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1.
Adv Protein Chem Struct Biol ; 140: 37-57, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38762275

RESUMO

For decades, antibodies have remained the archetypal binding proteins that can be rapidly produced with high affinity and specificity against virtually any target. A conventional antibody is still considered the prototype of a binding molecule. It is therefore not surprising that antibodies are routinely used in basic scientific and biomedical research, analytical workflows, molecular diagnostics etc. and represent the fastest growing sector in the field of biotechnology. However, several limitations associated with conventional antibodies, including stringent requirement of animal immunizations, mammalian cells for expression, issues on stability and aggregation, bulkier size and the overall time and cost of production has propelled evolution of concepts along alternative antigen binders. Rapidly evolving protein engineering approaches and high throughput screening platforms have further complemented the development of myriads of classes of non-conventional protein binders including antibody derived as well as non-antibody based molecular scaffolds. These non-canonical binders are finding use across disciplines of which diagnostics and therapeutics are the most noteworthy.


Assuntos
Anticorpos , Antígenos , Engenharia de Proteínas , Humanos , Antígenos/imunologia , Antígenos/química , Animais , Anticorpos/imunologia , Anticorpos/química
2.
Adv Protein Chem Struct Biol ; 140: 249-292, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38762271

RESUMO

Cancer is no longer recognized as a single disease but a collection of diseases each with its defining characteristics and behavior. Even within the same cancer type, there can be substantial heterogeneity at the molecular level. Cancer cells often accumulate various genetic mutations and epigenetic alterations over time, leading to a coexistence of distinct subpopulations of cells within the tumor. This tumor heterogeneity arises not only due to clonal outgrowth of cells with genetic mutations, but also due to interactions of tumor cells with the tumor microenvironment (TME). The latter is a dynamic ecosystem that includes cancer cells, immune cells, fibroblasts, endothelial cells, stromal cells, blood vessels, and extracellular matrix components, tumor-associated macrophages and secreted molecules. The complex interplay between tumor heterogeneity and the TME makes it difficult to develop one-size-fits-all treatments and is often the cause of therapeutic failure and resistance in solid cancers. Technological advances in the post-genomic era have given us cues regarding spatial and temporal tumor heterogeneity. Armed with this knowledge, oncologists are trying to target the unique genomic, epigenetic, and molecular landscape in the tumor cell that causes its oncogenic transformation in a particular patient. This has ushered in the era of personalized precision medicine (PPM). Immunotherapy, on the other hand, involves leveraging the body's immune system to recognize and attack cancer cells and spare healthy cells from the damage induced by radiation and chemotherapy. Combining PPM and immunotherapy represents a paradigm shift in cancer treatment and has emerged as a promising treatment modality for several solid cancers. In this chapter, we summarise major types of cancer immunotherapy and discuss how they are being used for precision medicine in different solid tumors.


Assuntos
Imunoterapia , Neoplasias , Medicina de Precisão , Microambiente Tumoral , Humanos , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/genética , Microambiente Tumoral/imunologia
3.
Adv Protein Chem Struct Biol ; 139: 89-139, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38448145

RESUMO

The word 'cancer' encompasses a heterogenous group of distinct disease types characterized by a spectrum of pathological features, genetic alterations and response to therapies. According to the World Health Organization, cancer is the second leading cause of death worldwide, responsible for one in six deaths and hence imposes a significant burden on global healthcare systems. High-throughput omics technologies combined with advanced imaging tools, have revolutionized our ability to interrogate the molecular landscape of tumors and has provided unprecedented understanding of the disease. Yet, there is a gap between basic research discoveries and their translation into clinically meaningful therapies for improving patient care. To bridge this gap, there is a need to analyse the vast amounts of high dimensional datasets from multi-omics platforms. The integration of multi-omics data with clinical information like patient history, histological examination and imaging has led to the novel concept of clinicomics and may expedite the bench-to-bedside transition in cancer. The journey from omics to clinicomics has gained momentum with development of radiomics which involves extracting quantitative features from medical imaging data with the help of deep learning and artificial intelligence (AI) tools. These features capture detailed information about the tumor's shape, texture, intensity, and spatial distribution. Together, the related fields of multiomics, translational bioinformatics, radiomics and clinicomics may provide evidence-based recommendations tailored to the individual cancer patient's molecular profile and clinical characteristics. In this chapter, we summarize multiomics studies in solid cancers with a specific focus on breast cancer. We also review machine learning and AI based algorithms and their use in cancer diagnosis, subtyping, prognosis and predicting treatment resistance and relapse.


Assuntos
Inteligência Artificial , Neoplasias da Mama , Humanos , Feminino , Algoritmos , Biologia Computacional , Aprendizado de Máquina
4.
Exp Eye Res ; 238: 109720, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37952723

RESUMO

Interleukin (IL) 1B is an important candidate gene in glaucoma pathogenesis as it affects the survival of retinal ganglion cells (RGCs). In the present study, -511T/C and +3953C/T polymorphisms in the IL1B were assessed as genetic risk factors for primary open angle (POAG) and angle closure glaucoma (PACG) in a North Indian Punjabi cohort comprising 867 samples (POAG cases = 307; PACG cases = 133 and controls = 427). Genetic association, diplotype and linkage disequilibrium (LD) analyses were performed. Corrections for confounding variables and multiple testing were applied. An updated meta-analysis was also performed. Pooled OR with 95% CI was calculated for dominant, over dominant, and recessive models. Level of heterozygosity among studies was tested using I2 statistic with fixed or random effect model based on the extent of heterogeneity. For -511T > C polymorphism, a positive association was observed with PACG under dominant (p = 0.038; OR = 0.65; pcorr = 0.011; OR = 0.55) and over dominant models (p = 0.010; OR = 0.59; pcorr = 0.001; OR = 0.46). Significant association of +3953C > T was also observed with POAG under dominant (p = 0.011; OR = 1.46; pcorr = 0.018; OR = 1.48) and PACG under recessive models (p < 0.0001; OR = 4.47; pcorr<0.0001; OR = 4.06). While C-C diplotype provided protection against primary glaucoma (0.67-fold; p = 0.0004), T-T and T-C diplotypes predisposed individuals to higher risk (1.31-fold; p = 0.030 and 1.36-fold; p = 0.022 respectively). In meta-analysis, a significant association between +3453 C>T and POAG was observed under dominant (pooled OR = 1.33, p = 0.0046) and over dominant (pooled OR = 1.25; p = 0.0269) models with overall heterogeneity of 15% and 0% respectively. The study provides strong evidence of IL1B variants in modifying genetic susceptibility to primary glaucoma in the targeted North Indian Punjabi population. Replication of the present findings in other populations, and functional studies are warranted to further assess the relevance of IL1B variants in the pathogenesis of primary glaucoma.


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma de Ângulo Aberto , Glaucoma , Humanos , Glaucoma de Ângulo Aberto/genética , Polimorfismo de Nucleotídeo Único , Glaucoma/genética , Predisposição Genética para Doença , Glaucoma de Ângulo Fechado/genética , Interleucina-1beta/genética
5.
Heliyon ; 9(12): e22121, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38196838

RESUMO

Visceral Leishmaniasis (VL) is a neglected tropical disease of public health importance in the Indian subcontinent. Despite consistent elimination initiatives, the disease has not yet been eliminated and there is an increased risk of resurgence from active VL reservoirs including asymptomatic, post kala azar dermatitis leishmaniasis (PKDL) and HIV-VL co-infected individuals. To achieve complete elimination and sustain it in the long term, a prophylactic vaccine, which can elicit long lasting immunity, is desirable. In this study, we employed immunoinformatic tools to design a multi-subunit epitope vaccine for the Indian population by targeting antigenic secretory proteins screened from the Leishmania donovani proteome. Out of 8014 proteins, 277 secretory proteins were screened for their cellular location and proteomic evidence. Through NCBI BlastP, unique fragments of the proteins were cropped, and their antigenicity was evaluated. B-cell, HTL and CTL epitopes as well as IFN-ɣ, IL-17, and IL-10 inducers were predicted, manually mapped to the fragments and common regions were tabulated forming a peptide ensemble. The ensemble was evaluated for Class I MHC immunogenicity and toxicity. Further, immunogenic peptides were randomly selected and used to design vaccine constructs. Eight vaccine constructs were generated by linking random peptides with GS linkers. Synthetic TLR-4 agonist, RS09 was used as an adjuvant and linked with the constructs using EAAK linkers. The predicted population coverage of the constructs was ∼99.8 % in the Indian as well as South Asian populations. The most antigenic, nontoxic, non-allergic construct was chosen for the prediction of secondary and tertiary structures. The 3D structures were refined and analyzed using Ramachandran plot and Z-scores. The construct was docked with TLR-4 receptor. Molecular dynamic simulation was performed to check for the stability of the docked complex. Comparative in silico immune simulation studies showed that the predicted construct elicited humoral and cell-mediated immunity in human host comparable to that elicited by Leish-F3, which is a promising vaccine candidate for human VL.

6.
Transl Oncol ; 21: 101426, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35460943

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common non-skin cancer with a tobacco consumption and infection with high-risk human papillomavirus (HPV) being major risk factors. Despite advances in numerous therapy modalities, survival rates for HNSCC have not improved considerably; a vast number of clinical outcomes have demonstrated that a combination strategy (the most well-known docetaxel, cisplatin, and 5-fluorouracil) is the most effective treatment choice. Immunotherapy that targets immunological checkpoints is being tested in a number of clinical trials, either alone or in conjunction with chemotherapeutic or targeted therapeutic drugs. Various monoclonal antibodies, such as cetuximab and bevacizumab, which target the EGFR and VEGFR, respectively, as well as other signaling pathway inhibitors, such as temsirolimus and rapamycin, are also being studied for the treatment of HNSCC. We have reviewed the primary targets in active clinical studies in this study, with a particular focus on the medications and drug targets used.

7.
IEEE Trans Biomed Circuits Syst ; 16(1): 36-51, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34962876

RESUMO

An adaptive PPG (Photoplethysmography) readout system for a dual-channel OLED-OPD flexible sensor is designed and developed with motion artifact (<1Hz) and ambient lighting interference successfully compensated without any additional motion sensors. The compensation is made possible by adopting multi-feedbacks and an additional reference OPD channel to cancel effectively DC drifts. In result, the quality of measured PPG is improved to the level such that long-time, continuous quality monitoring of bio-sign such as heart rate (HR) is possible. The readout is designed with an auto-programmable band-pass trans-impedance amplifier (TIA) of a 100dbΩ gain with a continuous-type DC-current cancellation loop. The rest of the readout consists of a 0.5 Hz low-pass filter, an additional second-order band-pass filter (0.1-10Hz), a difference amplifier, a motion reference channel, an analog multiplexer, a programmable gain amplifier (PGA), a digital control and a programmable DAC-PWM based auto-intensity tuned OLED driver. The readout is fabricated in an area of 9 mm2 via the TSMC 180nm process. The experiment result shows that the developed OLED-OPD readout senses well as small as 1nA current, with a measured dynamic range >90dB (1nA to 100 µA) and input-referred noise of 0.26 nA/√H, with power consumption of 460µW. The DC drift is successfully reduced to 1% of its average. The accuracy for heart rate is 96%.


Assuntos
Amplificadores Eletrônicos , Fotopletismografia , Desenho de Equipamento , Movimento (Física) , Semicondutores , Processamento de Sinais Assistido por Computador
8.
J Invest Dermatol ; 142(6): 1725-1736.e10, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34808236

RESUMO

Severe angiopathy is a major driver for diabetes-associated secondary complications. Knowledge on the underlying mechanisms essential for advanced therapies to attenuate these pathologies is limited. Injection of ABCB5+ stromal precursors at the edge of nonhealing diabetic wounds in a murine db/db model, closely mirroring human type 2 diabetes, profoundly accelerates wound closure. Strikingly, enhanced angiogenesis was substantially enforced by the release of the ribonuclease angiogenin from ABCB5+ stromal precursors. This compensates for the profoundly reduced angiogenin expression in nontreated murine chronic diabetic wounds. Silencing of angiogenin in ABCB5+ stromal precursors before injection significantly reduced angiogenesis and delayed wound closure in diabetic db/db mice, implying an unprecedented key role for angiogenin in tissue regeneration in diabetes. These data hold significant promise for further refining stromal precursors-based therapies of nonhealing diabetic foot ulcers and other pathologies with impaired angiogenesis.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Pé Diabético/patologia , Pé Diabético/terapia , Camundongos , Camundongos Endogâmicos , Neovascularização Patológica/patologia , Ribonuclease Pancreático , Cicatrização
9.
Mol Biol Rep ; 48(8): 6197-6203, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34318437

RESUMO

BACKGROUND: Hypoxic injury to retinal ganglionic cells and adjoining glia is implicated in glaucomatous optic neuropathy. The present study evaluates the effect of IL-6 on R28 retinal precursor cell line exposed to hypoxic injury. METHODS AND RESULTS: Apoptotic cell death induced by hypoxia mimetic CoCl2 in R28 cells with or without IL-6 treatment was measured using cell viability assays and apoptotic markers. Oxidative stress was also measured. Hypoxia induced by mimetic CoCl2 led to a time and concentration dependent apoptosis of cells mediated by disruption of mitochondrial membrane potential and activation of caspase 3. Cells pre-treated with IL-6 demonstrated significantly higher viability and mitochondrial integrity under hypoxic conditions. A critical role of STAT3 was observed in mediating the cytoprotective effects of IL-6. Treatment of cells with IL-6 led to STAT3-mediated expression of the Bcl-2 family proteins and MnSOD. CONCLUSIONS: The data from the present study indicate cytoprotective role of IL-6 and suggest a previously unreported mechanism of neuroprotection via STAT3 mediated signaling.


Assuntos
Hipóxia Celular/fisiologia , Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cobalto/efeitos adversos , Cobalto/farmacologia , Hipóxia/fisiopatologia , Interleucina-6/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Retina/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
BMC Ophthalmol ; 21(1): 165, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832461

RESUMO

PURPOSE: Transforming growth factor beta (TGFB) is an important candidate gene implicated in glaucoma pathogenesis because it affects retinal ganglionic cell survival. The present study assessed the genetic association of -509C > T variant in the TGFB promoter region with primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) in a North Indian Punjabi population. METHOD: A total of 867 subjects (307 POAG, 133 PACG cases and 427 controls) were recruited from the targeted population. Genotyping was done by PCR-RFLP method and the data was analyzed using PLINK software (v1.07). Logistic regression under different genetic models was applied and genotype phenotype correlation was assessed by one-way ANOVA. RESULT: A statistically significant difference in the frequency of heterozygotes among PACG cases (53.16%) and controls (30.07%) (p = 0.0002) was observed. Genetic model analysis revealed that mutant "TT" genotype conferred 2-fold risk towards PACG development under recessive model (p = 0.0019) while dominant model and co-dominant model provided 0.62 and 0.37 fold protection against PACG (p = 0.025 and p = 0.0001, respectively). Data segregation based on sex revealed a strong protective effect of heterozygous 'CT' genotype against progression of PACG among females (p = 0.002, OR = 0.37, 95% CI = 0.19-0.70), but conferred 2.14-fold risk among female POAG subjects (p = 0.013). CONCLUSION: The study revealed a strong genetic association of -509C > T variant in TGFB with PACG in females. There is a need to replicate the results in a larger PACG cohort in other populations and further assess the contribution of sex specific factors in modifying genetic susceptibility to PACG.


Assuntos
Glaucoma de Ângulo Fechado/genética , Fator de Crescimento Transformador beta1/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
11.
Microsyst Technol ; 27(6): 2315-2343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33281302

RESUMO

This study presents an external temperature sensor assisted a new low power, time-interleave, wide dynamic range, and low DC drift photoplethysmography (PPG) signal acquisition system to obtain the accurate measurement of various bio signs in real-time. The designed chip incorporates a 2-bit control programmable transimpedance amplifier (TIA), a high order filter, a 3:8 programmable gain amplifier (PGA) and 2 × 2 organic light-emitting diode (OLED) driver. Temperature sensor is used herein to compensate the adverse effect of low-skin-temperature on the PPG signal quality. The analog front-end circuit is implemented in the integrated chip with chip area of 2008 µm × 1377 µm and fabricated via TSMC T18 process. With the standard 1.8 V, the experimental result shows that the measured current sensing range is 20 nA-100 uA. The measured dynamic range of the designed readout circuit is 80 dB. The estimated signal to noise ratio is 60 dB@1 uA, and the measured input referred noise is 60.2 pA/Hz½. The total power consumption of the designed chip is 31.32 µW (readout) + 1.62 mW (OLED driver@100% duty cycle). The non-invasive PPG sensor is applied to the wrist artery of the 40 healthy subjects for sensing the pulsation of the blood vessel. The experimental results show that for every 1 °C decrease in mean ambient temperature tends to 0.06 beats/min, 0.125 mmHg and 0.063 mmHg increase in hear rate (HR), systolic (SBP) and diastolic (DBP), respectively. Similarly, for every 1 °C increase in mean ambient temperature tends to 0.13 beats/min, 0.601 mmHg and 0.121 mmHg increase in HR, SBP and DBP, respectively. The measured accuracy and standard error for the HR estimation are 96%, and - 0.022 ± 2.589 beats/minute, respectively. The oxygen stauration (SpO2) measurement results shows that the mean absolute percentage error is less than 5%. The resultant errors for the SBP and DBP measurement are - 0.318 ± 5.19 mmHg and - 0.5 ± 1.91 mmHg, respectively.

12.
Front Cell Infect Microbiol ; 10: 614165, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33680983

RESUMO

Nitric oxide (NO) is an anti-microbial effector of the innate immune system which plays major role in non-specific killing of various pathogens including protozoan parasites. However, due to subversion of the host's immune processes by pathogens, suboptimal production of NO is frequently found in many infection models. Previous studies have shown suppressed NO production during Leishmania donovani infection, the causative agent of visceral leishmaniasis (VL). Availability of L-Arginine, a semi-essential amino acid is required for inducible nitric oxide synthase (iNOS) mediated NO production. However, arginase is another enzyme, which if expressed concomitantly, may strongly compete for L-Arginine, and suppress NO production by iNOS. In the present study, plasma nitrite and arginase levels were measured in VL patients before and after successful drug treatment, endemic and non-endemic healthy donors. We observed significantly lower NO levels in the plasma of VL patients as compared to endemic controls, which improved significantly post-treatment. Significantly elevated arginase activity was also observed in the plasma of VL patients, which may be associated with NO deficiency. VL patients also showed significantly higher levels of IL-10 and TGF-ß, which are known to regulate expression of arginase in various immune cells. In vitro studies with human peripheral blood mononuclear cells (PBMCs) further corroborated the role of IL-10 and TGF-ß in arginase mediated suppression of NO production.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Arginase/metabolismo , Citocinas/metabolismo , Humanos , Interleucina-10 , Leucócitos Mononucleares/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Crescimento Transformador beta
13.
Nat Commun ; 9(1): 3425, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30143626

RESUMO

Transcription factors ensure skin homeostasis via tight regulation of distinct resident stem cells. Here we report that JunB, a member of the AP-1 transcription factor family, regulates epidermal stem cells and sebaceous glands through balancing proliferation and differentiation of progenitors and by suppressing lineage infidelity. JunB deficiency in basal progenitors results in a dermatitis-like syndrome resembling seborrheic dermatitis harboring structurally and functionally impaired sebaceous glands with a globally altered lipid profile. A fate switch occurs in a subset of JunB deficient epidermal progenitors during wound healing resulting in de novo formation of sebaceous glands. Dysregulated Notch signaling is identified to be causal for this phenotype. In fact, pharmacological inhibition of Notch signaling can efficiently restore the lineage drift, impaired epidermal differentiation and disrupted barrier function in JunB conditional knockout mice. These findings define an unprecedented role for JunB in epidermal-pilosebaceous stem cell homeostasis and its pathology.


Assuntos
Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular/fisiologia , Epiderme/metabolismo , Camundongos , Camundongos Knockout , Glândulas Sebáceas/citologia , Glândulas Sebáceas/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Cicatrização/genética , Cicatrização/fisiologia
14.
PLoS One ; 13(2): e0192636, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29432439

RESUMO

MMP (Matrix metalloproteinase) 9 is reported to affect glaucoma pathogenesis by altering intraocular pressure (IOP) through its role in remodeling the extracellular matrix (ECM) in the trabecular meshwork. A genetic variant at the promoter region in the MMP9 gene (-1562C>T) has a putative role in regulating its transcription rate and hence can affect genetic predisposition to primary glaucoma. The present study examined the association of -1562C>T promoter polymorphism in the MMP9 gene with Primary Open Angle Glaucoma (POAG) and Primary Angle Closure Glaucoma (PACG) in a north Indian population. A total of 729 subjects (POAG = 224, PACG = 138 and 367 controls) were recruited for the study. Genotyping for the promoter sequence variant was done with PCR-RFLP method. Genotypic and allelic frequency distribution of the POAG and PACG data sets were compared to that of controls by chi-square test and genetic association was tested under different genetic models as implemented under PLINK. Statistically significant difference was observed in the genotype frequencies between PACG cases and controls (p = 0.030). However, in the POAG cases, this difference was only borderline (p = 0.052). Genetic model analysis, under the dominant model revealed 1.6 and 1.4 fold increased susceptibility to PACG and POAG (p = 0.012, p = 0.032) respectively. A higher frequency of CT genotype was observed in PACG as well as POAG males as compared to female subjects. According to the dominant model, CT+TT genotype conferred 1.8 fold higher risk of developing PACG among male patients as compared to the control group (p = 0.048, OR = 1.87;1.00-3.50). Current findings suggest significant association of MMP9 -1562C>T polymorphism with primary glaucoma in the targeted north Indian population and warrant further replication of the findings in other populations.


Assuntos
Predisposição Genética para Doença , Glaucoma/genética , Metaloproteinase 9 da Matriz/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Índia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
15.
Front Immunol ; 7: 456, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27826299

RESUMO

Members of the Bcl-2 family are major regulators of apoptosis in mammalian cells, and hence infection-induced perturbations in their expression could result into elimination of the parasites or creation of a niche favoring survival. In this investigation, we uncover a novel role of host Bcl-2 in sustaining Leishmania donovani infection. A rapid twofold increase in Bcl-2 expression occurred in response to parasite challenge. Downregulation of post infection Bcl-2 increase using siRNA or functional inhibition using Bcl-2 small molecule inhibitors interfered with intracellular parasite survival confirming the necessity of elevated Bcl-2 during infection. An increased nitric oxide (NO) response and reduced parasitic burden was observed upon Bcl-2 inhibition, where restitution of the NO response accounted for parasite mortality. Mechanistic insights revealed a major role of elevated Th2 cytokine IL-13 in parasite-induced Bcl-2 expression via the transcription factor STAT-3, where blocking at the level of IL-13 receptor or downstream kinase JAK-2 dampened Bcl-2 induction. Increase in Bcl-2 was orchestrated through Toll like receptor (TLR)-2-MEK-ERK signaling, and changes in TLR-2 levels affected parasite uptake. In a mouse model of visceral leishmaniasis (VL), Bcl-2 inhibitors partially restored the antimicrobial NO response by at least a twofold increase that resulted in significantly reduced parasite burden. Interestingly, monocytes derived from the peripheral blood of six out of nine human VL subjects demonstrated Bcl-2 expression at significantly higher levels, and sera from these patients showed only marginally quantifiable nitrites. Collectively, our study for the first time reveals a pro-parasitic role of host Bcl-2 and the capacity of host-derived IL-13 to modulate NO levels during infection via Bcl-2. Here, we propose Bcl-2 inhibition as a possible therapeutic intervention for VL.

16.
Autophagy ; 12(10): 1817-1831, 2016 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-27459332

RESUMO

Leishmania is an obligate intracellular parasite that replicates inside phagolysosomes or parasitophorous vacuoles (PV) of the monocyte/macrophage lineage. It reprograms macrophages and produces a metabolic state conducive to successful infection and multiplication. MicroRNAs (miRNAs), a class of small 22 to 24 nucleotide noncoding regulatory RNAs alter the gene expression and consequently proteome output by targeting mRNAs, may play a regulatory role in modulating host cell functions. In the present study, we demonstrate the novel regulatory role of host microRNA, MIR30A-3p in modulation of host cell macroautophagy/autophagy after infection with L. donovani. Our in vitro studies showed that MIR30A-3p expression was significantly enhanced after L. donovani infection in a time-dependent manner. Transient transfection with a MIR30A-3p inhibitor followed by L. donovani infection promoted the autophagic response and decreased the intracellular parasite burden in both THP-1 cells and human monocyte-derived macrophages (HsMDM). BECN1/Beclin 1, the mammalian ortholog of yeast Vps30/Atg6, is a key autophagy-promoting protein that plays a key role in the regulation of cell death and survival. We report BECN1-dependent modulation of host cell autophagy in response to L. donovani infection. Pretreatment of L. donovani-infected macrophages with the MIR30A-3p mimic decreased and with antagomir increased the expression of BECN1 protein. We demonstrate that BECN1 is a potential target of MIR30A-3p and this miRNA negatively regulates BECN1 expression. Our present study reveals for the first time a novel role of MIR30A-3p in regulating autophagy-mediated L. donovani elimination by targeting BECN1. The present study has significant impact for the treatment of visceral leishmaniasis.


Assuntos
Autofagia/genética , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Leishmania donovani/fisiologia , Leishmaniose Visceral/genética , Leishmaniose Visceral/parasitologia , MicroRNAs/genética , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Proteína Beclina-1/metabolismo , Linhagem Celular , Análise por Conglomerados , Regulação da Expressão Gênica , Humanos , Leishmaniose Visceral/patologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Macrófagos/patologia , MicroRNAs/metabolismo , Monócitos/patologia , Parasitos/fisiologia , Enzimas de Conjugação de Ubiquitina/metabolismo , Regulação para Cima/genética
17.
Psychiatry Res ; 229(3): 933-9, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26205629

RESUMO

Suicide as a public health problem is studied worldwide and association of psychiatric and genetic risk factors for suicidal behavior are the point of discussion in studies across different ethnic groups. The present study is aimed at evaluating psychiatric and genetic traits among primary relatives of suicide completer families in an urban Indian population. Bi-variate analysis shows significant increase in major depression (PHQ and Hamilton), stress, panic disorder, somatoform disorder and suicide attemptamong primary compared to other relatives. Sib pair correlations also reveal significant results for major depression (Hamilton), stress, suicide attempt, intensity of suicide ideation and other anxiety syndrome. 5-HTTLPR, 5-HTT (Stin2) and COMT risk alleles are higher among primary relatives, though statistically insignificant. Backward conditional logistic regression analysis show only independent variable, Depression (Hamilton) made a unique statistically significant contribution to the model in primary relatives.


Assuntos
Família/psicologia , Predisposição Genética para Doença/psicologia , Transtornos Mentais/genética , Suicídio/psicologia , População Branca/psicologia , Adulto , Ansiedade/genética , Ansiedade/psicologia , Depressão/genética , Depressão/psicologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Índia/etnologia , Masculino , Transtornos Mentais/psicologia , Fatores de Risco , Transtornos Somatoformes/genética , Transtornos Somatoformes/psicologia , População Urbana , População Branca/genética
18.
Infect Immun ; 83(5): 1853-68, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25690103

RESUMO

Leishmania donovani, a protozoan parasite, is the causative agent of visceral leishmaniasis. It lives and multiplies within the harsh environment of macrophages. In order to investigate how intracellular parasite manipulate the host cell environment, we undertook a quantitative proteomic study of human monocyte-derived macrophages (THP-1) following infection with L. donovani. We used the isobaric tags for relative and absolute quantification (iTRAQ) method and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to compare expression profiles of noninfected and L. donovani-infected THP-1 cells. We detected modifications of protein expression in key metabolic pathways, including glycolysis and fatty acid oxidation, suggesting a global reprogramming of cell metabolism by the parasite. An increased abundance of proteins involved in gene transcription, RNA splicing (heterogeneous nuclear ribonucleoproteins [hnRNPs]), histones, and DNA repair and replication was observed at 24 h postinfection. Proteins involved in cell survival and signal transduction were more abundant at 24 h postinfection. Several of the differentially expressed proteins had not been previously implicated in response to the parasite, while the others support the previously identified proteins. Selected proteomics results were validated by real-time PCR and immunoblot analyses. Similar changes were observed in L. donovani-infected human monocyte-derived primary macrophages. The effect of RNA interference (RNAi)-mediated gene knockdown of proteins validated the relevance of the host quantitative proteomic screen. Our findings indicate that the host cell proteome is modulated after L. donovani infection, provide evidence for global reprogramming of cell metabolism, and demonstrate the complex relations between the host and parasite at the molecular level.


Assuntos
Leishmania donovani/imunologia , Macrófagos/química , Macrófagos/parasitologia , Proteoma/análise , Linhagem Celular , Cromatografia Líquida , Perfilação da Expressão Gênica , Humanos , Immunoblotting , Macrófagos/imunologia , Proteômica , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem
19.
Indian J Hum Genet ; 20(2): 155-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25400344

RESUMO

BACKGROUND: 677C to T allele in the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene has been implicated in the etiology of various syndromes and nonsyndromic diseases but till date no direct studies have been reported with craniosynostosis. OBJECTIVES: The aim was to study the family-based association of MTHFR polymorphism in different categories of craniosynostosis patients. MATERIALS AND METHODS: This was a cross-sectional study in which 30 patients classified as Apert syndrome, Pfeiffr syndrome and nonsyndromic craniosynostosis patients with their family were recruited. A sample of 3 ml intravenous blood was taken from patients and from their family members (father and mother) in ethylenediaminetetraacetic acid-anticoagulated vacutainer for the purpose of the study. Genomic DNA was extracted from peripheral blood lymphocytes by phenol chloroform extraction method. Primers for MTHFR gene were designed. The polymerase chain reaction was carried out. After successful amplification, a small aliquot (5 µl) of the MTHFR reaction mixture was treated with 1 units of Hinf I restriction enzyme (NEB). Results were obtained and compiled. RESULTS: A total of 30 patients/participants with craniosynostosis of Indian descent and their parents formed the study group. The genotyping did not confirm an association between the MTHFR 677C to T polymorphism and between different categories of craniosynostosis. When comparing the offspring of mothers statistically significant differences were found. CONCLUSION: C667T polymorphism of the MTHFR gene is unlikely to play a role in the pathogenesis of craniosynostosis though maternal MTHFR C677T polymorphism may be a genetic risk factor.

20.
Indian J Hum Genet ; 19(4): 449-53, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24497711

RESUMO

OBJECTIVE: The Objective of this study was to identify the association of mutation of fibroblast growth factor receptor 1 (FGFR1), FGFR2 genes with syndromic as well as non-syndromic craniosynostosis in Indian population. MATERIALS AND METHODS: Retrospective analysis of our records from January 2008 to December 2012 was done. A total of 41 cases satisfying the inclusion criteria and 51 controls were taken for the study. A total volume of 3 ml blood from the patient as well as parents was taken. Deoxyribonucleic acid extracted using phenol chloroform extraction method followed by polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: There were 33 (80.4%) non-syndromic cases of craniosynostosis while 8 (19.5%) were syndromic. Out of these 8 syndromic cases, 4 were Apert syndrome, 3 were Crouzon syndrome and 1 Pfeiffer syndrome. Phenotypically the most common non-syndromic craniosynostosis was scaphocephaly (19, 57.7%) followed by plagiocephaly in (14, 42.3%). FGFR1 mutation (Pro252Arg) was seen in 1 (2.4%) case of non-syndromic craniosynostosis while no association was noted either with FGFR1 or with FGFR2 mutation in syndromic cases. None of the control group showed any mutation. CONCLUSION: Our study proposed that FGFR1, FGFR2 mutation, which confers predisposition to craniosynostosis does not exist in Indian population when compared to the western world.

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