Allergen immunotherapy (AIT) has gained a permanent place in the therapeutic arsenal for the patient with allergy. Particularly, substantial evidence has been established for the efficacy of AIT in allergic rhinitis. A hallmark of AIT is it disease modifying effect resulting in persistent benefit after the treatment has been terminated. Both the subcutaneous and sublingual mode of administration appear to be safe. It is, however, a matter of debate whether AIT can be implemented for patients with asthma. EAACI and GINA guidelines recommend sublingual AIT in house dust mite driven asthma. The question however remains whether the different available forms of AIT should be used for allergic asthma in general.
Background: The administration of L-glutamine (Gln) suppresses allergic airway inflammation via the rapid upregulation of MAPK phosphatase (MKP)-1, which functions as a negative regulator of inflammation by deactivating p38 and JNK mitogen-activated protein kinases (MAPKs). However, the role of endogenous Gln remains to be elucidated. Therefore, we investigated the mechanism by which endogenous Gln regulates MKP-1 induction and allergic airway inflammation in an ovalbumin-based murine asthma model. Methods: We depleted endogenous Gln levels using l-γ-glutamyl- p-nitroanilide (GPNA), an inhibitor of the Gln transporter ASCT2, and glutamine synthetase small interfering (si)RNA. Lentivirus expressing MKP-1 was injected to achieve overexpression of MKP-1. Asthmatic phenotypes were assessed using our previously developed ovalbumin-based murine model, which is suitable for examining sequential asthmatic events, including neutrophil infiltration. Gln levels were analyzed using a Gln assay kit. Results: GPNA or glutamine synthetase siRNA successfully depleted endogenous Gln levels. Importantly, homeostatic MKP-1 induction did not occur at all, which resulted in prolonged p38 MAPK and cytosolic phospholipase A 2 (cPLA 2) phosphorylation in Gln-deficient mice. Gln deficiency augmented all examined asthmatic reactions, but it exhibited a strong bias toward increasing the neutrophil count, which was not observed in MKP-1-overexpressing lungs. This neutrophilia was inhibited by a cPLA 2 inhibitor and a leukotriene B4 inhibitor, but not by dexamethasone. Conclusion: Gln deficiency leads to the impairment of MKP-1 induction and activation of p38 MAPK and cPLA 2, resulting in the augmentation of neutrophilic, more so than eosinophilic, airway inflammation.
SARS-CoV-2 caused one of the most devastating pandemics in the recent history of mankind. Due to various countermeasures, including lock-downs, wearing masks and increased hygiene, the virus has been controlled in some parts of the world. More recently, the availability of vaccines, based on RNA or Adenoviruses, have greatly added to our ability to keep the virus at bay, again in some parts of the world only. While available vaccines are effective, it would be desirable to also have more classical vaccines at hand for the future. Key feature of vaccines for long-term control of SARS-CoV-2 would be inexpensive production at large scale, ability to make multiple booster injections and long-term stability at +4 oC. Here we describe such a vaccine candidate, consisting of the SARS-CoV-2 receptor binding motif grafted genetically onto the surface of the immunologically optimized cucumber mosaic virus, called CuMV TT-RBM. Using bacterial fermenter production and continuous flow centrifugation, the productivity of the production process is estimated to be >2.5 million doses per 1000 liter fermenter run and the vaccine candidate is stable for at least 14 months at 4°C. We further demonstrate that the candidate vaccine is highly immunogenic in mice and rabbits and induces more high avidity antibodies compared to convalescent human sera and antibodies induced are more cross-reactive to mutant RBDs for variants of concern (VoC). Furthermore, antibody responses are neutralizing and long-lived. This, the here presented VLP-based vaccine may be a good candidate for use as conventional vaccine in the long-term.
COVID-19 vaccination with BNT162b2 and ChAdOx1 vaccines induces nasal neutralizing antibodiesDeclercq Jozefien(1,2,5)*, Tobback Els(3)*, Vanhee Stijn(2,5), Natalie De Ruyck(1), Gerlo Sarah(4), Gevaert Philippe(1)**, Vandekerckhove Linos(3,4)***shared co-first authorship** shared last authorshipUpper Airways Research Lab URL, Department of Otorhinolaryngology, Ghent University, Ghent, BelgiumLaboratory of immunoregulation, VIB Center for Inflammation Research, Ghent, BelgiumDepartment of General Internal Medicine, Ghent University Hospital, Ghent, BelgiumHIV Cure Research Centre, Department of Internal Medicine and Pediatrics, Ghent University, Ghent, BelgiumDepartment of Internal Medicine and Pediatrics, Ghent University, Ghent, BelgiumCorresponding author:Prof. Dr. Philippe GevaertUpper Airways Research Lab URL, Department of Otorhinolaryngology, Ghent University,C Heymanslaan 10, 1P1Ghent, Belgium+3293324922Philippe.firstname.lastname@example.orgFinancial support: no fundingWord count: 591
Background Vaccines that incorporate multiple SARS-CoV-2 antigens can further broaden the breadth of virus-specific cellular and humoral immunity. This study describes the development and immunogenicity of SARS-CoV-2 VLP vaccine that incorporates the 4 structural proteins of SARS-CoV-2. Methods VLPs were generated in transiently transfected HEK293 cells, purified by multimodal chromatography and characterized by tunable resistive pulse sensing, AFM, SEM, and TEM. Immunoblotting studies verified the protein identities of VLPs. Cellular and humoral immune responses of immunized animals demonstrated the immune potency of the formulated VLP vaccine. Results Transiently transfected HEK293 cells reproducibly generated vesicular VLPs that were similar in size to and expressing all four structural proteins of SARS-CoV-2. Alum adsorbed, K3-CpG ODN adjuvanted VLPs elicited high titer anti-S, anti-RBD, anti-N IgG, triggered multifunctional Th1 biased T cell responses, reduced virus load and prevented lung pathology upon live virus challenge in vaccinated animals. Conclusion These data suggest that VLPs expressing all four structural protein antigens of SARS-CoV-2 are immunogenic and can protect animals from developing COVID-19 infection following vaccination.
Background: Early exposure to allergens through a defect skin barrier has been proposed as a mechanism for inducing sensitization and development of allergic diseases. We hypothesized that early-onset, severe atopic dermatitis (AD) is associated with development of aeroallergen sensitization and allergic rhinitis. Methods: We included 368 children from the Copenhagen Prospective Studies on Asthma in Childhood 2000 (COPSAC 2000) at-risk mother-child cohort. AD was diagnosed prospectively based on Hanifin&Rajka’s criteria and severity assessed using the Scoring Atopic Dermatitis (SCORAD) index. Early-onset AD was defined as debut ≤1 year, late-onset as debut from 1-6 years. Aeroallergen sensitization and allergic rhinitis were diagnosed at ages 6-7 and 12 years. Associations between early-onset and late-onset AD and allergy endpoints were calculated using general estimating equations (GEE) models to compute the overall odds ratios (OR) for both time points. Results: Early-onset AD (yes/no) and severity (SCORAD) were associated with development of aeroallergen sensitization during childhood; GEE OR=1.68 [1.08; 2.62], p=0.02 and 1.08 [1.03; 1.12], p<0.001, whereas late-onset was not; GEE OR=1.65 [0.92; 2.94], p=0.08 and 1.01 [0.97; 1.06], p=0.55. The same trend was seen for allergic rhinitis with significant association between early-onset AD and allergic rhinitis; GEE OR=1.56 [1.01; 2.41], p=0.04 and severity; GEE OR=1.09 [1.05; 1.13], p<0.001, whereas late-onset AD showed no association. The effects on sensitization and rhinitis of early-onset vs. late-onset AD severity were significantly different: p-interaction sensitization=0.03 and p-interaction rhinitis<0.01. Conclusion: Increasing severity of early-onset AD, but not late-onset AD, associates with aeroallergen sensitization and allergic rhinitis later in childhood.
Role of activation of the coagulation system in the pathogenesis of urticariaTaro Yasuma,1 Corina N. D’Alessandro-Gabazza,1 Tetsu Kobayashi,2 John Morser,3 Esteban C Gabazza.1*1Department of Immunology,2Department of Pulmonary and Critical Care Medicine, Mie University Faculty and Graduate School of Medicine, and Mie University Hospital, Edobashi 2-174, Tsu, Mie 514-8507, Japan.3Division of Hematology, Stanford University School of Medicine, 291 Campus Drive, Stanford, CA 94305, United States*Correspondence: Esteban C Gabazza, MD, PhD, Department of Immunology, Mie University Graduate School of Medicine, Edobashi 2-174, Postal Code 514-8507, Tsu-city, Mie, Japan. Tel.: +81 59 231 5017; fax: +81 59 231 5225.E-mail:email@example.comWord count: 590
Background The same dosing schedule, 1000 SQ-U times three, with one-month intervals, have been evaluated in most trials of intralymphatic immunotherapy (ILIT) for the treatment of allergic rhinitis (AR). The present studies evaluated if a dose escalation in ILIT can enhance the clinical and immunological effects, without compromising safety. Methods Two randomized double-blind placebo-controlled trials of ILIT for grass pollen induced AR were performed. The first included 29 patients that had recently ended 3 years of SCIT and the second contained 39 not previously vaccinated patients. An up-dosage of 1000-3000-10 000 (5000 + 5000 with 30 minutes apart) SQ-U with one month in between was evaluated. Results Doses up to 10 000 SQ-U was safe after recent SCIT. The combined symptom-medication scores (CSMS) were reduced by 31% and the grass specific IgG4 levels in blood were doubled. In ILIT de novo, the two first patients that received active treatment developed serious adverse reactions at 5000 SQ-U. A modified up-dosing schedule; 1000-3000-3000 SQ-U appeared to be safe but failed to improve the CSMS. Flow cytometry analyses showed increased activation of lymph node derived dendritic but not T-cells. Quality of life and nasal provocation response did not improve in any study. Conclusion ILIT in high doses after SCIT appears to further reduce grass pollen induced seasonal symptoms and may be considered as an add-on treatment for patients that do not reach full symptom control after SCIT. Up-dosing schedules de novo with three monthly injections that exceeds 3 000 SQ-U should be avoided.
Food Allergy (FA) is now one of the most common chronic diseases of childhood often lasting throughout life and leading to significant worldwide healthcare burden. The precise mechanisms responsible for the development of this inflammatory condition are largely unknown; however, a multifactorial aetiology involving both environmental and genetic contributions is well accepted. A precise understanding of the pathogenesis of FA is an essential first step to developing comprehensive prevention strategies that could mitigate this epidemic. As it is frequently preceded by atopic dermatitis and can be prevented by early antigen introduction, the development of FA is likely facilitated by the improper initial presentation of antigen to the developing immune system. Primary oral exposure of antigens allowing for presentation via a well-developed mucosal immune system, rather than through a disrupted skin epidermal barrier, is essential to prevent FA. In this review, we present the data supporting the necessity of 1) an intact epidermal barrier to prevent epicutaneous antigen presentation, 2) the presence of specific commensal bacteria to maintain an intact mucosal immune system and 3) maternal/infant diet diversity, including vitamins and minerals, and appropriately timed allergenic food introduction to prevent FA.
Title: Notch4, uncovering an immunomodulator in allergic asthmaAuthors: Beatriz Moyaa,b, Manali Mukherjeec and Parameswaran Nairca. Department of Allergy, Hospital Universitario 12 de Octubre, Madrid, Spainb. Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, Spainc. Division of Respirology, Department of Medicine, McMaster University, Hamilton & Firestone Institute for Respiratory Health, St Joseph’s Healthcare, Hamilton, ON, CanadaCorrespondence to : Beatriz Moya. Allergy Department. Hospital Universitario 12 de Octubre, Madrid, SpainEmail:firstname.lastname@example.orgAcknowledgements : Dr. Mukherjee is supported by investigator award from Canadian Institutes of Health Research and Canadian Allergy, Asthma, and Immunology Foundation. She has received honorarium from AZ, GSK and her university has received grants from Methapharm Speciality Pharmaceuticals. Dr. Nair is supported by the Frederick E. Hargreave Teva Innovation Chair in Airway Diseases. He has received honoraria from AZ, Sanofi, Teva, Merck, Novartis and Equillium and his university has received research grants from AZ, Teva, Sanofi, Novartis, BI and Methapharm. The authors recognize Dr. Anna Globinska for graphical abstract design and Dr. Rodrigo Jiménez-Saiz for critical review of the manuscript.Keywords: Allergic asthma; Airway inflammation; Th2 cell; Th17 cell; Treg cell; Notch4 receptorAbbreviations: Th, T helper; UFPs, pollutant ultrafine particles; AMs, alveolar macrophages; Treg cells, regulatory T cells; ILC2s, type 2 innate lymphoid cells; GDF15, cytokine growth and differentiation factor 15; IL, interleukin; IL-6R, interleukin-6 receptor; IL-4R, interleukin-4 receptorWord count: 918/1000
Methods: Twenty-two French nursing homes were included. COVID-19 had been diagnosed with real-time reverse-transcriptase polymerase chain reaction (RT-PCR) for SARS-CoV-2. Blood S-protein IgG and nucleocapsid (N) IgG protein (N-protein IgG) were measured 21-24 days after the first jab (1,004 residents) and 6 weeks after the second (820 residents). Results: Among the 735 residents without prior COVID-19, 41.7% remained seronegative for S-protein IgG after the first jab vs 2.1% of the 270 residents with a previous positive RT-PCR (p<0.001). After the second jab, only 3% of the 586 residents without prior COVID-19 remained seronegative. However, 26.5% of them had low S-protein IgG levels (50-1050 UA/mL) vs 6.4% of the 222 residents with prior COVID-19. Residents with old infection (first wave), or seropositive for N-protein IgG at the time of vaccination, had the highest S-protein IgG levels. Residents with a prior COVID-19 infection had higher S-protein IgG levels after one dose than those without two jabs. Interpretation: A single vaccine jab is sufficient to reach immunity in residents with prior COVID-19. Most residents without prior COVID-19 are seropositive for S-protein IgG after the second jab, but around 30% have low levels of S-protein IgG. Whether residents with no or low post-vaccine immunity are at higher risk of symptomatic COVID-19 requires further analysis.
Background: Several new variants of SARS-CoV-2 have emerged since fall 2020 which have multiple mutations in the receptor binding domain (RBD) of the spike protein. It is unclear which mutations affect receptor affinity versus immune recognition. Methods: We produced RBD with single mutations (E484K, K417N or N501Y) or with all three mutations combined and tested their binding to ACE2 by biolayer interferometry (BLI). The ability of convalescent sera to recognize RBDs and block their interaction with ACE2 was tested as well. Results: We demonstrated that single mutation N501Y increased binding affinity to ACE2 but did not significantly affect its recognition by convalescent sera. In contrast, single mutation E484K had almost no impact on the binding kinetics, but essentially abolished recognition of RBD by convalescent sera. Interestingly, combining mutations E484K, K417N and N501Y resulted in a RBD with both features: enhanced receptor binding and abolished immune recognition. Conclusion: Our data demonstrate that single mutations either affect receptor affinity or immune recognition while triple mutant RBDs combine both features.