RESUMO
Immune-modulating therapies have revolutionized the treatment of chronic diseases, particularly cancer. However, their success is restricted and there is a need to identify new therapeutic targets. Here, we show that natural killer cell granule protein 7 (NKG7) is a regulator of lymphocyte granule exocytosis and downstream inflammation in a broad range of diseases. NKG7 expressed by CD4+ and CD8+ T cells played key roles in promoting inflammation during visceral leishmaniasis and malaria-two important parasitic diseases. Additionally, NKG7 expressed by natural killer cells was critical for controlling cancer initiation, growth and metastasis. NKG7 function in natural killer and CD8+ T cells was linked with their ability to regulate the translocation of CD107a to the cell surface and kill cellular targets, while NKG7 also had a major impact on CD4+ T cell activation following infection. Thus, we report a novel therapeutic target expressed on a range of immune cells with functions in different immune responses.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Inflamação/imunologia , Células Matadoras Naturais/imunologia , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , Malária/imunologia , Proteínas de Membrana/metabolismo , Plasmodium/fisiologia , Animais , Células Cultivadas , Citotoxicidade Imunológica , Modelos Animais de Doenças , Exocitose , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Vesículas Secretórias/metabolismoRESUMO
In an area endemic with Indian visceral leishmaniasis (VL), we performed direct xenodiagnosis to evaluate the transmission of Leishmania donovani from patients with VL-human immunodeficiency virus (HIV) coinfection to the vector sandflies, Phlebotomus argentipes. Fourteen patients with confirmed VL-HIV coinfection, with a median parasitemia of 42 205 parasite genome/mL of blood, were exposed to 732 laboratory-reared pathogen-free female P argentipes sandflies on their lower arms and legs. Microscopy revealed that 16.66% (122/732) of blood-fed flies were xenodiagnosis positive. Notably, 93% (13/14) of the VL-HIV group infected the flies, as confirmed by quantitative polymerase chain reaction and/or microscopy, and were 3 times more infectious than those who had VL without HIV.
Assuntos
Coinfecção , Infecções por HIV , Leishmania donovani , Leishmaniose Visceral , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/complicações , Animais , Humanos , Índia/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Feminino , Adulto , Coinfecção/virologia , Coinfecção/epidemiologia , Coinfecção/parasitologia , Leishmania donovani/isolamento & purificação , Masculino , Phlebotomus/parasitologia , Phlebotomus/virologia , Doenças Endêmicas , Pessoa de Meia-Idade , Adulto Jovem , Xenodiagnóstico , Insetos Vetores/parasitologia , Insetos Vetores/virologia , AdolescenteRESUMO
INTRODUCTION: Post-kala-azar dermal leishmaniasis (PKDL) arises as a dermal complication following a visceral leishmaniasis (VL) infection. Current treatment options for PKDL are unsatisfactory, and there is a knowledge gap regarding the distribution of antileishmanial compounds within human skin. The present study investigated the skin distribution of miltefosine in PKDL patients, with the aim to improve the understanding of the pharmacokinetics at the skin target site in PKDL. METHODS: Fifty-two PKDL patients underwent treatment with liposomal amphotericin B (20â mg/kg) plus miltefosine (allometric dosing) for 21 days. Plasma concentrations of miltefosine were measured on study days 8, 15, 22 and 30, while a punch skin biopsy was taken on day 22. A physiologically based pharmacokinetic (PBPK) model was developed to evaluate the distribution of miltefosine into the skin. RESULTS: Following the allometric weight-based dosing regimen, median miltefosine concentrations on day 22 were 43.73â µg/g (IQR: 21.94-60.65â µg/g) in skin and 33.29â µg/mL (IQR: 25.9-42.58â µg/mL) in plasma. The median individual concentration ratio of skin to plasma was 1.19 (IQR: 0.79-1.9). In 87% (45/52) of patients, skin exposure was above the suggested EC90 PK target of 10.6â mg/L associated with in vitro susceptibility. Simulations indicated that the residence time of miltefosine in the skin would be more than 2-fold longer than in plasma, estimated by a mean residence time of 604 versus 266 hours, respectively. CONCLUSION: This study provides the first accurate measurements of miltefosine penetration into the skin, demonstrating substantial exposure and prolonged retention of miltefosine within the skin. These findings support the use of miltefosine in cutaneous manifestations of leishmaniasis. In combination with parasitological and clinical data, these results are critical for the future optimization of combination therapies with miltefosine in the treatment of PKDL.
Assuntos
Anfotericina B , Antiprotozoários , Leishmaniose Cutânea , Leishmaniose Visceral , Fosforilcolina , Pele , Humanos , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacocinética , Fosforilcolina/administração & dosagem , Fosforilcolina/uso terapêutico , Antiprotozoários/farmacocinética , Antiprotozoários/administração & dosagem , Antiprotozoários/uso terapêutico , Masculino , Adulto , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Feminino , Pele/parasitologia , Leishmaniose Visceral/tratamento farmacológico , Pessoa de Meia-Idade , Adulto Jovem , Anfotericina B/farmacocinética , Anfotericina B/uso terapêutico , Anfotericina B/administração & dosagem , Adolescente , Ásia MeridionalRESUMO
Aneuploidy causes system-wide disruptions in the stochiometric balances of transcripts, proteins, and metabolites, often resulting in detrimental effects for the organism. The protozoan parasite Leishmania has an unusually high tolerance for aneuploidy, but the molecular and functional consequences for the pathogen remain poorly understood. Here, we addressed this question in vitro and present the first integrated analysis of the genome, transcriptome, proteome, and metabolome of highly aneuploid Leishmania donovani strains. Our analyses unambiguously establish that aneuploidy in Leishmania proportionally impacts the average transcript- and protein abundance levels of affected chromosomes, ultimately correlating with the degree of metabolic differences between closely related aneuploid strains. This proportionality was present in both proliferative and non-proliferative in vitro promastigotes. However, as in other Eukaryotes, we observed attenuation of dosage effects for protein complex subunits and in addition, non-cytoplasmic proteins. Differentially expressed transcripts and proteins between aneuploid Leishmania strains also originated from non-aneuploid chromosomes. At protein level, these were enriched for proteins involved in protein metabolism, such as chaperones and chaperonins, peptidases, and heat-shock proteins. In conclusion, our results further support the view that aneuploidy in Leishmania can be adaptive. Additionally, we believe that the high karyotype diversity in vitro and absence of classical transcriptional regulation make Leishmania an attractive model to study processes of protein homeostasis in the context of aneuploidy and beyond.
Assuntos
Leishmania donovani , Proteoma , Aneuploidia , Proteínas de Choque Térmico/genética , Humanos , Cariótipo , Leishmania donovani/genética , Peptídeo Hidrolases/genética , Proteoma/genéticaRESUMO
Addressing the complex challenge of healing of bacterially infected wounds, this study explores the potential of lipid nanomaterials, particularly advanced ultradeformable particles (UDPs), to actively influence the wound microenvironment. The research introduces a novel therapeutic approach utilizing silver sulfadiazine (SSD) coupled with vitamin E (VE) delivered through UDPs (ethosomes/transferosomes/transethosomes). Comparative physicochemical characterization of these nanosized drug carriers reveals the superior stability of transethosomes, boasting a zeta potential of -36.5 mV. This method demonstrates reduced side effects compared to conventional therapies, with almost 90% SSD and 72% VE release achieved in wound pH in a sustained manner. Cytotoxicity assessment shows 60% cell viability even at the highest concentration (175 µg/mL), while hemolysis test demonstrates RBC lysis below 5% at a concentration of 250 µg/mL. Vitamin E-SSD-loaded transethosomes (VSTEs) significantly enhance cellular migration and proliferation, achieving 95% closure within 24 h, underscoring their promising efficacy. The synergistic method effectively reduces bacterial burden, evidenced by an 80% reduction in Escherichia coli and Staphylococcus aureus within the wound microenvironment. This approach offers a promising strategy to address complications associated with skin injuries.
Assuntos
Portadores de Fármacos , Escherichia coli , Staphylococcus aureus , Vitamina E , Vitamina E/química , Portadores de Fármacos/química , Humanos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Sulfadiazina de Prata/farmacologia , Sulfadiazina de Prata/química , Sulfadiazina de Prata/uso terapêutico , Sulfadiazina de Prata/administração & dosagem , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Animais , Sistemas de Liberação de Medicamentos , Sobrevivência Celular/efeitos dos fármacosRESUMO
Sexual dysfunction (SD) is a common, yet under-reported non-motor symptom of PD. Common sexual symptoms among male PD patients include erectile dysfunction, premature ejaculation, and decreased sexual desire. Few research papers have examined sexual dysfunction in PD, especially in YOPD male patients, and there is no Indian research study on sexual dysfunction in YOPD. In this study, we determined the frequency of sexual dysfunction in men with YOPD, and its correlation with other motor and NMS. This prospective cross-sectional study was conducted on YOPD males who presented to the Department of Neurology, NIMHANS, Bangalore, India, from May 2021 to April 2023. The diagnosis of YOPD was made based on MDS criteria for IPD 2015. Sexual functions were evaluated by ASEX, PEDT, QUIP-RS, and sex hormone assay. The patients also underwent other motor and non-motor assessments. Statistical analysis was done using SPSS version 22.0. The study was funded by the PDMD fund. This study included 62 male YOPD patients. The mean age of cases was 44.74 ± 8.54 years. The mean duration of symptoms was 8.45 ± 6.23 years. 43.5% of the cases of PD were Akinetic rigid type. By ASEX Score grading, 46.8% of the cases had erectile dysfunction and 71% of the cases of YOPD had premature ejaculation by PEDT Score grading. 9.7% of the cases had hypersexuality by QUIP-RS. Duration of YOPD was a better predictor of Erectile Dysfunction and premature ejaculation when compared with other variables. SD was related to anxiety and depression and it had a negative impact on the patient's health-related quality of life (HR-QoL). SD should be investigated and treated as an integral part of the neurological assessment in YOPD.
Assuntos
Disfunção Erétil , Doença de Parkinson , Ejaculação Precoce , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Ejaculação Precoce/epidemiologia , Ejaculação Precoce/etiologia , Qualidade de Vida , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia , Doença de Parkinson/diagnóstico , Estudos Transversais , Estudos Prospectivos , ÍndiaRESUMO
Apolipoprotein E (ApoE) has been associated with several diseases including Parkinson's disease, Alzheimer's and multiple sclerosis. ApoE also has documented immunomodulatory functions. We investigated gene expression in circulating monocytes and in bone marrows of patients with visceral leishmaniasis (VL) living in an endemic area in Bihar, India, and contrasted these with control healthy subjects or other diagnostic bone marrows from individuals in the same region. Samples from VL patients were obtained prior to initiating treatment. Our study revealed significant upregulated expression of the apoE transcript in patients with VL. Furthermore, the levels of ApoE protein were elevated in serum samples of subjects with VL compared with healthy endemic controls. These observations may provide clues regarding the complex interactions between lipid metabolism and immunoregulation of infectious and inflammatory diseases.
Assuntos
Apolipoproteínas E , Leishmaniose Visceral , Monócitos , Regulação para Cima , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Apolipoproteínas E/genética , Medula Óssea , Índia/epidemiologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Monócitos/imunologiaRESUMO
BACKGROUND: Post kala-azar dermal leishmaniasis (PKDL) is a consequential dermal manifestation of visceral leishmaniasis (VL), serving as a parasite reservoir. The traditional diagnostic approach, which requires an invasive skin biopsy is associated with inherent risks and necessitates skilled healthcare practitioners in sterile settings. There is a critical need for a rapid, less invasive method for Leishmania detection. The main objective of this study was to evaluate and compare the diagnostic efficacy of PCR and qPCR in detecting PKDL, utilizing both skin and blood samples and to assess the utility of blood samples for molecular diagnosis. METHODS AND RESULTS: 73 individuals exhibiting clinical symptoms of PKDL and who had tested positive for rK39 rapid diagnostic test (RDT) were enrolled in this study. For the diagnosis of PKDL, both PCR and real-time quantitative PCR (qPCR), employing SYBR Green and TaqMan assays, were performed on blood and skin matched samples. qPCR results using both TaqMan and SYBR Green assay, indicated higher parasite loads in the skin compared to blood, as evident by the Ct values. Importantly, when blood samples were used for PKDL diagnosis by qPCR, an encouraging sensitivity of 69.35% (TaqMan assay) and 79.36% (SYBR Green) were obtained, compared to 8.2% with conventional PCR. CONCLUSION: The findings of the study suggest the potential utility of blood for molecular diagnosis by qPCR, offering a less invasive alternative to skin biopsies in field setting for the early detection of parasitaemia in PKDL patients and effective management and control of the disease.
Assuntos
Leishmaniose Cutânea , Leishmaniose Visceral , Reação em Cadeia da Polimerase em Tempo Real , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Masculino , Feminino , Adulto , Adolescente , Pele/parasitologia , Pele/patologia , Sensibilidade e Especificidade , Pessoa de Meia-Idade , Carga Parasitária/métodos , Técnicas de Diagnóstico Molecular/métodos , Adulto Jovem , Criança , DNA de Protozoário/genética , DNA de Protozoário/sangueRESUMO
Gorlin-Goltz syndrome, also known as Gorlin syndrome, basal cell nevus syndrome, and nevoid basal cell carcinoma syndrome, is an autosomal dominant genetic disorder. Its hallmark is an early onset of basal cell carcinoma. Additionally, the syndrome is characterized by a spectrum of distinct clinical attributes encompassing oral, skeletal, ophthalmic, neurological, and developmental aberrations. This condition arises due to anomalies in the Hedgehog signaling pathway, leading to constant pathway activity and uncontrolled growth of tumor cells. Early identification of the disorder through available diagnostic methods and clinical and radiological findings is crucial for accurate diagnosis, which subsequently leads to the formulation of an effective treatment regimen. The purpose of this case report is to discuss the role of a dentist in early detection based on various author-prescribed criteria and the need for a multidisciplinary approach to the treatment of patients with this syndrome.
Assuntos
Síndrome do Nevo Basocelular , Proteínas Hedgehog , Humanos , Síndrome do Nevo Basocelular/diagnóstico , Síndrome do Nevo Basocelular/genéticaRESUMO
Amphiregulin (AREG), which acts as one of the ligands for epidermal receptor growth factor receptor (EGFR), plays a crucial role in tissue repair, inflammation, and immunity. AREG is synthesized as membrane-anchored pre-protein, and is excreted after proteolytic cleavage, and serves as an autocrine or paracrine factor. After engagement with the EGFR, AREG triggers a cascade of signaling events required for many cellular physiological processes including metabolism, cell cycle, and proliferation. Under different inflammatory and pathogenic conditions, AREG is expressed by various activated immune cells that orchestrate both tolerance and host resistance mechanisms. Several factors including xenobiotics, cytokines, and inflammatory lipids have been shown to trigger AREG gene expression and release. In this review, we discuss the structure, function, and regulation of AREG, its role in tissue repair, inflammation, and homeostasis as well as the potential of AREG as a biomarker and therapeutic target.
Assuntos
Receptores ErbB , Transdução de Sinais , Anfirregulina/genética , Anfirregulina/metabolismo , Biomarcadores , Receptores ErbB/metabolismo , Humanos , Inflamação/genéticaRESUMO
Visceral leishmaniasis (VL) is the deadliest form of leishmaniasis without a safer treatment option. This study implies drug repurposing to find a novel antileishmanial compound, namely febrifugine dihydrochloride (FFG) targeting Leishmania antioxidant system. Starting with virtual screening revealed the high binding affinity and lead likeness of FFG against the trypanothione reductase (TR) enzyme of Leishmania donovani, followed by experimental validation. The promastigotes inhibition assay gave the IC50 concentration of FFG and Miltefosine (positive control) as 7.16 ± 1.39 nM and 11.41 ± 0.29 µM, respectively. Their CC50 was found as 451 ± 12.73 nM and 135.9 ± 5.94 µM, respectively. FFG has been shown to increase the reactive oxygen species (ROS), leading to apoptosis-like cell death among L. donovani promastigotes. Spleen touch biopsy resulted in 62% and 55% decreased parasite load with FFG and miltefosine treatment, respectively. Cytokine profiling has shown an increased proinflammatory cytokine response post-FFG treatment. Moreover, FFG is safe on the liver toxicity parameter in mice post-treatment.
Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Animais , Antiprotozoários/uso terapêutico , Antiprotozoários/toxicidade , Citocinas/metabolismo , Leishmaniose Visceral/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Piperidinas , QuinazolinasRESUMO
Visceral leishmaniasis (VL; Leishmania donovani) cases produce interferon-γ and tumor necrosis factor in response to soluble leishmanial antigen (SLA) in whole-blood assays. Using transcriptional profiling, we demonstrate the impact of interleukin-10 (IL-10), a cytokine implicated in VL, on this response. SLA stimulation identified 28 differentially expressed genes (DEGs), 17/28 in a single network with TNF as hub. SLA plus anti-IL-10 produced 454 DEGs, 292 in a single network with TNF, IFNG, NFKBIA, IL6, and IL1B as hubs in concert with a remarkable chemokine/cytokine storm. Our data demonstrate the singular effect of IL-10 as a potent immune modulator in VL.
Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Interleucina-10/imunologia , Leishmaniose Visceral/imunologia , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/genética , Antígenos de Protozoários/sangue , Citocinas/imunologia , Expressão Gênica , Humanos , Interferon gama/imunologia , Leishmania donovani/imunologia , Fator de Necrose Tumoral alfaRESUMO
BACKGROUND: Antimonial drugs have long been the mainstay to treat visceral leishmaniasis. Their use has been discontinued in the Indian subcontinent because of drug resistance, but they are still clinically useful elsewhere. The goal of this study was to find markers of antimony resistance in Leishmania donovani clinical isolates and validate experimentally their role in resistance. METHODS: The genomes of sensitive and antimony-resistant clinical isolates were sequenced. The role of a specific gene in contributing to resistance was studied by CRISPR-Cas9-mediated gene editing and intracellular drug sensitivity assays. RESULTS: Both gene copy number variations and single nucleotide variants were associated with antimony resistance. A homozygous insertion of 2 nucleotides was found in the gene coding for the aquaglyceroporin AQP1 in both resistant isolates. Restoring the wild-type AQP1 open reading frame re-sensitized the 2 independent resistant isolates to antimonials. Alternatively, editing the genome of a sensitive isolate by incorporating the 2-nucleotide insertion in its AQP1 gene led to antimony-resistant parasites. CONCLUSIONS: Through genomic analysis and CRISPR-Cas9-mediated genome editing we have proven the role of the AQP1 mutations in antimony clinical resistance in L. donovani.
Assuntos
Antiprotozoários , Aquagliceroporinas , Leishmania donovani , Leishmaniose Visceral , Antimônio/farmacologia , Antiprotozoários/farmacologia , Aquagliceroporinas/genética , Variações do Número de Cópias de DNA , Resistência a Medicamentos/genética , Humanos , Leishmania donovani/genética , MutaçãoRESUMO
The countries in the Indian subcontinent have reported a dramatic decline in visceral leishmaniasis (VL) cases. However, the presence of the parasite reservoir in the form of post-kala-azar dermal leishmaniasis (PKDL), a dermal sequel of VL, is a hurdle in attaining VL elimination. Presently employed clinical specimens for the diagnosis of PKDL include skin biopsy specimens and slit skin smears. In this study, the use of blood as a clinical specimen was investigated in different manifestations of PKDL in India. This is a bicentric study (National Institute of Pathology, Indian Council of Medical Research [ICMR], New Delhi, and Institute of Medical Sciences [IMS], Banaras Hindu University, Varanasi), with 215 participants (120 PKDL patients and 95 controls). Highly sensitive quantitative real-time PCR (Q-PCR) and field-deployable loop-mediated isothermal amplification (LAMP) were employed using blood samples for diagnosis. Promising sensitivities of 77.50% (95% confidence interval [CI], 69.24 to 84.05%) for Q-PCR and 70.83% (95% CI, 62.16 to 78.22%) for LAMP were obtained for the diagnosis of PKDL. Further, enhanced sensitivities of 83.33% (95% CI, 71.28 to 90.98%) and 77.78% (95% CI, 65.06 to 86.80%) for Q-PCR and LAMP, respectively, were recorded for the detection of macular cases. The study revealed an inverse correlation between the parasite load estimated in slit and blood samples, thereby favoring the use of blood for the diagnosis of the macular variant, which may be missed due to scant parasite loads in the slit. This study is the first to propose the promising potential of blood as a clinical specimen for accurate diagnosis of PKDL, which would aid in fast-tracking VL elimination.
Assuntos
Leishmania donovani , Leishmaniose Cutânea , Leishmaniose Visceral , Humanos , Índia , Leishmania donovani/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Visceral/diagnóstico , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Visceral leishmaniasis (VL) is a potentially fatal parasitic disease causing high morbidity and mortality in developing countries. Vaccination is considered the most effective and powerful tool for blocking transmission and control of diseases. However, no vaccine is available so far in the market for humans. In the present study, we characterized the hypothetical protein LDBPK_252400 of Leishmania donovani (LdHyP) and explored its prophylactic behavior as a potential vaccine candidate against VL. We found reduced hepato-splenomegaly along with more than 50% parasite reduction in spleen and liver after vaccination in mice. Protection in vaccinated mice after the antigen challenge correlated with the stimulation of antigen specific IFN-γ expressing CD4+T cell (~4.6 fold) and CD8+T cells (~2.1 fold) in vaccinated mice in compared to infected mice, even after 2-3 months of immunization. Importantly, antigen-mediated humoral immunity correlated with high antigen specific IgG2/IgG1 responses in vaccinated mice. In vitro re-stimulation of splenocytes with LdHyP enhances the expression of TNF-α, IFN-γ, IL-12 and IL-10 cytokines along with lower IL-4 cytokine and IL-10/IFN-γ ratio in vaccinated mice. Importantly, we observed ~3.5 fold high NO production through activated macrophages validates antigen mediated cellular immunity induction, which is critical in controlling infection progression. These findings suggest that immunization with LdHyP mount a very robust immunity (from IL-10 towards TFN-γ mediated responses) against L. donovani infection and could be explored further as a putative vaccine candidate against VL.
Assuntos
Vacinas contra Leishmaniose/imunologia , Leishmaniose Visceral/tratamento farmacológico , Animais , Antígenos de Protozoários/imunologia , Citocinas/imunologia , Imunidade Celular/imunologia , Imunização/métodos , Leishmania donovani/imunologia , Leishmania donovani/patogenicidade , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , Vacinação/métodosRESUMO
The protozoan parasite L. donovani resides inside macrophages as amastigotes and inflicts a potentially lethal disease visceral leishmaniasis (VL). Due to absence of a vaccine, chemotherapy with antimonials, amphotericin B, miltefosine or paromomycin remains the only option for treating VL. Prolonged treatment with a single drug resulted in parasite strains resistant to each of these drugs. As immuno-suppression characterizes the disease, we examined whether eliciting immunosuppressive cytokines is a mechanism of manifestation of drug-resistance. We infected BALB/c mice with the clinical isolates of L. donovani- BHU1066 (sensitive), NS2 (antimony-resistant), BHU1064 (miltefosine-resistant), BHU919 (Amphotericin B-resistant) and BHU1020 (paromomycin-resistant)- from the respective drug-unresponsive patients and assessed splenic parasite load and production of pro-inflammatory and anti-inflammatory cytokines. Although the splenic parasite loads in the drug-resistant L. donovani-infected BALB/c mice were higher than that observed in the drug-sensitive parasites-infected mice, the cytokine profiles were not significantly different between these two sets of mice. The drug-resistance in L. donovani results from innate drug modulation but perhaps not from host immune-suppressive cytokines.
Assuntos
Resistência a Medicamentos/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Anfotericina B/imunologia , Animais , Antimônio/imunologia , Citocinas/imunologia , Terapia de Imunossupressão/métodos , Leishmaniose Visceral/parasitologia , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Fosforilcolina/análogos & derivados , Fosforilcolina/imunologia , Proteínas de Protozoários/imunologiaRESUMO
Blast-induced traumatic brain injury (bTBI) is a rising health concern of soldiers deployed in modern-day military conflicts. For bTBI, blast wave loading is a cause, and damage incurred to brain tissue is the effect. There are several proposed mechanisms for the bTBI, such as direct cranial entry, skull flexure, thoracic compression, blast-induced acceleration, and cavitation that are not mutually exclusive. So the cause-effect relationship is not straightforward. The efficiency of protective headgears against blast waves is relatively unknown as compared with other threats. Proper knowledge about standard problem space, underlying mechanisms, blast reconstruction techniques, and biomechanical models are essential for protective headgear design and evaluation. Various researchers from cross disciplines analyze bTBI from different perspectives. From the biomedical perspective, the physiological response, neuropathology, injury scales, and even the molecular level and cellular level changes incurred during injury are essential. From a combat protective gear designer perspective, the spatial and temporal variation of mechanical correlates of brain injury such as surface overpressure, acceleration, tissue-level stresses, and strains are essential. This paper outlines the key inferences from bTBI studies that are essential in the protective headgear design context.
Assuntos
Dispositivos de Proteção da CabeçaRESUMO
HLA-DRB1 is the major genetic risk factor for visceral leishmaniasis (VL). We used SNP2HLA to impute HLA-DRB1 alleles and SNPTEST to carry out association analyses in 889 human cases and 977 controls from India. NetMHCIIpan 2.1 was used to map epitopes and binding affinities across 49 Leishmania vaccine candidates, as well as across peptide epitopes captured from dendritic cells treated with crude Leishmania Ag and identified using mass spectrometry and alignment to amino acid sequences of a reference Leishmania genome. Cytokines were measured in peptide-stimulated whole blood from 26 cured VL cases and eight endemic healthy controls. HLA-DRB1*1501 and DRB1*1404/DRB1*1301 were the most significant protective and risk alleles, respectively, with specific residues at aa positions 11 and 13 unique to protective alleles. We observed greater peptide promiscuity in sequence motifs for 9-mer core epitopes predicted to bind to risk (*1404/*1301) compared with protective (*1501) DRB1 alleles. There was a higher frequency of basic amino acids in DRB1*1404/*1301-specific epitopes compared with hydrophobic and polar amino acids in DRB1*1501-specific epitopes at anchor residues pocket 4 and pocket 6, which interact with residues at DRB1 positions 11 and 13. Cured VL patients made variable, but robust, IFN-γ, TNF, and IL-10 responses to 20-mer peptides based on captured epitopes, with peptides based on DRB1*1501-captured epitopes resulting in a higher proportion (odds ratio 2.23, 95% confidence interval 1.17-4.25, p = 0.017) of patients with IFN-γ/IL-10 ratios > 2-fold compared with peptides based on DRB1*1301-captured epitopes. Our data provide insight into the molecular mechanisms underpinning the association of HLA-DRB1 alleles with risk versus protection in VL in humans.
Assuntos
Epitopos/imunologia , Cadeias HLA-DRB1/imunologia , Leishmaniose Visceral/imunologia , Adolescente , Adulto , Alelos , Criança , Feminino , Humanos , Interleucina-10/imunologia , Masculino , Pessoa de Meia-Idade , Ligação Proteica/imunologia , Adulto JovemRESUMO
Control of visceral leishmaniasis (VL) caused by Leishmania donovani requires interferon-γ production by CD4+ T cells. In VL patients, antiparasitic CD4+ T-cell responses are ineffective for unknown reasons. In this study, we measured the expression of genes associated with various immune functions in these cells from VL patients and compared them to CD4+ T cells from the same patients after drug treatment and from endemic controls. We found reduced GATA3, RORC, and FOXP3 gene expression in CD4+ T cells of VL patients, associated with reduced Th2, Th17, and FOXP3+CD4+ T regulatory cell frequencies in VL patient blood. Interleukin 2 (IL-2) was an important upstream regulator of CD4+ T cells from VL patients, and functional studies demonstrated the therapeutic potential of IL-2 for improving antiparasitic immunity. Together, these results provide new insights into the characteristics of CD4+ T cells from VL patients that can be used to improve antiparasitic immune responses.