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1.
J Infect Dev Ctries ; 18(5): 770-778, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38865403

RESUMO

INTRODUCTION: Studies in different populations have shown that single-nucleotide polymorphisms (SNPs) of tumor necrosis factor-alpha (TNFα) and TNF receptors 1 and 2 (TNFR1 and TNFR2) may be involved in the pathogenesis of lepromatous leprosy (LL). To further explore the results in a Mexican population, we compared the frequencies of the polymorphisms in - 308 G>A TNFA (rs1800629), - 383 A>C TNFRS1A (rs2234649), and + 196 T >G TNFSR1B (rs1061622) genes in LL patients (n = 133) and healthy subjects (n = 198). METHODOLOGY: The genotyping was performed with the polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) technique. Statistical analysis was performed using the χ2 test, within the 95% confidence interval. Odds ratios (OR) were calculated and Hardy-Weinberg equilibrium was verified for all control subjects and patients. RESULTS: We found an association between the TNFSR1 -383 A>C genotype and the risk of lepromatous leprosy when leprosy patients were compared to controls (OR = 1.71, CI: 1.08-2.69, p = 0.02). Furthermore, it was also associated with the risk of LL in a dominant model (AC + CC vs AA, OR: 1.65, 95% CI: 1.05-2.057, p = 0.02). Similar genotype and allele frequencies for the SNPs TNFA - 308 G>A and TNFSR2 + 196 T>G were observed between leprosy patients and healthy subjects. CONCLUSIONS: The TNFSR1 -383 A>C could be a potential marker for the identification of high-risk populations. However, additional studies, using larger samples of different ethnic populations, are required.


Assuntos
Predisposição Genética para Doença , Hanseníase Virchowiana , Polimorfismo de Nucleotídeo Único , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa , Humanos , México , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Hanseníase Virchowiana/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/genética , Receptores Tipo II do Fator de Necrose Tumoral/genética , Adulto Jovem , Idoso , Frequência do Gene , Polimorfismo de Fragmento de Restrição , Estudos de Casos e Controles , Genótipo , Adolescente , Reação em Cadeia da Polimerase
3.
J Infect Dis ; 229(6): 1702-1710, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38213276

RESUMO

Definitive data demonstrating the utility of coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) for treating immunocompromised patients remains elusive. To better understand the mechanism of action of CCP, we studied viral replication and disease progression in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected hamsters treated with CCP obtained from recovered COVID-19 patients that were also vaccinated with an mRNA vaccine, hereafter referred to as Vaxplas. Vaxplas transiently enhanced disease severity and lung pathology in hamsters treated near peak viral replication due to immune complex and activated complement deposition in pulmonary endothelium, and recruitment of M1 proinflammatory macrophages into the lung parenchyma. However, aside from one report, transient enhanced disease has not been reported in CCP recipient patients, and the transient enhanced disease in Vaxplas hamsters may have been due to mismatched species IgG-FcR interactions, infusion timing, or other experimental factors. Despite transient disease enhancement, Vaxplas dramatically reduced virus replication in lungs and improved infection outcome in SARS-CoV-2-infected hamsters.


Assuntos
Anticorpos Antivirais , Soroterapia para COVID-19 , Vacinas contra COVID-19 , COVID-19 , Imunização Passiva , Pulmão , SARS-CoV-2 , Replicação Viral , Animais , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Cricetinae , Pulmão/virologia , Pulmão/imunologia , Pulmão/patologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Humanos , Mesocricetus , Modelos Animais de Doenças , Masculino , Feminino
4.
Artigo em Inglês | MEDLINE | ID: mdl-38134234

RESUMO

OBJECTIVES: Global cognitive changes in older age affect driving behavior and road safety, but how spatial orientation differences affect driving behaviors is unknown on a population level, despite clear implications for driving policy and evaluation during aging. The present study aimed to establish how spatial navigation changes affect driving behavior and road safety within a large cohort of older adults. METHODS: Eight hundred and four participants (mean age: 71.05) were recruited for a prospective cohort study. Participants self-reported driving behavior followed by spatial orientation (allocentric and egocentric) testing and a broader online cognitive battery (visuomotor speed, processing speed, executive functioning, spatial working memory, episodic memory, visuospatial functioning). RESULTS: Spatial orientation performance significantly predicted driving difficulty and frequency. Experiencing more driving difficulty was associated with worse allocentric spatial orientation, processing speed, and source memory performance. Similarly, avoiding challenging driving situations was associated with worse spatial orientation and episodic memory. Allocentric spatial orientation was the only cognitive domain consistently affecting driving behavior in under 70 and over 70 age groups, a common age threshold for driving evaluation in older age. DISCUSSION: We established for the first time that worse spatial orientation performance predicted increased driving difficulty and avoidance of challenging situations within an older adult cohort. Deficits in spatial orientation emerge as a robust indicator of driving performance in older age, which should be considered in future aging driving assessments, as it has clear relevance for road safety within the aging population.


Assuntos
Condução de Veículo , Envelhecimento Saudável , Humanos , Idoso , Orientação Espacial , Estudos Prospectivos , Cognição , Envelhecimento/psicologia
5.
Microorganisms ; 11(12)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38138057

RESUMO

The ability of epithelial barriers to perform as the first defense line against external damage derives from tight junctions, protein complexes that block microorganisms through the paracellular space. Indeed, disturbances of barrier permeability caused by bacterial metabolites and other inflammatory stimuli are the consequence of changes in protein expression in these complexes. Postbiotics, molecules derived from bacteria with beneficial effects on the host, improve barrier function through the activation of survival pathways in epithelial cells. Lacticaseibacillus rhamnosus GG secretes the muramidase p40, which protects intestinal barriers through an EGFR-dependent pathway. In this work, we cloned, expressed, and purified the recombinant p40 protein from L. rhamnosus GR-1 to evaluate its effect on cell viability, cell cytotoxicity, TEER, and protein levels of tight junctions, as well as EGFR activation via Western blot on HaCaT keratinocytes subjected to LPS. We found a novel mutation at residue 368 that does not change the structure of p40. Our protein also reduces the LPS-induced increase in cell cytotoxicity when it is added prior to this stimulus. Furthermore, although LPS did not cause changes in barrier function, p40 increased TEER and occludin expression in HaCaT, but unlike previous work with p40 from LGG, we found that recombinant p40 did not activate EGFR. This suggests that recombinant p40 enhances epithelial barrier function through distinct signaling pathways.

7.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685966

RESUMO

Neutrophil extracellular traps (NETs) require reactive oxygen species (ROS) to eliminate pathogens by inducing oxidative stress. However, this process can also cause tissue damage to the host. Neutrophils contain high concentrations of vitamin C (1.5 mM) compared to the bloodstream (0.1 mM), and this antioxidant can interact with vitamin E and glutathione (GSH) inside the cell to maintain the redox balance. Previous studies have investigated the effect of vitamins E or C and N-acetyl cysteine (NAC) on NET formation, but the interactions of these molecules in neutrophils remain unknown. In this study, we investigated the effect of antioxidants alone and two combinations on NET formation and oxidative stress. Neutrophils were pre-loaded with GSH + NAC or vitamin E + vitamin C + GSH + NAC (termed ALL), and LPS-induced NET formation was assessed using fluorometry and immunofluorescence. Antioxidant effects were evaluated by measuring the total antioxidant capacity (TAC), GSH/GSSG ratio, ROS production, nitrite + nitrate levels, and lipid peroxidation. Our results showed that even low doses of antioxidants are capable of decreasing NETs. Furthermore, the combinations augmented TAC and GSH/GSSG ratio and decreased ROS, nitrites + nitrates, and malondialdehyde (MDA) levels in supplemented neutrophils in vitro.


Assuntos
Antioxidantes , Vitamina E , Cavalos , Animais , Antioxidantes/farmacologia , Vitamina E/farmacologia , Acetilcisteína/farmacologia , Lipopolissacarídeos/farmacologia , Dissulfeto de Glutationa , Espécies Reativas de Oxigênio , Glutationa , Ácido Ascórbico/farmacologia , Vitaminas , Suplementos Nutricionais
8.
bioRxiv ; 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37662344

RESUMO

The utility of COVID-19 convalescent plasma (CCP) for treatment of immunocompromised patients who are not able to mount a protective antibody response against SARS-CoV-2 and who have contraindications or adverse effects from currently available antivirals remains unclear. To better understand the mechanism of protection in CCP, we studied viral replication and disease progression in SARS-CoV-2 infected hamsters treated with CCP plasma obtained from recovered COVID patients that had also been vaccinated with an mRNA vaccine, hereafter referred to as Vaxplas. We found that Vaxplas dramatically reduced virus replication in the lungs and improved infection outcome in SARS-CoV-2 infected hamsters. However, we also found that Vaxplas transiently enhanced disease severity and lung pathology in treated animals likely due to the deposition of immune complexes, activation of complement and recruitment of increased numbers of macrophages with an M1 proinflammatory phenotype into the lung parenchyma.

9.
bioRxiv ; 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37425802

RESUMO

With the SARS-CoV-2 virus still circulating and evolving, there remains an outstanding question if variant-specific vaccines represent the optimal path forward, or if other strategies might be more efficacious towards providing broad protection against emerging variants. Here, we examine the efficacy of strain-specific variants of our previously reported, pan-sarbecovirus vaccine candidate, DCFHP-alum, a ferritin nanoparticle functionalized with an engineered form of the SARS-CoV-2 spike protein. In non-human primates, DCFHP-alum elicits neutralizing antibodies against all known VOCs that have emerged to date and SARS-CoV-1. During development of the DCFHP antigen, we investigated the incorporation of strain-specific mutations from the major VOCs that had emerged to date: D614G, Epsilon, Alpha, Beta, and Gamma. Here, we report the biochemical and immunological characterizations that led us to choose the ancestral Wuhan-1 sequence as the basis for the final DCFHP antigen design. Specifically, we show by size exclusion chromatography and differential scanning fluorimetry that mutations in the VOCs adversely alter the antigen's structure and stability. More importantly, we determined that DCFHP without strain-specific mutations elicits the most robust, cross-reactive response in both pseudovirus and live virus neutralization assays. Our data suggest potential limitations to the variant-chasing approach in the development of protein nanoparticle vaccines, but also have implications for other approaches including mRNA-based vaccines.

11.
Mol Cancer Res ; 21(9): 958-974, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37314749

RESUMO

Prostate cancer progression to the lethal metastatic castration-resistant phenotype (mCRPC) is driven by αv integrins and is associated with Golgi disorganization and activation of the ATF6 branch of unfolded protein response (UPR). Overexpression of integrins requires N-acetylglucosaminyltransferase-V (MGAT5)-mediated glycosylation and subsequent cluster formation with Galectin-3 (Gal-3). However, the mechanism underlying this altered glycosylation is missing. For the first time, using HALO analysis of IHC, we found a strong association of integrin αv and Gal-3 at the plasma membrane (PM) in primary prostate cancer and mCRPC samples. We discovered that MGAT5 activation is caused by Golgi fragmentation and mislocalization of its competitor, N-acetylglucosaminyltransferase-III, MGAT3, from Golgi to the endoplasmic reticulum (ER). This was validated in an ethanol-induced model of ER stress, where alcohol treatment in androgen-refractory PC-3 and DU145 cells or alcohol consumption in patient with prostate cancer samples aggravates Golgi scattering, activates MGAT5, and enhances integrin expression at PM. This explains known link between alcohol consumption and prostate cancer mortality. ATF6 depletion significantly blocks UPR and reduces the number of Golgi fragments in both PC-3 and DU145 cells. Inhibition of autophagy by hydroxychloroquine (HCQ) restores compact Golgi, rescues MGAT3 intra-Golgi localization, blocks glycan modification via MGAT5, and abrogates delivery of Gal-3 to the cell surface. Importantly, the loss of Gal-3 leads to reduced integrins at PM and their accelerated internalization. ATF6 depletion and HCQ treatment synergistically decrease integrin αv and Gal-3 expression and temper orthotopic tumor growth and metastasis. IMPLICATIONS: Combined ablation of ATF6 and autophagy can serve as new mCRPC therapeutic.


Assuntos
N-Acetilglucosaminiltransferases , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Integrinas , Integrina alfaV , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Estresse do Retículo Endoplasmático , Autofagia , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo
12.
Nat Commun ; 14(1): 2149, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069151

RESUMO

While the rapid development of COVID-19 vaccines has been a scientific triumph, the need remains for a globally available vaccine that provides longer-lasting immunity against present and future SARS-CoV-2 variants of concern (VOCs). Here, we describe DCFHP, a ferritin-based, protein-nanoparticle vaccine candidate that, when formulated with aluminum hydroxide as the sole adjuvant (DCFHP-alum), elicits potent and durable neutralizing antisera in non-human primates against known VOCs, including Omicron BQ.1, as well as against SARS-CoV-1. Following a booster ~one year after the initial immunization, DCFHP-alum elicits a robust anamnestic response. To enable global accessibility, we generated a cell line that can enable production of thousands of vaccine doses per liter of cell culture and show that DCFHP-alum maintains potency for at least 14 days at temperatures exceeding standard room temperature. DCFHP-alum has potential as a once-yearly (or less frequent) booster vaccine, and as a primary vaccine for pediatric use including in infants.


Assuntos
COVID-19 , Geranium , Nanopartículas , Animais , Humanos , Vacinas contra COVID-19 , Ferritinas , COVID-19/prevenção & controle , SARS-CoV-2 , Soros Imunes , Primatas , Anticorpos Neutralizantes , Anticorpos Antivirais
13.
Case Rep Womens Health ; 37: e00495, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36968551

RESUMO

Objective: To report a case of ovarian torsion during ovarian stimulation prior to trigger followed by laparoscopic detorsion, trigger, and subsequent successful oocyte retrieval, as well as to review outcomes from the cycle. Case Presentation: A 32-year-old woman with a history of recurrent ovarian torsion presented with ovarian torsion during ovarian stimulation for in vitro fertilization prior to trigger injection. She underwent laparoscopic ovarian detorsion followed by trigger and oocyte retrieval.The rate of fertilization and blastocyst conversion of oocytes retrieved from the ovary affected by torsion was lower than from the contralateral ovary. Viable oocytes and an embryo were produced by the affected ovary. Conclusion: Ovarian torsion during ovarian hyperstimulation for in vitro fertilization is a rare occurrence, particularly prior to trigger. Clinicians can consider proceeding with trigger and oocyte retrieval after treating ovarian torsion in appropriately counseled patients.

14.
Immunology ; 168(3): 538-553, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36271832

RESUMO

The NKp30 receptor is one of the three natural cytotoxic receptors reported in NK cells. This receptor is codified by the NCR3 gene, which encodes three isoforms, a consequence of the alternative splicing of exon 4. A greater expression of the three isoforms (A, B, and C), along with low levels of the NKp30 ligand B7H6, has been reported as a positive prognostic factor in different cancer types. Here, in patients with cervical cancer and precursor lesions, we report an altered immune-phenotype, characterized by non-fitness markers, that correlated with increased disease stage, from CIN 1 to FIGO IV. While overall NK cell numbers increased, loss of NKp30+ NK cells, especially in the CD56dim subpopulation, was found. Perforin levels were decreased in these cells. Decreased expression of the NKp30 C isoform and overexpression of soluble B7H6 was found in cervical cancer patients when compared against healthy subjects. PBMCs from healthy subjects downregulated NKp30 isoforms after co-culture with B7H6-expressing tumour cells. Taken together, these findings describe a unique down-modulation or non-fitness status of the immune response in cervical cancer, the understanding of which will be important for the design of novel immunotherapies against this disease.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Perforina/genética , Células Matadoras Naturais , Isoformas de Proteínas/genética , Processamento Alternativo , Receptor 3 Desencadeador da Citotoxicidade Natural/genética
15.
Neurology ; 100(7): e661-e670, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36332985

RESUMO

BACKGROUND AND OBJECTIVES: Internal neurofibromas, including plexiform neurofibromas (PNF), can cause significant morbidity in patients with neurofibromatosis type 1 (NF1). PNF growth is most pronounced in children and young adults, with more rapid growth thought to occur in a subset of PNF termed distinct nodular lesions (DNL). Growth behavior of internal neurofibromas and DNL in older adults is not well documented; yet knowledge thereof is important for patient risk stratification and clinical trial design. The primary objective of this study was to evaluate the long-term growth behavior of internal neurofibromas in adults with NF1. Secondary objectives were to correlate tumor growth behavior with patient-specific, tumor-specific, and patient-reported variables. METHODS: In this prospective cohort study, internal neurofibromas were identified on coronal short TI inversion recovery sequences on baseline and follow-up whole-body MRIs (WBMRIs). Tumor growth and shrinkage were defined as a volume change ≥20%. The association between tumor growth and patient-specific (baseline age, sex, and genotype), tumor-specific (morphology, location, DNL presence on baseline WBMRI, and maximum standardized uptake value on baseline PET imaging), and patient-reported variables (endogenous and exogenous hormone exposure, pain intensity, and quality of life) was assessed using the Spearman correlation coefficient and Kruskal-Wallis test. RESULTS: Of 106 patients with a baseline WBMRI obtained as part of a previous research study, 44 had a follow-up WBMRI. Three additional patients with WBMRIs acquired for clinical care were included, generating 47 adults for this study. The median age during baseline WBMRI was 42 years (range 18-70). The median time between WBMRIs was 10.4 years. Among 324 internal neurofibromas, 62.8% (56% of PNF and 62.1% of DNL) shrank spontaneously without treatment and 17.1% (17.9% of PNF and 13.8% of DNL) grew. Growth patterns were heterogeneous within participants. Patient-specific, tumor-specific, and patient-reported variables (including endogenous and exogenous hormone exposure) were not strong predictors of tumor growth. DISCUSSION: Internal neurofibroma growth behavior in older adults differs fundamentally from that in children and young adults, with most tumors, including DNL, demonstrating spontaneous shrinkage. Better growth models are needed to understand factors that influence tumor growth. These results will inform clinical trial design for internal neurofibromas.


Assuntos
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatose 1 , Criança , Adulto Jovem , Humanos , Idoso , Adolescente , Adulto , Pessoa de Meia-Idade , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico por imagem , Neurofibromatose 1/genética , Seguimentos , Estudos Prospectivos , Qualidade de Vida , Neurofibroma Plexiforme/diagnóstico por imagem , Neurofibroma Plexiforme/patologia , Neurofibroma/diagnóstico por imagem , Imageamento por Ressonância Magnética
16.
Emerg Infect Dis ; 28(12): 2548-2551, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36417997

RESUMO

Nonhuman primates living in proximity to humans increase risks for sylvatic arbovirus transmission. We collected serum samples from nonhuman primates in Hlawga National Park near Yangon, Myanmar, and detected antibodies against chikungunya (33%) and Japanese encephalitis (4%) viruses. Buffer zones between primate and human communities might reduce cross-species arbovirus transmission.


Assuntos
Arbovírus , Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Mianmar/epidemiologia , Febre de Chikungunya/epidemiologia , Primatas
17.
Elife ; 112022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205477

RESUMO

The estrous cycle is regulated by rhythmic endocrine interactions of the nervous and reproductive systems, which coordinate the hormonal and ovulatory functions of the ovary. Folliculogenesis and follicle progression require the orchestrated response of a variety of cell types to allow the maturation of the follicle and its sequela, ovulation, corpus luteum formation, and ovulatory wound repair. Little is known about the cell state dynamics of the ovary during the estrous cycle and the paracrine factors that help coordinate this process. Herein, we used single-cell RNA sequencing to evaluate the transcriptome of >34,000 cells of the adult mouse ovary and describe the transcriptional changes that occur across the normal estrous cycle and other reproductive states to build a comprehensive dynamic atlas of murine ovarian cell types and states.


Assuntos
Ovário , Ovulação , Animais , Ciclo Estral/fisiologia , Feminino , Camundongos , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Pelve
18.
Nat Chem Biol ; 18(11): 1270-1276, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36076082

RESUMO

Omicron and its subvariants have rendered most authorized monoclonal antibody-based treatments for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ineffective, highlighting the need for biologics capable of overcoming SARS-CoV-2 evolution. These mostly ineffective antibodies target variable epitopes. Here we describe broad-spectrum SARS-CoV-2 inhibitors developed by tethering the SARS-CoV-2 receptor, angiotensin-converting enzyme 2 (ACE2), to known non-neutralizing antibodies that target highly conserved epitopes in the viral spike protein. These inhibitors, called receptor-blocking conserved non-neutralizing antibodies (ReconnAbs), potently neutralize all SARS-CoV-2 variants of concern (VOCs), including Omicron. Neutralization potency is lost when the linker joining the binding and inhibitory ReconnAb components is severed. In addition, a bi-functional ReconnAb, made by linking ACE2 to a bi-specific antibody targeting two non-overlapping conserved epitopes, defined here, shows sub-nanomolar neutralizing activity against all VOCs, including Omicron and BA.2. Given their conserved targets and modular nature, ReconnAbs have the potential to act as broad-spectrum therapeutics against SARS-CoV-2 and other emerging pandemic diseases.


Assuntos
Produtos Biológicos , Tratamento Farmacológico da COVID-19 , Humanos , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus/metabolismo , Anticorpos Antivirais/metabolismo , Peptidil Dipeptidase A/metabolismo , Epitopos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico
19.
J Infect Dis ; 226(10): 1688-1698, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36134603

RESUMO

BACKGROUND: As of early 2022, the Omicron variants are the predominant circulating lineages globally. Understanding neutralizing antibody responses against Omicron BA.1 and BA.2 after vaccine breakthrough infections will provide insights into BA.2 infectivity and susceptibility to subsequent reinfection. METHODS: Live virus neutralization assays were used to study immunity against Delta and Omicron BA.1 and BA.2 variants in samples from 86 individuals, 24 unvaccinated (27.9%) and 62 vaccinated (72.1%), who were infected with Delta (n = 42, 48.8%) or BA.1 (n = 44, 51.2%). Among the 62 vaccinated individuals, 39 were unboosted (62.9%), whereas 23 were boosted (37.1%). RESULTS: In unvaccinated infections, neutralizing antibodies (nAbs) against the three variants were weak or undetectable, except against Delta for Delta-infected individuals. Both Delta and BA.1 breakthrough infections resulted in strong nAb responses against ancestral wild-type and Delta lineages, but moderate nAb responses against BA.1 and BA.2, with similar titers between unboosted and boosted individuals. Antibody titers against BA.2 were generally higher than those against BA.1 in breakthrough infections. CONCLUSIONS: These results underscore the decreased immunogenicity of BA.1 compared to BA.2, insufficient neutralizing immunity against BA.2 in unvaccinated individuals, and moderate to strong neutralizing immunity induced against BA.2 in Delta and BA.1 breakthrough infections.


Assuntos
Anticorpos Neutralizantes , Vacinas , Humanos , Anticorpos Antivirais
20.
Microorganisms ; 10(7)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35889147

RESUMO

The gut microbiota (GM) comprises billions of microorganisms in the human gastrointestinal tract. This microbial community exerts numerous physiological functions. Prominent among these functions is the effect on host immunity through the uptake of nutrients that strengthen intestinal cells and cells involved in the immune response. The physiological functions of the GM are not limited to the gut, but bidirectional interactions between the gut microbiota and various extraintestinal organs have been identified. These interactions have been termed interorganic axes by several authors, among which the gut-brain, gut-skin, gut-lung, gut-heart, and gut-metabolism axes stand out. It has been shown that an organism is healthy or in homeostasis when the GM is in balance. However, altered GM or dysbiosis represents a critical factor in the pathogenesis of many local and systemic diseases. Therefore, probiotics intervene in this context, which, according to various published studies, allows balance to be maintained in the GM, leading to an individual's good health.

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