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1.
Mycoses ; 67(4): e13722, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606896

RESUMO

BACKGROUND: Two approaches are used to manage invasive fungal disease (IFD) in febrile neutropenic patients viz. empirical therapy (without attempting to confirm the diagnosis), or pre-emptive therapy (after screening tests for IFD). OBJECTIVE: This systematic review was undertaken to compare these approaches in children. METHODS: We searched PubMed, EMBASE, Cochrane Library, Scopus, Web of Science, CINAHL, Clinical Trial Registries and grey literature, for randomized controlled trials (RCT) comparing empirical versus pre-emptive antifungal therapy in children with FN suspected to have IFD. We used the Cochrane Risk of bias 2 tool for quality assessment, and evaluated the certainty of evidence using the GRADE approach. RESULTS: We identified 7989 citations. Stepwise screening identified only one relevant RCT that administered empirical (n = 73) or pre-emptive (n = 76) antifungal therapy. There were no significant differences in all-cause mortality (RR 1.56, 95% CI: 0.46, 5.31), IFD mortality (RR 1.04, 95% CI:0.15, 7.20) and other clinically important outcomes such as duration of fever, duration of hospitalization and proportion requiring ICU admission. There were no safety data reported. The number of days of antifungal therapy was significantly lower in the pre-emptive therapy arm. The certainty of evidence for all outcomes was 'moderate'. CONCLUSIONS: This systematic review highlighted the paucity of data, comparing empirical versus pre-emptive antifungal therapy in children with febrile neutropenia having suspected invasive fungal disease. Data from a single included trial suggests that both approaches may be comparable in research settings. Robust trials are warranted to address the gap in existing knowledge about the optimal approach in clinical practice.


Assuntos
Antifúngicos , Neutropenia Febril , Infecções Fúngicas Invasivas , Criança , Humanos , Antifúngicos/uso terapêutico , Neutropenia Febril/tratamento farmacológico , Hospitalização , Infecções Fúngicas Invasivas/tratamento farmacológico , Infecções Fúngicas Invasivas/prevenção & controle
2.
Front Oncol ; 14: 1269211, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469233

RESUMO

Purpose: Isolating circulating tumour cells (CTCs) from the blood is challenging due to their low abundance and heterogeneity. Limitations of conventional CTC detection methods highlight the need for improved strategies to detect and isolate CTCs. Currently, the Food and Drug Administration (FDA)-approved CellSearch™ and other RUO techniques are not available in India. Therefore, we wanted to develop a flexible CTC detection/isolation technique that addresses the limitation(s) of currently available techniques and is suitable for various downstream applications. Methods: We developed a novel, efficient, user-friendly CTC isolation strategy combining density gradient centrifugation and immuno-magnetic hematogenous cell depletion with fluorescence-activated cell sorting (FACS)-based positive selection using multiple CTC-specific cell-surface markers. For FACS, a stringent gating strategy was optimised to exclude debris and doublets by side scatter/forward scatter (SSC/FSC) discriminator, remove dead cells by 4',6-diamidino-2-phenylindole (DAPI) staining, and eliminate non-specific fluorescence using a "dump" channel. APC-labelled anti-CD45mAB was used to gate remaining hematogenous cells, while multiple epithelial markers (EpCAM, EGFR, and Pan-Cytokeratin) and an epithelial-mesenchymal transition (EMT) marker (Vimentin) labelled with fluorescein isothiocyanate (FITC) were used to sort cancer cells. The technique was initially developed by spiking Cal 27 cancer cells into the blood of healthy donors and then validated in 95 biopsy-proven oral squamous cell carcinoma (OSCC) patients. CTCs isolated from patients were reconfirmed by Giemsa staining, immuno-staining, and whole transcriptome amplification (WTA), followed by qRT-PCR. In vitro culture and RNA sequencing (RNA-Seq) were also performed to confirm their suitability for various downstream applications. Results: The mean detection efficiency for the Cal 27 tongue cancer cells spiked in the whole blood of healthy donors was 32.82% ± 12.71%. While ~75% of our patients (71/95) had detectable CTCs, the CTC positivity was independent of the TNM staging. The isolated potential cancer cells from OSCC patients were heterogeneous in size. They expressed different CTC-specific markers in various combinations as identified by qRT-PCR after WTA in different patients. Isolated CTCs were also found to be suitable for downstream applications like short-term CTC culture and RNA-Seq. Conclusion: We developed a sensitive, specific, flexible, and affordable CTC detection/isolation technique, which is scalable to larger patient cohorts, provides a snapshot of CTC heterogeneity, isolates live CTCs ready for downstream molecular analysis, and, most importantly, is suitable for developing countries.

3.
Iran J Otorhinolaryngol ; 36(1): 361-363, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38259690

RESUMO

Introduction: An unusual nasopharyngeal foreign body in a very young child with no clinical symptoms is a rare case presentation. Case Report: A nine-month-old child presented with a suspected history of foreign body ingestion without any clue to the parents about the nature of the foreign body. X-ray of the nasopharynx revealed a sharp unusual metallic "Louis Vuitton" shoe logo that the child had accidentally inserted into the nasopharynx via the oral cavity while playing. Foreign body was removed under general anesthesia without complications. Conclusion: X-ray nasopharynx should be included in the examination of a suspected case of foreign body ingestion, as an unusual shape of foreign body can even produce no clinical symptoms but still pose a potential life threat due to its dislodgement into the airway if missed or delayed.

4.
Pediatr Dermatol ; 40(6): 1112-1114, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37160270

RESUMO

Addisonian pigmentation usually presents with nonspecific symptoms and signs, which are often ignored or misdiagnosed as a sign of other more common diseases. We present a case of 12-year-old child in whom diffuse Addisonian hyperpigmentation of skin was associated with underlying acute lymphoblastic leukemia (B-type), a rare paraneoplastic phenomenon in hematological malignancies.


Assuntos
Hiperpigmentação , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Hiperpigmentação/etiologia , Pele , Pigmentação
5.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 133-139, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37206774

RESUMO

Ear ailments in children are a major public health problem in India. This systematic review and meta-analysis aim to quantitatively pool the epidemiologic evidence on the prevalence of all forms of otitis media in children of India. In this review PRISMA guidelines (preferred reporting items for systematic reviews and meta-analysis) were followed. We did extensive literature search in PubMed, Embase, Cinahl and Web of Science to identify relevant community based cross sectional studies that investigated the prevalence of otitis media in children of India. We used STATA version 16.0 software to perform meta-analysis. Six studies reporting the prevalence of otitis media in children were included in the final analysis. Based on the results of the random-effects sub-group meta-analysis model, the pooled estimated prevalence of Chronic suppurative otitis media in children of India was 3.78% (95% CI 2.72-4.84), Otitis media with effusion was found to be 2.68% (95% CI 1.80, 3.55) and Acute suppurative otitis media to be 0.55 (95% CI 0.32, 0.78). This review suggests substantial otitis media related disease burden in children of India. But due to lack of epidemiological studies, the actual disease burden remains concealed. It is imperative to promote more epidemiological studies that will aid policy makers in recommendation of preventive, diagnostic and treatment strategies for this disease.

7.
Scand J Immunol ; 97(5): e13262, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36853017

RESUMO

Reservoirs of HIV remain a major obstacle to the complete eradication of virus despite regular anti-retroviral therapy (ART). Memory stem cells (Tscm), one of the major reservoirs, are relatively less studied owing to their presence in lower numbers and inaccessible anatomical locations. We have evaluated the molecular characteristics of Tscms in patients with ART interruption (n = 15) versus patients on uninterrupted ART (n = 12) using flow cytometry. RNA sequencing was done in the sorted Tscms to study the differential gene expression. Patients with ART interruption had significantly lower baseline CD4+T-cell counts and high viral loads as compared to patients on ART. The former group had significantly higher frequency of CD4+ and CD8+Tscms with a higher expression of PD-1 on CD8+Tscms. The transcriptome profile of Tscm was significantly different among the patient groups. The main pathways were cellular and metabolic pathways, cellular development pathways, cell differentiation and negative regulation of cellular migratory pathways. An increased yet dysfunctional CD8+ memory stem cells describe HIV-1-infected patients with break-in ART and a distinct transcriptional signature of CD4+ Tscm as compared to those of patients on ART. A more detailed understanding of the biology and dynamics of Tscm in future studies is warranted. Strategies to improve the functionality of the CD8+ Tscm will help these patients to tackle the outburst of viral replication that occurs after the cessation of therapy.


Assuntos
Antirretrovirais , Infecções por HIV , Células de Memória Imunológica , Células-Tronco , Interrupção do Tratamento , Adulto , Feminino , Humanos , Masculino , Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/dietoterapia , Infecções por HIV/virologia , Células de Memória Imunológica/virologia , Células-Tronco/virologia , Análise de Sequência de RNA
9.
Indian Pediatr ; 59(7): 563-569, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35869878

RESUMO

BACKGROUND: With wide clinical spectrum, multisystem inflammatory syndrome associated with coronavirus disease 2019 (COVID-19) in children (MIS-C) is a relatively novel condition occurring weeks to months' post SARS-CoV-2 infection. The aim was to systematically review data on clinical features, laboratory parameters and therapeutics of MIS-C from India. Methods: This systematic review was done as per the PRISMA guidelines, and quality assessment was done using NIH tool for case-series. A systematic search through databases yielded studies whose data was pooled to calculate the mean frequencies with standard deviation using GraphPad software. RESULTS: Screening of 2548 articles published till December, 2021, yielded 11 case-series. World Health Organization case definition was used widely. There was a slight preponderance of males (57%), median (IQR) age was 7 (6,7) years, 63% (n=305) required intensive care unit admissions, and mortality rate was 10% (n=261). Clinical features included fever, mucocutaneous features (72%), and gastrointestinal problems (62%) in majority. Widely used treatment was corticosteroids (76%) and intravenous immunoglobulin (62%) with other options depending on patient's state. An increased level of inflammatory markers and derangement in other parameters corroborated with disease status. Kawasaki disease like features, not reported in many studies, ranged from 4-76% of patients. CONCLUSION: MIS-C presents with a wide spectrum clinical features, increased inflammatory markers and managed as per the disease course and presentation. Future studies monitoring the long-term effects of MIS-C are recommended.


Assuntos
COVID-19 , Síndrome de Linfonodos Mucocutâneos , Biomarcadores , COVID-19/complicações , COVID-19/epidemiologia , Criança , Humanos , Masculino , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia
10.
J Trop Pediatr ; 68(2)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35137236

RESUMO

BACKGROUND: Depletion of CD4+ T-cells in the gut-associated lymphoid tissue is the hallmark of HIV infection, with only partial restoration by potent antiretroviral therapy (ART). Gut dysbiosis, together with disruption of mucosal integrity contributes to chronic immune activation that further exacerbates the disease. Data from randomized controlled trials in pediatric HIV patients have indicated potential of probiotics in complementing routine ART in managing HIV-associated gastrointestinal complications. We have systematically extracted data from these trials and performed meta-analysis to quantify the effect of probiotics on CD4+ T-cell counts and any adverse events associated with their supplementation. METHODS: A systematic search through multiple databases yielded three studies that were pooled using fixed-effect model. Risk of bias assessment was done by the Cochrane risk of bias tool and publication bias was assessed by Egger's test. RESULTS: Included studies had moderate risk of bias and Egger's statistics revealed no publication bias (p > 0.05). Pooled analysis showed significant improvement in CD4+ T-cell counts, with mean difference, 123.92 (95% CI: 104.36-143.48), p < 0.0001, no heterogeneity (I2=0) among the included trials. Subgroup analysis also depicted improvement in CD4+ T-cell counts irrespective of treatment duration, in both ART naïve and treated patients. No adverse effects with probiotic consumption were reported. CONCLUSIONS: Probiotics supplementation led to an improvement in CD4+ T-cell counts among HIV-infected children with no observed adverse effects. Despite the inherent limitations of included studies, our systematic review would justify more well-designed, large-scale trials in children, which may guide pediatricians on whether to incorporate probiotics as an adjunct therapy to routine ART.


HIV infection is associated with a progressive decline of CD4+ T-cell numbers and increase in viral load. To keep the virus replication in check, patients need to take the antiretroviral therapy life-long, which is not without gastrointestinal discomfort. Probiotics have already shown multiple benefits ranging from reduction in diarrhea, nausea and bloating besides replenishment of CD4+ T-cells numbers. Based on this background information, we have compiled the data on probiotics among HIV-infected children. A pooled analysis from randomized clinical trials revealed significant improvement in CD4+ T-cell counts in HIV-infected children without any adverse effects. However, we recommend large and well-designed trials in future that would help in forming a concrete and high quality evidence in this context.


Assuntos
Infecções por HIV , Probióticos , Adolescente , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Criança , Infecções por HIV/tratamento farmacológico , Humanos , Probióticos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
EXCLI J ; 19: 718-733, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636725

RESUMO

Hepatocellular carcinoma (HCC), with rising incidence rates, is the most commonly occurring malignancy of the liver that exerts a heavy disease burden particularly in developing countries. A dynamic cross-talk between immune cells and malignant cells in tumor microenvironment governs the hepatocarcinogenesis. Monitoring immune contexture as prognostic markers is quite relevant and essential to evaluate clinical outcomes and to envisage response to therapy. In this review, we present an overview of the prognostic value of various tumor infiltrating immune cells and the continually evolving immune checkpoints as novel biomarkers during HCC. Tumor infiltration by immune cells such as T cells, NK cells and dendritic cells is linked with improved prognosis and favorable outcome, while the intra-tumoral presence of regulatory T cells (Tregs) or myeloid derived suppressor cells (MDSCs) on the other hand is associated with poor clinical outcome. In addition to these, the overexpression of negative regulatory molecules on tumor cells also provides inhibitory signals to T cells and is associated with poor prognosis. The limitation of a single marker can be overcome by advanced prognostication models and algorithms that evaluate multiple prognostic factors and ultimately aid the clinician in improving the disease free and overall survival of HCC patients.

13.
Scand J Immunol ; 90(1): e12770, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31017304

RESUMO

Increasing evidence suggests a role of inflammation during the pathogenesis of osteoarthritis (OA). The local and systemic inflammation was studied in 33 patients of different KL grades, grade2 (n = 11), grade3 (n = 6) and grade4 (n = 16). The levels of cytokines, adipokines and matrix metalloproteinases (MMPs) were measured in serum and synovial fluid (SF) by flow cytometry and ELISA, respectively. The frequency of T cells and CD161 expression was measured by flow cytometry. The levels of IL-1ß, IL-6 and IL-10 were significantly higher in sera and SF of patients with OA as compared to healthy control's serum. Higher levels of MMP9 and leptin and lower levels of adiponectin were observed in SF as compared to serum. The MMP9 in SF and MMP13 levels in serum and SF decreased in KL grade 4 cases. In these patients, higher levels of leptin and lower levels of adiponectin were observed in SF versus patients of lower grades. There was increased infiltration of CD8+ T cells in SF of OA cases with decreased frequency in grade 4 cases. The expression of CD161 on T cells was significantly higher in SF than peripheral blood with significant upregulation in grade 4 patients. The CD161 expression had significant positive correlation with IL-17 in the serum of patients. The ROC curves of CD161 expression significantly distinguished grade 2 and grade 4 patients. Collectively, an elevated CD161 expression on T cells in circulation and synovial compartment clearly distinguished lower and higher grade patients warranting studies to assess its role as a contributing factor towards OA progression.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Inflamação/imunologia , Subfamília B de Receptores Semelhantes a Lectina de Células NK/metabolismo , Osteoartrite/imunologia , Membrana Sinovial/imunologia , Movimento Celular , Doença Crônica , Citocinas/metabolismo , Progressão da Doença , Feminino , Humanos , Ativação Linfocitária , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Regulação para Cima
14.
PLoS One ; 13(7): e0200644, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30020985

RESUMO

BACKGROUND AND AIM: Due to a dysregulated immune response, patients with acute-on-chronic liver failure (ACLF) have increased risk of infection and multi organ failure in comparison to compensated cirrhosis. The comparative data on the presence of 'immune paresis' in patients with ACLF and decompensated cirrhosis without ACLF is not available. Aim of the present study was to compare the immunological parameters in patients with decompensated cirrhosis with and without ACLF. METHODOLOGY: In a prospective study, 76 patients with decompensated cirrhosis with (n = 38) and without (n = 38) ACLF and 10 healthy controls (HC) were evaluated for monocytic human leukocyte antigen-antigen D Related (HLA-DR) expression, mean density of HLA-DR expressed on the surface of these cells, neutrophil oxidative burst (NOB) capacity and serum levels of cytokines (IL-1, IL-6, IL-8, IL10, IL-12, and TNF-α). RESULTS: Patients of decompensated cirrhosis with and without ACLF demonstrated significantly lower mean percentage of monocytes expressing HLA-DR and quantitative increase in the NOB after stimulation with PMA when compared to HC. However there was no difference in mean percentage of monocytes with HLA-DR expression (43.61±26.56% vs. 43.10±20.98%) (p = 0.91), mean density of HLA-DR expression on the surface (30.34±29.32 vs. 41.71±52.13) (p = 0.42) and quantitative increase in NOB after stimulation with PMA (16.55±11.91 vs. 17.24±16.18) (p = 0.47) amongst patients with decompensated cirrhosis with and without ACLF. Patients with ACLF had significantly higher pro-inflammatory and anti-inflammatory cytokines in comparison to patients with decompensated cirrhosis without ACLF. CONCLUSION: Patients with decompensated cirrhosis demonstrate a component of immune-paresis, however there is similar impairment in HLA-DR expression and NOB capacity in patients with and without ACLF. Both inflammatory and anti-inflammatory cytokines are increased in patients with ACLF in comparison to patients with decompensated cirrhosis without ACLF.


Assuntos
Citocinas/imunologia , Doença Hepática Terminal/imunologia , Fibrose/imunologia , Antígenos HLA-DR/imunologia , Falência Hepática Aguda/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Explosão Respiratória/imunologia , Adulto , Doença Hepática Terminal/patologia , Feminino , Fibrose/patologia , Humanos , Falência Hepática Aguda/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Neutrófilos/patologia
15.
Cytokine ; 91: 118-123, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28056393

RESUMO

Mechanisms of functional impairment of dendritic cells (DCs) during chronic HIV-1 infection are not well understood. In order to understand this phenomenon, we aimed to study the expression of negative regulators of cytokine signaling and correlate with DC exhaustion during chronic HIV-1 disease. Monocyte-derived DCs (mo-DCs) from 27 HIV-1 infected patients (CD4+ T-cell counts: 429±44 cells/µL, plasma viral load: Log103.9±1.0copies/ml) and 19 healthy controls (HCs) were stimulated ex vivo with TLR4 agonist, lipopolysaccharide (LPS) for 2days to evaluate their functional fitness. The expression of a set of genes associated with cytokine signaling was evaluated in a custom designed PCR array by Real-Time PCR. The mo-DCs from HIV-1 infected patients depicted functional exhaustion as evident by decreased allo-stimulation index (mean±SD: 10±6 vs. 24±16) (p<0.05), decreased cytokine production (pg/ml) (IL-12: 4.6±16 vs. 25±85; TNF-α: 128±279 vs. 286±544; IL-10: 6±12 vs. 13±20; IL-8: 10,688±11,748 vs. 17,470±125,049) and retained endocytosis (1.1±0.3 vs. 1.0±0.29) (p<0.05) even after LPS-stimulation, as compared to HCs. Significantly upregulated expression of SOCS-1 (mean±SD fold change: 2.2±2vs.0.8±0.6), SOCS-3 (6.3±7.4vs.1.4±0.4), PIAS-1 (1.6±0.1vs.1.0±0.3) and SHP-1 (0.8±0.4vs.0.4±0.2) correlated positively with PD-L1 expression in these DCs (Spearman's coefficient, SOCS-1: 0.63, SOCS-3: 1.0 and PIAS-1: 0.7) (p<0.05). The expression of these molecules trended positively with plasma viral load and negatively with CD4+ T-cell counts. These findings suggest that the upregulation of negative regulatory factors during chronic HIV disease have profound down-modulatory effects on DC functions and establishment of an overall exhausted state. Understanding mechanisms causing upregulation of these factors may lead to the design of new generation therapeutics based on silencing of their gene expression.


Assuntos
Citocinas/imunologia , Células Dendríticas/imunologia , Infecções por HIV/imunologia , Transdução de Sinais/imunologia , Adulto , Doença Crônica , Células Dendríticas/patologia , Feminino , Infecções por HIV/patologia , Humanos , Lipopolissacarídeos/toxicidade , Masculino , Transdução de Sinais/efeitos dos fármacos
16.
PLoS One ; 10(10): e0140852, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26492336

RESUMO

INTRODUCTION: Severely immunocompromised state during advanced stage of HIV-1 infection has been linked to functionally defective antigen presentation by dendritic cells (DCs). The molecular mechanisms behind DC impairment are still obscure. We investigated changes in DC function and association of key regulators of cytokine signaling during different stages of HIV-1 infection and following antiretroviral therapy (ART). METHODS: Phenotypic and functional characteristics of circulating myeloid DCs (mDCs) in 56 ART-naive patients (23 in early and 33 in advanced stage of disease), 36 on ART and 24 healthy controls were evaluated. Sixteen patients were studied longitudinally prior-to and 6 months after the start of ART. For functional studies, monocyte-derived DCs (Mo-DCs) were evaluated for endocytosis, allo-stimulation and cytokine secretion. The expression of suppressor of cytokine signaling (SOCS)-1 and other regulators of cytokine signaling was evaluated by real-time RT-PCR. RESULTS: The ability to respond to an antigenic stimulation was severely impaired in patients in advanced HIV-1 disease which showed partial recovery in the treated group. Mo-DCs from patients with advanced HIV-disease remained immature with low allo-stimulation and reduced cytokine secretion even after TLR-4 mediated stimulation ex-vivo. The cells had an increased expression of negative regulatory factors like SOCS-1, SOCS-3, SH2-containing phosphatase (SHP)-1 and a reduced expression of positive regulators like Janus kinase (JAK)2 and Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)1. A functional recovery after siRNA mediated silencing of SOCS-1 in these mo-DCs confirms the role of negative regulatory factors in functional impairment of these cells. CONCLUSIONS: Functionally defective DCs in advanced stage of HIV-1 infection seems to be due to imbalanced state of negative and positive regulatory gene expression. Whether this is a cause or effect of increased viral replication at this stage of disease, needs further investigation. The information may be useful in design of novel therapeutic targets for better management of disease.


Assuntos
Citocinas/metabolismo , Células Dendríticas/citologia , Infecções por HIV/metabolismo , Adulto , Estudos Transversais , Endocitose/fisiologia , Feminino , Infecções por HIV/patologia , Humanos , Teste de Cultura Mista de Linfócitos , Masculino , Células Mieloides/citologia , Células Mieloides/metabolismo , Transdução de Sinais/fisiologia , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo
17.
World J Hepatol ; 7(19): 2202-8, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26380045

RESUMO

Hepatitis C virus (HCV) infection causes tremendous morbidity and mortality with over 170 million people infected worldwide. HCV gives rise to a sustained, chronic disease in the majority of infected individuals owing to a failure of the host immune system to clear the virus. In general, an adequate immune response is elicited by an efficient antigen presentation by dendritic cells (DCs), the cells that connect innate and adaptive immune system to generate a specific immune response against a pathogen. However, HCV seems to dysregulate the activity of DCs, making them less proficient antigen presenting cells for the optimal stimulation of virus-specific T cells, hence interfering with an optimal anti-viral immune response. There are discordant reports on the functional status of DCs in chronic HCV infection (CHC), from no phenotypic or functional defects to abnormal functions of DCs. Furthermore, the molecular mechanisms behind the impairment of DC function are even so not completely elucidated during CHC. Understanding the mechanisms of immune dysfunction would help in devising strategies for better management of the disease at the immunological level and help to predict the prognosis of the disease in the patients receiving antiviral therapy. In this review, we have discussed the outcomes of the interaction of DCs with HCV and the mechanisms of DC impairment during HCV infection with its adverse effects on the immune response in the infected host.

18.
World J Hepatol ; 7(17): 2080-90, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26301050

RESUMO

Hepatocellular carcinoma (HCC) is primarily a malignancy of the liver, advancing from a damaged, cirrhotic liver to HCC. Globally, HCC is the sixth most prevalent cancer and the third-most prevalent reason for neoplastic disease-related deaths. A diverse array of infiltrating immunocytes regulates the development and progression of HCC, as is the case in many other cancers. An understanding of the various immune components during HCC becomes necessary so that novel therapeutic strategies can be designed to combat the disease. A dysregulated immune system (including changes in the number and/or function of immune cells, cytokine levels, and the expression of inhibitory receptors or their ligands) plays a key role in the development of HCC. Alterations in either the innate or adaptive arm of the immune system and cross-talk between them make the immune system tolerant to tumors, leading to disease progression. In this review, we have discussed the status and roles of various immune effector cells (e.g., dendritic cells, natural killer cells, macrophages, and T cells), their cytokine profile, and the chemokine-receptor axis in promoting or impeding HCC.

19.
J Acquir Immune Defic Syndr ; 54(5): 447-54, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20463584

RESUMO

BACKGROUND: Chronic HIV-1 infection is associated with excessive immune activation and immune exhaustion. We investigated the relationship of these 2 phenotypes and frequency of regulatory T cells (Tregs) in controlled and uncontrolled chronic HIV-1 infection. METHODS: Immune exhaustion marker PD-1, its ligand PD-L1, CD4CD25 FoxP3 Tregs, HLA-DR, and CD38 coexpression as activation markers were investigated in peripheral blood lymphocytes of 44 HIV-1-infected patients and 11 HIV-1-uninfected controls by multicolor flow cytometry. RESULTS: Activated and PD-1 expressing T cells were increased, and Tregs were decreased in HIV-1-infected patients as compared with controls, and alterations were greatest in viremic patients. The proportion of activated CD8 T cells exceeded activated CD4 T cells. Tregs had an inverse correlation with activated T cells and PD-1 expressing T cells. PD-L1 was highly expressed on monocytes and to a lesser extent on T lymphocytes of patients. These abnormalities partially reversed with virologic control after potent antiretroviral therapy. CONCLUSIONS: Immune exhaustion is a component of aberrant immune activation in chronic HIV-1 infection and is associated with loss of Tregs and ongoing virus replication. These defects are corrected partially with effective virologic control by potent antiretroviral therapy.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Ativação Linfocitária , Linfócitos T Reguladores/imunologia , Adulto , Antígenos CD/análise , Doença Crônica , Feminino , Citometria de Fluxo , Humanos , Masculino , Subpopulações de Linfócitos T/química , Subpopulações de Linfócitos T/imunologia
20.
Viral Immunol ; 23(1): 49-61, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20121402

RESUMO

We investigated in-vitro lymphoproliferative responses and T-cell subsets in 38 HIV-1-infected patients showing impaired restoration of CD4 T cells despite prolonged viral suppression (discordant), and in 42 HIV-1-infected patients showing positive immunological and virological responses to highly active antiretroviral therapy (HAART) (concordant). In comparison to concordant patients, discordant patients showed poor lymphocyte proliferation, lower secretion of IL-2 and IFN-gamma, a lower percentage of perforin and granzyme-B-producing CD8 T cells, and poor differentiation of effector memory CD8 T(EM) cells into CD8 T(EMRA) cells in in-vitro stimulation assays, especially against HIV-1 Gag p24 and one of its peptide pools. Functional CD8 T-cell responses of discordant patients after stimulation with recall antigens, Candida albicans, and tetanus toxoid, were also inferior to concordant patients, but comparable to normal healthy controls. Examination of the multifunctional roles of T cells is imperative in describing the overall magnitude of immune responses to HIV-1. Our results suggest that prolonged suppression of plasma viremia alone does not warrant good qualitative and quantitative CD8 T-cell responses to HIV-1, implying that CD4 T cells are required for maintenance of protective CD8 T-cell responses.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Infecções por HIV/imunologia , HIV-1/imunologia , Carga Viral , Viremia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Adulto , Idoso , Animais , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/imunologia , Candida albicans/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Toxoide Tetânico/imunologia , Adulto Jovem
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