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1.
Am J Pathol ; 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33539779

RESUMO

IFN-γ is indispensable for the resolution of cutaneous leishmaniasis (CL) while Th2 cytokines IL-4, IL-10, and IL-13 mediate susceptibility. A recent study found that MicroRNA 155 (miR155), which promotes CD4+ Th1 response and IFN-γ production, is dispensable for control of Leishmania donovani infection. Here, the role of miR155 in CL caused by L. major was investigated using miR155 deficient (miR155-/-) mice. miR155-/- mice controlled infection significantly quicker than their WT counterparts indicating that miR155 contributes to the pathogenesis of CL. Faster resolution of infection in miR155-/- mice was associated with increased levels of Th1 associated IL-12 and IFN-γ and reduced production of Th2 associated IL-4, IL-10, and IL-13. Flow cytometric analysis showed that L. major infected miR155-/- mice contained significantly higher proportions of IFN-γ+CD8 T cells and NK cells in draining lymph nodes than infected WT mice. Following in vitro IFN-γ stimulation, L. major-infected miR155-/- DCs displayed increased nitric oxide and IL-12 production, decreased IL-10 production, and enhanced parasite clearance compared to WT DCs. Furthermore, L. major-infected miR155-/- DCs significantly enhanced IFN-γ production from activated miR155-/- T cells. Together these findings demonstrate that miR155 promotes susceptibility to CL caused by L. major by promoting Th2 response and inhibiting DC function.

2.
Biochem Soc Trans ; 49(1): 297-311, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33449103

RESUMO

Leishmaniasis is a vector-borne Neglected Tropical Disease (NTD) transmitted by the sand fly and is a major public health problem worldwide. Infections caused by Leishmania clinically manifest as a wide range of diseases, such as cutaneous (CL), diffuse cutaneous (DCL), mucosal (MCL) and visceral leishmaniasis (VL). The host innate and adaptative immune responses play critical roles in the defense against leishmaniasis. However, Leishmania parasites also manipulate the host immune response for their survival and replication. In addition, other factors such as sand fly salivary proteins and microbiota also promote disease susceptibility and parasite spread by modulating local immune response. Thus, a complex interplay between parasite, sand fly and the host immunity governs disease severity and outcome. In this review, we discuss the host immune response during Leishmania infection and highlight the factors associated with resistance or susceptibility.

3.
Vessel Plus ; 42020.
Artigo em Inglês | MEDLINE | ID: mdl-33089078

RESUMO

The vascular endothelium is a vital component in maintaining the structure and function of blood vessels. The endothelial cells (ECs) mediate vital regulatory functions such as the proliferation of cells, permeability of various tissue membranes, and exchange of gases, thrombolysis, blood flow, and homeostasis. The vascular endothelium also regulates inflammation and immune cell trafficking, and ECs serve as a replicative niche for many bacterial, viral, and protozoan infectious diseases. Endothelial dysfunction can lead to vasodilation and pro-inflammation, which are the hallmarks of many severe diseases. Exosomes are nanoscale membrane-bound vesicles that emerge from cells and serve as important extracellular components, which facilitate communication between cells and maintain homeostasis during normal and pathophysiological states. Exosomes are also involved in gene transfer, inflammation and antigen presentation, and mediation of the immune response during pathogenic states. Protozoa are a diverse group of unicellular organisms that cause many infectious diseases in humans. In this regard, it is becoming increasingly evident that many protozoan parasites (such as Plasmodium, Trypanosoma, Leishmania, and Toxoplasma) utilize exosomes for the transfer of their virulence factors and effector molecules into the host cells, which manipulate the host gene expression, immune responses, and other biological activities to establish and modulate infection. In this review, we discuss the role of the vascular endothelium and exosomes in and their contribution to pathogenesis in malaria, African sleeping sickness, Chagas disease, and leishmaniasis and toxoplasmosis with an emphasis on their actions on the innate and adaptive immune mechanisms of resistance.

4.
Parasit Vectors ; 13(1): 510, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046138

RESUMO

BACKGROUND: Leishmaniasis is a neglected tropical disease affecting millions of people worldwide. Emerging drug resistance of Leishmania species poses threaten to the effective control and elimination programme of this neglected tropical disease. METHODS: In this work, we conducted drug-resistance testing, whole genome resequencing and proteome profiling for a recently reported clinical isolate with supposed drug resistance (HCZ), and two reference sensitive strains (DD8 and 9044) of Leishmania donovani, to explore molecular mechanisms underlying drug resistance in this parasite. RESULTS: With reference to DD8 and 9044 strains, HCZ isolate showed higher-level virulence and clear resistance to antimonials in promastigote culture, infected macrophages and animal experiment. Pairwise genomic comparisons revealed genetic variations (86 copy number variations, 271 frameshift mutations in protein-coding genes and two site mutations in non-coding genes) in HCZ isolate that were absent from the reference sensitive strains. Proteomic analysis indicated different protein expression between HCZ isolate and reference strains, including 69 exclusively detected proteins and 82 consistently down-/upregulated molecules in the HCZ isolate. Integrative analysis showed linkage of 12 genomic variations (gene duplication, insertion and deletion) and their protein expression changes in HCZ isolate, which might be associated with pathogenic and antimony-resistant phenotype. Functional annotation analyses further indicated that molecules involved in nucleotide-binding, fatty acid metabolism, oxidation-reduction and transport might play a role in host-parasite interaction and drug-resistance. CONCLUSIONS: This comprehensive integrative work provided novel insights into the genetic basis underlying virulence and resistance, suggesting new aspects to be investigated for a better intervention against L. donovani and associated diseases.

5.
Cell Death Dis ; 11(9): 774, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943608

RESUMO

Triple-negative breast cancer (TNBC), defined as loss of estrogen, progesterone, and Her2 receptors, is a subtype of highly aggressive breast cancer with worse prognosis and poor survival rate. Macrophage migration inhibitory factor (MIF) is a pleiotropic pro-inflammatory cytokine aberrantly expressed in many solid tumors and known to promote tumor progression and metastasis. However, its role in TNBC progression and metastasis is unexplored. Here we have shown that in TNBC patients, MIF expression was significantly enriched in the tumor compared to adjacent normal tissue. Using publically available patient datasets, we showed that MIF overexpression correlates with worse survival in TNBC compared to other hormonal status. Orthotopic implantation of TNBC cells into MIF knockout mice showed reduced tumor growth compared to wild-type mice. In addition, we have shown that MIF downregulation inhibits TNBC growth and progression in a syngeneic mouse model. We further showed that CPSI-1306, a small-molecule MIF inhibitor, inhibits the growth of TNBC cells in vitro. Mechanistic studies revealed that CPSI-1306 induces intrinsic apoptosis by alteration in mitochondrial membrane potential, cytochrome c (Cyt c) release, and activation of different caspases. In addition, CPSI-1306 inhibits the activation of cell survival and proliferation-related molecules. CPSI-1306 treatment also reduced the tumor growth and metastasis in orthotopic mouse models of mammary carcinoma. CPSI-1306 treatment of tumor-bearing mice significantly inhibited TNBC growth and pulmonary metastasis in a dose-dependent manner. Histological analysis of xenograft tumors revealed a higher number of apoptotic cells in CPSI-1306-treated tumors compared to vehicle controls. Our studies, for the first time, show that MIF overexpression in TNBC enhances growth and metastasis. Taken together, our results indicate that using small molecular weight MIF inhibitors could be a promising strategy to inhibit TNBC progression and metastasis.

6.
Nat Commun ; 11(1): 3461, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651371

RESUMO

Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa transmitted by infected sand flies. Vaccination through leishmanization with live Leishmania major has been used successfully but is no longer practiced because it resulted in occasional skin lesions. A second generation leishmanization is described here using a CRISPR genome edited L. major strain (LmCen-/-). Notably, LmCen-/- is a genetically engineered centrin gene knock-out mutant strain that is antibiotic resistant marker free and does not have detectable off-target mutations. Mice immunized with LmCen-/- have no visible lesions following challenge with L. major-infected sand flies, while non-immunized animals develop large and progressive lesions with a 2-log fold higher parasite burden. LmCen-/- immunization results in protection and an immune response comparable to leishmanization. LmCen-/- is safe since it is unable to cause disease in immunocompromised mice, induces robust host protection against vector sand fly challenge and because it is marker free, can be advanced to human vaccine trials.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Leishmania major/genética , Leishmania major/patogenicidade , Vacinas Atenuadas/uso terapêutico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Dexametasona/farmacologia , Feminino , Citometria de Fluxo , Edição de Genes , Engenharia Genética , Humanos , Imunossupressão , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Psychodidae/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Vaccine ; 38(36): 5803-5813, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32684498

RESUMO

Listeria monocytogenes is a facultative intracellular pathogen responsible for the life-threatening disease listeriosis. The pore-forming toxin listeriolysin O (LLO) is a critical virulence factor that plays a major role in the L. monocytogenes intracellular lifecycle and is indispensable for pathogenesis. LLO is also a dominant antigen for T cells involved in sterilizing immunity and it was proposed that LLO acts as a T cell adjuvant. In this work, we generated a novel full-length LLO toxoid (LLOT) in which the cholesterol-recognition motif, a threonine-leucine pair located at the tip of the LLO C-terminal domain, was substituted with two glycine residues. We showed that LLOT lost its ability to bind cholesterol and to form pores. Importantly, LLOT retained binding to the surface of epithelial cells and macrophages, suggesting that it could efficiently be captured by antigen-presenting cells. We then determined if LLOT can be used as an antigen and adjuvant to protect mice from L. monocytogenes infection. Mice were immunized with LLOT alone or together with cholera toxin or Alum as adjuvants. We found that mice immunized with LLOT alone or in combination with the Th2-inducing adjuvant Alum were not protected against L. monocytogenes. On the other hand, mice immunized with LLOT along with the experimental adjuvant cholera toxin, were protected against L. monocytogenes, as evidenced by a significant decrease in bacterial burden in the liver and spleen three days post-infection. This immunization regimen elicited mixed Th1, Th2, and Th17 responses, as well as the generation of LLO-neutralizing antibodies. Further, we identified T cells as being required for immunization-induced reductions in bacterial burden, whereas B cells were dispensable in our model of non-pregnant young mice. Overall, this work establishes that LLOT is a promising vaccine antigen for the induction of protective immunity against L. monocytogenes by subunit vaccines containing Th1-driving adjuvants.

8.
Eur J Pharm Biopharm ; 152: 307-317, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32485227

RESUMO

The present study aimed on the site specific delivery and enhanced in-vivo efficacy of antimonial drugs against the visceral leishmaniasis via macrophage targeted mannose anchored thiomer based nanoparticles. Mannose anchored thiolated nanoformulation [M-(CS-g-PEI)-TGA] was developed and evaluated in terms particle size, zeta-potential and entrapment efficacy. The TEM and EDX analysis was carried out to evaluate the morphology and successful entrapment of antimonial drug. Mucodhesion, permeation enhancement, oral pharmacokinetics, and in-vivo anti-leishmanial activity were carried out. The M-(CS-g-PEI)-TGA were found to be spherical having particle size of 287 ± 20 nm. Ex-vivo permeation indicated a 7.39-fold enhanced permeation of Meglumine Antimoniate with M-(CS-g-PEI)-TGA across Caco-2 cells compared to the Glucantime. Evaluation of in-vitro reduction in the parasitic burden via flow cytometric analysis indicated a 5.7-fold lower IC50 for M-(CS-g-PEI)-TGA compared to Glucantime. A 6.1-fold improvement in the oral bioavailability and 5.2-fold reduced parasitic burden in the L. donovani infected BALB/c mice model was observed with M-(CS-g-PEI)-TGA compared to Glucantime. The results encouraged the concept of M-(CS-g-PEI)-TGA nanoformulations as a promising strategy for oral therapy against visceral leishmaniasis.

9.
Acta Parasitol ; 65(4): 936-948, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32557082

RESUMO

Sanliurfa, a city in southeastern Turkey, is host to 477,166 Syrian refugees. The incidence of cutaneous leishmaniasis (CL) may be on the rise in areas affected by a refugee crisis, like Sanliurfa; thus, consequently, local uncommon species of Leishmania may be encountered in these regions. This might potentially make diagnosis and treatment more challenging over time. In this study, it was aimed to identify the causative agents of CL in clinical samples. A total of 154 patients (60 Syrian and 94 Turkish) who were diagnosed with CL via microscopical examination and PCR were enrolled this study. All of the samples were analyzed using internal transcribed spacer 1 genes, restriction fragment length polymorphism, DNA-sequencing, and phylogenetic analyses. In this study, Leishmania tropica was determined to be the predominant species in 140 of the patients (90.9%), followed by Leishmania major in 12 patients (7.8%), and Leishmania infantum in 2 patients (1.3%). Of the 94 Turkish patients, 94.7% were infected with L. tropica and 5.3% were infected with L. major, while none were infected with L. infantum. However, of the 60 Syrian patients, 85% were infected with L. tropica, 11.7% were infected with L. major, and 3.3% were infected with L. infantum. There was a significant association between the Leishmania species and the nations (Turkish-Syrian) (P < 0.001). The sequences were numbered from MH347941 to MH347953 and submitted to GenBank. This study confirmed that L. tropica, L. major, and L. infantum coexisted in Sanliurfa. This was the first time that the species L. infantum was reported among recent immigrants from Syria in Sanliurfa. Therefore, it is necessary to discriminate the Leishmania species for diagnosis, treatment, and controlled studies in hyper-endemic regions.

10.
Infect Immun ; 88(7)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32312766

RESUMO

Chagas disease, caused by the intracellular protozoan parasite Trypanosoma cruzi, is a public health problem affecting 6 to 8 million people, mainly in Latin America. The role of microRNAs in the pathogenesis of Chagas disease has not been well described. Here, we investigate the role of microRNA-155 (miR-155), a proinflammatory host innate immune regulator responsible for T helper type 1 and type 17 (Th1 and Th17) development and macrophage responses during T. cruzi infection. For this, we compared the survival and parasite growth and distribution in miR-155-/- and wild-type (WT) C57BL/6 mice. The lack of miR-155 caused robust parasite infection and diminished survival of infected mice, while WT mice were resistant to infection. Immunological analysis of infected mice indicated that, in the absence of miR-155, there was decreased interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) production. In addition, we found that there was a significant reduction of CD8-positive (CD8+) T cells, natural killer (NK) cells, and NK-T cells and increased accumulation of neutrophils and inflammatory monocytes in miR-155-/- mice. Collectively, these data indicate that miR-155 is an important immune regulatory molecule critical for the control of T. cruzi infection.

11.
Eur J Pharm Sci ; 145: 105256, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32032778

RESUMO

The present study evaluates the efficacy of sodium stibogluconate (SSG) co-loaded with ketoconazole (KTZ) in nano-elastic liposomes (NELs) for the topical treatment of cutaneous leishmaniasis (CL). SSG-KTZ co-loaded NELs were developed and assessed for various physicochemical properties and anti-leishmanial potential. The optimized nano-vesicles have an average size of 212.8 ± 3.1 nm and entrapment efficiency of 61.2 ± 2.9%. SSG-KTZ co-loaded NELs displayed 5.37-fold higher skin permeation of SSG as compared to drug solution. SSG and KTZ displayed a synergistic interaction and flow cytometry revealed enhanced killing of DsRed Leishmania mexicana in infected macrophages. In-vitro and in-vivo anti-leishmanial studies indicated a 10.67-fold lower IC50 value and a 35.33-fold reduced parasitic burden as compared with plain SSG solution, respectively. SSG-KTZ co-loaded NELs were found to be a promising approach for the topical treatment of CL.


Assuntos
Gluconato de Antimônio e Sódio/administração & dosagem , Antiprotozoários/administração & dosagem , Elasticidade , Cetoconazol/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Nanopartículas/administração & dosagem , Administração Tópica , Animais , Gluconato de Antimônio e Sódio/metabolismo , Antiprotozoários/metabolismo , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/metabolismo , Feminino , Cetoconazol/metabolismo , Leishmaniose Cutânea/metabolismo , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/metabolismo , Técnicas de Cultura de Órgãos , Distribuição Aleatória , Pele/efeitos dos fármacos , Pele/metabolismo
12.
Br J Cancer ; 122(7): 1005-1013, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32025027

RESUMO

BACKGROUND: Ibrutinib is a Bruton's tyrosine kinase (BTK) and interleukin-2-inducible kinase (ITK) inhibitor used for treating chronic lymphocytic leukaemia (CLL) and other cancers. Although ibrutinib is known to inhibit the growth of breast cancer cell growth in vitro, its impact on the treatment and metastasis of breast cancer is unclear. METHODS: Using an orthotopic mouse breast cancer model, we show that ibrutinib inhibits the progression and metastasis of breast cancer. RESULTS: Ibrutinib inhibited proliferation of cancer cells in vitro, and Ibrutinib-treated mice displayed significantly lower tumour burdens and metastasis compared to controls. Furthermore, the spleens and tumours from Ibrutinib-treated mice contained more mature DCs and lower numbers of myeloid-derived suppressor cells (MDSCs), which promote disease progression and are linked to poor prognosis. We also confirmed that ex vivo treatment of MDSCs with ibrutinib switched their phenotype to mature DCs and significantly enhanced MHCII expression. Further, ibrutinib treatment promoted T cell proliferation and effector functions leading to the induction of antitumour TH1 and CTL immune responses. CONCLUSIONS: Ibrutinib inhibits tumour development and metastasis in breast cancer by promoting the development of mature DCs from MDSCs and hence could be a novel therapeutic agent for the treatment of breast cancer.

13.
Int J Cancer ; 146(6): 1717-1729, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31709529

RESUMO

Cancers of the oral cavity remain the sixth most diagnosed cancer worldwide, with high rates of recurrence and mortality. We determined the role of STAT1 during oral carcinogenesis using two orthotopic models in mice genetically deficient for Stat1. Metastatic (LY2) and nonmetastatic (B4B8) head and neck squamous cell carcinoma (HNSCC) cell lines were injected into the oral cavity of Stat1 deficient (Stat1-/- ) and Stat1 competent (Stat1+/+ ) mice. Stat1-/- mice displayed increased tumor growth and metastasis compared to Stat1+/+ mice. Mechanistically, Stat1-/- mice displayed impaired CD4+ and CD8+ T-cell expansion compared to Stat1+/+ mice. This was associated with enhanced T-cell exhaustion, and severely attenuated T-cell antitumor effector responses including reduced expression of IFN-γ and perforin at the tumor site. Interestingly, tumor necrosis factor (TNF)-α production by T cells in tumor-bearing mice was suppressed by Stat1 deficiency. This deficiency in T-cell expansion and functional responses in mice was linked to PD-1 and CD69 overexpression in T cells of Stat1-/- mice. In contrast, we observed increased accumulation of CD11b+ Ly6G+ myeloid derived suppressor cells in tumors, draining lymph nodes, spleens and bone marrow of tumor-bearing Stat1-/- mice, resulting in a protumorigenic microenvironment. Our data demonstrates that STAT1 is an essential mediator of the antitumor response through inhibition of myeloid derived suppressor cell accumulation and promotion of T-cell mediated immune responses in murine head and neck squamous cell carcinoma. Selective induction of STAT1 phosphorylation in HNSCC patients could potentially improve oral tumor outcomes and response to therapy.


Assuntos
Imunomodulação , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Fator de Transcrição STAT1/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Linfonodos/patologia , Masculino , Camundongos , Camundongos Knockout , Metástase Neoplásica , Estadiamento de Neoplasias , Fator de Transcrição STAT1/deficiência , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Microambiente Tumoral
14.
Int J Pharm ; 573: 118900, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31765786

RESUMO

The present study aims to optimize and evaluate amphotericin B (AmB) and miltefosine (MTF) co-loaded second generation ultra-deformable liposomes (SGUDLs) for the topical treatment of cutaneous leishmaniasis (CL). The development of an effective topical drug formulation against CL is desirable because of its non-invasive nature, which may potentially enhance the patient adherence and treatment accessibility. AmB-MTF co-loaded SGUDLs were prepared and characterized for size, entrapment efficiency (EE) and elasticity. The optimized formulation was then subjected to ex-vivo permeation studies in addition to cytotoxicity and anti-leishmanial assays. The co-loaded SGUDLs had an average size of 139.7 ± 1.7 nm and high EE of 77.8 ± 3.9% with respect to AmB. The ex-vivo permeation of co-loaded SGUDLs exhibited 6.15-fold higher permeation of AmB. A synergistic interaction was observed between AmB and MTF, and anti-leishmanial activity of co-loaded SGUDLs against amastigotes of Lesihmania mexicana indicated 8.62 and 6.12-fold lower IC50 values of AmB and MTF as compared to plain drug solutions, respectively. The results of the in-vivo study displayed a significant reduction in the parasitic burden in an infected BALB/c experimental model of CL. In conclusion, AmB-MTF co-loaded SGUDLs could be an effective topical treatment option against CL.


Assuntos
Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Fosforilcolina/análogos & derivados , Administração Cutânea , Anfotericina B/farmacocinética , Animais , Antiprotozoários/farmacocinética , Modelos Animais de Doenças , Combinação de Medicamentos , Composição de Medicamentos/métodos , Elasticidade , Feminino , Humanos , Concentração Inibidora 50 , Leishmania/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Lipossomos , Camundongos , Nanopartículas/química , Carga Parasitária , Tamanho da Partícula , Permeabilidade , Fosforilcolina/administração & dosagem , Fosforilcolina/farmacocinética , Pele/metabolismo , Pele/parasitologia
15.
Expert Opin Drug Deliv ; 17(1): 97-110, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31786952

RESUMO

Objective: To test the hypothesis that miltefosine (MTF)-polyphenol co-loaded second-generation nano-transfersomes (SGNTs) can be an effective approach for the topical treatment of cutaneous leishmaniasis (CL).Methods: The co-loaded SGNTs with various MTF-polyphenol combinations were developed, evaluated and compared for the entrapment efficiency, vesicle size, deformability index, ex-vivo permeation, cytotoxicity, and anti-leishmanial potential, using both in-vitro and in-vivo models.Results: The co-loaded SGNTs were spherical in shape, with an average size of 119 ± 1.5 nm and a high entrapment efficiency of 73.7 ± 3.7%. The ex-vivo study displayed a 3.2-fold higher permeation of MTF when entrapped in co-loaded SGNTs, whereas cytotoxicity potential of co-loaded SGNTs was 43.2% higher than the MTF solution. A synergistic interaction was observed between MTF and apigenin (APG) among all polyphenols and an 8.0-fold lower IC50 was found against amastigotes of DsRed Leishmania mexicana, compared with the plain MTF solution. Moreover, the in-vivo studies displayed a 9.5-fold reduced parasitic burden in the L. mexicana infected BALB/c mice treated with MTF-APG co-loaded SGNTs gel.Conclusions: The potential of MTF-APG co-loaded SGNTs topical formulation is established for the first time as an effective drug delivery strategy against CL.

16.
PLoS Negl Trop Dis ; 13(11): e0007865, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738761

RESUMO

Cutaneous leishmaniasis (CL) is the most common form of leishmaniasis and is caused by several species of Leishmania parasite. Clinical presentation of CL varies from a self-healing infection to a chronic form of the disease determined by the virulence of infecting Leishmania species and host immune responses to the parasite. Mouse models of CL show contradictory roles of lymphocytes in pathogenesis, while acquired immune responses are responsible for host protection from diseases. To reconcile the inconclusive roles of acquired immune responses in pathogenesis, we infected mice from various genetic backgrounds with two pathogenic strains of Leishmania major, Friedlin or 5ASKH, and assessed the outcome of the infections. Our findings showed that the genetic backgrounds of L. major determine the impact of lymphocytes for pathogenesis. In the absence of lymphocytes, L. major Friedlin induced the lowest inflammatory reaction and pathology at the site of infection, while 5ASKH infection induced a strong inflammatory reaction and severe pathology. Lymphocytes ameliorated 5ASKH mediated pathology, while it exacerbated pathology during Friedlin infection. Excess inflammatory reactions, like the recruitment of macrophages, neutrophils, eosinophils and production of pro-inflammatory cytokines, together with uncontrolled parasite growth in the absence of lymphocytes during 5ASKH infection may induce severe pathology development. Taken together our study provides insight into the impact of differences in the genetic background of Leishmania on CL pathogenesis.


Assuntos
Leishmania major/crescimento & desenvolvimento , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Linfócitos/imunologia , Imunidade Adaptativa , Animais , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Leishmania major/genética , Camundongos Endogâmicos BALB C
17.
JCI Insight ; 4(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593552

RESUMO

High levels of circulating miR-16 in the serum of multiple myeloma (MM) patients are independently associated with longer survival. Although the tumor suppressor function of intracellular miR-16 in MM plasma cells (PCs) has been elucidated, its extracellular role in maintaining a nonsupportive cancer microenvironment has not been fully explored. Here, we show that miR-16 is abundantly released by MM cells through extracellular vesicles (EVs) and that differences in its intracellular expression as associated with chromosome 13 deletion (Del13) are correlated to extracellular miR-16 levels. We also demonstrate that EVs isolated from MM patients and from the conditioned media of MM-PCs carrying Del13 more strongly differentiate circulating monocytes to M2-tumor supportive macrophages (TAMs), compared with MM-PCs without this chromosomal aberration. Mechanistically, our data show that miR-16 directly targets the IKKα/ß complex of the NF-κB canonical pathway, which is critical not only in supporting MM cell growth, but also in polarizing macrophages toward an M2 phenotype. By using a miR-15a-16-1-KO mouse model, we found that loss of the miR-16 cluster supports polarization to M2 macrophages. Finally, we demonstrate the therapeutic benefit of miR-16 overexpression in potentiating the anti-MM activity by a proteasome inhibitor in the presence of MM-resident bone marrow TAM.


Assuntos
Células da Medula Óssea/metabolismo , Macrófagos/metabolismo , MicroRNAs/fisiologia , Mieloma Múltiplo/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Camundongos , Camundongos Knockout , MicroRNAs/genética , Mieloma Múltiplo/patologia , Microambiente Tumoral
18.
Int J Parasitol Drugs Drug Resist ; 10: 125-132, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31493763

RESUMO

Visceral leishmaniasis (VL) is associated with treatment complications due to the continued growth of resistant parasites toward currently available pathogen-directed therapeutics. To limit the emergence and combat resistant parasites there is a need to develop new anti-leishmanial drugs and alternative treatment approaches, such as host-directed therapeutics (HDTs). Discovery of new anti-leishmanial drugs including HDTs requires suitable in vitro assay systems. Herein, we modified and evaluated a series of resazurin assays against different life-stages of the VL causing parasite, Leishmania donovani to identify novel HDTs. We further analyzed the synergy of combinatorial interactions between traditionally used pathogen-directed drugs and HDTs for clearance of intracellular L. donovani. The inhibitory concentration at 50% (IC50) of the five evaluated therapies [amphotericin B (AMB), miltefosine, paromomycin, DNER-4, and AR-12 (OSU-03012)] was determined against promastigotes, extracellular amastigotes, and intracellular amastigotes of L. donovani via a resazurin-based assay and compared to image-based microscopy. Using the resazurin-based assay, all evaluated therapies showed reproducible anti-leishmanial activity against the parasite's different life-stages. These results were consistent to the traditional image-based technique. The gold standard of therapy, AMB, showed the highest potency against intracellular L. donovani, and was further evaluated for combinatorial effects with the HDTs. Among the combinations analyzed, pathogen-directed AMB and host-directed AR-12 showed a synergistic reduction of intracellular L. donovani compared to individual treatments. The modified resazurin assay used in this study demonstrated a useful technique to measure new anti-leishmanial drugs against both intracellular and extracellular parasites. The synergistic interactions between pathogen-directed AMB and host-directed AR-12 showed a great promise to combat VL, with the potential to reduce the emergence of drug-resistant strains.


Assuntos
Antiprotozoários/administração & dosagem , Quimioterapia Combinada/métodos , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Anfotericina B/administração & dosagem , Animais , Sinergismo Farmacológico , Interações Hospedeiro-Parasita/efeitos dos fármacos , Humanos , Leishmania donovani/crescimento & desenvolvimento , Leishmaniose Visceral/diagnóstico por imagem , Leishmaniose Visceral/parasitologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Fosforilcolina/administração & dosagem , Fosforilcolina/análogos & derivados , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem
19.
Future Med Chem ; 11(15): 1999-2018, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31390889

RESUMO

Parasitic infections are responsible for significant morbidity and mortality throughout the world. Management strategies rely primarily on antiparasitic drugs that have side effects and risk of drug resistance. Therefore, novel strategies are needed for treatment of parasitic infections. Host-directed therapy (HDT) is a viable alternative, which targets host pathways responsible for parasite invasion/survival/pathogenicity. Recent innovative combinations of genomics, proteomics and computational biology approaches have led to discovery of several host pathways that could be promising targets for HDT for treating parasitic infections. Herein, we review major advances in HDT for parasitic disease with regard to core regulatory pathways and their interactions.


Assuntos
Anti-Infecciosos/uso terapêutico , Doenças Parasitárias/tratamento farmacológico , Anti-Infecciosos/farmacologia , Anticorpos Monoclonais/uso terapêutico , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/patologia , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose/imunologia , Leishmaniose/patologia , Doenças Parasitárias/imunologia , Doenças Parasitárias/patologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Toxoplasmose/tratamento farmacológico , Toxoplasmose/patologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/fisiologia
20.
J Immunol ; 203(4): 789-794, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31253729

RESUMO

CXCR3, an X-linked gene, is subject to X chromosome inactivation (XCI), but it is unclear whether CXCR3 escapes XCI in immune cells. We determined whether CXCR3 escapes XCI in vivo, evaluated the contribution of allelic CXCR3 expression to the phenotypic properties of T cells during experimental infection with Leishmania, and examined the potential implications to sex differences in immune responses. We used a bicistronic CXCR3 dual-reporter mouse, with each CXCR3 allele linked to a green or red fluorescent reporter without affecting endogenous CXCR3 expression. Our results show that CXCR3 escapes XCI, biallelic CXCR3-expressing T cells produce more CXCR3 protein than monoallelic CXCR3-expressing cells, and biallelic CXCR3-expressing T cells produce more IFN-γ, IL-2, and CD69 compared with T cells that express CXCR3 from one allele during Leishmania mexicana infection. These results demonstrate that XCI escape by CXCR3 potentially contributes to the sex-associated bias observed during infection.


Assuntos
Receptores CXCR3/imunologia , Caracteres Sexuais , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Inativação do Cromossomo X/imunologia , Animais , Feminino , Infecções/imunologia , Masculino , Camundongos , Camundongos Mutantes , Receptores CXCR3/genética
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