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1.
Nature ; 596(7870): 114-118, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34262174

RESUMO

Pathogenic fungi reside in the intestinal microbiota but rarely cause disease. Little is known about the interactions between fungi and the immune system that promote commensalism. Here we investigate the role of adaptive immunity in promoting mutual interactions between fungi and host. We find that potentially pathogenic Candida species induce and are targeted by intestinal immunoglobulin A (IgA) responses. Focused studies on Candida albicans reveal that the pathogenic hyphal morphotype, which is specialized for adhesion and invasion, is preferentially targeted and suppressed by intestinal IgA responses. IgA from mice and humans directly targets hyphal-enriched cell-surface adhesins. Although typically required for pathogenesis, C. albicans hyphae are less fit for gut colonization1,2 and we show that immune selection against hyphae improves the competitive fitness of C. albicans. C. albicans exacerbates intestinal colitis3 and we demonstrate that hyphae and an IgA-targeted adhesin exacerbate intestinal damage. Finally, using a clinically relevant vaccine to induce an adhesin-specific immune response protects mice from C. albicans-associated damage during colitis. Together, our findings show that adaptive immunity suppresses harmful fungal effectors, with benefits to both C. albicans and its host. Thus, IgA uniquely uncouples colonization from pathogenesis in commensal fungi to promote homeostasis.


Assuntos
Imunidade Adaptativa , Candida albicans/imunologia , Candida albicans/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Simbiose/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Fungos/imunologia , Candida albicans/patogenicidade , Colite/imunologia , Colite/microbiologia , Colite/patologia , Feminino , Vacinas Fúngicas/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Hifas/imunologia , Imunoglobulina A/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
2.
PLoS Pathog ; 19(8): e1011579, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37611070

RESUMO

Fungal invasion of the oral epithelium is central to the pathogenesis of oropharyngeal candidiasis (OPC). Candida albicans invades the oral epithelium by receptor-induced endocytosis but this process is incompletely understood. We found that C. albicans infection of oral epithelial cells induces c-Met to form a multi-protein complex with E-cadherin and the epidermal growth factor receptor (EGFR). E-cadherin is necessary for C. albicans to activate both c-Met and EGFR and to induce the endocytosis of C. albicans. Proteomics analysis revealed that c-Met interacts with C. albicans Hyr1, Als3 and Ssa1. Both Hyr1 and Als3 are required for C. albicans to stimulate c-Met and EGFR in oral epithelial cells in vitro and for full virulence during OPC in mice. Treating mice with small molecule inhibitors of c-Met and EGFR ameliorates OPC, demonstrating the potential therapeutic efficacy of blocking these host receptors for C. albicans.


Assuntos
Candida albicans , Candidíase Bucal , Animais , Camundongos , Membrana Celular , Receptores ErbB , Caderinas , Células Epiteliais
3.
PLoS Biol ; 20(8): e3001762, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35976859

RESUMO

Candida albicans biofilms are a complex multilayer community of cells that are resistant to almost all classes of antifungal drugs. The bottommost layers of biofilms experience nutrient limitation where C. albicans cells are required to respire. We previously reported that a protein Ndu1 is essential for Candida mitochondrial respiration; loss of NDU1 causes inability of C. albicans to grow on alternative carbon sources and triggers early biofilm detachment. Here, we screened a repurposed library of FDA-approved small molecule inhibitors to identify those that prevent NDU1-associated functions. We identified an antihelminthic drug, Niclosamide (NCL), which not only prevented growth on acetate, C. albicans hyphenation and early biofilm growth, but also completely disengaged fully grown biofilms of drug-resistant C. albicans and Candida auris from their growth surface. To overcome the suboptimal solubility and permeability of NCL that is well known to affect its in vivo efficacy, we developed NCL-encapsulated Eudragit EPO (an FDA-approved polymer) nanoparticles (NCL-EPO-NPs) with high niclosamide loading, which also provided long-term stability. The developed NCL-EPO-NPs completely penetrated mature biofilms and attained anti-biofilm activity at low microgram concentrations. NCL-EPO-NPs induced ROS activity in C. albicans and drastically reduced oxygen consumption rate in the fungus, similar to that seen in an NDU1 mutant. NCL-EPO-NPs also significantly abrogated mucocutaneous candidiasis by fluconazole-resistant strains of C. albicans, in mice models of oropharyngeal and vulvovaginal candidiasis. To our knowledge, this is the first study that targets biofilm detachment as a target to get rid of drug-resistant Candida biofilms and uses NPs of an FDA-approved nontoxic drug to improve biofilm penetrability and microbial killing.


Assuntos
Candidíase , Nanopartículas , Animais , Antifúngicos/farmacologia , Biofilmes , Candida , Candida albicans , Candidíase/microbiologia , Fluconazol/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Niclosamida/farmacologia , Niclosamida/uso terapêutico
4.
PLoS Pathog ; 18(7): e1010681, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35797411

RESUMO

During hematogenously disseminated candidiasis, blood borne fungi must invade the endothelial cells that line the blood vessels to infect the deep tissues. Although Candida albicans, which forms hyphae, readily invades endothelial cells, other medically important species of Candida are poorly invasive in standard in vitro assays and have low virulence in immunocompetent mouse models of disseminated infection. Here, we show that Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei can bind to vitronectin and high molecular weight kininogen present in human serum. Acting as bridging molecules, vitronectin and kininogen bind to αv integrins and the globular C1q receptor (gC1qR), inducing human endothelial cells to endocytose the fungus. This mechanism of endothelial cell invasion is poorly supported by mouse endothelial cells but can be restored when mouse endothelial cells are engineered to express human gC1qR or αv integrin. Overall, these data indicate that bridging molecule-mediated endocytosis is a common pathogenic strategy used by many medically important Candida spp. to invade human vascular endothelial cells.


Assuntos
Candidíase , Células Endoteliais , Animais , Candida , Candida albicans , Candidíase/microbiologia , Células Endoteliais/microbiologia , Humanos , Camundongos , Vitronectina
5.
PLoS Biol ; 19(3): e3000957, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33720927

RESUMO

A forward genetic screening approach identified orf19.2500 as a gene controlling Candida albicans biofilm dispersal and biofilm detachment. Three-dimensional (3D) protein modeling and bioinformatics revealed that orf19.2500 is a conserved mitochondrial protein, structurally similar to, but functionally diverged from, the squalene/phytoene synthases family. The C. albicans orf19.2500 is distinguished by 3 evolutionarily acquired stretches of amino acid inserts, absent from all other eukaryotes except a small number of ascomycete fungi. Biochemical assays showed that orf19.2500 is required for the assembly and activity of the NADH ubiquinone oxidoreductase Complex I (CI) of the respiratory electron transport chain (ETC) and was thereby named NDU1. NDU1 is essential for respiration and growth on alternative carbon sources, important for immune evasion, required for virulence in a mouse model of hematogenously disseminated candidiasis, and for potentiating resistance to antifungal drugs. Our study is the first report on a protein that sets the Candida-like fungi phylogenetically apart from all other eukaryotes, based solely on evolutionary "gain" of new amino acid inserts that are also the functional hub of the protein.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/genética , Proteínas Mitocondriais/genética , Candida albicans/crescimento & desenvolvimento , Biologia Computacional/métodos , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/genética , Genes Mitocondriais/genética , Genes Mitocondriais/fisiologia , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Filogenia , Virulência/genética
6.
J Assoc Physicians India ; 71(12): 14-16, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38736048

RESUMO

INTRODUCTION: Vaccination is an important aspect of preventing/decreasing the severity of any viral disease including severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). This disease being very new in the experience of mankind has very little data on the effect of vaccination on the severity of this disease. We conducted this study with the primary objective to assess the severity and clinical outcome of COVID-19 infections among nonvaccinated and vaccinated individuals. MATERIALS AND METHODS: This was a hospital-based retrospective cohort study including all individuals developing microbiologically confirmed COVID-19 over 5 months from February to 31st July 2021. A questionnaire was used to acquire demographic details, history of vaccination with dates, severity of COVID-19 infection, comorbidities, and outcome. Patients found positive microbiologically for SARS-CoV-2 before any dose of its vaccine were considered nonvaccinated, while patients developing SARS-CoV-2 infection even after a single dose or both doses of vaccine were considered "vaccinated." The outcome and mortality among the vaccinated and nonvaccinated patients were evaluated and compared. RESULTS: The study included 2,879 patients, but complete data were obtained only from 1,500 patients. A total of 1,500 patients were analyzed, out of which 880 are male and 620 are female. The severity of the disease was categorized into mild, moderate, and severe in the age-group of <60 years and >60 years with urban (1051, 70.07%) and rural (449, 29.93%) populations. A total number of recovered patients (n = 245), died patients (n = 215) in the age-group of >60 years while the total recovered patients (n = 823) and dead patients (n = 217) in the age-group <60 years with p = 0.001. Total vaccinated patients in the age-group >60 years (n = 204) and not vaccinated (n = 256) while in the age-group of <60 years total vaccinated n = 229 and not vaccinated n = 811. The outcome of disease in the age-group of >60 years in nonvaccinated 50% recovered and 50% died during the course of illness while in the vaccinated 57.3% recoverd and 42% died p-value 0.14, while in the age-group of <60 years recovery in nonvaccinated 77.6% and death in nonvaccinated was 27.32% while in vaccinated patients 82.28% were recovered and 15% died with significant p-value 0.04. Disease outcome was not found significantly associated with a number of doses with p-values of 0.84 and 0.507 in the age-group of >60 years and <60 years, respectively. A total number of 56 patients received Covaxin and 377 patients received Covishield and disease outcome was not found significantly associated with the type of vaccine. CONCLUSION: Vaccination against COVID-19 was significantly effective in terms of hospitalization and disease severity. Vaccinated persons were less among patients with COVID-19 hospitalization and with severe disease progressing to death. These findings indicate vaccination is helpful in reducing the development of severe COVID-19 infection as compared to nonvaccinated status.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Índice de Gravidade de Doença , Centros de Atenção Terciária , Humanos , Masculino , COVID-19/prevenção & controle , COVID-19/epidemiologia , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Vacinação , Idoso , Índia/epidemiologia , SARS-CoV-2 , Adulto Jovem
7.
J Antimicrob Chemother ; 76(10): 2636-2639, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34263306

RESUMO

OBJECTIVES: Liposomal amphotericin B (L-AMB) and isavuconazonium sulphate are commonly used antifungal drugs to treat mucormycosis. However, the efficacy of combination therapy of L-AMB/isavuconazonium sulphate versus monotherapy is unknown. We used an immunosuppressed mouse model of pulmonary mucormycosis to compare the efficacy of L-AMB/isavuconazonium sulphate versus either drug alone. METHODS: Neutropenic mice were intratracheally infected with either Rhizopus delemar or Mucor circinelloides. Treatment with L-AMB, isavuconazonium sulphate, or a combination of both started 8 h post-infection and continued through to Day +4. Placebo mice received vehicle control. Survival to Day +21 and tissue fungal burden (by conidial equivalent using quantitative PCR) on Day +4, served as primary and secondary endpoints, respectively. RESULTS: For mice infected with R. delemar, L-AMB and isavuconazonium sulphate equally prolonged median survival time and enhanced survival versus placebo (an overall survival of 50% for either drug alone, versus 5% for placebo). Importantly, combination treatment resulted in an overall survival of 80%. Both antifungal drugs reduced tissue fungal burden of lungs and brain by ∼1.0-2.0 log versus placebo-treated mice. Treatment with combination therapy resulted in 2.0-3.5 log reduction in fungal burden of either organ versus placebo and 1.0 log reduction versus either drug alone. Similar treatment outcomes were obtained using mice infected with M. circinelloides. CONCLUSIONS: The L-AMB/isavuconazonium sulphate combination demonstrated greater activity versus monotherapy in immunosuppressed mice infected with either of the two most common causes of mucormycosis. These studies warrant further investigation of L-AMB/isavuconazonium sulphate combination therapy as an optimal therapy of human mucormycosis.


Assuntos
Mucormicose , Anfotericina B , Animais , Antifúngicos/uso terapêutico , Camundongos , Mucor , Mucormicose/tratamento farmacológico , Nitrilas , Piridinas , Rhizopus , Triazóis
8.
PLoS Pathog ; 15(8): e1007460, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31381597

RESUMO

Candida auris is an emerging, multi-drug resistant, health care-associated fungal pathogen. Its predominant prevalence in hospitals and nursing homes indicates its ability to adhere to and colonize the skin, or persist in an environment outside the host-a trait unique from other Candida species. Besides being associated globally with life-threatening disseminated infections, C. auris also poses significant clinical challenges due to its ability to adhere to polymeric surfaces and form highly drug-resistant biofilms. Here, we performed bioinformatic studies to identify the presence of adhesin proteins in C. auris, with sequence as well as 3-D structural homologies to the major adhesin/invasin of C. albicans, Als3. Anti-Als3p antibodies generated by vaccinating mice with NDV-3A (a vaccine based on the N-terminus of Als3 protein formulated with alum) recognized C. auris in vitro, blocked its ability to form biofilms and enhanced macrophage-mediated killing of the fungus. Furthermore, NDV-3A vaccination induced significant levels of C. auris cross-reactive humoral and cellular immune responses, and protected immunosuppressed mice from lethal C. auris disseminated infection, compared to the control alum-vaccinated mice. The mechanism of protection is attributed to anti-Als3p antibodies and CD4+ T helper cells activating tissue macrophages. Finally, NDV-3A potentiated the protective efficacy of the antifungal drug micafungin, against C. auris candidemia. Identification of Als3-like adhesins in C. auris makes it a target for immunotherapeutic strategies using NDV-3A, a vaccine with known efficacy against other Candida species and safety as well as efficacy in clinical trials. Considering that C. auris can be resistant to almost all classes of antifungal drugs, such an approach has profound clinical relevance.


Assuntos
Biofilmes/crescimento & desenvolvimento , Linfócitos T CD4-Positivos/imunologia , Candida/imunologia , Candidíase/prevenção & controle , Resistência a Múltiplos Medicamentos/imunologia , Proteínas Fúngicas/imunologia , Vacinas Fúngicas/administração & dosagem , Compostos de Alúmen/química , Animais , Candidíase/imunologia , Candidíase/microbiologia , Camundongos , Camundongos Endogâmicos ICR , Vacinação
9.
J Assoc Physicians India ; 69(11): 11-12, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34781621

RESUMO

Sjogren's syndrome is a chronic slowly progressive autoimmune disease characterized by lymphocytic infiltration of exocrine glands resulting in xerostomia and dry eyes. The syndrome has wide clinical spectrum from organ specific exocrionopathy to systemic manifestation. The disease can present alone or with other autoimmune diseases like RA, SLE, Scleroderma, autoimmune thyroid disease etc. Prevalence of primary Sjogren's is 0.5-1% and of secondary Sjogren's is 5-20%. Renal involvement is rare and can either be tubulointerstial or glomerular. Based on biopsy reports in the available literature, tubulointerstitial nephritis (TIN) is the most common histological abnormality, followed by glomerulonephritis as a distant second.1 Distal Renal tubular Acidosis is the most common manifestation of TIN. We report a case of a 35 year female with acute onset motor weakness (quadriparesis) with hypokalemia with NAGMA with distal RTA. Patient was diagnosed with Secondary Sjogren's and managed accordingly.


Assuntos
Acidose Tubular Renal , Hipopotassemia , Nefrite Intersticial , Síndrome de Sjogren , Acidose Tubular Renal/complicações , Acidose Tubular Renal/diagnóstico , Feminino , Humanos , Hipopotassemia/etiologia , Quadriplegia/etiologia , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico
10.
Artigo em Inglês | MEDLINE | ID: mdl-31818813

RESUMO

There are limited treatment options for immunosuppressed patients with lethal invasive fungal infections due to Fusarium and Scedosporium Manogepix (MGX; APX001A) is a novel antifungal that targets the conserved Gwt1 enzyme required for localization of glycosylphosphatidylinositol-anchored mannoproteins in fungi. We evaluated the in vitro activity of MGX and the efficacy of the prodrug fosmanogepix (APX001) in immunosuppressed murine models of hematogenously disseminated fusariosis and pulmonary scedosporiosis. The MGX minimum effective concentration (MEC) for Scedosporium isolates was 0.03 µg/ml and ranged from 0.015 to 0.03 µg/ml for Fusarium isolates. In the scedosporiosis model, treatment of mice with 78 mg/kg and 104 mg/kg of body weight fosmanogepix, along with 1-aminobenzotriazole (ABT) to enhance the serum half-life of MGX, significantly increased median survival time versus placebo from 7 days to 13 and 11 days, respectively. Furthermore, administration of 104 mg/kg fosmanogepix resulted in an ∼2-log10 reduction in lung, kidney, or brain conidial equivalents/gram tissue (CE). Similarly, in the fusariosis model, 78 mg/kg and 104 mg/kg fosmanogepix plus ABT enhanced median survival time from 7 days to 12 and 10 days, respectively. A 2- to 3-log10 reduction in kidney and brain CE was observed. In both models, reduction in tissue fungal burden was corroborated with histopathological data, with target organs showing reduced or no abscesses in fosmanogepix-treated mice. Survival and tissue clearance were comparable to a clinically relevant high dose of liposomal amphotericin B (10 to 15 mg/kg). Our data support the continued development of fosmanogepix as a first-in-class treatment for infections caused by these rare molds.


Assuntos
Aminopiridinas/farmacologia , Antifúngicos/farmacologia , Fusariose/tratamento farmacológico , Fusarium/efeitos dos fármacos , Hospedeiro Imunocomprometido , Infecções Fúngicas Invasivas/tratamento farmacológico , Isoxazóis/farmacologia , Scedosporium/efeitos dos fármacos , Aminopiridinas/sangue , Aminopiridinas/farmacocinética , Animais , Antifúngicos/sangue , Antifúngicos/farmacocinética , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/microbiologia , Esquema de Medicação , Combinação de Medicamentos , Fusariose/imunologia , Fusariose/microbiologia , Fusariose/mortalidade , Fusarium/crescimento & desenvolvimento , Fusarium/imunologia , Meia-Vida , Humanos , Infecções Fúngicas Invasivas/imunologia , Infecções Fúngicas Invasivas/microbiologia , Infecções Fúngicas Invasivas/mortalidade , Isoxazóis/sangue , Isoxazóis/farmacocinética , Rim/efeitos dos fármacos , Rim/imunologia , Rim/microbiologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Pró-Fármacos , Scedosporium/crescimento & desenvolvimento , Scedosporium/imunologia , Análise de Sobrevida , Triazóis/farmacologia
11.
J Theor Biol ; 504: 110404, 2020 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-32717196

RESUMO

We propose a Hes1-Notch-miR-9 regulatory network and studied the regulating mechanism of miR-9 and Hes1 dynamics driven by Notch. Change in Notch concentration, which serves as a stress signal, can trigger the dynamics of Hes1 and miR-9 at five different states, namely, sTable (2), sustain (1) and mixed (2) states those may correspond to different cellular states. Further, this Notch stress signal introduce time reversal oscillation, which behaves as backward wave, after a certain threshold value of the stress signal and defends the system from moving to apoptosis. We also observe heterogeneous patterns of Hes1, miR-9 and other molecular species in various two dimensional parameter spaces and found that the variability in the patterns is triggered by Hill coefficient and Hes1 stress signal. The phase or bifurcation diagram in time period of oscillation (TN) driven by Notch signal provides all five states, predicts minimum threshold value TNc beyond which tendency to build up backward wave starts and TNc serves as bifurcation point of the system.


Assuntos
MicroRNAs , Receptores Notch , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , MicroRNAs/genética , Receptores Notch/genética , Transdução de Sinais , Fatores de Transcrição HES-1/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-31685475

RESUMO

Galactomannan (GM) detection in biological samples has been shown to predict therapeutic response by azoles and polyenes. In a murine invasive pulmonary aspergillosis model, fosmanogepix or posaconazole treatment resulted in an ∼6- to 7-log reduction in conidial equivalents (CE)/g lung tissue after 96 h versus placebo. Changes in GM levels in BAL fluid and serum mirrored reductions in lung CE, with significant decreases seen after 96 h or 72 h for fosmanogepix or posaconazole, respectively (P < 0.02).


Assuntos
Antifúngicos/uso terapêutico , Biomarcadores/metabolismo , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Aspergilose Pulmonar Invasiva/metabolismo , Mananas/metabolismo , Animais , Aspergilose/tratamento farmacológico , Aspergilose/metabolismo , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/patogenicidade , Galactose/análogos & derivados , Hospedeiro Imunocomprometido , Pulmão/microbiologia , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Triazóis/uso terapêutico
13.
J Virol ; 92(15)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29793957

RESUMO

We developed a method of simultaneous vaccination with DNA and protein resulting in robust and durable cellular and humoral immune responses with efficient dissemination to mucosal sites and protection against simian immunodeficiency virus (SIV) infection. To further optimize the DNA-protein coimmunization regimen, we tested a SIVmac251-based vaccine formulated with either of two Toll-like receptor 4 (TLR4) ligand-based liposomal adjuvant formulations (TLR4 plus TLR7 [TLR4+7] or TLR4 plus QS21 [TLR4+QS21]) in macaques. Although both vaccines induced humoral responses of similar magnitudes, they differed in their functional quality, including broader neutralizing activity and effector functions in the TLR4+7 group. Upon repeated heterologous SIVsmE660 challenge, a trend of delayed viral acquisition was found in vaccinees compared to controls, which reached statistical significance in animals with the TRIM-5α-resistant (TRIM-5α R) allele. Vaccinees were preferentially infected by an SIVsmE660 transmitted/founder virus carrying neutralization-resistant A/K mutations at residues 45 and 47 in Env, demonstrating a strong vaccine-induced sieve effect. In addition, the delay in virus acquisition directly correlated with SIVsmE660-specific neutralizing antibodies. The presence of mucosal V1V2 IgG binding antibodies correlated with a significantly decreased risk of virus acquisition in both TRIM-5α R and TRIM-5α-moderate/sensitive (TRIM-5α M/S) animals, although this vaccine effect was more prominent in animals with the TRIM-5α R allele. These data support the combined contribution of immune responses and genetic background to vaccine efficacy. Humoral responses targeting V2 and SIV-specific T cell responses correlated with viremia control. In conclusion, the combination of DNA and gp120 Env protein vaccine regimens using two different adjuvants induced durable and potent cellular and humoral responses contributing to a lower risk of infection by heterologous SIV challenge.IMPORTANCE An effective AIDS vaccine continues to be of paramount importance for the control of the pandemic, and it has been proven to be an elusive target. Vaccine efficacy trials and macaque challenge studies indicate that protection may be the result of combinations of many parameters. We show that a combination of DNA and protein vaccinations applied at the same time provides rapid and robust cellular and humoral immune responses and evidence for a reduced risk of infection. Vaccine-induced neutralizing antibodies and Env V2-specific antibodies at mucosal sites contribute to the delay of SIVsmE660 acquisition, and genetic makeup (TRIM-5α) affects the effectiveness of the vaccine. These data are important for the design of better vaccines and may also affect other vaccine platforms.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Produtos do Gene env , Imunidade Humoral , Vacinas contra a SAIDS , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Vacinas de DNA , Adjuvantes Imunológicos/farmacologia , Substituição de Aminoácidos , Animais , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Produtos do Gene env/farmacologia , Imunização , Macaca , Mutação de Sentido Incorreto , Vacinas contra a SAIDS/genética , Vacinas contra a SAIDS/imunologia , Vacinas contra a SAIDS/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Vacinas de DNA/farmacologia
14.
Int J Mol Sci ; 18(8)2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28749434

RESUMO

Chronic infection with hepatitis C virus (HCV) afflicts 3% of the world's population and can lead to serious and late-stage liver diseases. Developing a vaccine for HCV is challenging because the correlates of protection are uncertain and traditional vaccine approaches do not work. Studies of natural immunity to HCV in humans have resulted in many enigmas. Human beings are not immunologically naïve because they are continually exposed to various environmental microbes and antigens, creating large populations of memory T cells. Heterologous immunity occurs when this pool of memory T cells cross-react against a new pathogen in an individual. Such heterologous immunity could influence the outcome when an individual is infected by a pathogen. We have recently made an unexpected finding that adenoviruses, a common environmental pathogen and an experimental vaccine vector, can induce robust cross-reactive immune responses against multiple antigens of HCV. Our unique finding of previously uncharacterized heterologous immunity against HCV opens new avenues to understand HCV pathogenesis and develop effective vaccines.


Assuntos
Hepacivirus/imunologia , Imunidade , Adenoviridae/metabolismo , Sequência de Aminoácidos , Animais , Vetores Genéticos/metabolismo , Humanos , Peptídeos/química , Vacinas Virais/imunologia
15.
Zootaxa ; 3795: 126-34, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24870466

RESUMO

Two new species of the subfamily Trypetinae, Acidoxantha galibeedu David & Ramani, sp. nov. (tribe Nitrariomyiini) and Philophylla lachung Singh & David, sp. nov. (tribe Trypetini) are described from India. Acidoxantha totoflava is documented as new record from India. Keys to the species of known Acidoxantha Hendel and Indian Philophylla Rondani are provided.


Assuntos
Biodiversidade , Tephritidae/classificação , Animais , Feminino , Índia , Masculino , Tephritidae/anatomia & histologia
16.
J Phys Chem B ; 128(13): 3258-3272, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38520354

RESUMO

Iron phosphate glasses (IPGs) have been proposed as futuristic materials for nuclear waste immobilization and anode materials for lithium batteries. Recently, many attempts have been made to propose atomistic models of IPGs to explain their properties from an atomistic viewpoint. In this paper, we seek to produce small scale models of IPG that can be handled within the scheme of density functional theory (DFT) to study its electronic structure. The starting models, generated using the Monte Carlo (MC) method, were subsequently annealed using ab initio molecular dynamics (AIMD) to minimize the coordination defects. The geometry of the equilibrated structure was then optimized at 0 K. This hybrid approach (MC + AIMD + DFT optimization) produced good atomistic models of IPG, which can reproduce the experimentally observed band gap, vibrational density of states, magnetic moment of Fe, and mechanical and optical properties. Computationally expensive melt-quench simulation can be avoided using the present approach, allowing the use of DFT for accurate calculations of properties.

17.
J West Afr Coll Surg ; 13(4): 26-33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38449542

RESUMO

Background: Surgical site infection (SSI) is the third most commonly reported nosocomial infection, accounting for 10%-40% of all nosocomial infections and is a major cause of postoperative morbidity. Knowledge of factors related to SSI can help in reducing its incidence and related morbidity, which in many studies is shown to account for 38% of all infections in surgical patients. Lack of extending nosocomial infection surveillance programme and prevention measures in countries like India is viewed as a major challenge for the future. Objectives: The aims of this work were (1) to study the SSI rate in patients undergoing both elective and emergency abdominal surgery and SSI with CDC, and NNIS risk index; and (2) to assess SSI along with body mass index (BMI), glycaemic status, smoking and duration of pre-operative hospital stay of patients. Materials and Methods: In total, 300 patients who underwent elective and emergency abdominal surgery were enrolled in the study as per inclusion and exclusion criteria. SSI with CDC's NNIS risk index were analysed considering BMI, glycaemic status, smoking and duration of pre-operative hospital stay of patients. Results: In total, 300 cases of abdominal surgeries (elective and emergency) were analysed, out of which 60 cases were diagnosed to have SSI as per the criteria. Conclusion: This study demonstrated that there is a significant increase in SSI with increasing NNIS score that is, the greater the NNIS score, the greater the risk of SSI. With an increase in age, BMI, glycaemic index and preoperative hospital stay, the risk of SSI increases. Smoking and associated comorbidities also increase the risk of SSI.

18.
J Fungi (Basel) ; 9(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675924

RESUMO

Candida auris is a multi-drug-resistant fungal pathogen that can survive outside the host and can easily spread and colonize the healthcare environment, medical devices, and human skin. C. auris causes serious life-threatening infections (up to 60% mortality) in immunosuppressed patients staying in such contaminated healthcare facilities. Some isolates of C. auris are resistant to virtually all clinically available antifungal drugs. Therefore, alternative therapeutic approaches are urgently needed. Using in silico protein modeling and analysis, we identified a highly immunogenic and surface-exposed epitope that is conserved between C. albicans hyphal-regulated protein (Cal-Hyr1p) and Hyr1p/Iff-like proteins in C. auris (Cau-HILp). We generated monoclonal antibodies (MAb) against this Cal-Hyr1p epitope, which recognized several clinical isolates of C. auris representing all four clades. An anti-Hyr1p MAb prevented biofilm formation and enhanced opsonophagocytic killing of C. auris by macrophages. When tested for in vivo efficacy, anti-Hyr1p MAb protected 55% of mice against lethal systemic C. auris infection and showed significantly less fungal burden. Our study is highly clinically relevant and provides an effective alternative therapeutic option to treat infections due to MDR C. auris.

19.
Science ; 381(6665): 1461-1467, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37769084

RESUMO

Candida auris is an emerging fungal pathogen responsible for health care-associated outbreaks that arise from persistent surface and skin colonization. We characterized the arsenal of adhesins used by C. auris and discovered an uncharacterized adhesin, Surface Colonization Factor (Scf1), and a conserved adhesin, Iff4109, that are essential for the colonization of inert surfaces and mammalian hosts. SCF1 is apparently specific to C. auris, and its expression mediates adhesion to inert and biological surfaces across isolates from all five clades. Unlike canonical fungal adhesins, which function through hydrophobic interactions, Scf1 relies on exposed cationic residues for surface association. SCF1 is required for C. auris biofilm formation, skin colonization, virulence in systemic infection, and colonization of inserted medical devices.


Assuntos
Candida auris , Candidíase Invasiva , Proteínas Fúngicas , Proteínas dos Microfilamentos , Animais , Humanos , Candida auris/genética , Candida auris/patogenicidade , Virulência , Candidíase Invasiva/microbiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Domínios Proteicos , Interações Hidrofóbicas e Hidrofílicas , Camundongos
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