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1.
PNAS Nexus ; 3(5): pgae185, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38779114

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a common and life-threatening infection that imposes up to 30% mortality even when appropriate therapy is used. Despite in vitro efficacy determined by minimum inhibitory concentration breakpoints, antibiotics often fail to resolve these infections in vivo, resulting in persistent MRSA bacteremia. Recently, several genetic, epigenetic, and proteomic correlates of persistent outcomes have been identified. However, the extent to which single variables or their composite patterns operate as independent predictors of outcome or reflect shared underlying mechanisms of persistence is unknown. To explore this question, we employed a tensor-based integration of host transcriptional and cytokine datasets across a well-characterized cohort of patients with persistent or resolving MRSA bacteremia outcomes. This method yielded high correlative accuracy with outcomes and immunologic signatures united by transcriptomic and cytokine datasets. Results reveal that patients with persistent MRSA bacteremia (PB) exhibit signals of granulocyte dysfunction, suppressed antigen presentation, and deviated lymphocyte polarization. In contrast, patients with resolving bacteremia (RB) heterogeneously exhibit correlates of robust antigen-presenting cell trafficking and enhanced neutrophil maturation corresponding to appropriate T lymphocyte polarization and B lymphocyte response. These results suggest that transcriptional and cytokine correlates of PB vs. RB outcomes are complex and may not be disclosed by conventional modeling. In this respect, a tensor-based integration approach may help to reveal consensus molecular and cellular mechanisms and their biological interpretation.

2.
Am J Transplant ; 24(3): 406-418, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38379280

RESUMO

HLA donor-specific antibodies (DSA) elicit alloimmune responses against the graft vasculature, leading to endothelial cell (EC) activation and monocyte infiltration during antibody-mediated rejection (AMR). AMR promotes chronic inflammation and remodeling, leading to thickening of the arterial intima termed transplant vasculopathy or cardiac allograft vasculopathy (CAV) in heart transplants. Intragraft-recipient macrophages serve as a diagnostic marker in AMR; however, their polarization and function remain unclear. In this study, we utilized an in vitro Transwell coculture system to explore the mechanisms of monocyte-to-macrophage polarization induced by HLA I DSA-activated ECs. Anti-HLA I (IgG or F(ab')2) antibody-activated ECs induced the polarization of M2 macrophages with increased CD206 expression and MMP9 secretion. However, inhibition of TLR4 signaling or PSGL-1-P-selectin interactions significantly decreased both CD206 and MMP9. Monocyte adherence to Fc-P-selectin coated plates induced M2 macrophages with increased CD206 and MMP9. Moreover, Fc-receptor and IgG interactions synergistically enhanced active-MMP9 in conjunction with P-selectin. Transcriptomic analysis of arteries from DSA+CAV+ rejected cardiac allografts and multiplex-immunofluorescent staining illustrated the expression of CD68+CD206+CD163+MMP9+ M2 macrophages within the neointima of CAV-affected lesions. These findings reveal a novel mechanism linking HLA I antibody-activated endothelium to the generation of M2 macrophages which secrete vascular remodeling proteins contributing to AMR and CAV pathogenesis.


Assuntos
Receptor 4 Toll-Like , Doenças Vasculares , Humanos , Metaloproteinase 9 da Matriz , Selectina-P , Macrófagos , Endotélio , Antígenos HLA , Aloenxertos , Imunoglobulina G
3.
Bioorg Chem ; 144: 107159, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309001

RESUMO

Misfolding/aggregation of ß-amyloid peptide lead to the formation of toxic oligomers or accumulation of amyloid plaques, which is a seminal step in the progression of Alzheimer's disease (AD). Despite continuous efforts in the development of therapeutic agents, the cure for AD remains a major challenge. Owing to specific binding affinity of structure-based peptides, we report the synthesis of new peptide-based inhibitors derived from the C-terminal sequences, Aß38-40 and Aß40-42. Preliminary screening using MTT cell viability assay and corroborative results from ThT fluorescence assay revealed a tripeptide showing significantly effective inhibition towards Aß1-42 aggregation and induced toxicity. Peptide 3 exhibited excellent cell viability of 94.3 % at 2 µM and of 100 % at 4 µM and 10 µM. CD study showed that peptide 3 restrict the conformation transition of Aß1-42 peptide towards cross-ß-sheet structure and electron microscopy validated the absence of Aß aggregates as indicated by the altered morphology of Aß1-42 in the presence of peptide 3. The HRMS-ESI, DLS and ANS studies were performed to gain mechanistic insights into the effect of inhibitor against Aß aggregation. This Aß-derived ultrashort motif provides impetus for the development of peptide-based anti-AD agents.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Sobrevivência Celular
4.
Water Air Soil Pollut ; 234(6): 349, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275322

RESUMO

Water pollution is a global issue as a consequence of rapid industrialization and urbanization. Organic compounds which are generated from various industries produce problematic pollutants in water. Recently, metal oxide (TiO2, SnO2, CeO2, ZrO2, WO3, and ZnO)-based semiconductors have been explored as excellent photocatalysts in order to degrade organic pollutants in wastewater. However, their photocatalytic performance is limited due to their high band gap (UV range) and recombination time of photogenerated electron-hole pairs. Strategies for improving the performance of these metal oxides in the fields of photocatalysis are discussed. To improve their photocatalytic activity, researchers have investigated the concept of doping, formation of nanocomposites and core-shell nanostructures of metal oxides. Rare-earth doped metal oxides have the advantage of interacting with functional groups quickly because of the 4f empty orbitals. More precisely, in this review, in-depth procedures for synthesizing rare earth doped metal oxides and nonocomposites, their efficiency towards organic pollutants degradation and sources have been discussed. The major goal of this review article is to propose high-performing, cost-effective combined tactics with prospective benefits for future industrial applications solutions.

5.
PLoS One ; 18(5): e0285870, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205661

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection, either de novo or as reactivation after allotransplantation and chronic immunosuppression, is recognized to cause detrimental alloimmune effects, inclusive of higher susceptibility to graft rejection and substantive impact on chronic graft injury and reduced transplant survival. To obtain further insights into the evolution and pathogenesis of CMV infection in an immunocompromised host we evaluated changes in the circulating host proteome serially, before and after transplantation, and during and after CMV DNA replication (DNAemia), as measured by quantitative polymerase chain reaction (QPCR). METHODS: LC-MS-based proteomics was conducted on 168 serially banked plasma samples, from 62 propensity score-matched kidney transplant recipients. Patients were stratified by CMV replication status into 31 with CMV DNAemia and 31 without CMV DNAemia. Patients had blood samples drawn at protocol times of 3- and 12-months post-transplant. Additionally, blood samples were also drawn before and 1 week and 1 month after detection of CMV DNAemia. Plasma proteins were analyzed using an LCMS 8060 triple quadrupole mass spectrometer. Further, public transcriptomic data on time matched PBMCs samples from the same patients was utilized to evaluate integrative pathways. Data analysis was conducted using R and Limma. RESULTS: Samples were segregated based on their proteomic profiles with respect to their CMV Dnaemia status. A subset of 17 plasma proteins was observed to predict the onset of CMV at 3 months post-transplant enriching platelet degranulation (FDR, 4.83E-06), acute inflammatory response (FDR, 0.0018), blood coagulation (FDR, 0.0018) pathways. An increase in many immune complex proteins were observed at CMV infection. Prior to DNAemia the plasma proteome showed changes in the anti-inflammatory adipokine vaspin (SERPINA12), copper binding protein ceruloplasmin (CP), complement activation (FDR = 0.03), and proteins enriched in the humoral (FDR = 0.01) and innate immune responses (FDR = 0.01). CONCLUSION: Plasma proteomic and transcriptional perturbations impacting humoral and innate immune pathways are observed during CMV infection and provide biomarkers for CMV disease prediction and resolution. Further studies to understand the clinical impact of these pathways can help in the formulation of different types and duration of anti-viral therapies for the management of CMV infection in the immunocompromised host.


Assuntos
Infecções por Citomegalovirus , Transplante de Rim , Serpinas , Humanos , Transplante de Rim/efeitos adversos , Citomegalovirus/genética , Proteoma , Proteômica , DNA Viral/genética
6.
Immunobiology ; 228(3): 152354, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36854249

RESUMO

The significance of self-peptide-MHC-I/TCR (SMT) interaction in the survival of CD8+ T cells during naïve- and developmental-stages is well documented. However, the same for the memory stage is contentious. Previous studies have attempted to address the issue using MHC-I or TCR deficient systems, but inconsistent findings with memory CD8+ T cells of different TCR specificities have complicated the interpretation. Differential presence and/or processing of TCR-signals downstream in memory CD8+ T cells of different TCR specificities could be thought of as a reason. In this study, we examined the TCR-signals downstream in memory CD8+ T cells and compared them to the presence of survival-related signals (Annexin-V, Bcl-2, and Ki-67). We categorically tracked foreign antigen-experienced memory CD8+ T (TM) cells generated after Plasmodium pre-erythrocytic-stage malaria infection in C57BL/6 mice. Interestingly, we found that memory CD8+ T cells had more TCR-signals downstream than naive cells. We reasoned and attributed the increased expression of cell adhesion molecules to the enhanced TCR-signaling. TCR-signals downstream correlate more closely with survival signals in naive CD8+ T cells than with death signals in TM cells. Further investigation using antigen-specific CD8+ T cells and diverse infection systems would aid in conceptualizing the findings.


Assuntos
Linfócitos T CD8-Positivos , Receptores de Antígenos de Linfócitos T , Camundongos , Animais , Receptores de Antígenos de Linfócitos T/metabolismo , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Antígenos/metabolismo , Homeostase , Camundongos Transgênicos
7.
Med Res Rev ; 43(4): 775-828, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36710510

RESUMO

Modified and synthetic α-amino acids are known to show diverse applications. Histidine, which possesses numerous applications when subjected to synthetic modifications, is one such amino acid. The utility of modified histidines varies widely from remarkable biological activities to catalysis, and from nanotechnology to polymer chemistry. This renders histidine residue an important place in scientific research. Histidine is a well-studied scaffold and constitutes the active site of various enzymes catalyzing important reactions in the biological systems. A rational modification in histidine structure with a distinctly developed protocol extensively changes its physical and chemical properties. The utilization of modified histidines in search of potent, target selective and proteostable scaffolds is vital in the development of bioactive peptides with enhanced drug-likeliness. This review is a compilation and analysis of reported side-chain ring modifications at histidine followed by applications of ring-modified histidines in the synthesis of various categories of bioactive peptides and peptidomimetics.


Assuntos
Química Farmacêutica , Histidina , Humanos , Histidina/química , Peptídeos/farmacologia , Peptídeos/química , Descoberta de Drogas
8.
Microbiol Immunol ; 66(2): 41-51, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34674290

RESUMO

Radiation attenuated sporozoite (RAS), a whole-parasite vaccine approach, provides sterile protection against malaria. However, RAS immunization does not confer protection for long, and that has been correlated with the waning parasite-induced memory CD8+ T-cell responses. Interestingly, an intermittent infectious (wild type) sporozoite challenge to the RAS-vaccinated mice lengthened the protection period from 6 to 18 months. Herein, we have studied the changes induced by the infectious sporozoites in RAS-induced memory CD8+ T cells for conferring lengthened protection. We observed that the infectious sporozoite challenge boosted the frequency of foreign antigen-experienced memory CD8+ T cells. In those CD8+ T cells, it has reduced the Annexin-V reactivity, raised Bcl-2 expression, and also more cells undergo homeostatic proliferation (Ki-67+ ). It has also scaled down the frequency of Nur77 and CX3CR1 high expressing cells in those memory CD8+ T-cell populations which we further correlated with better survival signals.


Assuntos
Esporozoítos , Vacinas , Animais , Linfócitos T CD8-Positivos , Memória Imunológica , Fígado , Camundongos , Plasmodium berghei
9.
JCI Insight ; 6(21)2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34609965

RESUMO

CMV causes mostly asymptomatic but lifelong infection. Primary infection or reactivation in immunocompromised individuals can be life-threatening. CMV viremia often occurs in solid organ transplant recipients and associates with decreased graft survival and higher mortality. Furthering understanding of impaired immunity that allows CMV reactivation is critical to guiding antiviral therapy and examining the effect of CMV on solid organ transplant outcomes. This study characterized longitudinal immune responses to CMV in 31 kidney transplant recipients with CMV viremia and matched, nonviremic recipients. Recipients were sampled 3 and 12 months after transplant, with additional samples 1 week and 1 month after viremia. PBMCs were stained for NK and T cell markers. PBMC transcriptomes were characterized by RNA-Seq. Plasma proteins were quantified by Luminex. CD8+ T cell transcriptomes were characterized by single-cell RNA-Seq. Before viremia, patients had high levels of IL-15 with concurrent expansion of immature CD56bright NK cells. After viremia, mature CD56dim NK cells and CD28-CD8+ T cells upregulating inhibitory and NK-associated receptors were expanded. Memory NK cells and NK-like CD28-CD8+ T cells were associated with control of viremia. These findings suggest that signatures of innate activation may be prognostic for CMV reactivation after transplant, while CD8+ T cell functionality is critical for effective control of CMV.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/etiologia , Transplante de Rim/efeitos adversos , Células Matadoras Naturais/imunologia , Viremia/imunologia , Adulto , Idoso , Infecções por Citomegalovirus/fisiopatologia , Feminino , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
10.
Parasite Immunol ; 41(7): e12622, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30854655

RESUMO

Immunization with radiation-attenuated Plasmodium sporozoites (RAS) induces sterile and long-lasting protective immunity. Although intravenous (IV) route of RAS immunization is reported to induce superior immunity compared to intradermal (ID) injection, its role in the maintenance of sterile immunity is yet to be understood. We investigated whether the route of homologous sporozoite challenge of Plasmodium berghei (Pb) RAS-immunized mice would influence the longevity of protection. C57BL/6 mice immunized with Pb-RAS by IV were 100% protected upon primary IV/ID sporozoite challenge. In contrast, ID immunization resulted in 80% protection, regardless of primary challenge route. Interestingly, the route of primary challenge was found to bring difference in the maintenance of sterile protection. While IV Pb RAS-immunized mice remained protected at all challenges regardless of the route of primary challenge, ID Pb-RAS-immunized mice receiving ID primary challenge became parasitaemic upon secondary IV challenge. Significantly, primary IV challenge of Pb RAS ID-immunized mice resulted in 80% and 50% survival at secondary and tertiary challenges, respectively. According to phenotypically diverse liver CD8+ T cells, the percentages and the numbers of both CD8+ T effector memory and resident memory cells were significantly higher in IV than in ID Pb RAS-immunized mice. IFN-γ-producing CD8+ T cells specific to Pb TRAP130 and MIP-4-Kb-17 were also found significantly higher in IV mice than in ID mice. The enhanced T-cell generation and the longevity of protection appear to be dependent on the parasite load during challenge when infection is tolerated under suboptimal CD8+ T-cell response.


Assuntos
Memória Imunológica , Fígado/imunologia , Malária/imunologia , Plasmodium berghei/imunologia , Esporozoítos/imunologia , Administração Intravenosa , Animais , Antígenos de Protozoários/administração & dosagem , Linfócitos T CD8-Positivos/imunologia , Feminino , Imunização , Injeções Intradérmicas , Fígado/parasitologia , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Esporozoítos/efeitos da radiação
11.
Cell Immunol ; 337: 1-14, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30773218

RESUMO

Inducing long-lived memory T cells by sub-unit vaccines has been a challenge. Subunit vaccines containing single immunogenic target antigen from a given pathogen have been designed with the presumption of mimicking the condition associated with natural infection, but fail to induce quality memory responses. In this study, we have included non-target antigens with vaccine candidate, OVA, in the inoculum containing TLR ligands to suffice the minimal condition of pathogen to provoke immune response. We found that inclusion of immunogenic HEL (hen egg lysozyme) or poorly immunogenic MBP (Myelin Basic protein) non-target antigen enhances the OVA specific CD4 T cell responses. Interestingly, poorly immunogenic MBP was found to strongly favor the generation of OVA specific memory CD4 T cells. MBP not only improves magnitude of T cell response but also promotes the T cells to undergo higher cycles of division, one of the characteristic of central memory T cells. Inclusion of MBP with vaccine targets was also found to promote multiple cytokine producing CD4 T cells. We also found that challenge of host with non-target antigen MBP favors generation of central Memory T cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Imunogenicidade da Vacina/imunologia , Memória Imunológica/imunologia , Animais , Formação de Anticorpos , Antígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade Celular/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Muramidase/imunologia , Muramidase/farmacologia , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/farmacologia , Ovalbumina/imunologia , Receptores Toll-Like/imunologia , Vacinação , Vacinas/imunologia
12.
Front Immunol ; 9: 192, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29472929

RESUMO

Immunization with radiation-attenuated sporozoites (RAS) shown to confer complete sterile protection against Plasmodia liver-stage (LS) infection that lasts about 6 to 9 months in mice. We have found that the intermittent infectious sporozoite challenge to immune mice following RAS vaccination extends the longevity of sterile protection by maintaining CD8+ T cell memory responses to LS infection. It is reported that CD8α+ dendritic cells (DCs) are involved in the induction of LS-specific CD8+ T cells following RAS or genetically attenuated parasite (GAP) vaccination. In this study, we demonstrate that CD8α+ DCs respond differently to infectious sporozoite or RAS inoculation. The higher accumulation and activation of CD8α+ DCs was seen in the liver in response to infectious sporozoite 72 h postinoculation and found to be associated with higher expression of chemokines (CCL-20 and CCL-21) and type I interferon response via toll-like receptor signaling in liver. Moreover, the infectious sporozoites were found to induce qualitative changes in terms of the increased MHCII expression as well as costimulatory molecules including CD40 on the CD8α+ DCs compared to RAS inoculation. We have also found that infectious sporozoite challenge increased CD40L-expressing CD4+ T cells, which could help CD8+ T cells in the liver through "licensing" of the antigen-presenting cells. Our results suggest that infectious sporozoite challenge to prior RAS immunized mice modulates the CD8α+ DCs, which might be shaping the fate of memory CD8+ T cells against Plasmodium LS infection.


Assuntos
Antígenos CD8/imunologia , Células Dendríticas/imunologia , Memória Imunológica , Fígado/imunologia , Malária/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Antígenos CD40/genética , Antígenos CD8/genética , Linfócitos T CD8-Positivos/imunologia , Quimiocinas/imunologia , Células Dendríticas/parasitologia , Feminino , Interferon Tipo I/imunologia , Fígado/citologia , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmodium berghei , Esporozoítos/imunologia , Esporozoítos/efeitos da radiação
13.
Virus Res ; 244: 1-5, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29113822

RESUMO

TNF-α has been shown to play an important role in pathogenesis and latency of HSV-1 infections. TNF-α signals through TNFR1 (p55) and TNFR2 (p75), and signaling through p55 generally results in gene activation leading to induction of inflammatory responses. Here, we studied the role of TNF-α signaling in latent virus reactivation in p55-knock out (KO) mouse model of ocular HSV-1 infection. We found that KO mice are more susceptible to HSV-1 infection compared to wild type C57Bl/6 mice. While the absence of TNFRI signaling enhanced the ganglion latent DNA content by two folds, there was no difference in the maintenance and reactivation of latent HSV-1. Strikingly, interfering with inflammatory responses through PGE2 synthesis by treating latently infected wild type mice with indomethacin (COX inhibitor) prior to UV-exposure prevented HSV-1 reactivation. These results suggest that reactivation of latent HSV-1 might result from the cumulative effects of a cascade of inflammatory cytokines including TNF-α.


Assuntos
Herpesvirus Humano 1/imunologia , Interações Hospedeiro-Patógeno , Ceratite Herpética/imunologia , Prostaglandina-Endoperóxido Sintases/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Inibidores de Ciclo-Oxigenase/farmacologia , DNA Viral/genética , DNA Viral/imunologia , Dinoprostona/imunologia , Dinoprostona/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/efeitos da radiação , Indometacina/farmacologia , Ceratite Herpética/genética , Ceratite Herpética/terapia , Ceratite Herpética/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prostaglandina-Endoperóxido Sintases/genética , Receptores Tipo I de Fatores de Necrose Tumoral/deficiência , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Raios Ultravioleta , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação , Latência Viral/efeitos dos fármacos , Latência Viral/efeitos da radiação
14.
Cell Immunol ; 317: 48-54, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28499490

RESUMO

Whole sporozoite vaccine (WSV) is shown to induce sterile protection that targets Plasmodium liver-stage infection. There are many underlying issues associated with induction of effective sterile protracted protection. In this study, we have addressed how the alterations in successive vaccine regimen could possibly affect the induction of sterile protection. We have demonstrated that the pattern of vaccination with RAS (radiation attenuated sporozoites) induces varying degrees of protection among B6 mice. Animals receiving four successive doses generated 100% sterile protection. However, three successive doses, though with the same parasite inoculum as four doses, could induce sterile protection in ∼50% mice. Interestingly, mice immunized with the same 3 doses, but with longer gap, could not survive the challenge. We demonstrate that degree of protection correlates with the frequencies of IFN-γ+ and multifunctional (IFN-γ+ CD107a+) CD8+ TEM cells present in liver. The failure to achieve protective threshold frequency of these cells in liver might make the host more vulnerable to parasite infection during infectious sporozoite challenge.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Interferon gama/metabolismo , Hepatopatias/imunologia , Fígado/imunologia , Vacinas Antimaláricas/imunologia , Malária/imunologia , Plasmodium/imunologia , Animais , Linfócitos T CD8-Positivos/parasitologia , Células Cultivadas , Interações Hospedeiro-Parasita , Humanos , Memória Imunológica , Fígado/parasitologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Radiação , Esporozoítos/imunologia , Vacinação
15.
Colloids Surf B Biointerfaces ; 154: 321-330, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28363192

RESUMO

Current treatment therapeutic approach for tuberculosis is the administration of first line drugs in the form of tablets and capsules for 4-6 months. However, this approach leads to severe adverse effects. Therefore, present study was designed to achieving local and sustained targeting of anti-tubercular drugs in order to reduce dose and frequency. The nanoparticle based dry powder formulation of rifampicin was developed and analyzed with respect to its direct targeting potential of lungs. Rifampicin loaded nanoparticles were formulated by ionic gelation probe sonication method, and characterized with respect to particle size, zeta potential, entrapment and drug loading efficiency. The range of size and entrapment efficiency of prepared nanoparticles was estimated from 124.1±0.2 to 402.3±2.8nm and 72.00±0.1%, respectively. The freeze-dried powder of nanoparticle formulation was used to carry out in vitro lung deposition studies through Andersen cascade impactor. The cumulative in vitro drug release studies with developed nanoparticle formulation showed sustained release up to 24h. Our in vitro sustained drug release results were corroborated by the extended residence and slow clearance of rifampicin from the lungs. Furthermore, our results suggest the minimum lung distribution of drug in treated rats which confirms the negligible toxicity rendered by nanoparticle dry powder formulation. Moreover, pharmacokinetic and toxicity studies carried out with prepared NPs dry powder inhalation (DPI) formulations and compared with conventional DPI.


Assuntos
Antituberculosos/farmacocinética , Quitosana/química , Preparações de Ação Retardada , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas/química , Rifampina/farmacocinética , Administração por Inalação , Animais , Antituberculosos/química , Linhagem Celular , Quitosana/farmacocinética , Liberação Controlada de Fármacos , Inaladores de Pó Seco , Liofilização , Meia-Vida , Pulmão/metabolismo , Macrófagos Alveolares/citologia , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Nanopartículas/administração & dosagem , Tamanho da Partícula , Pós , Ratos , Ratos Wistar , Rifampina/química , Tuberculose Pulmonar/tratamento farmacológico
16.
Sci Rep ; 7: 41083, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198424

RESUMO

Targeting of myeloid-dendritic cell receptor DC-SIGN by numerous chronic infectious agents, including Porphyromonas gingivalis, is shown to drive-differentiation of monocytes into dysfunctional mDCs. These mDCs exhibit alterations of their fine-tuned homeostatic function and contribute to dysregulated immune-responses. Here, we utilize P. gingivalis mutant strains to show that pathogen-differentiated mDCs from primary human-monocytes display anti-apoptotic profile, exhibited by elevated phosphorylated-Foxo1, phosphorylated-Akt1, and decreased Bim-expression. This results in an overall inhibition of DC-apoptosis. Direct stimulation of complex component CD40 on DCs leads to activation of Akt1, suggesting CD40 involvement in anti-apoptotic effects observed. Further, these DCs drove dampened CD8+ T-cell and Th1/Th17 effector-responses while inducing CD25+Foxp3+CD127- Tregs. In vitro Treg induction was mediated by DC expression of indoleamine 2,3-dioxygenase, and was confirmed in IDO-KO mouse model. Pathogen-infected &CMFDA-labeled MoDCs long-lasting survival was confirmed in a huMoDC reconstituted humanized mice. In conclusion, our data implicate PDDCs as an important target for resolution of chronic infection.


Assuntos
Células Dendríticas/imunologia , Porphyromonas gingivalis/patogenicidade , Animais , Apoptose , Proteína 11 Semelhante a Bcl-2/metabolismo , Antígenos CD40/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Proteína Forkhead Box O1/metabolismo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/citologia , Monócitos/metabolismo , Porphyromonas gingivalis/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/citologia , Células Th17/imunologia , Células Th17/metabolismo
17.
Hum Vaccin Immunother ; 13(4): 854-866, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-27901642

RESUMO

The recurrent nasopharyngeal carcinoma of head-and-neck cancers pathology showed unique symptoms and clinical characteristics. The complexity of pathology poses challenges for developing therapeutic interventional approaches against nasopharyngeal carcinoma (NPC). The conventional treatment regimens offer limited local control and survival, which, leads to adverse delayed complications. Our study present a generic monocyte derived dendritic cell (MoDC) vaccine strategy for NPC in which RNA is used as a source of tumor-associated antigens (TAAgs). The RNA extracted from well-characterized highly immunogenic NPC cells (C666-1) was transfected into MoDCs. The formulated and characterized cationic liposomes were used to achieving efficient RNA transfection of immature DCs. Further, DCs were forcibly matured with a cytokine cocktail to achieve greater expression of MHC and co-stimulatory molecules. Moreover, our results did not see any effect of RNA or lipids on MoDCs phenotype or cytokine expression. RNA loaded DCs derived from HLA-A2-positive donors were shown to activate effector memory cytotoxic T lymphocytes (CTLs) specific for TAAg ligand expressed by C666-1 cells. Our results show the comparison of cytotoxic response mounted against RNA-loaded DCs with those directly stimulated by C666-1 tumor cells. Our findings suggest that DCs expressing tumor cell RNA primed naïve T cells show T cells priming with lesser cytotoxicity and cytokine secretion when exposed with with C666-1 tumor cells. These results surface the potential of DCs to deliver RNA in NPCs, sufficient presentation of RNA to provoke perdurable immune responses against nasopharyngeal carcinoma. Our results implies that DC based vaccine approach may be useful to develop therapeutic interventional approach in the form of vaccine to address NPCs.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Imunoterapia/métodos , Neoplasias Nasofaríngeas/terapia , RNA/imunologia , Animais , Antígenos de Neoplasias/genética , Vacinas Anticâncer/administração & dosagem , Carcinoma , Voluntários Saudáveis , Humanos , Ativação Linfocitária , Camundongos Nus , Carcinoma Nasofaríngeo , RNA/genética , Linfócitos T Citotóxicos/imunologia , Transfecção
18.
Vaccine ; 34(28): 3229-34, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27160038

RESUMO

Whole sporozoite vaccine (WSV) approach has been shown to induce efficient CD8(+) T cell response, critical for developing of long-lasting sterile protection against Plasmodium. Although WSV was initiated over four decades ago, we still do not fully understand about the absolute requirements for the generation of liver-stage specific CD8(+) T memory cells. For more than a decade intravenous (IV) route of immunization has been shown to be protective in pre-clinical studies. However, the intradermal (ID) route is preferred over IV route by many researchers as it is perceived to mimic the natural route of parasite delivery through mosquito bite. Various clinical studies have shown that ID route provokes poor protective responses compared to those seen with IV route of administration. The present study highlights the importance of circumsporozoite (CS) protein in preventing sporozoite entry to the hepatocytes, which however, it is not necessarily sufficient to ensure sterile protection. Instead, this article favors the idea that liver-stage development is a prime requirement for generation of antigen specific CD8(+) T cells and suggests the conditions favored by IV inoculation of sporozoite.


Assuntos
Vacinas Antimaláricas/administração & dosagem , Malária/prevenção & controle , Esporozoítos/imunologia , Imunidade Adaptativa , Administração Intravenosa , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Injeções Intradérmicas , Fígado/parasitologia , Vacinas Antimaláricas/uso terapêutico , Plasmodium , Proteínas de Protozoários/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/uso terapêutico
19.
Pharm Methods ; 3(1): 44-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23781477

RESUMO

INTRODUCTION: A simple, rapid, accurate, precise, and economical UV spectrophotometric method for the simultaneous determination of metoprolol succinate (METO) and olmesartan medoxomil (OLME) in a combined tablet dosage form using the simultaneous equation method has been developed. MATERIALS AND METHODS: The method is based on the simultaneous equations for analysis of both the drugs using distilled water as a solvent. METO has absorbance maxima at 221 nm and OLME has absorbance maxima at 257 nm in distilled water. RESULTS: The linearity was obtained in the concentration range of 5-25 µg/ml and 4-20 µg/ml for METO and OLME, respectively. The concentrations of the drugs were determined by using the simultaneous equations method. The mean recovery was 100.90 ± 1.76 and 100.26 ± 0.71 for METO and OLME, respectively. CONCLUSION: The method was found to be simple, accurate, and precise and was applicable for the simultaneous determination of METO and OLME in the pharmaceutical tablet dosage form. The results of analysis have been validated statistically and by recovery studies.

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