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1.
Toxics ; 11(10)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37888715

RESUMO

Benzene, a potent carcinogen, is known to cause acute myeloid leukaemia. While chemotherapy is commonly used for cancer treatment, its side effects have prompted scientists to explore natural products that can mitigate the haematotoxic effects induced by chemicals. One area of interest is nano-theragnostics, which aims to enhance the therapeutic potential of natural products. This study aimed to enhance the effects of methanolic extracts from Ocimum basilicum, Rosemarinus officinalis, and Thymus vulgaris by loading them onto silica nanobeads (SNBs) for targeted delivery to mitigate the benzene-induced haematotoxic effects. The SNBs, 48 nm in diameter, were prepared using a chemical method and were then loaded with the plant extracts. The plant-extract-loaded SNBs were then coated with carboxymethyl cellulose (CMC). The modified SNBs were characterized using various techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-visible spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The developed plant-extract-loaded and CMC-modified SNBs were administered intravenously to benzene-exposed rats, and haematological and histopathological profiling was conducted. Rats exposed to benzene showed increased liver and spleen weight, which was mitigated by the plant-extract-loaded SNBs. The differential white blood cell (WBC) count was higher in rats with benzene-induced haematotoxicity, but this count decreased significantly in rats treated with plant-extract-loaded SNBs. Additionally, blast cells observed in benzene-exposed rats were not found in rats treated with plant-extract-loaded SNBs. The SNBs facilitated targeted drug delivery of the three selected medicinal herbs at low doses. These results suggest that SNBs have promising potential as targeted drug delivery agents to mitigate haematotoxic effects induced by benzene in rats.

2.
Acta Trop ; 248: 107023, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37717686

RESUMO

Millions of people worldwide are affected by cutaneous leishmaniasis (CL), a disease that has a significant impact on morbidity and mortality. Understanding the immune responses responsible for tissue damage or the process of lesion healing plays a pivotal role in shaping optimal treatment strategies. In this study, we investigated immunological phenotypes for three groups: glucantime treated (n = 30) and untreated (n = 30) CL patients infected with Leishmania tropica (L. tropica), and healthy controls (n = 20). T-lymphocytes (CD4+ and CD8+), and B lymphocytes (CD14+ and CD19+) were isolated using antibody-conjugated microbeads and magnetic field isolation to achieve high purity. A higher significant difference was observed between T-lymphocytes (CD4+ and CD8+), and B-lymphocytes (CD14+ and CD19+) cells in CL-infected groups before and after treatment (p < 0.0001). When compared, there was also a significant difference among T-lymphocytes (CD4+ and CD8+), B lymphocytes (CD14+ and CD19+) p < 0.0001, p < 0.0005, and p < 0.0007, respectively between CL-infected individuals (before and after treatment) to controls. Our findings suggest that an increased proportion of these cells seen in treated patients may mediate healing, while it is also possible that they may contribute to tissue injury. Understanding the immune system and lesion size of CL can help develop immunotherapies and comprehend the evolution of this parasitic disease.


Assuntos
Leishmania tropica , Leishmaniose Cutânea , Humanos , Leishmania tropica/genética , Antimoniato de Meglumina/uso terapêutico
3.
Microb Pathog ; 181: 106202, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37327948

RESUMO

Cutaneous Leishmaniasis (CL) affects millions of people globally and has a significant impact on morbidity and mortality. Innate immune mediators are likely to influence the clinical phenotype of CL through primary responses that restrict or facilitate parasite spread. The aim of this preliminary study was to bring to attention the significance of microbiota in the development of CL and emphasized the necessity of including the role of microbiota in CL while promoting a One Health approach for managing diseases. To achieve this, we used 16S amplicon metagenome sequencing and QIIME2 pipeline to analyze the microbiome composition of CL-infected patients compared to non-infected, healthy subjects. 16S sequencing analysis showed serum microbiome was dominated by Firmicutes, Proteobacteria, Bacteroidota, and Actinobacteria. CL-infected individuals, Proteobacteria were the most prevalent (27.63 ± 9.79), with the relative abundance (10.73 ± 5.33) of Proteobacteria in control. Bacilli class was found to be the most prevalent in healthy controls (30.71 ± 8.44) while (20.57 ± 9.51) in CL-infected individuals. The class Alphaproteobacteria was found to be more in CL-infected individuals (5.47 ± 2.07) as compared to healthy controls (1.85 ± 0.39). The CL-infected individuals had a significantly lower relative abundance of the Clostridia class (p < 0.0001). An altered serum microbiome of CL infection and higher microbial abundance in the serum of healthy individuals was observed.


Assuntos
Leishmaniose Cutânea , Microbiota , Humanos , Microbiota/genética , Bactérias/genética , Metagenoma , Proteobactérias/genética , Inflamação/genética , RNA Ribossômico 16S/genética
4.
Acta Trop ; 235: 106659, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35988821

RESUMO

The pathophysiology of Cutaneous Leishmaniasis (CL), an infection caused by Leishmania tropica (L. tropica) and Leishmania major (L. major) is primarily determined by inflammation-mediated immune cells. The immune response mainly depends on cells and molecules related to T-cells that influence susceptibility and disease development. Understanding the immunological mechanisms that cause tissue injury or lesion healing is critical for developing appropriate treatment strategies. In the present study, T-cells profile and cell-free mitochondrial DNA (CF mt-DNA) were investigated in CL patients infected with L. tropica (n = 34) and L. major (n = 2) and compared with non-infected healthy controls (n = 20). There was a significant (p<0.0001) difference between CD4+ T-cells among L. tropica and L. major CL-infected groups as compared to control while no significant difference (p = 0.8597) was found in the percentages of CD8+ T-cells. When L. tropica and L. major CL-infected individuals were compared to controls, the levels of IL-4 and expression of CF mt-DNA were significantly higher (p<0.0001). Higher levels of CF mt-DNA were detected in CL patients, irrespective of the infective Leishmania species. We proposed that the levels of CF mt-DNA and IL-4 in CL-infected individuals can be used to determine the disease progression. A better understanding of these biomarkers and evaluation of the immune responses in CL patients might benefit the development of vaccines and immunotherapies.


Assuntos
Leishmania tropica , Leishmaniose Cutânea , DNA , Humanos , Interleucina-4 , Leishmania tropica/genética , Índice de Gravidade de Doença
5.
BMC Vet Res ; 17(1): 388, 2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922529

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) are undifferentiated cells that can give rise to a mesoderm lineage. Adipose-derived MSCs are an easy and accessible source for MSCs isolation, although each source of MSC has its own advantages and disadvantages. Our study identifies a promising source for the isolation and differentiation of canines MSCs. For this purpose, adipose tissue from inguinal subcutaneous (SC), perirenal (PR), omental (OM), and infrapatellar fat pad (IPFP) was isolated and processed for MSCs isolation. In the third passage, MSCs proliferation/metabolism, surface markers expression, in vitro differentiation potential and quantitative reverse transcription PCR (CD73, CD90, CD105, PPARγ, FabP4, FAS, SP7, Osteopontin, and Osteocalcin) were evaluated. RESULTS: Our results showed that MSCs derived from IPFP have a higher proliferation rate, while OM-derived MSCs have higher cell metabolism. In addition, MSCs from all adipose tissue sources showed positive expression of CD73 (NT5E), CD90 (THY1), CD105 (ENDOGLIN), and very low expression of CD45. The isolated canine MSCs were successfully differentiated into adipogenic and osteogenic lineages. The oil-red-O quantification and adipogenic gene expression (FAS, FabP4, and PPARγ) were higher in OM-derived cells, followed by IPFP-MSCs. Similarly, in osteogenic differentiation, alkaline phosphatase activity and osteogenic gene (SP7 and Osteocalcin) expression were higher in OM-derived MSCs, while osteopontin expression was higher in PR-derived MSCs. CONCLUSION: In summary, among all four adipose tissue sources, OM-derived MSCs have better differentiation potential toward adipo- and osteogenic lineages, followed by IPFP-MSCs. Interestingly, among all adipose tissue sources, MSCs derived from IPFP have the maximum proliferation potential. The characterization and differentiation potential of canine MSCs isolated from four different adipose tissue sources are useful to assess their potential for application in regenerative medicine.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Células-Tronco Mesenquimais , Osteogênese , Animais , Proliferação de Células , Células Cultivadas , Cães , Células-Tronco Mesenquimais/citologia , Osteocalcina , Osteopontina , PPAR gama
6.
Infect Genet Evol ; 96: 105120, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34655808

RESUMO

Plasmodium vivax-induced malaria is among the leading causes of morbidity and mortality in sub-tropical and tropical regions and infect 2.85 billion people globally. The continual rise and propagation of resistance against anti-malarial drugs is a prerequisite to develop a potent vaccine candidate for Plasmodium vivax (P. vivax). Circumsporozoite protein (CSP) is an important immunogen of malaria parasite that has the conserved CSP structure as an immune dominant B-cell epitope. In current study, we focused on designing multi-epitope vaccines (MEVs) using various immunoinformatics tools against Pakistani based allelic variants VK210 and VK247 of P. vivax CSP (PvCSP) gene. Antigenicity, allergic potential and physicochemical parameters of both PvCSP variants were assessed for the designed MEVs and they were within acceptable range suitable for post experimental investigations. The three-dimensional structures of both MEVs have been predicted ab initio, optimized, and validated by using different online servers. The both MEVs candidates were stable and free from aggregation-prone regions. The stability of both MEVs had been improved by a disulfide engineering approach. To estimate the binding energy and stability of the MEVs, molecular docking simulation and binding free energy calculations with TLR-4 immune receptor have been conducted. The docking score of PvCSP210 and PvCSP247 for TLR-4 was -6.34 kJ/mol and - 2.3 kJ/mol, respectively. For PvCSP210-TLR4 system, mean RMSD was 4.96 Å while PvCSP247-TLR4 system, average RMSD was 4.49 Å. The binding free energy of PvCSP210-TLR4 complex and PvCSP247-TLR4 complex was -50.49/-117.15 kcal/mol (MMGBSA/MMPSA) and -52.94/-96.26 kcal/mol (MMGBSA/MMPSA), respectively. The expression of both MEVs produced in Escherichia coli K12 expression system by in silico cloning was significant. Immune simulation revealed that the proposed MEVs induce strong humoral and cellular immunological responses, in addition to significant production of interleukins and cytokines. In conclusions, we believed that the MEVs proposed in current research, using combine approach of immunoinformatics, structural biology and biophysical approaches, could induce protective and effective immune responses against P. vivax and the experimental validation of our findings could contribute to the development of potential malaria vaccine.


Assuntos
Epitopos Imunodominantes/imunologia , Plasmodium vivax/fisiologia , Proteínas de Protozoários/genética , Epitopos Imunodominantes/genética , Proteínas de Protozoários/imunologia
7.
Genomics ; 113(6): 4015-4021, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34637930

RESUMO

HIV infects the CD4 cells which marks the suppression of our immune system. DNA from serum of healthy, treated and untreated HIV infected individuals was extracted. The DNA was subjected to 16S metagenomic sequencing and analyzed using QIIME2 pipeline. 16S sequencing analysis showed serum microbiome was dominated by Firmicutes, Proteobacteria, Bacteroidota and Actinobacteria. Treated HIV infection showed highest abundance of Firmicutes (66.40%) significantly higher than untreated HIV infection (35.88%) and control (41.89%). Bacilli was most abundant class in treated (63.59%) and second most abundant in untreated (34.53%) while control group showed highest abundance of class Gamma-proteobacteria (45.86%). Untreated HIV infection group showed Enterococcus (10.72%) and Streptococcus (6.599%) as the most abundant species. Untreated HIV infection showed significantly higher (p = 0.0039) species richness than treated and control groups. An altered serum microbiome of treated HIV infection and higher microbial abundance in serum of untreated HIV infection was observed.


Assuntos
Infecções por HIV , Microbiota , Infecções por HIV/genética , Humanos , Metagenoma , Metagenômica , RNA Ribossômico 16S/genética
9.
Mol Biol Rep ; 48(4): 3327-3336, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33886057

RESUMO

HIV infection is a global health concern. Current HIV-diagnostics provide information about the disease progression and efficacy of anti-retroviral therapies (ARVs), but this information is very limited and sometimes imprecise. Present study assessed the potential role of mononuclear cell (MNC) death, expression of caspases (1&3) and cell free mitochondrial DNA (CF mt-DNA) in HIV infected individuals. Apoptosis, cell-count, expression of caspases and CF mt-DNA were measured through flow cytometry and qPCR, respectively, in HIV infected individuals (n = 120) divided in two groups i.e. ARVs-receiving (treated, n = 87), ART-naïve (untreated, n = 37) and healthy individuals (n = 47). Data showed significant (p < 0.0001) cell death in untreated individuals than treated and healthy individuals. CD4-positive T-cell percentage declined (p < 0.0001) in untreated as compared to treated individuals. Caspase-1, an indicator of pyroptosis, and CF mt-DNA were also elevated in untreated HIV infected individuals. Untreated individuals when administered with ARVs showed improved CD4-positive T-cell percentage, lower caspase-1, CF mt-DNA and cell death. Data elucidated positive co-relation between cell death and CF mt-DNA in treated and untreated HIV infected individuals. While CD4-positive T-cell percentage was negatively correlated with caspase-1 expression and CF mt-DNA. Elevated levels of CF mt-DNA and caspase-1 in HIV infected individuals, positive correlation between cell death and CF mt-DNA, negative correlation of CD4-positive T-cell percentage with CF mt-DNA and caspase-1 expression clearly indicated the potential of CF mt-DNA and caspase-1 as a novel disease progression and ARTs effectiveness biomarkers in HIV.


Assuntos
Antivirais/uso terapêutico , Caspase 1/genética , DNA Mitocondrial/sangue , Infecções por HIV/sangue , Adulto , Apoptose , Ácidos Nucleicos Livres/sangue , Feminino , Regulação da Expressão Gênica , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
10.
Malar J ; 20(1): 112, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632220

RESUMO

BACKGROUND: Plasmodium vivax contributes to over 70% malaria burden in Pakistan, but limited data exists on various aspects including genetic diversity of the parasite as compared to other parts of the world. Since the information about the genetic diversity of P. vivax assists to understand the population dynamics of the parasite, the current study was designed to understand population divergence of P. vivax in Pakistan using circumsporozoite protein (pvcsp) and merozoite surface protein-1 (pvmsp-1) genes as molecular markers. METHODS: The PCR for pvcsp and pvmsp-1 genes was carried out for 150 P. vivax isolates, followed by DNA sequencing of 35 and 30, respectively. Genetic diversity and polymorphism were analysed using ChromasPro, ClustalW, MEGA7, DnaSP v.5 and WebLogo programs. RESULTS: The PCR for pvcsp and pvmsp-1 genes was carried out for 150 P. vivax isolates and resulting the PCR products of 1100 bp for pvcsp and ~ 400 bp for pvmsp-1 genes, respectively. In the central-repeat region (CRR) of pvcsp gene, sequences comprised of four variable repeats of PRMs, out of which GDRADGQPA (PRM1), GDRAAGQPA (PRM2) were more extensively dispersed among the P. vivax isolates. Partial sequences (~ 400 bp) of block 2 of pvmsp-1 gene depicted high level of diversity. CONCLUSION: The results revealed the polymorphism and genetic diversity especially at the CRR of pvcsp and block 2 of pvmsp-1 genes, respectively. The base-line data presented here warrants future studies to investigate more into the genetic diversity of P. vivax with large sample size from across the country for better understanding of population dynamics of P. vivax that will help to control malaria at individual and community level.


Assuntos
Proteína 1 de Superfície de Merozoito/genética , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Marcadores Genéticos , Malária Vivax , Paquistão
11.
Genomics ; 113(1 Pt 1): 183-192, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326831

RESUMO

Chloroplast (cp) genomes are considered important for the study of lineage-specific molecular evolution, population genetics, and phylogenetics. Our aim here was to elucidate the molecular evolution in cp genomes of species in the Dracunculus clade (Aroideae, Araceae). We report de novo assembled cp genomes for eight species from eight genera and also retrieved cp genomes of four species from the National Center for Biotechnology Information (NCBI). The cp genomes varied in size from 162,424 bp to 176,835 bp. Large Single Copy (LSC) region ranged in size from 87,141 bp to 95,475 bp; Small Single Copy (SSC) from 14,338 bp to 23,981 bp; and Inverted Repeats (IRa and IRb) from 25,131 bp to 32,708 bp. The expansion in inverted repeats led to duplication of ycf1 genes in four species. The genera showed high similarity in gene content and yielded 113 unique genes (79 protein-coding, 4 rRNA, and 30 tRNA genes). Codon usage, amino acid frequency, RNA editing sites, microsatellites repeats, transition and transversion substitutions, and synonymous and non-synonymous substitutions were also similar across the clade. A previous study reported deletion of ycf1, accD, psbE, trnL-CAA, and trnG-GCC genes in four Amorphophallus species. Our study supports conservative structure of cp genomes in the Dracunculus clade including Amorphophallus species and does not support gene deletion mentioned above. We also report suitable polymorphic loci based on comparative analyses of Dracunculus clade species, which could be useful for phylogenetic inference. Overall, the current study broad our knowledge about the molecular evolution of chloroplast genome in aroids.


Assuntos
Araceae/genética , Evolução Molecular , Genoma de Cloroplastos/genética , Araceae/classificação , Uso do Códon , Dosagem de Genes , Repetições de Microssatélites , Anotação de Sequência Molecular , Filogenia
12.
Parasitology ; 148(5): 591-597, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33353570

RESUMO

Cutaneous Leishmaniasis (CL) is considered a neglected tropical disease which in Pakistan can now be considered as a growing public health problem. The exact figures on the magnitude of the disease are lacking both at the national and regional level and only a few health centres are available for diagnosis of CL. The present study was designed to identify the epidemiology of CL infection from August 2018 to December 2019 and to assess clinical aspects of CL in Baluchistan Province of Pakistan. A total of 4072 clinically suspected CL cases were analysed statistically. The highest number of CL cases were reported in May, followed by April, January and then July, February and June and the lowest number of cases were observed in March and November. The highest prevalence rate was found in males where 38% of reported cases were aged 0-9 years. The majority (24.4%) of lesions were found on the hands followed by the face in which cheeks, ears and nose were the effected organs. About 50% of the participants have single lesion while 14% of the participants had two and nearly 3% of the participants have six lesions. The atypical clinical presentations were observed in Baluchistan and common unusual presentations were lupus erythematosus. The study findings suggest that more epidemiological studies and health education campaigns are needed for the population awareness regarding CL in Baluchistan. It is recommended that risk factors should be evaluated to establish control and management strategies to prevent disease at the individual and community level.


Assuntos
Leishmaniose Cutânea/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Leishmania tropica/fisiologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Adulto Jovem
13.
Pak J Med Sci ; 36(5): 860-866, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32704253

RESUMO

OBJECTIVE: Cell Free mitochondrial DNA (CF mt-DNA) has emerged as a novel biomarker to investigate disease pathophysiology of different infections. The present study was designed to elucidate the association between CF mt-DNA, IL-6 and viral load in HIV, HBV and HCV infections and predict its role as a potential biomarker to assess the disease severity in viral infections. METHODS: Total 120 blood samples were collected from January 2018 to December 2018 of HIV, HBV and HCV patients and healthy controls (30 samples in each group). DNA and RNA were extracted from the serum to determine the levels of CF mt-DNA and viral load, respectively. IL-6 from the serum of infected individuals was quantified with ELISA. RESULTS: HCV patients showed the highest levels of CF mt-DNA, IL-6 and viral load, followed by HBV and HIV. Significant correlation was found between CF mt-DNA and IL-6 among the HBV patients (p=0.017). However, no significant correlation of CF mt-DNA was observed with IL-6 in HIV and HCV or with the viral load in any of the three infections. CONCLUSION: Elevated CF mt-DNA indicates its role in severity of viral infections. Independence of CF mt-DNA expression from viral load and IL-6 in case of HIV and HCV suggests involvement of other inflammatory pathways regulating CF mt-DNA elevation.

14.
Genomics ; 112(1): 581-591, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30998967

RESUMO

Previous studies to resolve phylogenetic and taxonomic discrepancies of Hibiscus remained inconclusive. Here, we report chloroplast genome sequence of Hibiscus rosa-sinensis. Hibiscus rosa-sinensis chloroplast genome was 160,951 bp, comprising of large single copy (89,509 bp) and small single copy (20,246 bp) regions, separated by IRa and IRb (25,598 bp each). The genome contained 130 genes including 85 protein-coding genes, 37 transfer RNAs and 8 ribosomal RNAs. Comparative analyses of chloroplast genomes revealed similar structure among 12 species within family Malvaceae. Evolutionary rates of 77 protein-coding genes showed 95% similarities. Analyses of codon usage, amino acid frequency, putative RNA editing sites, and repeats showed a great extent of similarities between Hibiscus rosa-sinensis and Hibiscus syriacus. We identified 30 mutational hotpots including psbZ-trnG, trnK-rps16, trnD-trnY, trnW-trnP, rpl33-rps18, petG-trnW, trnS-trnG, trnH-psbA, atpB-rbcL, and rpl32-trnL that might be used as polymorphic and robust markers to resolve phylogenetic discrepancies in genus Hibiscus.


Assuntos
Proteínas de Cloroplastos/genética , Evolução Molecular , Genoma de Cloroplastos , Hibiscus/genética , Mutação , RNA de Cloroplastos/genética
15.
Iran J Immunol ; 13(1): 1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27026041

RESUMO

BACKGROUND: Falciparum malaria is a severe health burden worldwide. Antigen presenting cells are reported to be affected by erythrocytic stage of the parasite. Malarial hemozoin (HZ), a metabolite of malaria parasite, has adjuvant properties and may play a role in the induction of immune response against the parasite. OBJECTIVE: To determine the immunological impact of hemozoin on the capacity of innate immune cells maturation. METHODS: Plasmodium falciparum (F32 strain) was cultured in O+ blood group up to 18% parasitemia. Natural hemozoin was extracted from infected red blood cells. Murine bone marrow derived macrophages and myeloid dendritic cells were stimulated with 4 µg/mL or 40 µg/mL of synthetic hemozoin (ß-hematin) or natural hemozoin. We assessed the immunomodulatory role of synthetic or natural hemozoinin vitro by flowcytometric analysis. RESULTS: The maturation markers MHC-II, CD80 and CD86 were significantly upregulated (p<0.05) on the surface of murine bone marrow derived macrophages or myeloid dendritic cells. Data confirmed the potential of macrophages or myeloid dendritic cells, through hemozoin activation, to establish an innate immune response against malaria parasites. CONCLUSION: Both synthetic and natural hemozoin are potent inducers of cellular immunity against malaria infection. However, natural hemozoin is a stronger inducer as compared to synthetic hemozoin.


Assuntos
Diferenciação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Hemeproteínas/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Células Mieloides/citologia , Células Mieloides/imunologia , Animais , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Biomarcadores , Células Dendríticas/metabolismo , Feminino , Imunidade Inata , Imunofenotipagem , Macrófagos/metabolismo , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Camundongos , Células Mieloides/metabolismo , Parasitemia/imunologia , Parasitemia/parasitologia , Plasmodium falciparum/imunologia
16.
Int J Mol Sci ; 15(5): 8821-34, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24852940

RESUMO

Specific labelling of target cell surfaces using antibody-conjugated paramagnetic nanobeads is essential for efficient magnetic cell separation. However, studies examining parameters determining the kinetics of bead-cell binding are scarce. The present study determines the binding rates for specific and unspecific binding of 150 nm paramagnetic nanobeads to highly purified target and non-target cells. Beads bound to cells were enumerated spectrophotometrically. Results show that the initial bead-cell binding rate and saturation levels depend on initial bead concentration and fit curves of the form A(1 - exp(-kt)). Unspecific binding within conventional experimental time-spans (up to 60 min) was not detectable photometrically. For CD3-positive cells, the probability of specific binding was found to be around 80 times larger than that of unspecific binding.


Assuntos
Anticorpos/química , Nanopartículas de Magnetita/química , Anticorpos/imunologia , Complexo CD3/imunologia , Complexo CD3/metabolismo , Citometria de Fluxo , Humanos , Cinética , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Receptores de Lipopolissacarídeos/imunologia , Receptores de Lipopolissacarídeos/metabolismo , Tamanho da Partícula , Espectrofotometria
17.
Vaccine ; 30(37): 5578-84, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21983157

RESUMO

A protective malaria vaccine may induce both high levels of neutralising antibodies and strong T-cell responses. The Plasmodium falciparum circumsporozoite protein (CSp) is a leading pre-erythrocytic vaccine candidate. CSp is a week immunogen per se, but Mycobacterium bovis Bacille Calmette-Guérin (BCG) has excellent adjuvant activity and has been utilized as a vector to deliver heterologous vaccine candidate antigens. It is safe in immunocompetent individuals and inexpensive to produce. We assessed in vitro and in vivo a recombinant BCG-expressing CSp (BCG-CS) as malaria vaccine candidate. Immunisation of BALB/c mice with BCG-CS augmented numbers of dendritic cells (DCs) in draining lymph nodes and in the spleen. The activation markers MHC-class-II, CD40, CD80 and CD86 on DCs were significantly upregulated by BCG-CS as compared to wild-type BCG (wt-BCG). In vitro stimulation of bone marrow-derived DCs and macrophages with BCG-CS induced IL-12 and TNF-α production. BCG-CS induced higher phagocytic activity in macrophages as compared to wt-BCG. Immunogenicity studies show that BCG-CS induced CS-specific antibodies and IFN-γ-producing memory cells. In conclusion, BCG-CS is highly efficient in activating antigen-presenting cells (APCs) for priming of adaptive immunity. Implications for the rational design of novel vaccines against malaria and TB, the two major devastating poverty-related diseases, are discussed.


Assuntos
Células Dendríticas/imunologia , Memória Imunológica , Vacinas Antimaláricas/imunologia , Mycobacterium bovis/genética , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Vacinas Sintéticas/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Antígeno B7-1/imunologia , Antígeno B7-2/imunologia , Biomarcadores/metabolismo , Antígenos CD40/imunologia , Feminino , Interferon gama/imunologia , Interleucina-12/imunologia , Interleucina-12/metabolismo , Vacinas Antimaláricas/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose/imunologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Baço/imunologia , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Vacinas Sintéticas/genética
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