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1.
iScience ; 27(4): 109439, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38523774

RESUMEN

The global incidence of human papillomavirus (HPV) associated head and neck carcinoma is on the rise, in response to this a tetravalent therapeutic vaccine named Qß-HPVag was developed. This vaccine, utilizing virus-like particles (VLPs) loaded with toll-like receptor ligands and chemically coupled to four HPV16-derived peptides, demonstrated strong anti-tumor effects in a murine head and neck cancer model. Qß-HPVag impeded tumor progression, increased infiltration of HPV-specific T cells, and significantly improved survival. The vaccine`s efficacy was associated with immune repolarization in the tumor microenvironment, characterized by expanded activated dendritic cell subsets (cDC1, cDC2, DC3). Notably, mice responding to treatment exhibited a higher percentage of migratory DC3 cells expressing CCR7. These findings suggest promising prospects for optimized VLP-based vaccines in treating HPV-associated head and neck cancer.

2.
J Vet Intern Med ; 38(1): 205-215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37991136

RESUMEN

BACKGROUND: Amyloid A (AA) amyloidosis is a protein misfolding disease arising from serum amyloid A (SAA). Systemic AA amyloidosis recently was shown to have a high prevalence in shelter cats in Italy and was associated with azotemia and proteinuria. OBJECTIVES: Investigate urine protein profiles and diagnostic biomarkers in cats with renal AA amyloidosis. ANIMALS: Twenty-nine shelter cats. METHODS: Case-control study. Cats with renal proteinuria that died or were euthanized between 2018 and 2021 with available necropsy kidney, liver and spleen samples, and with surplus urine collected within 30 days before death, were included. Histology was used to characterize renal damage and amyloid amount and distribution; immunohistochemistry was used to confirm AA amyloidosis. Urine protein-to-creatinine (UPC) and urine amyloid A-to-creatinine (UAAC) ratios were calculated, and sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) and liquid chromatography-mass spectrometry (LC-MS) of proteins were performed. RESULTS: Twenty-nine cats were included. Nineteen had AA amyloidosis with renal involvement. Cats with AA amyloidosis had a higher UPC (median, 3.9; range, 0.6-12.7 vs 1.5; 0.6-3.1; P = .03) and UAAC ratios (median, 7.18 × 10-3 ; range, 23 × 10-3 -21.29 × 10-3 vs 1.26 × 10-3 ; 0.21 × 10-3 -6.33 × 10-3 ; P = .04) than unaffected cats. The SDS-AGE identified mixed-type proteinuria in 89.4% of cats with AA amyloidosis and in 55.6% without AA amyloidosis (P = .57). The LC-MS identified 63 potential biomarkers associated with AA amyloidosis (P < .05). Among these, urine apolipoprotein C-III was higher in cats with AA amyloidosis (median, 1.38 × 107 ; range, 1.85 × 105 -5.29 × 107 vs 1.76 × 106 ; 0.0 × 100 -1.38 × 107 ; P = .01). In the kidney, AA-amyloidosis was associated with glomerulosclerosis (P = .02) and interstitial fibrosis (P = .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Renal AA amyloidosis is associated with kidney lesions, increased proteinuria and increased urine excretion of SAA in shelter cats. Additional studies are needed to characterize the role of lipid transport proteins in the urine of affected cats.


Asunto(s)
Amiloidosis , Enfermedades de los Gatos , Gatos , Animales , Creatinina , Estudios de Casos y Controles , Riñón/patología , Amiloidosis/complicaciones , Amiloidosis/veterinaria , Proteinuria/veterinaria , Proteinuria/metabolismo , Proteína Amiloide A Sérica/metabolismo , Enfermedades de los Gatos/patología
3.
PLoS One ; 18(11): e0293892, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37917747

RESUMEN

Amyloidosis is a group of protein-misfolding disorders characterized by the accumulation of amyloid in organs, both in humans and animals. AA-amyloidosis is considered a reactive type of amyloidosis and in humans is characterized by the deposition of AA-amyloid fibrils in one or more organs. In domestic shorthair cats, AA-amyloidosis was recently reported to be frequent in shelters. To better characterize this pathology, we report the distribution of amyloid deposits and associated histological lesions in the organs of shelter cats with systemic AA-amyloidosis. AA-amyloid deposits were identified with Congo Red staining and immunofluorescence. AA-amyloid deposits were then described and scored, and associated histological lesions were reported. Based on Congo Red staining and immunofluorescence nine shelter cats presented systemic AA-amyloidosis. The kidney (9/9), the spleen (8/8), the adrenal glands (8/8), the small intestine (7/7) and the liver (8/9) were the organs most involved by amyloid deposits, with multifocal to diffuse and from moderate to severe deposits, both in the organ parenchyma and/or in the vascular compartment. The lung (2/9) and the skin (1/8) were the least frequently involved organs and deposits were mainly focal to multifocal, mild, vascular and perivascular. Interestingly, among the organs with fibril deposition, the stomach (7/9), the gallbladder (6/6), the urinary bladder (3/9), and the heart (6/7) were reported for the first time in cats. All eye, brain and skeletal muscle samples had no amyloid deposits. An inflammatory condition was identified in 8/9 cats, with chronic enteritis and chronic nephritis being the most common. Except for secondary cell compression, other lesions were not associated to amyloid deposits. To conclude, this study gives new insights into the distribution of AA-amyloid deposits in cats. A concurrent chronic inflammation was present in almost all cases, possibly suggesting a relationship with AA-amyloidosis.


Asunto(s)
Amiloidosis , Amiloidosis de Cadenas Ligeras de las Inmunoglobulinas , Humanos , Gatos , Animales , Placa Amiloide/complicaciones , Rojo Congo , Amiloidosis/patología , Amiloidosis de Cadenas Ligeras de las Inmunoglobulinas/complicaciones , Amiloide , Proteína Amiloide A Sérica , Proteínas Amiloidogénicas
4.
PLoS One ; 18(3): e0281822, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36989207

RESUMEN

Systemic AA-amyloidosis is a protein-misfolding disease characterized by fibril deposition of serum amyloid-A protein (SAA) in several organs in humans and many animal species. Fibril deposits originate from abnormally high serum levels of SAA during chronic inflammation. A high prevalence of AA-amyloidosis has been reported in captive cheetahs and a horizontal transmission has been proposed. In domestic cats, AA-amyloidosis has been mainly described in predisposed breeds but only rarely reported in domestic short-hair cats. Aims of the study were to determine AA-amyloidosis prevalence in dead shelter cats. Liver, kidney, spleen and bile were collected at death in cats from 3 shelters. AA-amyloidosis was scored. Shedding of amyloid fibrils was investigated with western blot in bile and scored. Descriptive statistics were calculated. In the three shelters investigated, prevalence of AA-amyloidosis was 57.1% (16/28 cats), 73.0% (19/26) and 52.0% (13/25), respectively. In 72.9% of cats (35 in total) three organs were affected concurrently. Histopathology and immunofluorescence of post-mortem extracted deposits identified SAA as the major protein source. The duration of stay in the shelters was positively associated with a histological score of AA-amyloidosis (B = 0.026, CI95% = 0.007-0.046; p = 0.010). AA-amyloidosis was very frequent in shelter cats. Presence of SAA fragments in bile secretions raises the possibility of fecal-oral transmission of the disease. In conclusion, AA-amyloidosis was very frequent in shelter cats and those staying longer had more deposits. The cat may represent a natural model of AA-amyloidosis.


Asunto(s)
Acinonyx , Amiloidosis , Amiloidosis de Cadenas Ligeras de las Inmunoglobulinas , Humanos , Gatos , Animales , Amiloidosis/epidemiología , Amiloidosis/veterinaria , Amiloide , Proteína Amiloide A Sérica/metabolismo
5.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36835301

RESUMEN

Alzheimer's disease (AD) is the most common form of dementia and may contribute to 60-70% of cases. Worldwide, around 50 million people suffer from dementia and the prediction is that the number will more than triple by 2050, as the population ages. Extracellular protein aggregation and plaque deposition as well as accumulation of intracellular neurofibrillary tangles, all leading to neurodegeneration, are the hallmarks of brains with Alzheimer's disease. Therapeutic strategies including active and passive immunizations have been widely explored in the last two decades. Several compounds have shown promising results in many AD animal models. To date, only symptomatic treatments are available and because of the alarming epidemiological data, novel therapeutic strategies to prevent, mitigate, or delay the onset of AD are required. In this mini-review, we focus on our understanding of AD pathobiology and discuss current active and passive immunomodulating therapies targeting amyloid-ß protein.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Inmunoterapia , Animales , Enfermedad de Alzheimer/terapia , Péptidos beta-Amiloides/metabolismo , Inmunoterapia/métodos , Ovillos Neurofibrilares/metabolismo , Placa Amiloide/metabolismo , Humanos , Modelos Animales de Enfermedad
6.
Q J Exp Psychol (Hove) ; 76(7): 1561-1584, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36062350

RESUMEN

The role of meaning facets based on sensorimotor experiences is well investigated in comprehension but has received little attention in language production research. In two experiments, we investigated whether experiential traces of space influenced lexical choices when participants completed visually presented sentence fragments (e.g., "You are at the sea and you see a . . .") with spoken nouns (e.g., "dolphin," "palm tree"). The words were presented consecutively in an ascending or descending direction, starting from the centre of the screen. These physical spatial cues did not influence lexical choices. However, the produced nouns met the spatial characteristics of the broader sentence contexts such that the typical spatial locations of the produced noun referents were predicted by the location of the situations described by the sentence fragments (i.e., upper or lower sphere). By including distributional semantic similarity measures derived from computing cosine values between sentence nouns and produced nouns using a web-based text corpus, we show that the meaning dimension of "location in space" guides lexical selection during speaking. We discuss the relation of this spatial meaning dimension to accounts of experientially grounded and usage-based theories of language processing and their combination in hybrid approaches. In doing so, we contribute to a more comprehensive understanding of the many facets of meaning processing during language production and their impact on the words we select to express verbal messages.


Asunto(s)
Comprensión , Lenguaje , Semántica , Señales (Psicología)
7.
Nat Commun ; 13(1): 7041, 2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36396658

RESUMEN

AA amyloidosis is a systemic disease characterized by deposition of misfolded serum amyloid A protein (SAA) into cross-ß amyloid in multiple organs in humans and animals. AA amyloidosis occurs at high SAA serum levels during chronic inflammation. Prion-like transmission was reported as possible cause of extreme AA amyloidosis prevalence in captive animals, e.g. 70% in cheetah and 57-73% in domestic short hair (DSH) cats kept in zoos and shelters, respectively. Herein, we present the 3.3 Å cryo-EM structure of AA amyloid extracted post-mortem from the kidney of a DSH cat with renal failure, deceased in a shelter with extreme disease prevalence. The structure reveals a cross-ß architecture assembled from two 76-residue long proto-filaments. Despite >70% sequence homology to mouse and human SAA, the cat SAA variant adopts a distinct amyloid fold. Inclusion of an eight-residue insert unique to feline SAA contributes to increased amyloid stability. The presented feline AA amyloid structure is fully compatible with the 99% identical amino acid sequence of amyloid fragments of captive cheetah.


Asunto(s)
Acinonyx , Amiloidosis , Animales , Gatos , Ratones , Acinonyx/metabolismo , Amiloide/metabolismo , Amiloidosis/metabolismo , Microscopía por Crioelectrón , Prevalencia , Proteína Amiloide A Sérica/metabolismo
8.
Clin Cancer Res ; 28(23): 5190-5201, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36166004

RESUMEN

PURPOSE: Advanced-stage gastrointestinal cancers represent a high unmet need requiring new effective therapies. We investigated the antitumor activity of a novel T cell-engaging antibody (B7-H6/CD3 ITE) targeting B7-H6, a tumor-associated antigen that is expressed in gastrointestinal tumors. EXPERIMENTAL DESIGN: Membrane proteomics and IHC analysis identified B7-H6 as a tumor-associated antigen in gastrointestinal tumor tissues with no to very little expression in normal tissues. The antitumor activity and mode of action of B7-H6/CD3 ITE was evaluated in in vitro coculture assays, in humanized mouse tumor models, and in colorectal cancer precision cut tumor slice cultures. RESULTS: B7-H6 expression was detected in 98% of colorectal cancer, 77% of gastric cancer, and 63% of pancreatic cancer tissue samples. B7-H6/CD3 ITE-mediated redirection of T cells toward B7-H6-positive tumor cells resulted in B7-H6-dependent lysis of tumor cells, activation and proliferation of T cells, and cytokine secretion in in vitro coculture assays, and infiltration of T cells into tumor tissues associated with tumor regression in in vivo colorectal cancer models. In primary patient-derived colorectal cancer precision-cut tumor slice cultures, treatment with B7-H6/CD3 ITE elicited cytokine secretion by endogenous tumor-infiltrating immune cells. Combination with anti-PD-1 further enhanced the activity of the B7-H6/CD3 ITE. CONCLUSION: These data highlight the potential of the B7-H6/CD3 ITE to induce T cell-redirected lysis of tumor cells and recruitment of T cells into noninflamed tumor tissues, leading to antitumor activity in in vitro, in vivo, and human tumor slice cultures, which supports further evaluation in a clinical study.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Gastrointestinales , Ratones , Animales , Humanos , Antígenos B7/metabolismo , Neoplasias Gastrointestinales/tratamiento farmacológico , Linfocitos T , Neoplasias Colorrectales/tratamiento farmacológico , Citocinas , Inmunoglobulina G
9.
Front Immunol ; 13: 1008764, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36159851

RESUMEN

Colorectal cancer (CRC) is one of the most common cancers worldwide and demands more effective treatments. We sought to identify tumor selective CRC antigens and their therapeutic potential for cytotoxic T-cell targeting by transcriptomic and immunohistochemical analysis. LY6G6D was identified as a tumor selectively expressed CRC antigen, mainly in the microsatellite stable (MSS) subtype. A specific anti LY6G6D/CD3 T cell engager (TcE) was generated and demonstrated potent tumor cell killing and T cell activation in vitro. Ex vivo treatment of primary patient-derived CRC tumor slice cultures with the LY6G6D/CD3 TcE led to IFNγ secretion in LY6G6D positive tumor samples. In vivo, LY6G6D/CD3 TcE monotherapy demonstrated tumor regressions in pre-clinical mouse models of engrafted human CRC tumor cells and PBMCs. Lastly, 2D and 3D cocultures of LY6G6D positive and negative cells were used to explore the bystander killing of LY6G6D negative cells after specific activation of T cells by LY6G6D positive cells. LY6G6D/CD3 TcE treatment was shown to lyse target negative cells in the vicinity of target positive cells through a combined effect of IFNγ, TNFα and Fas/FasL. In summary, LY6G6D was identified as a selectively expressed CRC antigen that can be utilized to potently re-direct and activate cytotoxic T-cells to lyse LY6G6D expressing CRC using a TcE. This effect can be spread to target negative neighboring tumor cells, potentially leading to improved therapeutic efficacy.


Asunto(s)
Neoplasias Colorrectales , Factor de Necrosis Tumoral alfa , Animales , Antígenos de Neoplasias , Humanos , Inmunoglobulinas , Activación de Linfocitos , Ratones , Linfocitos T Citotóxicos
10.
Front Immunol ; 13: 862757, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35967294

RESUMEN

VISTA (PD-1H) is an immune regulatory molecule considered part of the next wave of immuno-oncology targets. VISTA is an immunoglobulin (Ig) superfamily cell surface molecule mainly expressed on myeloid cells, and to some extent on NK cells and T cells. In previous preclinical studies, some VISTA-targeting antibodies provided immune inhibitory signals, while other antibodies triggered immune stimulatory signals. Importantly, for therapeutic antibodies, the isotype backbone can have a strong impact on antibody function. To elucidate the mode of action of immune stimulatory anti-VISTA antibodies, we studied three different anti-human VISTA antibody clones, each on three different IgG isotypes currently used for therapeutic antibodies: unaltered IgG1 (IgG1-WT), IgG1-KO (IgG1-LL234,235AA-variant with reduced Fc-effector function), and IgG4-Pro (IgG4- S228P-variant with stabilized hinge region). Antibody functionality was analysed in mixed leukocyte reaction (MLR) of human peripheral blood mononuclear cells (PBMCs), as a model system for ongoing immune reactions, on unstimulated human PBMCs, as a model system for a resting immune system, and also on acute myeloid leukemia (AML) patient samples to evaluate anti-VISTA antibody effects on primary tumor material. The functions of three anti-human VISTA antibodies were determined by their IgG isotype backbones. An MLR of healthy donor PBMCs was effectively augmented by anti-VISTA-IgG4-Pro and anti-VISTA-IgG1-WT antibodies, as indicated by increased levels of cytokines, T cell activation markers and T cell proliferation. However, in a culture of unstimulated PBMCs of single healthy donors, only anti-VISTA-IgG1-WT antibodies increased the activation marker HLA-DR on resting myeloid cells, and chemokine levels. Interestingly, interactions with different Fc-receptors were required for these effects, namely CD64 for augmentation of MLR, and CD16 for activation of resting myeloid cells. Furthermore, anti-VISTA-IgG1-KO antibodies had nearly no impact in any model system. Similarly, in AML patient samples, anti-VISTA-antibody on IgG4-Pro backbone, but not on IgG1-KO backbone, increased interactions, as a novel readout of activity, between immune cells and CD34+ AML cancer cells. In conclusion, the immune stimulatory effects of antagonistic anti-VISTA antibodies are defined by the antibody isotype and interaction with different Fc-gamma-receptors, highlighting the importance of understanding these interactions when designing immune stimulatory antibody therapeutics for immuno-oncology applications.


Asunto(s)
Antígenos B7/inmunología , Neoplasias , Receptores Fc , Humanos , Inmunoglobulina G , Leucocitos Mononucleares , Receptores de IgG
11.
Front Immunol ; 13: 864718, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35784292

RESUMEN

mRNA based vaccines against COVID-19 have proven most successful at keeping SARS-CoV-2 pandemic at bay in many countries. Recently, there is an increased interest in heterologous prime-boost vaccination strategies for COVID-19 to maintain antibody responses for the control of continuously emerging SARS-CoV-2 variants of concern (VoCs) and to overcome other obstacles such as supply shortage, costs and reduced safety issues or inadequatly induced immune-responses. In this study, we investigated the antibody responses induced by heterologous prime-boost with vaccines based on mRNA and virus-like particles (VLPs). The VLP-based mCuMVTT-RBM vaccine candidate and the approved mRNA-1273 vaccine were used for this purpose. We find that homologous prime boost regimens with either mRNA or VLP induced high levels of high avidity antibodies. Optimal antibody responses were, however, induced by heterologous regimens both for priming with mRNA and boosting with VLP and vice versa, priming with VLP and boosting with mRNA. Thus, heterologous prime boost strategies may be able to optimize efficacy and economics of novel vaccine strategies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Vacuna nCoV-2019 mRNA-1273 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunoglobulina G , ARN Mensajero/genética , SARS-CoV-2/genética
12.
Oncoimmunology ; 11(1): 2080328, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35756842

RESUMEN

Upregulation of inhibitory receptors, such as lymphocyte activation gene-3 (LAG-3), may limit the antitumor activity of therapeutic antibodies targeting the programmed cell death protein-1 (PD-1) pathway. We describe the binding properties of ezabenlimab, an anti-human PD-1 antibody, and BI 754111, an anti-human LAG-3 antibody, and assess their activity alone and in combination. Ezabenlimab bound with high affinity to human PD-1 (KD = 6 nM) and blocked the interaction of PD-1 with PD-L1 and PD-L2. Ezabenlimab dose-dependently increased interferon-γ secretion in human T cells expressing PD-1 in co-culture with PD-L1-expressing dendritic cells. Administration of ezabenlimab to human PD-1 knock-in mice dose-dependently inhibited growth of MC38 tumors. To reduce immunogenicity, ezabenlimab was reformatted from a human IgG4 to a chimeric variant with a mouse IgG1 backbone (BI 905725) for further in vivo studies. Combining BI 905725 with anti-mouse LAG-3 antibodies improved antitumor activity versus BI 905725 monotherapy in the MC38 tumor model. We generated BI 754111, which bound with high affinity to human LAG-3 and prevented LAG-3 interaction with its ligand, major histocompatibility complex class II. In an in vitro model of antigen-experienced memory T cells expressing PD-1 and LAG-3, interferon-γ secretion increased by an average 1.8-fold versus isotype control (p = 0.027) with BI 754111 monotherapy, 6.9-fold (p < 0.0001) with ezabenlimab monotherapy and 13.2-fold (p < 0.0001) with BI 754111 plus ezabenlimab. Overall, ezabenlimab and BI 754111 bound to their respective targets with high affinity and prevented ligand binding. Combining ezabenlimab with BI 754111 enhanced in vitro activity versus monotherapy, supporting clinical investigation of this combination (NCT03156114; NCT03433898).


Asunto(s)
Antígeno B7-H1 , Receptor de Muerte Celular Programada 1 , Animales , Anticuerpos Bloqueadores , Anticuerpos Monoclonales/farmacología , Estudios Clínicos como Asunto , Inhibidores de Puntos de Control Inmunológico , Interferón gamma , Ligandos , Ratones
13.
J Surg Res ; 279: 1-7, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35716445

RESUMEN

INTRODUCTION: Transfer of trauma patients whose injuries are deemed unsurvivable, often results in early death or transition to comfort care and could be considered misuse of health care resources. This is particularly true where tertiary care resources are limited. Identifying riskfactors for and predicting futile transfers could reduce this impact and help to optimize triage and management. METHODS: A retrospective study of interfacility trauma transfers to a single rural Level I rauma center from 2014 to 2019. Futility was defined as death, hospice, or declaration of comfort measures within 48 h of transfer without procedural or radiographic intervention at the accepting center. Multiple logistic regressions identified independent predictors of futile transfers. The predictive power of Mechanism,Glasgow coma scale, Age, and Arterial pressure (MGAP), an injury severity score based on Mechanism, Glasgow coma scale, Age, and systolic blood Pressure, were evaluated. RESULTS: Of the 3368 trauma transfers, 37 (1.1%) met criteria as futile. Futile transfers occurred among patients who were significantly older with falls as the most common mechanism. Age, Glasgow coma scale, systolic blood Pressure and Injury Severity Score were significant (P < 0.05) independent predictors of futile transfer. MGAP had a high predictive power area under the receiver operating characteristic (AUROC 0.864, 95% confidence interval 0.803-0.925) for futility. CONCLUSIONS: A small proportion (1.1%) of transfers to a rural Level I trauma center met criteria for futility. Predictive tools, such as MGAP scoring, can provide objective criteria for evaluation of transfer necessity and prompt care pathways that involve pre-transfer communications, telemedicine, and/or patient centered goals of care discussions. Such tools could be used in conjunction with a more granular assessment regarding potential operational barriers to reduce futile transfers and to enhance optimization of resource utilization in low-resource service areas.


Asunto(s)
Centros Traumatológicos , Heridas y Lesiones , Escala de Coma de Glasgow , Humanos , Puntaje de Gravedad del Traumatismo , Inutilidad Médica , Transferencia de Pacientes , Estudios Retrospectivos , Índices de Gravedad del Trauma , Triaje/métodos , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/terapia
14.
Vaccines (Basel) ; 10(5)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35632499

RESUMEN

In this report, we mechanistically reveal how the Variant of Concern (VOC) SARS-CoV-2 Omicron (B.1.1.529) escapes neutralizing antibody responses, by physio-chemical characterization of this variant in comparison to the wild-type Wuhan and the Delta variant (B.1.617.2). Convalescent sera, as well as sera obtained from participants who received two or three doses of mRNA vaccines (Moderna-mRNA-1273® or Pfizer-BNT162b2®), were used for comparison in this study. Our data demonstrate that both Delta, as well as Omicron variants, exhibit a higher affinity for the receptor ACE2, facilitating infection and causing antibody escape by receptor affinity (affinity escape), due to the reduced ability of antibodies to compete with RBD-receptor interaction and virus neutralization. In contrast, only Omicron but not the Delta variant escaped antibody recognition, most likely because only Omicron exhibits the mutation at E484A, a position associated with reduced recognition, resulting in further reduced neutralization (specificity escape). Nevertheless, the immunizations with RNA-based vaccines resulted in marked viral neutralization in vitro for all strains, compatible with the fact that Omicron is still largely susceptible to vaccination-induced antibodies, despite affinity- and specificity escape.

15.
Allergy ; 77(8): 2446-2458, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35403221

RESUMEN

BACKGROUND: The highly contagious SARS-CoV-2 is mainly transmitted by respiratory droplets and aerosols. Consequently, people are required to wear masks and maintain a social distance to avoid spreading of the virus. Despite the success of the commercially available vaccines, the virus is still uncontained globally. Given the tropism of SARS-CoV-2, a mucosal immune reaction would help to reduce viral shedding and transmission locally. Only seven out of hundreds of ongoing clinical trials are testing the intranasal delivery of a vaccine against COVID-19. METHODS: In the current study, we evaluated the immunogenicity of a traditional vaccine platform based on virus-like particles (VLPs) displaying RBD of SARS-CoV-2 for intranasal administration in a murine model. The candidate vaccine platform, CuMVTT -RBD, has been optimized to incorporate a universal T helper cell epitope derived from tetanus-toxin and is self-adjuvanted with TLR7/8 ligands. RESULTS: CuMVTT -RBD vaccine elicited a strong systemic RBD- and spike-IgG and IgA antibodies of high avidity. Local immune response was assessed, and our results demonstrate a strong mucosal antibody and plasma cell production in lung tissue. Furthermore, the induced systemic antibodies could efficiently recognize and neutralize different variants of concern (VOCs). CONCLUSION: Our data demonstrate that intranasal administration of CuMVTT -RBD induces a protective systemic and local specific antibody response against SARS-CoV-2 and its VOCs.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacunas de Partículas Similares a Virus , Administración Intranasal , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Humanos , Ratones , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunas de Partículas Similares a Virus/inmunología
16.
Int J Mol Sci ; 23(5)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35269805

RESUMEN

Intravenous (IV) iron nanoparticle preparations are widely used to treat iron deficiency. The mechanism of mononuclear phagocyte system-mediated clearance of IV iron nanoparticles is unknown. The early uptake and homeostasis of iron after injection of ferric carboxymaltose (FCM) in mice was studied. An increase in serum iron was observed at 2.5 h followed by a return to baseline by 24 h. An increase in circulating monocytes was observed, particularly Ly6Chi and Ly6Clow. FCM was also associated with a time-dependent decrease in liver Kupffer cells (KCs) and increase in liver monocytes. The increase in liver monocytes suggests an influx of iron-rich blood monocytes, while some KCs underwent apoptosis. Adoptive transfer experiments demonstrated that following liver infiltration, blood monocytes differentiated to KCs. KCs were also critical for IV iron uptake and biodegradation. Indeed, anti-Colony Stimulating Factor 1 Receptor (CSF1R)-mediated depletion of KCs resulted in elevated serum iron levels and impaired iron uptake by the liver. Gene expression profiling indicated that C-C chemokine receptor type 5 (CCR5) might be involved in monocyte recruitment to the liver, confirmed by pharmaceutical inhibition of CCR5. Liver KCs play a pivotal role in the clearance and storage of IV iron and KCs appear to be supported by the expanded blood monocyte population.


Asunto(s)
Macrófagos del Hígado , Nanopartículas , Animales , Carbohidratos , Hierro/metabolismo , Macrófagos del Hígado/metabolismo , Hígado/metabolismo , Ratones , Monocitos/metabolismo
17.
Allergy ; 77(1): 243-257, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34496033

RESUMEN

BACKGROUND: 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, has greatly added to our ability to keep the virus at bay; again, however, 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℃. METHODS: Here, we describe such a vaccine candidate, consisting of the SARS-CoV-2 receptor-binding motif (RBM) grafted genetically onto the surface of the immunologically optimized cucumber mosaic virus, called CuMVTT -RBM. RESULTS: Using bacterial fermentation and continuous flow centrifugation for purification, the yield of the production process is estimated to be >2.5 million doses per 1000-litre fermenter run. We demonstrate that the candidate vaccine is highly immunogenic in mice and rabbits and induces more high avidity antibodies compared to convalescent human sera. The induced antibodies are more cross-reactive to mutant RBDs of variants of concern (VoC). Furthermore, antibody responses are neutralizing and long-lived. In addition, the vaccine candidate was stable for at least 14 months at 4℃. CONCLUSION: Thus, the here presented VLP-based vaccine may be a good candidate for use as conventional vaccine in the long term.


Asunto(s)
COVID-19 , Vacunas de Partículas Similares a Virus , Animales , Anticuerpos Neutralizantes , Formación de Anticuerpos , Vacunas contra la COVID-19 , Control de Enfermedades Transmisibles , Humanos , Ratones , Conejos , SARS-CoV-2
18.
Behav Res Methods ; 54(4): 1954-1975, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34799842

RESUMEN

Language production experiments with overt articulation have thus far only scarcely been conducted online, mostly due to technical difficulties related to measuring voice onset latencies. Especially the poor audiovisual synchrony in web experiments (Bridges et al. 2020) is a challenge to time-locking stimuli and participants' spoken responses. We tested the viability of conducting language production experiments with overt articulation in online settings using the picture-word interference paradigm - a classic task in language production research. In three pre-registered experiments (N = 48 each), participants named object pictures while ignoring visually superimposed distractor words. We implemented a custom voice recording option in two different web experiment builders and recorded naming responses in audio files. From these stimulus-locked audio files, we extracted voice onset latencies offline. In a control task, participants classified the last letter of a picture name as a vowel or consonant via button-press, a task that shows comparable semantic interference effects. We expected slower responses when picture and distractor word were semantically related compared to unrelated, independently of task. This semantic interference effect is robust, but relatively small. It should therefore crucially depend on precise timing. We replicated this effect in an online setting, both for button-press and overt naming responses, providing a proof of concept that naming latency - a key dependent variable in language production research - can be reliably measured in online experiments. We discuss challenges for online language production research and suggestions of how to overcome them. The scripts for the online implementation are made available.


Asunto(s)
Lenguaje , Reconocimiento Visual de Modelos , Atención/fisiología , Humanos , Internet , Reconocimiento Visual de Modelos/fisiología , Semántica
19.
Vaccines (Basel) ; 9(11)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34835247

RESUMEN

Type 2 Diabetes Mellitus (T2DM) is a chronic progressive disease, defined by insulin resistance and insufficient insulin secretion to maintain normoglycemia. Amyloidogenic aggregates are a hallmark of T2DM patients; they are cytotoxic for the insulin producing ß-cells, and cause inflammasome-dependent secretion of IL-1ß. To avoid the associated ß-cell loss and inflammation in advanced stage T2DM, we developed a novel monoclonal therapy targeting the major component of aggregates, islet amyloid polypeptide (IAPP). The here described monoclonal antibody (mAb) m81, specific for oligomeric and fibrils, but not for soluble free IAPP, is able to prevent oligomer growth and aggregate formation in vitro, and blocks islet inflammation and disease progression in vivo. Collectively, our data show that blocking fibril formation and prevention of new amyloidogenic aggregates by monoclonal antibody therapy may be a potential therapy for T2DM.

20.
J Psycholinguist Res ; 50(6): 1437-1459, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34674141

RESUMEN

In experiments investigating the processing of true and false negative sentences, it is often reported that polarity interacts with truth-value, in the sense that true sentences lead to faster reaction times than false sentences in affirmative conditions whereas the same does not hold for negative sentences. Various reasons for this difference between affirmative and negative sentences have been discussed in the literature (e.g., lexical associations, predictability, ease of comparing sentence and world). In the present study, we excluded lexical associations as a potential influencing factor. Participants saw artificial visual worlds (e.g., a white square and a black circle) and corresponding sentences (i.e., "The square/circle is (not) white"). The results showed a clear effect of truth-value for affirmative sentences (true faster than false) but not for negative sentences. This result implies that the well-known truth-value-by-polarity interaction cannot solely be due to long-term lexical associations. Additional predictability manipulations allowed us to also rule out an explanatory account that attributes the missing truth-value effect for negative sentences to low predictability. We also discuss the viability of an informativeness account.


Asunto(s)
Comprensión , Juicio , Humanos , Lenguaje , Tiempo de Reacción
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