients were included. The treatment was well tolerated, without difference between the groups during the up-dosing phase. At the end of the assessment, 96.1% rated the tolerability of the treatment as good or very good. Local reactions were mostly mild in severity and no serious adverse events occurred. Symptom scores decreased from the 2016 pollen season to the 2017 pollen season. As for the ARIA classification, 79.0% of patients had persistent, moderate-to-severe rhinitis before treatment, but only 18.6% had the same classification after treatment. In all, 62.4% of patients achieved symptom control, and 34.3% of patients required no symptomatic medication after treatment. The rhinoconjunctivitis score was 34.4% lower for pre-seasonal treatment initiation than for the control group. Crowd-sourced symptom load indices showed that the 2016 season caused slightly more symptoms; however, it is assumed that this difference of 0.3–0.5 (score range 0–10) was of less clinical relevance.

Conclusion

The treatment administered using the rapid home-based up-dosing schedule was safe and well tolerated. Symptom relief and reduction in medication use were observed during the first pollen season with SLIT.

Trial registration number

NCT03097432 (clinicaltrials.gov).

DOPS Adjuvant Confers Enhanced Protection against Malaria for VLP-TRAP Based Vaccines

Vaccination remains the most effective and essential prophylactic tool against infectious diseases. Enormous efforts have been made to develop effective vaccines against malaria but successes remain so far limited. Novel adjuvants may offer a significant advantage in the development of malaria vaccines, in particular if combined with inherently immunogenic platforms, such as virus-like particles (VLP). Dioleoyl phosphatidylserine (DOPS), which is expressed on the outer surface of apoptotic cells, represents a novel adjuvant candidate that may confer significant advantage over existing adjuvants, such as alum. In the current study we assessed the potential of DOPS to serve as an adjuvant in the development of a vaccine against malaria either alone or combined with VLP using Plasmodium falciparum thrombospondin-related adhesive protein (TRAP) as a target antigen. TRAP was chemically coupled to VLPs derived from the cucumber mosaic virus fused to a universal T cell epitope of tetanus toxin (CuMVtt). Mice were immunized with TRAP alone or formulated in alum or DOPS and compared to TRAP coupled to CuMVtt formulated in PBS or DOPS. Induced immune responses, in particular T cell responses, were assessed as the major protective effector cell population induced by TRAP. The protective capacity of the various formulations was assessed using a transgenic Plasmodium berghei expressing PfTRAP. All vaccine formulations using adjuvants and/or VLP increased humoral and T cell immunogenicity for PfTRAP compared to the antigen alone. Display on VLPs, in particular if formulated with DOPS, induced the strongest and most protective immune response. Thus, the combination of VLP with DOPS may harness properties of both immunogenic components and optimally enhance induction of protective immune responses.

Aluminium (Al) speciation in serum and urine after subcutaneous venom immunotherapy with Al as adjuvant

BACKGROUND

Aluminium is associated with disorders and is the commonly used vaccine adjuvant. Understanding the mechanisms of how Al is transported, metabolized or of its toxicity depends on the knowledge of Al-interactions with bioligands, i.e. Al-species. Al-speciation in serum is difficult because of low concentration and the risk of exogenous Al contamination. Furthermore, Al-measurements may be hampered according to various interferences. This study aims for developing quality controlled protocols for reliable Al- and Al-species determination and for investigating probable differences in Al (-speciation) after Al-containing subcutaneous immunotherapy (SIT).

METHODS

Sample donors were recruited either for the control group ("class-0", they never had been treated with SIT containing an Al-depot extract) or for the SIT-group ("class-1", they previously had been treated with SIT for insect venom allergy with an Al-depot extract). Blood was drawn for medical reasons and serum prepared. Additionally, some sample donors collected 24-h-urine. They had been informed (and they consented) about the scientific use of their samples. The study was approved by the ethic committee of the "Medical Association Westphalia-Lippe" and of the University of Münster, evaluating the study positively (No. 2013-667-f-S). We applied quality controlled sample preparation and interference-free Al detection by ICP sectorfield-mass spectrometry. Al-species were analysed using size-exclusion-chromatography-ICP-qMS.

FINDINGS

Al-concentrations or speciation in urine samples showed no differences between class-0 and class-1. Al-citrate was the main uric Al-species. In serum elevated Al-concentrations were found for both classes, with class-1 samples being significantly higher than class-0 (p = 0.041), but class-0 samples being approximately 10-fold too high compared to reference values from non-exposed persons. We identified gel-monovettes as contamination source. In contamination-free samples from HNO₃-prewashed gel-free monovettes (n = 27) there was no difference in the serum Al concentration between the two patient groups (p = 0.669) INTERPRETATION: Thorough cleaning of sample preparation ware and use of gel-free monovettes is decisive for an accurate Al analysis in serum. Without these steps, wrong analysis and wrong conclusions are likely. We conclude that gel-monovettes are unsuitable for blood sampling with subsequent Al-analysis. Whether Al in serum is elevated after SIT treatment containing an Al-depot extract, or not, remains inconclusive as the non-contaminated sample size was small.

Virus-like particles (VLP) in prophylaxis and immunotherapy of allergic diseases

BACKGROUND

Apart from active allergen avoidance, immunotherapy is regarded as the most effective form of treatment available for type I allergies. Such treatments involve the administration of allergen preparations in various forms and by various routes. Virus-like particles (VLPs) offer a very effective platform for immunization with the allergen and are characterized by high immunogenicity, low allergenicity and high clinical efficacy. Formulations that include Toll-like receptor ligands, T cell stimulatory epitopes and/or depot-forming adjuvants appear to enhance activation of the relevant immune cells. Short nucleotide sequences including CpG motifs have also been intensively explored as potent stimulators of dendritic cells and B cells.

METHODS

The present paper is based on a systematic literature search in PubMed and MEDLINE, and focuses on the pertinent immunological processes and on clinical data relating to use of VLPs and CpG motifs for the treatment of allergic rhinitis (AR).

RESULTS

Many published studies have reported positive clinical results following administration of VLPs, either alone or in combination with CpG motifs and, in some cases, even in the absence of the allergen-specific allergen.

CONCLUSIONS

These results indicate that VLPs modulate immune responses in ways which underline their exceptional promise as a platform for the immunotherapy of allergic disorders. However, clinical evaluations remain limited, and further large-scale and longer-term studies will be necessary to substantiate the efficacy and safety of these novel therapies.

Microcrystalline Tyrosine and Aluminum as Adjuvants in Allergen-Specific Immunotherapy Protect from IgE-Mediated Reactivity in Mouse Models and Act Independently of Inflammasome and TLR Signaling

Allergen immunotherapy (AIT) is the only modality that can modify immune responses to allergen exposure, but therapeutic coverage is low. One strategy to improve AIT safety and efficacy is the use of new or improved adjuvants. This study investigates immune responses produced by microcrystalline tyrosine (MCT)–based vaccines as compared with conventional aluminum hydroxide (alum). Wild-type, immune-signaling–deficient, and TCR-transgenic mice were treated with different Ags (e.g., OVA and cat dander Fel d 1), plus MCT or alum as depot adjuvants. Specific Ab responses in serum were measured by ELISA, whereas cytokine secretion was measured both in culture supernatants by ELISA or by flow cytometry of spleen cells. Upon initiation of AIT in allergic mice, body temperature and further clinical signs were used as indicators for anaphylaxis. Overall, MCT and alum induced comparable B and T cell responses, which were independent of TLR signaling. Alum induced stronger IgE and IL-4 secretion than MCT. MCT and alum induced caspase-dependent IL-1β secretion in human monocytes in vitro, but inflammasome activation had no functional effect on inflammatory and Ab responses measured in vivo. In sensitized mice, AIT with MCT-adjuvanted allergens caused fewer anaphylactic reactions compared with alum-adjuvanted allergens. As depot adjuvants, MCT and alum are comparably effective in strength and mechanism of Ag-specific IgG induction and induction of T cell responses. The biocompatible and biodegradable MCT seems therefore a suitable alternative adjuvant to alum-based vaccines and AIT.

Microcrystalline Tyrosine (MCT®): A Depot Adjuvant in Licensed Allergy Immunotherapy Offers New Opportunities in Malaria

Microcrystalline Tyrosine (MCT^®) is a widely used proprietary depot excipient in specific immunotherapy for allergy. In the current study we assessed the potential of MCT to serve as an adjuvant in the development of a vaccine against malaria. To this end, we formulated the circumsporozoite protein (CSP) of P. vivax in MCT and compared the induced immune responses to CSP formulated in PBS or Alum. Both MCT and Alum strongly increased immunogenicity of CSP compared to PBS in both C57BL/6 and BALB/c mice. Challenge studies in mice using a chimeric P. bergei expressing CSP of P. vivax demonstrated clinically improved symptoms of malaria with CSP formulated in both MCT and Alum; protection was, however, more pronounced if CSP was formulated in MCT. Hence, MCT may be an attractive biodegradable adjuvant useful for the development of novel prophylactic vaccines.

The grass pollen season 2015: a proof of concept multi-approach study in three different European cities

Background

Grasses release the most widespread aeroallergens with considerable sensitization rates, while different species produce several pollen concentration peaks throughout the season. This study analyzed the prevalence of grass species in three different European city areas and compared the flowering period of these species with daily pollen concentrations and the symptom loads of grass pollen allergy sufferers.

Methods

The most prevalent grass species in Vienna (Austria), Berlin (Germany) and Turku (Finland) were studied and examined by use of three different approaches: phenology, pollen monitoring and symptom load evaluation. A mobile pollen exposure chamber was employed to observe reaction patterns of grass pollen allergy sufferers to three common grass species evaluated in this study versus placebo.

Results

Common meadow grass (Poa pratensis) and the fescue grass species (Festuca spp.) are important contributors within the grass pollen season. The pollination period of orchard grass (Dactylis glomerata) and false-oat grass (Arrhenatherum elatius) indicated a greater importance in Berlin and Vienna, whereas a broader spectrum of grass species contributed in Turku to the main pollen season. The standardized provocation induced a nasal symptom load, reduction in nasal flow and increased secretion, in contrary to the placebo control group in grass pollen allergic subjects.

Conclusion

The phenological observations, pollen measurements and symptom data evaluation provided unique insights into the contribution of multiple grass species in different European regions. All investigated grass species in the provocation induced rhinitis symptoms of comparable significance, with some degree of variation in symptom patterns.

The grass pollen season 2014 in Vienna: A pilot study combining phenology, aerobiology and symptom data

BACKGROUND

Grasses (Poaceae) are one of the largest plant families and are distributed worldwide. Grass pollen allergy is one of the most important pollen allergies affecting large parts of the population worldwide. The grass pollen season itself is special since it is caused by the flowering of various grass species that present unique profiles of allergenicity, which assumingly plays a significant role and impact on grass pollen sensitization profiles for the allergy sufferer. The aim of this study, conducted in Vienna, 2014, was to analyze the possible contribution of prevalent grass species to the grass pollen season and to the symptom load of grass allergy sufferers.

METHODS

This was the first study that combines phenological observations (i.e. grass species and their flowering periods) with aerobiological measurements (i.e. daily grass pollen concentrations) in concert with allergic symptoms from local users of the Patient's Hayfever Diary (symptom load index calculation).

RESULTS

Both the pollen concentrations and the symptom levels were higher in the first half of the main grass pollen season and therefore show the highest impact on pollen allergy sufferers. Of important note were the following species that are widely distributed in Vienna: Kentucky bluegrass (Poa pratensis), orchard grass (Dactylis glomerata), false oat-grass (Arrhenatherum elatius), fescue grass (Festuca sp.) and perennial rye-grass (Lolium perenne).

CONCLUSION

Monitoring different grass species provided evidence for varying contribution in pollination across the main grass pollen season and highlighted the significance this impact may have on pollen allergy sufferers.

Cytokine patterns in nasal secretion of non-atopic patients distinguish between chronic rhinosinusitis with or without nasal polys

BACKGROUND

Being one of the most common nasal diseases, chronic rhinosinusitis (CRS) is subdivided into CRS with nasal polyps (NP) and CRS without nasal polyps (CRSsNP). CRSsNP presents itself with a TH1 milieu and neutrophil infiltration, while NP is characterised by a mixed TH1/TH2 profile and an influx of predominantly eosinophils, plasma cells and mast cells. For the purpose of discovering disease-specific cytokine profiles, the present study compares levels of mediators and cytokines in nasal secretions between CRSsNP, NP, and healthy controls.

METHODS

The study included 45 participants suffering from NP, 48 suffering from CRSsNP and 48 healthy controls. Allergic rhinitis constituted an exclusion criterion. Nasal secretions, sampled using the cotton wool method, were analysed for IL-4, IL-5, IL-10, IL-12, IL-13, IL-17, IL-8, GM-CSF, G-CSF, IFN-γ, MCP-1, MIP-1α, MIP-1β, eotaxin, and RANTES, and for ECP and tryptase, using Bio-Plex Cytokine assay or ELISA, respectively.

RESULTS

Elevated levels of IL-5, IL-17, G-CSF, MCP-1, MIP-1α, MIP-1β, ECP, and tryptase, as well as decreased levels of IL-10, IL-12, IL-13, and IFN-γ were detected in NP. CRSsNP presented increased levels of RANTES and MIP-1β while IL-13 was decreased. No differences between the three groups were found for IL-4, IL-8, GM-CSF, and eotaxin.

CONCLUSIONS

The present work suggests a disequilibrium of TH1 and TH2, together with a down-regulation of regulatory T lymphocytes and up-regulated TH17 in NP. Moreover, elevated levels of diverse mediators represent the activation of various inflammatory cells in this disease entity. The inflammation in CRSsNP, however, is only weakly depicted in nasal secretions. Therefore, cytokines in nasal secretions may provide helpful information for differential diagnosis.

In vitro evidence for efficacy in food intolerance for the multispecies probiotic formulation Ecologic® Tolerance (Syngut™)

The beneficial effects of probiotics are currently the subject of extensive studies in health and medical research. The aim of this research was to specifically design a new probiotic formulation for supplementation in people suffering from food intolerance. The selection of strains was focussed on the capacity to influence mechanisms of action that are important in development of food intolerance with the following parameters measure: in vitro capacity to produce β-galactosidase, in vitro strengthening of the epithelial barrier, in vitro stimulation of cytokines produced by regulatory T cells, in addition to assessing fundamental quality criteria (stability, gastrointestinal (GI)-survival, multispecies concept, allergen-free). Ecologic®Tolerance/Syngut™ was subsequently developed consisting of a multispecies concept using 4 different probiotic strains (Bifidobacterium lactis W51, Lactobacillus acidophilus W22, Lactobacillus plantarum W21 and Lactococcus lactis W19). Each of these strains demonstrated ability to survive the GI-tract and strain specific effects in producing β-galactosidase, strengthening the gut barrier function after immunological-induced stress and inhibiting Th2 cytokines (IL-4, IL-5 and IL-13 (≥50%), in addition to stimulating interleukin-10 levels; thus, providing in vitro evidence for the efficacy of the selected strains to provide beneficial effects in patients suffering from food intolerance.

Cytokine profiles in nasal fluid of patients with seasonal or persistent allergic rhinitis

Background

New therapeutic approaches with biologic agents such as anti-cytokine antibodies are currently on trial for the treatment of asthma, rhinosinusitis or allergic diseases necessitating patient selection by biomarkers. Allergic rhinitis (AR), affecting about 20 % of the Canadian population, is an inflammatory disease characterised by a disequilibrium of T-lymphocytes and tissue eosinophilia. Aim of the present study was to describe distinct cytokine patterns in nasal secretion between seasonal and perennial AR (SAR/PAR), and healthy controls by comparing cytokines regulating T-cells or stimulating inflammatory cells, and chemokines.

Methods

Nasal secretions of 44 participants suffering from SAR, 45 participants with PAR and 48 healthy controls were gained using the cotton wool method, and analysed for IL-1β, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, GM-CSF, G-CSF, IFN-γ, MCP-1, MIP-1α, MIP-1β, eotaxin, and RANTES by Bio-Plex Cytokine Assay as well as for ECP and tryptase by UniCAP-FEIA.

Results

Participants with SAR or PAR presented elevated levels of tryptase, ECP, MCP-1, and MIP-1β, while values of GM-CSF, G-CSF, IL-1β, and IL-6 did not differ from the controls. Increased levels of IL-5, eotaxin, MIP-1α, and IL-17 and decreased levels of IFN-γ, IL-12 and IL-10 were found in SAR only. RANTES was elevated in SAR in comparison to PAR. Interestingly, we found reduced levels of IL-4 in PAR and of IL-13 in SAR.

Conclusions

Elevated levels of proinflammatory cytokines were seen in both disease entities. They were, however, more pronounced in SAR, indicating a higher degree of inflammation. This study suggests a downregulation of T_H1 and T_reg-lymphocytes and an upregulation of T_H17 in SAR. Moreover, the results display a prominent role of eosinophils and mast cells in AR. The observed distinct cytokine profiles in nasal secretion may prove useful as a diagnostic tool helping to match patients to antibody therapies.

Aluminium in allergen-specific subcutaneous immunotherapy--a German perspective

We are living in an "aluminium age" with increasing bioavailability of the metal for approximately 125 years, contributing significantly to the aluminium body burden of humans. Over the course of life, aluminium accumulates and is stored predominantly in the lungs, bones, liver, kidneys and brain. The toxicity of aluminium in humans is briefly summarised, highlighting links and possible causal relationships between a high aluminium body burden and a number of neurological disorders and disease states. Aluminium salts have been used as depot-adjuvants successfully in essential prophylactic vaccinations for almost 100 years, with a convincing positive benefit-risk assessment which remains unchanged. However, allergen-specific immunotherapy commonly consists of administering a long-course programme of subcutaneous injections using preparations of relevant allergens. Regulatory authorities currently set aluminium limits for vaccines per dose, rather than per treatment course. Unlike prophylactic vaccinations, numerous injections with higher proportions of aluminium-adjuvant per injection are applied in subcutaneous immunotherapy (SCIT) and will significantly contribute to a higher cumulative life dose of aluminium. While the human body may cope robustly with a daily aluminium overload from the environment, regulatory cumulative threshold values in immunotherapy need further addressing. Based on the current literature, predisposing an individual to an unusually high level of aluminium, such as through subcutaneous immunotherapy, has the potential to form focal accumulations in the body with the propensity to exert forms of toxicity. Particularly in relation to longer-term health effects, the safety of aluminium adjuvants in immunotherapy remains unchallenged by health authorities - evoking the need for more consideration, guidance, and transparency on what is known and not known about its safety in long-course therapy and what measures can be taken to prevent or minimise its risks. The possibility of providing an effective means of measuring aluminium accumulation in patients undergoing long-term SCIT treatment as well as reducing their aluminium body burden is discussed.

Probiotics in the treatment of chronic rhinoconjunctivitis and chronic rhinosinusitis

Chronic rhinitis and rhinosinusitis (CRS) are relevant health conditions affecting significant percentages of the western population. They are frequently coexisting and aggravating diseases. Both are chronic, noninfectious, and inflammatory conditions sharing to a certain extent important pathophysiologic similarities. Beneficial effects of probiotics are long known to mankind. Research is beginning to unravel the true nature of the human microbiome and its interaction with the immune system. The growing prevalence of atopic diseases in the developed world led to the proposition of the "hygiene hypothesis." Dysbiosis is linked to atopic diseases; probiotic supplementation is able to alter the microbiome and certain probiotic strains have immunomodulatory effects in favour of a suppression of Th-2 and stimulation of a Th1 profile. This review focuses on randomized, double-blind, placebo-controlled trials investigating clinical parameters in the treatment of chronic rhinitis and CRS. An emerging number of publications demonstrate beneficial effects using probiotics in clinical double-blind placebo-controlled (dbpc) trials in allergic rhinitis (AR). Using probiotics as complementary treatment options in AR seems to be a promising concept although the evidence is of a preliminary nature to date and more convincing trials are needed. There are no current data to support the use of probiotics in non-AR or CRS.

Correlation of three variables describing nasal patency (HD, MCA, NOSE score) in healthy subjects

Rhinoresistometry and acoustic rhinometry are two established apparative methods to objectify the respiratory function of the nose. Both methods use different variables to describe nasal patency: "hydraulic diameter", HD, in rhinoresistometry, and "minimal cross-sectional area", MCA1 (nasal isthmus) and MCA2 (head of the inferior turbinate and cavernous body of the nasal septum), in acoustic rhinometry.

OBJECTIVE

This study analyzes the mutual correlation of HD and MCA as a pilot study in patients without nasal pathologies. Additionally, we investigated if these objective variables correlate with the NOSE score, a validated tool to measure subjective perception of nasal patency.

METHOD

Planned data collection in a collective of 24 healthy subjects without nasal pathologies.

RESULTS

Statistically significant, weak to moderate correlations were found between HD and MCA2 before decongestion. A moderate correlation was found between both HD and MCA2 and the NOSE score on the narrower side.

CONCLUSION

In the assessment of nasal patency, it seems advisable to determine HD, MCA1 and MCA2, but also a subjective variable such as the NOSE score, which all seem to be not fully redundant variables. In further studies, the correlation of the variables should be assessed in patients with nasal pathologies.

Eosinophils and mast cells: a comparison of nasal mucosa histology and cytology to markers in nasal discharge in patients with chronic sino-nasal diseases

Allergic rhinitis (AR), nasal polyps (NP) as well as chronic rhinosinusitis (CRS) are all known to be associated with eosinophilic infiltration and elevated numbers of mast cells (MC) within the mucosa. Both cell types and their markers eosinophilic cationic protein (ECP) and tryptase are utilized in the diagnosis and management of chronic sino-nasal diseases. Mucosal cytology samples were gathered by cytobrush, histological samples were obtained from the inferior turbinate. In both sample sets, the number of eosinophils and MC was determined. Their corresponding markers ECP and tryptase were quantified from nasal discharge. Patients were grouped with reference to their main diagnosis: AR (n = 34), NP (n = 25), CRS (n = 27) and controls (n = 34). Eosinophil counts from cytobrush and ECP levels were significantly elevated in NP compared to all other groups-31- and 13-fold over control, respectively. However, histologic review did not reveal any difference in eosinophil count among groups. Tryptase was significantly elevated threefold in AR versus CRS and controls. No correlation to cytological and histological MC counts could be found. ECP levels in nasal discharge as well as eosinophil counts can provide useful information with regard to the diagnosis. Likewise, tryptase concentrations can do. The presented data show that the measurement of markers in nasal discharge is superior in differentiating among diagnosis groups. Given that the collection of nasal secretions is more comfortable for patients than the more invasive techniques, we recommend first line ECP and tryptase testing performed on nasal secretions.

IgE reactivity patterns in patients with allergic rhinoconjunctivitis to ragweed and mugwort pollens

BACKGROUND

Differential diagnosis between ragweed and mugwort pollen allergy represents a large clinical problem in areas where both plants are present. The aim of this study was to investigate ragweed- and mugwort-sensitized patients to identify specific IgE reactivity profiles. Results were correlated to clinical findings such as medical history and health-related quality of life (HRQL).

METHODS

Seventy-four patients with allergic rhinoconjunctivitis between July and October were examined and underwent in vivo tests (skin-prick test [SPT] and nasal provocation). Sera were evaluated for IgE reactivity to mugwort and ragweed pollen extracts, major (Art v 1; Amb a 1) and minor (profilin and calcium-binding protein) allergens. HRQL was evaluated using a standardized questionnaire.

RESULTS

Seventy-one patients revealed positive SPT reactivity against mugwort and 60 patients against ragweed extracts. Of these patients, 74 revealed IgE antibodies against mugwort extracts, whereas anti-Art v 1 antibodies were detectable in 50 individuals. Fifty-five patients showed IgE antibodies against natural ragweed extracts; anti-Amb v 1 antibodies were detected in six cases only. Using standardized clinical history and HRQL questionnaires we were not able to detect any differences within different reactivity patterns.

CONCLUSION

Within the investigated population of 74 weed-allergic patients the prevalence of true mugwort and ragweed sensitization can be calculated as 68 and 8%. High prevalence of ragweed sensitization when testing with full extracts can be explained by cross-reactivity between other weeds, e.g., mugwort rather than cosensitization. Differences in medical history and HRQL between different reactivity patterns were not detectable.

Enzymatic amplification of DNA by PCR: standard procedures and optimization

This unit describes a method for amplifying DNA enzymatically by the polymerase chain reaction (PCR), including procedures to quickly determine conditions for successful amplification of the sequence and primer sets of interest, and to optimize for specificity, sensitivity, and yield. Hot-start methods are described which can greatly improve specificity, sensitivity, and yield. This protocol suggests some relatively inexpensive methods to achieve hot start, and lists several commercial hot-start options which may be more convenient, but of course more expensive. The unit has recently been updated to include new information on reagents to enhance the reaction, better cycling parameters, and innovations in robotics and high-performance thermocyclers.

Olfactory dysfunction in seasonal and perennial allergic rhinitis

CONCLUSIONS

The limitation in olfactory function in patients with seasonal allergic rhinitis (AR) can be ascribed to an increase in eosinophilic and mast cell activity in the olfactory cleft. Therefore, the decrease in olfactory functions seems to be predominantly caused by the inflammation of the epithelium and not by the obstruction of the nose caused by the inflammation.

OBJECTIVE

Olfactory dysfunction is frequently seen in patients with AR; however, little is known about the underlying pathophysiological mechanisms. Therefore, the aim of the present study was to examine the olfactory function in patients with seasonal or perennial AR, and to correlate the results with data obtained by analysis of nasal secretion and obstruction.

METHODS

Olfactory function was tested using the Sniffin´Sticks test in patients with seasonal or perennial AR and in a control group. Nasal secretion analysis included eosinophilic cationic protein (ECP) and tryptase testing. Nasal obstruction was evaluated by rhinomanometry.

RESULTS

Patients with AR (seasonal and perennial) showed impaired olfactory functions in comparison with the control group. Nasal secretion analysis showed increased values of ECP and tryptase in the seasonal group in comparison with controls. Rhinomanometry showed no differences in nasal flow between the three groups.

Mediators and cytokines in persistent allergic rhinitis and nonallergic rhinitis with eosinophilia syndrome

BACKGROUND

Patients with nonallergic rhinitis with eosinophilia syndrome (NARES) show typical symptoms of persistent allergic rhinitis (PAR). The aim of the present study was to compare nasal cytokine patterns between NARES and PAR.

METHODS

Nasal secretions of 31 patients suffering from NARES, 20 patients with PAR to house dust mite and 21 healthy controls were collected using the cotton wool method and analyzed for interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) by Bio-Plex Cytokine Assay as well as eosinophil cationic protein (ECP) and tryptase by UniCAP-FEIA.

RESULTS

NARES and PAR presented elevated levels of tryptase, while ECP was markedly increased solely in NARES compared to both the controls and PAR. Elevated levels of IL-1β, IL-17, IFN-γ, TNF-α and MCP-1 were found in NARES compared to the controls as well as PAR. MIP-1β was elevated in NARES and PAR, while IL-4, IL-6 and G-CSF showed increased levels in NARES, and IL- 5 was elevated in PAR only.

CONCLUSIONS

In patients with NARES and PAR, eosinophils and mast cells appear to be the pivotal cells of inflammation, reflected by high levels of tryptase and ECP as well as IL-5 and GM-CSF as factors for eosinophil migration and survival. The elevated levels of proinflammatory cytokines in NARES may indicate the chronic, self-perpetuating process of inflammation in NARES which seems to be more pronounced than in PAR. IL-17 might be a factor for neutrophilic infiltration or be responsible for remodeling processes in NARES.

Sinonasal outcome under aspirin desensitization following functional endoscopic sinus surgery in patients with aspirin triad

Recalcitrant forms of recurrent nasal polyposis are problematic for patients as for rhinosurgeons. In aspirin-sensitive patients, aspirin desensitization is supposed to prevent recurrence by targeting the metabolism of arachidonic acid. Aspirin-sensitive patients (n = 65) following aspirin desensitization after functional endoscopic sinus surgery (FESS) for recurrent nasal polyposis under daily intake of 500-mg aspirin were compared to a post-FESS group (n = 81) of aspirin-sensitive individuals using exclusively topical mometasone. Quality of life (QoL) scores including sinonasal, pulmonal and general QoL items as well as endoscopic endonasal examination findings were evaluated during the postoperative follow-up period. After a follow-up period of minimum 18 months, a significant improvement in nasal obstruction, rhinorrhea, post nasal drip, sense of smell, facial pain, sleep quality and further general QoL items in desensitized patients was found compared to aspirin-sensitive controls. Improvement in sinonasal symptoms was evident, whereas the severity of asthmatic symptoms showed no significant changes. Although the pathophysiology of aspirin sensitivity is still not fully understood and the therapy is not sufficiently investigated, aspirin desensitization seems to have a positive effect on QoL scores concerning sinonasal symptoms and should be regarded as a possible postoperative treatment modality for recurrent nasal polyposis in aspirin-sensitive individuals.

Solitary chemosensory cells in the respiratory and vomeronasal epithelium of the human nose: a pilot study

BACKGROUND

Recently, solitary chemosensory cells have been described in the respiratory and vomeronasal epithelium of the rodent nose. Expressing G-protein coupled receptors for sweet, umami and bitter taste transduction, these cells are thought to mediate trigeminal reflexes upon stimulation with chemical irritants. The present study analyzes human nasal mucosa for the presence of solitary chemosensory cells.

METHODOLOGY

In human tissue samples from respiratory mucosa and the vomeronasal organ, gene expression of taste receptors families was studied in five patients using the Affymetrix Human Gene 1.0 ST Array and immunohistochemistry with specific antibodies.

RESULTS

Immunohistochemistry revealed that solitary chemosensory cells expressing G-protein coupled receptors for sweet, umami and bitter taste transduction are present in the human nose. cDNA microarray analysis congruently showed that cells expressing bitter taste receptors accumulate in the vomeronasal organ compared to the respiratory epithelium.

CONCLUSIONS

Solitary chemosensory cells expressing taste receptors are also present in the human nose. Since they are thought to mediate trigeminal reflexes, their role in the pathogenesis of nasal hyperreagibility should be elucidated in further studies.

Septal injection of botulinum neurotoxin A for idiopathic rhinitis: a pilot study

PURPOSE

Botulinum neurotoxin A (BTA) is a promising therapeutic option in the treatment of idiopathic rhinitis (IR), a disease characterized by nasal obstruction and hydrous rhinorrhea. The conventional localization for the injection of BTA in IR is the nasal turbinates. In our own clinical experience, submucoperichondrial injection of BTA in the nasal septum is an alternative that is easy to perform for the therapist and also well tolerated by the patient.

MATERIAL AND METHODS

Five patients received an injection of in total 80 mouse units Dysport (Ipsen Pharma, Ettlingen, Germany) in the nasal septum. The unpleasantness of the nasal injection of BTA was measured on a visual analogue scale. Over the course of 14 days, nasal symptoms (rhinorrhea, nasal obstruction, urge to sneeze, nasal pruritus), the number of facial tissues used daily, and possible complications were evaluated.

RESULTS

The unpleasantness of the injection of BTA into the nasal septum after local anesthesia was rated low (visual analogue scale, 0.76 on average). A good subjective symptom control was achieved in 3 patients concerning rhinorrhea and in all patients concerning nasal obstruction. The number of facial tissues used daily as a parameter for rhinorrhea was on average 21.0 before the injection of BTA, decreased in 4 patients over the course of time, and was on average 5.8 after 14 days. No patient reported any adverse effects after the injection of BTA.

CONCLUSIONS

This pilot study demonstrates that septal injection of BTA in patients with IR can achieve good symptom control and patient comfort and should be compared in further studies to the conventional turbinal injection technique.

Solitary chemosensory cells in the respiratory and vomeronasal epithelium of the human nose: a pilot study

BACKGROUND

Recently, solitary chemosensory cells have been described in the respiratory and vomeronasal epithelium of the rodent nose. Expressing G-protein coupled receptors for sweet, umami and bitter taste transduction, these cells are thought to mediate trigeminal reflexes upon stimulation with chemical irritants. The present study analyzes human nasal mucosa for the presence of solitary chemosensory cells.

METHODOLOGY

In human tissue samples from respiratory mucosa and the vomeronasal organ, gene expression of taste receptors families was studied in five patients using the Affymetrix Human Gene 1.0 ST Array and immunohistochemistry with specific antibodies.

RESULTS

Immunohistochemistry revealed that solitary chemosensory cells expressing G-protein coupled receptors for sweet, umami and bitter taste transduction are present in the human nose. cDNA microarray analysis congruently showed that cells expressing bitter taste receptors accumulate in the vomeronasal organ compared to the respiratory epithelium.

CONCLUSIONS

Solitary chemosensory cells expressing taste receptors are also present in the human nose. Since they are thought to mediate trigeminal reflexes, their role in the pathogenesis of nasal hyperreagibility should be elucidated in further studies.

Recombinant marker allergens in diagnosis of patients with allergic rhinoconjunctivitis to tree and grass pollens

BACKGROUND

The aim of this study was to investigate recombinant marker allergens in patients with allergic rhinoconjunctivitis to tree and grass pollens.

METHODS

Sera of 260 tree pollen- and 282 grass pollen-allergic patients were analyzed. Bet v 1 and Phl p 1/p 5 were used as marker allergens for allergies to pollen from birch and grasses. Profilin (Bet v 2 and Phl p 12) and calcium-binding protein (Bet v 4 and Phl p 7) were used as markers for polysensitization.

RESULTS

Two hundred thirty-nine (92%) patients tested positive for IgE anti-Bet v 1. All of them were positive for IgE antibodies against natural birch extract (t3), hazel (t4), and alder (t2). Bet v 1 in combination with t3 identified allergies from related trees with a sensitivity of 99.2%. Two hundred fifty-six patients (91%) tested positive for IgE anti-Phl p 1 and/or anti-Phl p 5. All of them were positive for IgE antibodies against natural timothy (g6) and rye (g12) extract. Phl p 1/p 5 and natural timothy extract identified allergies from grasses and rye with a sensitivity of 99.3%. All Patients reacting to the cross-reactive allergens Bet v 2, Phl p 12, Bet v 4, and Phl p 7 were polysensitized.

CONCLUSION

Bet v 1 in combination with natural birch pollen extract identifies allergies from related trees with a sensitivity of 99.2%. Phl p 1, Phl p 5, and natural timothy extract identifies allergies from grasses and rye in 99.3%. Reactivity to the allergens Bet v 2, Phl p 12, Bet v 4, and Phl p 7 identifies polysensitization and cross-reactivity.