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Proteínas Portadoras , Síndrome de Kounis , Humanos , Adolescente , Síndrome de Kounis/diagnóstico , Síndrome de Kounis/etiología , Proteínas Portadoras/efectos adversos , Proteínas Portadoras/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/inmunología , Femenino , Masculino , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunologíaRESUMEN
BACKGROUND: Cross-reactivity between nonspecific lipid transfer proteins could cause anaphylaxis, further influencing food avoidance and nutrient deficiencies. The one affecting olive pollen (Ole e 7) and peach (Pru p 3) may underlie a variety of pollen-food syndromes, though a deep molecular analysis is necessary. METHODS: Three Ole e 7-monosensitised patients (MON_OLE), three Pru p 3-monosensitised patients (MON_PRU) and three bisensitised patients (BI) were selected. For epitope mapping, both digested proteins were incubated with patient sera, and the captured IgE-bound peptides were characterised by LC-MS. RESULTS: The analysis revealed two Ole e 7 epitopes and the three Pru p 3 epitopes previously described. Interestingly, the "KSALALVGNKV" Ole e 7 peptide was recognised by MON_OLE, BI and MON_PRU patients. Conversely, all patients recognised the "ISASTNCATVK" Pru p 3 peptide. Although complete sequence alignment between both proteins revealed 32.6% identity, local alignment considering seven residue fragments showed 50 and 57% identity when comparing "ISASTNCATVK" with Ole e 7 and "KSALALVGNKV" with Pru p 3. CONCLUSIONS: This study mapped sIgE-Ole e 7-binding epitopes, paving the way for more precise diagnostic tools. Assuming non-significant sequence similarity, structural homology and shared key residues may underlie the potential cross-reactivity between Ole e 7 and Pru p 3 nsLTPs.
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Antígenos de Plantas , Reacciones Cruzadas , Hipersensibilidad a los Alimentos , Inmunoglobulina E , Olea , Proteínas de Plantas , Polen , Prunus persica , Humanos , Antígenos de Plantas/inmunología , Hipersensibilidad a los Alimentos/inmunología , Polen/inmunología , Inmunoglobulina E/inmunología , Inmunoglobulina E/sangre , Olea/inmunología , Proteínas de Plantas/inmunología , Femenino , Masculino , Prunus persica/inmunología , Mapeo Epitopo , Adulto , Rinitis Alérgica Estacional/inmunología , Secuencia de Aminoácidos , Epítopos/inmunología , Alérgenos/inmunología , Persona de Mediana Edad , Proteínas Portadoras/inmunologíaRESUMEN
BACKGROUND: Group A Streptococcus (Strep A) causes both uncomplicated and severe invasive infections, as well as the post-infection complications acute rheumatic fever and rheumatic heart disease. Despite the high global burden of disease resulting from Strep A infections, there is not a licensed vaccine. A 30-valent M protein-based vaccine has previously been shown to be immunogenic in animal models and in a Phase I clinical trial (NCT02564237). Here, we assessed the immunogenicity of a 30-valent messenger (m)RNA vaccine designed to express the same M peptide targets as the 30-valent protein vaccine and compared it with the protein vaccine. METHODS: Female New Zealand white rabbits were immunized with one of four vaccine formulations (3 doses of each formulation at days 1, 28, and 56): soluble mRNA (100 µg/animal), C-terminal transmembrane mRNA (100 µg/animal), protein vaccine (400 µg/animal), or a non-translatable RNA control (100 µg/animal). Serum was collected one day prior to the first dose and on days 42 and 70. Rabbit serum samples were assayed for antibody levels against synthetic M peptides by ELISA. HL-60 opsonophagocytic killing (OPK) assays were performed to assess functional antibody levels. RESULTS: Serum IgG levels were similar for the mRNA and protein vaccines. The CtTM version of the mRNA vaccine elicited slightly higher antibody levels than the mRNA designed to express soluble proteins. OPK activity was similar for the mRNA and protein vaccines, regardless of M type. CONCLUSIONS: The total antibody responses and functional antibody levels elicited by the 30-valent mRNA Strep A vaccines were similar to those observed following immunization with the analogous protein vaccine. The mRNA vaccine platform provides potential advantages to protein-based vaccines including inherent adjuvant activity, increased production efficiency, lower cost, and the potential to rapidly change epitopes/peptides, all of which are important considerations related to multivalent Strep A vaccine development.
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Anticuerpos Antibacterianos , Antígenos Bacterianos , Infecciones Estreptocócicas , Vacunas Estreptocócicas , Streptococcus pyogenes , Animales , Conejos , Femenino , Vacunas Estreptocócicas/inmunología , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/genética , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/inmunología , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/genética , Streptococcus pyogenes/inmunología , Streptococcus pyogenes/genética , Inmunogenicidad Vacunal , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Portadoras/inmunología , Proteínas Portadoras/genética , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , ARN Mensajero/genética , ARN Mensajero/inmunologíaRESUMEN
The intrinsically disordered polyglutamine-binding protein 1 (PQBP1) has been linked to various cellular processes including transcription, alternative splicing, translation and innate immunity. Mutations in PQBP1 are causative for neurodevelopmental conditions collectively termed as the Renpenning syndrome spectrum. Intriguingly, cells of Renpenning syndrome patients exhibit a reduced innate immune response against human immunodeficiency virus 1 (HIV-1). PQBP1 is responsible for the initiation of a two-step recognition process of HIV-1 reverse-transcribed DNA products, ensuring a type 1 interferon response. Recent investigations revealed that PQBP1 also binds to the p17 protein of avian reovirus (ARV) and is affected by the ORF52 of Kaposi's sarcoma-associated herpesvirus (KSHV), possibly also playing a role in the innate immune response towards these RNA- and DNA-viruses. Moreover, PQBP1-mediated microglia activation in the context of tauopathies has been reported, highlighting the role of PQBP1 in sensing exogenous pathogenic species and innate immune response in the central nervous system. Its unstructured nature, the promiscuous binding of various proteins and its presence in various tissues indicate the versatile roles of PQBP1 in cellular regulation. Here, we systematically review the available data on the structure of PQBP1 and its cellular functions and interactome, as well as possible implications for innate immune responses and neurodegenerative disorders.
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Inmunidad Innata , Humanos , Animales , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/inmunología , Unión Proteica , Proteínas Portadoras/metabolismo , Proteínas Portadoras/inmunología , Proteínas Portadoras/genética , VIH-1/inmunología , VIH-1/genética , Interacciones Huésped-Patógeno/inmunologíaRESUMEN
Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is a leading blood-stage malaria vaccine antigen target, currently in a phase 2b clinical trial as a full-length soluble protein/adjuvant vaccine candidate called RH5.1/Matrix-M. We identify that disordered regions of the full-length RH5 molecule induce non-growth inhibitory antibodies in human vaccinees and that a re-engineered and stabilized immunogen (including just the alpha-helical core of RH5) induces a qualitatively superior growth inhibitory antibody response in rats vaccinated with this protein formulated in Matrix-M adjuvant. In parallel, bioconjugation of this immunogen, termed "RH5.2," to hepatitis B surface antigen virus-like particles (VLPs) using the "plug-and-display" SpyTag-SpyCatcher platform technology also enables superior quantitative antibody immunogenicity over soluble protein/adjuvant in vaccinated mice and rats. These studies identify a blood-stage malaria vaccine candidate that may improve upon the current leading soluble protein vaccine candidate RH5.1/Matrix-M. The RH5.2-VLP/Matrix-M vaccine candidate is now under evaluation in phase 1a/b clinical trials.
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Anticuerpos Antiprotozoarios , Vacunas contra la Malaria , Plasmodium falciparum , Proteínas Protozoarias , Vacunas de Partículas Similares a Virus , Animales , Vacunas contra la Malaria/inmunología , Anticuerpos Antiprotozoarios/inmunología , Plasmodium falciparum/inmunología , Vacunas de Partículas Similares a Virus/inmunología , Humanos , Ratones , Proteínas Protozoarias/inmunología , Ratas , Malaria Falciparum/prevención & control , Malaria Falciparum/inmunología , Antígenos de Protozoos/inmunología , Femenino , Proteínas Portadoras/inmunología , Ratones Endogámicos BALB CRESUMEN
The highly conserved and essential Plasmodium falciparum reticulocyte-binding protein homolog 5 (PfRH5) has emerged as the leading target for vaccines against the disease-causing blood stage of malaria. However, the features of the human vaccine-induced antibody response that confer highly potent inhibition of malaria parasite invasion into red blood cells are not well defined. Here, we characterize 236 human IgG monoclonal antibodies, derived from 15 donors, induced by the most advanced PfRH5 vaccine. We define the antigenic landscape of this molecule and establish that epitope specificity, antibody association rate, and intra-PfRH5 antibody interactions are key determinants of functional anti-parasitic potency. In addition, we identify a germline IgG gene combination that results in an exceptionally potent class of antibody and demonstrate its prophylactic potential to protect against P. falciparum parasite challenge in vivo. This comprehensive dataset provides a framework to guide rational design of next-generation vaccines and prophylactic antibodies to protect against blood-stage malaria.
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Anticuerpos Monoclonales , Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Inmunoglobulina G , Vacunas contra la Malaria , Malaria Falciparum , Plasmodium falciparum , Proteínas Protozoarias , Animales , Humanos , Ratones , Anticuerpos Monoclonales/inmunología , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/inmunología , Proteínas Portadoras/inmunología , Epítopos/inmunología , Eritrocitos/parasitología , Eritrocitos/inmunología , Inmunoglobulina G/inmunología , Vacunas contra la Malaria/inmunología , Malaria Falciparum/inmunología , Malaria Falciparum/prevención & control , Malaria Falciparum/parasitología , Plasmodium falciparum/inmunología , Proteínas Protozoarias/inmunologíaRESUMEN
Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is the most advanced blood-stage malaria vaccine candidate and is being evaluated for efficacy in endemic regions, emphasizing the need to study the underlying antibody response to RH5 during natural infection, which could augment or counteract responses to vaccination. Here, we found that RH5-reactive B cells were rare, and circulating immunoglobulin G (IgG) responses to RH5 were short-lived in malaria-exposed Malian individuals, despite repeated infections over multiple years. RH5-specific monoclonal antibodies isolated from eight malaria-exposed individuals mostly targeted non-neutralizing epitopes, in contrast to antibodies isolated from five RH5-vaccinated, malaria-naive UK individuals. However, MAD8-151 and MAD8-502, isolated from two malaria-exposed Malian individuals, were among the most potent neutralizers out of 186 antibodies from both cohorts and targeted the same epitopes as the most potent vaccine-induced antibodies. These results suggest that natural malaria infection may boost RH5-vaccine-induced responses and provide a clear strategy for the development of next-generation RH5 vaccines.
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Anticuerpos Neutralizantes , Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Vacunas contra la Malaria , Malaria Falciparum , Plasmodium falciparum , Humanos , Anticuerpos Neutralizantes/inmunología , Plasmodium falciparum/inmunología , Malaria Falciparum/inmunología , Malaria Falciparum/prevención & control , Malaria Falciparum/parasitología , Vacunas contra la Malaria/inmunología , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/inmunología , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Proteínas Protozoarias/inmunología , Anticuerpos Monoclonales/inmunología , Adulto , Linfocitos B/inmunología , Epítopos/inmunología , Femenino , Malí , Proteínas Portadoras/inmunología , Masculino , AdolescenteRESUMEN
PURPOSE OF REVIEW: To provide an update on the diagnosis of non-specific Lipid Transfer Protein (nsLTP) allergy. RECENT FINDINGS: More publications report the presence of nsLTP allergy in Northern European countries and nsLTP sensitisation in children. Individuals are more likely to have severe reactions if there is recognition of increasing numbers of LTP components. Diagnosis is problematic; not all those with nsLTP allergy will have a positive test to a peach extract containing Pru p 3, the peach nsLTP. Sensitisation to nsLTP is being reported in more countries, including to the nsLTP in Cannabis Sativa in North America. Meals containing multiple nsLTP foods are more likely to be involved in co-factor reactions. Component-resolved diagnostics are superior to skin prick tests, to determine sensitisation to the individual nsLTP allergens causing symptoms and, in the future, the Basophil Activation test may best discriminate between sensitization and clinical allergy.
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Antígenos de Plantas , Proteínas Portadoras , Hipersensibilidad a los Alimentos , Pruebas Cutáneas , Humanos , Proteínas Portadoras/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/inmunología , Antígenos de Plantas/inmunología , Alérgenos/inmunología , Proteínas de Plantas/inmunología , Niño , Inmunoglobulina E/inmunología , Inmunoglobulina E/sangreRESUMEN
BACKGROUND: Allergy to peanuts and tree nuts is a common cause of food allergy in Spain, with lipid transfer proteins (LTP) being the most frequently recognized panallergen. LTP sensitization often leads to multiple food group sensitivities, resulting in overly restrictive diets that hinder patient's quality of life. This study aimed to assess the tolerance of peanuts and tree nuts (hazelnuts and walnuts) in children sensitized to LTP, potentially mitigating the need for such diets. METHODS: This prospective study enrolled individuals diagnosed with allergy to peanuts, hazelnuts, or walnuts. Data were collected from medical records, including demographics and clinical history. Allergological assessment comprised skin prick tests using commercial extracts and the nuts in question, alongside measurements of total and specific IgE to nuts and their primary molecular components. Participants showing positive LTP sensitization without sensitization to seed storage proteins underwent open oral nut challenges. RESULTS: A total of 75 individuals labeled as allergic to peanuts, 44 to hazelnuts, and 51 to walnuts were included. All of them underwent an open oral provocation test with the incriminated nut, showing a high tolerance rate. Peanut was tolerated by 98.6% of patients, 97.72% tolerated hazelnut, and 84.3% tolerated walnut. CONCLUSION: The findings suggest that the majority of patients allergic to peanuts, hazelnuts, or walnuts, due to LTP sensitization and lacking IgE reactivity to seed storage proteins, can tolerate these nuts. This supports the need for personalized nut tolerance assessments to avoid unnecessary dietary restrictions.
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Arachis , Proteínas Portadoras , Tolerancia Inmunológica , Inmunoglobulina E , Hipersensibilidad a la Nuez , Pruebas Cutáneas , Humanos , Masculino , Femenino , Proteínas Portadoras/inmunología , Niño , España , Estudios Prospectivos , Preescolar , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Hipersensibilidad a la Nuez/inmunología , Hipersensibilidad a la Nuez/diagnóstico , Arachis/inmunología , Hipersensibilidad al Cacahuete/inmunología , Hipersensibilidad al Cacahuete/diagnóstico , Alérgenos/inmunología , Juglans/inmunología , Nueces/inmunología , Adolescente , Corylus/inmunología , Hipersensibilidad a Nueces y Cacahuetes/inmunología , Antígenos de Plantas/inmunologíaRESUMEN
BACKGROUND: Allergy to lipid transfer proteins (LPT) is common in Mediterranean Europe, and it causes severe reactions in patients and affects multiple foods, impairing the quality of life. OBJECTIVE: This study aimed to describe the clinical and sensitization profile of patients with LTP syndrome and to determine a clinical pattern of severity. Molecular diagnosis is shown in a broad population through microarrays. MATERIAL AND METHODS: This study was performed at the LTP Allergy Consultation of the Reina Sofia Hospital in Murcia, Spain. We analyzed the patients' characteristics, reactions, cofactors, food implicated, quality of life, skin prick test to food and aeroallergens, and serologic parameters, such as total immunoglobulin E, peach LTP (Pru p 3 IgE) and immunoglobulin G4, and microarray Immuno Solid-phase Allergen Chip (ISAC). We related the severity of the reactions with other variables. RESULTS: We presented a series of 236 patients diagnosed with LTP allergy, 54.66% suffering from anaphylaxis, 36.02% from urticaria angioedema, and 9.32% from oral allergy syndrome. The most frequently implicated food was peach, producing symptoms in 70% of patients, followed by walnut in 55%, peanut in 45%, hazelnut in 44%, and apple in 38% patients. Regarding the food that provoked anaphylaxis, walnut was the most frequent instigator, along with peach, peanut, hazelnut, almond, sunflower seed, and apple. According to the severity of LPT reaction, we did not discover significant differences in gender, age, food group involved, and serologic parameters. We found differences in the presence of cofactors, with 48.84% of cofactors in patients with anaphylaxis, compared to 27.1% in patients without anaphylaxis and in family allergy background (P < 0.0001). CONCLUSION: In our series of patients, 54% presented anaphylaxis, and the foods that most frequently produced symptoms were peaches, apples, and nuts. Cofactors and family allergy backgrounds were associated with the severity of LPT reaction.
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Alérgenos , Antígenos de Plantas , Hipersensibilidad a los Alimentos , Inmunoglobulina E , Pruebas Cutáneas , Humanos , Masculino , Femenino , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Adulto , Persona de Mediana Edad , Antígenos de Plantas/inmunología , Alérgenos/inmunología , España/epidemiología , Adolescente , Proteínas de Plantas/inmunología , Adulto Joven , Proteínas Portadoras/inmunología , Niño , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Anciano , Calidad de Vida , Anafilaxia/inmunología , Anafilaxia/diagnóstico , Anafilaxia/etiología , PreescolarRESUMEN
Pollen from common ragweed is an important allergen source worldwide and especially in western and southern Romania. More than 100 million patients suffer from symptoms of respiratory allergy (e.g., rhinitis, asthma) to ragweed pollen. Among the eleven characterized allergens, Amb a 6 is a non-specific lipid transfer protein (nsLTP). nsLTPs are structurally stable proteins in pollen and food from different unrelated plants capable of inducing severe reactions. The goal of this study was to produce Amb a 6 as a recombinant and structurally folded protein (rAmb a 6) and to characterize its physicochemical and immunological features. rAmb a 6 was expressed in Spodoptera frugiperda Sf9 cells as a secreted protein and characterized by mass spectrometry and circular dichroism (CD) spectroscopy regarding molecular mass and fold, respectively. The IgE-binding frequency towards the purified protein was evaluated using sera from 150 clinically well-characterized ragweed-allergic patients. The allergenic activities of rAmb a 6 and the nsLTP from the weed Parietaria judaica (Par j 2) were evaluated in basophil activation assays. rAmb a 6-specific IgE reactivity was associated with clinical features. Pure rAmb a 6 was obtained by insect cell expression. Its deduced molecular weight corresponded to that determined by mass spectrometry (i.e., 10,963 Da). rAmb a 6 formed oligomers as determined by SDS-PAGE under non-reducing conditions. According to multiple sequence comparisons, Amb a 6 was a distinct nsLTP with less than 40% sequence identity to currently known plant nsLTP allergens, except for nsLTP from Helianthus (i.e., 52%). rAmb a 6 is an important ragweed allergen recognized by 30% of ragweed pollen allergic patients. For certain patients, rAmb a 6-specific IgE levels were higher than those specific for the major ragweed allergen Amb a 1 and analysis also showed a higher allergenic activity in the basophil activation test. rAmb a 6-positive patients suffered mainly from respiratory symptoms. The assumption that Amb a 6 is a source-specific ragweed allergen is supported by the finding that none of the patients showing rAmb a 6-induced basophil activation reacted with Par j 2 and only one rAmb a 6-sensitized patient had a history of plant food allergy. Immunization of rabbits with rAmb a 6 induced IgG antibodies which strongly inhibited IgE binding to rAmb a 6. Our results demonstrate that Amb a 6 is an important source-specific ragweed pollen allergen that should be considered for diagnosis and allergen-specific immunotherapy of ragweed pollen allergy.
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Alérgenos , Antígenos de Plantas , Proteínas Portadoras , Inmunoglobulina E , Humanos , Alérgenos/inmunología , Inmunoglobulina E/inmunología , Antígenos de Plantas/inmunología , Antígenos de Plantas/química , Animales , Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismo , Proteínas de Plantas/inmunología , Proteínas de Plantas/química , Femenino , Rinitis Alérgica Estacional/inmunología , Masculino , Adulto , Ambrosia/inmunología , Spodoptera/inmunología , Proteínas Recombinantes/inmunología , Secuencia de Aminoácidos , Células Sf9 , Persona de Mediana Edad , Extractos VegetalesRESUMEN
Reticulocyte-binding protein homologue 5 (RH5), a leading blood-stage Plasmodium falciparum malaria vaccine target, interacts with cysteine-rich protective antigen (CyRPA) and RH5-interacting protein (RIPR) to form an essential heterotrimeric "RCR-complex". We investigate whether RCR-complex vaccination can improve upon RH5 alone. Using monoclonal antibodies (mAbs) we show that parasite growth-inhibitory epitopes on each antigen are surface-exposed on the RCR-complex and that mAb pairs targeting different antigens can function additively or synergistically. However, immunisation of female rats with the RCR-complex fails to outperform RH5 alone due to immuno-dominance of RIPR coupled with inferior potency of anti-RIPR polyclonal IgG. We identify that all growth-inhibitory antibody epitopes of RIPR cluster within the C-terminal EGF-like domains and that a fusion of these domains to CyRPA, called "R78C", combined with RH5, improves the level of in vitro parasite growth inhibition compared to RH5 alone. These preclinical data justify the advancement of the RH5.1 + R78C/Matrix-M™ vaccine candidate to Phase 1 clinical trial.
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Anticuerpos Monoclonales , Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Vacunas contra la Malaria , Malaria Falciparum , Plasmodium falciparum , Proteínas Protozoarias , Vacunas contra la Malaria/inmunología , Vacunas contra la Malaria/administración & dosificación , Animales , Plasmodium falciparum/inmunología , Proteínas Protozoarias/inmunología , Femenino , Malaria Falciparum/prevención & control , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Antígenos de Protozoos/inmunología , Ratas , Anticuerpos Antiprotozoarios/inmunología , Anticuerpos Monoclonales/inmunología , Humanos , Epítopos/inmunología , Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismoRESUMEN
Background: Immunopathology in food allergy is characterized by an uncontrolled type 2 immune response and specific-IgE production. Recent studies have determined that group 2 innate lymphoid cells (ILC2) participate in the food allergy pathogenic mechanism and their severity. Our objective was to investigate the role of ILC2 in peach-allergic patients due to non-specific lipid transfer protein (Pru p 3) sensitization. Methods: The immune response in peripheral blood mononuclear cells was characterized in lipid transfer protein-allergic patients and healthy controls. We have analyzed the Pru p 3 uptake on ILC2, the expression of costimulatory molecules, and their involvement on the T-cell proliferative response and cytokine production under different experimental conditions: cytokines involved in group 2 innate lymphoid cell activation (IL-33 and IL-25), Pru p 3 as main food allergen, and the combination of both components (IL-33/IL-25+Pru p 3) using cell sorting, EliSpot, flow cytometry, and confocal microscopy. Results: Our results show that Pru p 3 allergen is taken up by group 2 innate lymphoid cells, regulating their costimulatory molecule expression (CD83 and HLA-DR) depending on the presence of Pru p 3 and its combination with IL-33/IL-25. The Pru p 3-stimulated ILC2 induced specific GATA3+Th2 proliferation and cytokine (IL-4, IL-5, and IL-13) production in lipid transfer protein-allergic patients in a cell contact-dependent manner with no changes in Tbet+Th1- and FOXP3+Treg cell differentiation. Conclusions: The results indicate that in lipid transfer protein-allergic patients, the responsible allergen, Pru p 3, interacts with group 2 innate lymphoid cells, promoting a Th2 cell response. Our results might be of interest in vivo, as they show a role of group 2 innate lymphoid cells as antigen-presenting cells, contributing to the development of food allergy. Consequently, group 2 innate lymphoid cells may be considered as potential therapeutic targets.
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Antígenos de Plantas , Proteínas Portadoras , Hipersensibilidad a los Alimentos , Inmunidad Innata , Humanos , Hipersensibilidad a los Alimentos/inmunología , Femenino , Antígenos de Plantas/inmunología , Proteínas Portadoras/inmunología , Masculino , Adulto , Citocinas/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Proteínas de Plantas/inmunología , Activación de Linfocitos/inmunología , Adulto Joven , Persona de Mediana EdadRESUMEN
BACKGROUND: Detection of viruses by host pattern recognition receptors induces the expression of type I interferon (IFN) and IFN-stimulated genes (ISGs), which suppress viral replication. Numerous studies have described HIV-1 as a poor activator of innate immunity in vitro. The exact role that the viral capsid plays in this immune evasion is not fully understood. RESULTS: To better understand the role of the HIV-1 capsid in sensing we tested the effect of making HIV-1 by co-expressing a truncated Gag that encodes the first 107 amino acids of capsid fused with luciferase or GFP, alongside wild type Gag-pol. We found that unlike wild type HIV-1, viral particles produced with a mixture of wild type and truncated Gag fused to luciferase or GFP induced a potent IFN response in THP-1 cells and macrophages. Innate immune activation by Gag-fusion HIV-1 was dependent on reverse transcription and DNA sensor cGAS, suggesting activation of an IFN response by viral DNA. Further investigation revealed incorporation of the Gag-luciferase/GFP fusion proteins into viral particles that correlated with subtle defects in wild type Gag cleavage and a diminished capacity to saturate restriction factor TRIM5α, likely due to aberrant particle formation. We propose that expression of the Gag fusion protein disturbs the correct cleavage and maturation of wild type Gag, yielding viral particles that are unable to effectively shield viral DNA from detection by innate sensors including cGAS. CONCLUSIONS: These data highlight the crucial role of capsid in innate evasion and support growing literature that disruption of Gag cleavage and capsid formation induces a viral DNA- and cGAS-dependent innate immune response. Together these data demonstrate a protective role for capsid and suggest that antiviral activity of capsid-targeting antivirals may benefit from enhanced innate and adaptive immunity in vivo.
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VIH-1 , Inmunidad Innata , Nucleotidiltransferasas , Productos del Gen gag del Virus de la Inmunodeficiencia Humana , VIH-1/inmunología , VIH-1/genética , VIH-1/fisiología , Humanos , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/metabolismo , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Factores de Restricción Antivirales , Macrófagos/inmunología , Macrófagos/virología , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Células THP-1 , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Proteínas Portadoras/inmunología , Evasión Inmune , Cápside/metabolismo , Cápside/inmunología , Replicación Viral , Virión/metabolismo , Virión/genética , Virión/inmunología , Interacciones Huésped-Patógeno/inmunología , ADN Viral/genética , Línea CelularRESUMEN
Bacterial or viral antigens can contain subdominant protein regions that elicit weak antibody responses upon vaccination or infection although there is accumulating evidence that antibody responses against subdominant regions can enhance the protective immune response. One proposed mechanism for subdominant protein regions is the binding of host proteins that prevent antibody production against epitopes hidden within the protein binding interfaces. Here, we used affinity purification combined with quantitative mass spectrometry (AP-MS) to examine the level of competition between antigen-specific antibodies and host-pathogen protein interaction networks using the M1 protein from Streptococcus pyogenes as a model system. As most humans have circulating antibodies against the M1 protein, we first used AP-MS to show that the M1 protein interspecies protein network formed with human plasma proteins is largely conserved in naïve mice. Immunizing mice with the M1 protein generated a time-dependent increase of anti-M1 antibodies. AP-MS analysis comparing the composition of the M1-plasma protein network from naïve and immunized mice showed significant enrichment of 292 IgG peptides associated with 56 IgG chains in the immune mice. Despite the significant increase of bound IgGs, the levels of interacting plasma proteins were not significantly reduced in the immune mice. The results indicate that the antigen-specific polyclonal IgG against the M1 protein primarily targets epitopes outside the other plasma protein binding interfaces. In conclusion, this study demonstrates that AP-MS is a promising strategy to determine the relationship between antigen-specific antibodies and host-pathogen interaction networks that could be used to define subdominant protein regions of relevance for vaccine development.
Asunto(s)
Antígenos Bacterianos , Inmunoglobulina G , Unión Proteica , Streptococcus pyogenes , Animales , Streptococcus pyogenes/inmunología , Streptococcus pyogenes/metabolismo , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/metabolismo , Ratones , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Inmunidad Adaptativa , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/metabolismo , Anticuerpos Antibacterianos/inmunología , Mapas de Interacción de Proteínas , Espectrometría de Masas , Proteínas Portadoras/metabolismo , Proteínas Portadoras/inmunología , Femenino , Interacciones Huésped-Patógeno/inmunologíaRESUMEN
Ndel1 oligopeptidase activity shows promise as a potential biomarker for diagnosing schizophrenia (SCZ) and monitoring early-stage pharmacotherapy. Ndel1 plays a pivotal role in critical aspects of brain development, such as neurite outgrowth, neuronal migration, and embryonic brain formation, making it particularly relevant to neurodevelopmental disorders like SCZ. Currently, the most specific inhibitor for Ndel1 is the polyclonal anti-Ndel1 antibody (NOAb), known for its high specificity and efficient anti-catalytic activity. NOAb has been vital in measuring Ndel1 activity in humans and animal models, enabling the prediction of pharmacological responses to antipsychotics in studies with patients and animals. To advance our understanding of in vivo Ndel1 function and develop drugs for mental disorders, identifying small chemical compounds capable of specifically inhibiting Ndel1 oligopeptidase is crucial, including within living cells. Due to challenges in obtaining Ndel1's three-dimensional structure and its promiscuous substrate recognition, we conducted a high-throughput screening (HTS) of 2,400 small molecules. Nine compounds with IC50-values ranging from 7 to 56 µM were identified as potent Ndel1 inhibitors. Notably, one compound showed similar efficacy to NOAb and inhibited Ndel1 within living cells, although its in vivo use may pose toxicity concerns. Despite this, all identified compounds hold promise as candidates for further refinement through rational drug design, aiming to enhance their inhibitory efficacy, specificity, stability, and biodistribution. Our ultimate goal is to develop druggable Ndel1 inhibitors that can improve the treatment and support the diagnosis of psychiatric disorders like SCZ.
Asunto(s)
Anticuerpos , Esquizofrenia , Animales , Humanos , Biomarcadores , Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismo , Ensayos Analíticos de Alto Rendimiento , Esquizofrenia/diagnóstico , Esquizofrenia/terapia , Distribución Tisular , Anticuerpos/farmacología , Anticuerpos/uso terapéuticoRESUMEN
Coiled coil-forming M proteins of the widespread and potentially deadly bacterial pathogen Streptococcus pyogenes (strep A) are immunodominant targets of opsonizing antibodies. However, antigenic sequence variability of M proteins into >220 M types, as defined by their hypervariable regions (HVRs), is considered to limit M proteins as vaccine immunogens because of type specificity in the antibody response. Surprisingly, a multi-HVR immunogen in clinical vaccine trials was shown to elicit M-type crossreactivity. The basis for this crossreactivity is unknown but may be due in part to antibody recognition of a 3D pattern conserved in many M protein HVRs that confers binding to human complement C4b-binding protein (C4BP). To test this hypothesis, we investigated whether a single M protein immunogen carrying the 3D pattern would elicit crossreactivity against other M types carrying the 3D pattern. We found that a 34-amino acid sequence of S. pyogenes M2 protein bearing the 3D pattern retained full C4BP-binding capacity when fused to a coiled coil-stabilizing sequence from the protein GCN4. We show that this immunogen, called M2G, elicited cross-reactive antibodies against a number of M types that carry the 3D pattern but not against those that lack the 3D pattern. We further show that the M2G antiserum-recognized M proteins displayed natively on the strep A surface and promoted the opsonophagocytic killing of strep A strains expressing these M proteins. As C4BP binding is a conserved virulence trait of strep A, we propose that targeting the 3D pattern may prove advantageous in vaccine design.
Asunto(s)
Antígenos Bacterianos , Proteínas de la Membrana Bacteriana Externa , Proteínas Portadoras , Streptococcus pyogenes , Humanos , Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Portadoras/química , Proteínas Portadoras/inmunología , Unión Proteica , Streptococcus pyogenes/inmunología , Reacciones CruzadasRESUMEN
Autophagy induction by starvation has been shown to enhance lysosomal delivery to mycobacterial phagosomes, resulting in the restriction of the Mycobacterium tuberculosis reference strain H37Rv. In contrast to H37Rv, our previous study showed that strains belonging to the notorious M. tuberculosis Beijing genotype could evade autophagic elimination. Our recent RNA-Seq analysis also discovered that the autophagy-resistant M. tuberculosis Beijing strain (BJN) evaded autophagic control by upregulating the expression of Kxd1, a BORC complex component, and Plekhm2, both of which function in lysosome positioning towards the cell periphery in host macrophages, thereby suppressing enhanced lysosomal delivery to its phagosome and sparing the BJN from elimination as a result. In this work, we further characterised the other specific components of the BORC complex, BORC5-8, and Kinesin proteins in autophagy resistance by the BJN. Depletion of BORCS5-8 and Kinesin-1, but not Kinesin-3, reverted autophagy avoidance by the BJN, resulting in increased lysosomal delivery to the BJN phagosomes. In addition, the augmented lysosome relocation towards the perinuclear region could now be observed in the BJN-infected host cells depleted in BORCS5-8 and Kinesin-1 expressions. Taken together, the data uncovered new roles for BORCS5-8 and Kinesin-1 in autophagy evasion by the BJN.
Asunto(s)
Autofagia , Cinesinas , Mycobacterium tuberculosis , Tuberculosis , Humanos , Autofagia/genética , Autofagia/inmunología , Beijing , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Cinesinas/genética , Cinesinas/inmunología , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/inmunología , Tuberculosis/genética , Tuberculosis/inmunología , Macrófagos/inmunologíaRESUMEN
Bone Marrow Stromal Cell Antigen 2 (BST2) is a type II transmembrane protein expressed on various cell types that tethers the release of viruses. Natural killer (NK) cells express low levels of BST2 under normal conditions but exhibit increased expression of BST2 upon activation. In this study, we show for the first time that murine BST2 can control the cytotoxicity of NK cells. The cytoplasmic tail of murine BST2 contains an immunoreceptor tyrosine-based inhibitory motif (ITIM). The absence of BST2 on NK cells can enhance their cytotoxicity against tumor cells compared to wild type NK cells. NK cells isolated from NZW mice, which express ITIM-deficient BST2, also showed higher cytotoxicity than wild type NK cells. In addition, we found that galectin-8 and galectin-9 were ligands of BST2, since blocking galectin-8 or -9 with monoclonal antibodies enhanced the cytotoxicity of NK cells. These results suggested that BST2 might be a novel NK cell inhibitory receptor as it was involved in regulating NK cell cytotoxicity through its interaction with galectins.
Asunto(s)
Antígeno 2 del Estroma de la Médula Ósea , Citotoxicidad Inmunológica , Células Asesinas Naturales , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD/genética , Antígenos CD/inmunología , Antígeno 2 del Estroma de la Médula Ósea/genética , Antígeno 2 del Estroma de la Médula Ósea/inmunología , Proteínas Portadoras/inmunología , Citotoxicidad Inmunológica/genética , Citotoxicidad Inmunológica/inmunología , Galectinas/inmunología , Células Asesinas Naturales/inmunología , Ligandos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , Tirosina/metabolismoRESUMEN
Pyruvate kinase (PK) is a key enzyme that catalyzes the dephosphorylation of phosphoenolpyruvate (PEP) into pyruvate, and is responsible for the production of ATP during glycolysis. As another important isozyme of PK, pyruvate kinase M2 (PKM2) exists in cells with high levels of nucleic acid synthesis, such as normal proliferating cells (e.g., lymphocytes and intestinal epithelial cells), embryonic cells, adult stem cells, and tumor cells. With further research, PKM2, as an important regulator of cellular pathophysiological activity, has attracted increasing attention in the process of autoimmune response and inflammatory. In this re]view, we examine the contribution of PKM2 to the human immune response. Further studies on the immune mechanisms of PKM2 are expected to provide more new ideas and drug targets for immunotherapy of inflammatory and autoimmune diseases, guiding drug development and disease treatment.