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1.
Pharmaceutics ; 16(3)2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38543301

ABSTRACT

The continuous evolution of new viruses poses a danger to world health. Rampant outbreaks may advance to pandemic level, often straining financial and medical resources to breaking point. While vaccination remains the gold standard to prevent viral illnesses, these are mostly prophylactic and offer minimal assistance to those who have already developed viral illnesses. Moreover, the timeline to vaccine development and testing can be extensive, leading to a lapse in controlling the spread of viral infection during pandemics. Antiviral therapeutics can provide a temporary fix to tide over the time lag when vaccines are not available during the commencement of a disease outburst. At times, these medications can have negative side effects that outweigh the benefits, and they are not always effective against newly emerging virus strains. Several limitations with conventional antiviral therapies may be addressed by nanotechnology. By using nano delivery vehicles, for instance, the pharmacokinetic profile of antiviral medications can be significantly improved while decreasing systemic toxicity. The virucidal or virus-neutralizing qualities of other special nanomaterials can be exploited. This review focuses on the recent advancements in nanomedicine against RNA viruses, including nano-vaccines and nano-herbal therapeutics.

2.
Hum Immunol ; 84(12): 110724, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37932183

ABSTRACT

Cervical cancer is the second-most prevalent gynecologic cancer in India. It is typically detected in women between the ages of 35 and 44. Cervical cancer is mainly associated with the human papillomavirus (HPV). The report shows that 70 % of cervical cancer is caused by HPV 16 and 18. There are few therapeutic options and vaccines available for cervical cancer treatment and γδ T cell therapy is one of them. This therapy can kill various types of cancers, including cervical cancer. The major γδ T cell subset is the Vγ9Vδ2 T cell, mainly distributed in peripheral blood which recognize non-MHC peptide antigens and can eliminate MHC-downregulated cancer. Moreover, γδ T cells can express different types of receptors that bind to the molecules of stressed cells, often produced on cancerous cells but absent from healthy tissue. γδ T cells possess both direct and indirect cytotoxic capabilities against malignancies and show potential antitumoral responses. However, γδ T cells also encourage the progression of cancer. Cancer immunotherapy using γδ T cells will be a potential cancer treatment, as well as cervical cancer. This review focused on the γδ T cell and its function in cancer, with special emphasis on cervical cancer. It also focused on the ligand recognition site of γδ T cells, galectin-mediated therapy and pamidronate-treated therapy for cervical cancer. Instead of the great potential of γδ T cell for the eradication of cervical cancer, no comprehensive in-depth review is available to date, so there is a need to jot down the various roles and modes of action and different applications of γδ T cells for cancer research, which we believe will be a handy tool for the researchers and the readers.


Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Adult , Uterine Cervical Neoplasms/therapy , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Immunotherapy , Pamidronate , India
3.
Front Microbiol ; 14: 1196838, 2023.
Article in English | MEDLINE | ID: mdl-37180224
4.
Biosensors (Basel) ; 13(3)2023 Mar 06.
Article in English | MEDLINE | ID: mdl-36979561

ABSTRACT

Every year, the dengue virus and its principal mosquito vector, Aedes sp., have caused massive outbreaks, primarily in equatorial countries. The pre-existing techniques available for dengue detection are expensive and require trained personnel. Graphene and its derivatives have remarkable properties of electrical and thermal conductivity, and are flexible, light, and biocompatible, making them ideal platforms for biosensor development. The incorporation of these materials, along with appropriate nanomaterials, improves the quality of detection methods. Graphene can help overcome the difficulties associated with conventional techniques. In this review, we have given comprehensive details on current graphene-based diagnostics for dengue virus detection. We have also discussed state-of-the-art biosensing technologies and evaluated the advantages and disadvantages of the same.


Subject(s)
Biosensing Techniques , Dengue Virus , Graphite , Nanostructures , Animals , Biosensing Techniques/methods
5.
Heliyon ; 8(12): e12207, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36578430

ABSTRACT

A rapid surge in world population leads to an increase in worldwide demand for agricultural products. Nanotechnology and its applications in agriculture have appeared as a boon to civilization with enormous potential in transforming conventional farming practices into redefined farming activities. Low-cost portable nanobiosensors are the most effective diagnostic tool for the rapid on-site assessment of plant and soil health including plant biotic and abiotic stress level, nutritional status, presence of hazardous chemicals in soil, etc. to maintain proper farming and crop productivity. Nanobiosensors detect physiological signals and convert them into standardized detectable signals. In order to achieve a reliable sensing analysis, nanoparticles can aid in signal amplification and sensor sensitivity by lowering the detection limit. The high selectivity and sensitivity of nanobiosensors enable early detection and management of targeted abnormalities. This study identifies the types of nanobiosensors according to the target application in agriculture sector.

6.
Sci Rep ; 12(1): 15493, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-36109567

ABSTRACT

The main effectors in the innate immune system of Bombyx mori L. are antimicrobial peptides (AMPs). Here, we infected B. mori with varied inoculum sizes of Pseudomonas aeruginosa ATCC 25668 cells to investigate changes in morpho-anatomical responses, physiological processes and AMP production. Ultraviolet-visible spectra revealed a sharp change in λmax from 278 to 285 nm (bathochromic shift) in the hemolymph of infected B. mori incubated for 24 h. Further, Fourier Transform InfraRed studies on the hemolymph extracted from the infected B. mori showed a peak at 1550 cm-1, indicating the presence of α-helical peptides. The peptide fraction was obtained through methanol, acetic acid and water mixture (90:1:9) extraction, followed by peptide purification using Reverse Phase High Performance Liquid Chromatography. The fraction exhibiting antibacterial properties was collected and characterized by Matrix-Assisted Laser Desorption/Ionization-Time of Flight. A linear α-helical peptide with flexible termini (LLKELWTKMKGAGKAVLGKIKGLL) was found, corresponding to a previously described peptide from ant venom and here denominated as Bm-ponericin-L1. The antibacterial activity of Bm-ponericin-L1 was determined against ESKAPE pathogens. Scanning electron microscopy confirmed the membrane disruption potential of Bm-ponericin-L1. Moreover, this peptide also showed promising antibiofilm activity. Finally, cell viability and hemolytic assays revealed that Bm-ponericin-L1 is non-toxic toward primary fibroblasts cell lines and red blood cells, respectively. This study opens up new perspectives toward an alternative approach to overcoming multiple-antibiotic-resistance by means of AMPs through invertebrates' infection with human pathogenic bacteria.


Subject(s)
Ant Venoms , Anti-Infective Agents , Bombyx , Pseudomonas Infections , Animals , Humans , Anti-Bacterial Agents/pharmacology , Hemolymph , Methanol , Peptides/chemistry , Pseudomonas Infections/drug therapy , Water
7.
Cancer Invest ; 40(8): 700-709, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35333689

ABSTRACT

Pancreatic Ductal Adenocarcinoma (PDAC) has a poor patient survival rate in comparison with other cancer types, even after targeted therapy, chemotherapy, and immunotherapy. Therefore, a great deal needs to be done to gain a better understanding of the biology and identification of prognostic and predictive markers for the development of superior therapies. The microRNAs (miRNAs) belong to small non-coding RNAs that regulate post-transcriptional gene expression. Several shreds of evidence indicate that miRNAs play an important role in the pathogenesis of pancreatic cancer. Here we review the recent developments in miRNAs and their target role in the development, metastasis, migration, and invasion.


Subject(s)
MicroRNAs , Pancreatic Neoplasms , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms
8.
Sci Rep ; 12(1): 630, 2022 01 12.
Article in English | MEDLINE | ID: mdl-35022476

ABSTRACT

Purulia is a malaria-prone district in West Bengal, India, with approximately half of the blocks defined as malaria endemic. We analyzed the malaria case in each block of the Purulia district from January 1, 2016, to December 31, 2020. As per the API, 20 blocks of Purulia were assigned to four different categories (0-3) and mapped using ArcGIS software. An exponential decay model was fitted to forecast the trend of malaria cases for each block of Purulia (2021-2025). There was a sharp decrease in total malaria cases and API from 2016 to 2020 due to the mass distribution of LLINs. The majority of cases (72.63%) were found in ≥ 15-year age group. Males were more prone to malaria (60.09%). Malaria was highly prevalent among Scheduled Tribes (48.44%). Six blocks were reported in Category 3 (high risk) and none in Category 0 (no risk) in 2016, while no blocks were determined to be in Category 3, and three blocks were in Category 0 in 2020. The exponential decay model prediction is oriented towards gaining malaria-free status in thirteen blocks of Purulia by 2025. This study will incite the government to uphold and strengthen the current efforts to meet the malaria elimination goals.


Subject(s)
Malaria
10.
Avicenna J Med Biotechnol ; 12(2): 77-84, 2020.
Article in English | MEDLINE | ID: mdl-32431791

ABSTRACT

BACKGROUND: Dengue burden is increasing day-by-day globally. A rapid, sensitive, cost-effective early diagnosis kit is the need of the hour. In this study, a label-free electrochemical immunosensor was proposed for dengue virus detection. A modified Polyaniline (PANI) coated Glassy Carbon (GC) electrode, immobilized with DENV NS1 antibody was used to detect the circulating DENV NS1 antigen in both spiked and infected sample. METHODS: Cloning, purification and expression of DENV NS1 protein in Escherichia coli (E. coli) was performed and sensor design, PANI modification on GC electrode surface by electrochemical polymerization and immobilization of NS1 antibody on the modified electrode surface was done and finally the analytical performance of the electrochemical immunosensor was done using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). RESULTS: CV and EIS were used to study and quantitate the circulating DENV antigen. The calibration curve showed wide linearity, good sensitivity (Slope=13.8% IpR/ml.ng -1) and distribution of data with a correlation coefficient (R) of 0.997. A lower Limit of Detection (LOD) was found to be 0.33 ng.ml -1 which encourages the applicability of the sensor. CONCLUSION: Thus, a PANI based new electrochemical immunosensor has been developed which has the potential to be further modified for the development of cost effective, point of care dengue diagnostic kit.

11.
Oncotarget ; 9(30): 21322-21336, 2018 Apr 20.
Article in English | MEDLINE | ID: mdl-29765542

ABSTRACT

Reduced expression of Scaffold/Matrix Attachment Region Binding Protein 1 (SMAR1) is associated with various cancers resulting in poor prognosis of the diseases. However, the precise underlying mechanism elucidating the loss of SMAR1 requires ongoing study. Here, we show that SMAR1 is highly downregulated during aberrant Wnt3a signaling due to proteasomal degradation and predicted poor prognosis of colorectal cancer. However, substitution mutation (Arginine and Lysine to Alanine) in the D-box elements of SMAR1 viz. "RCHL" and "RQRL" completely abrogated its proteasomal degradation despite Wnt3a activity. SMAR1 inhibited Wnt/ß-catenin signaling by recruiting Histone deacetylase-5 to ß-catenin promoter resulting in reduced cell migration and invasion. Consequently, reduced tumor sizes in in-vivo NOD-SCID mice were observed that strongly associated with suppression of ß-catenin. However, loss of SMAR1 led to enriched H3K9 Acetylation in the ß-catenin promoter that further increased Wnt/ß-catenin signaling activities and enhanced colorectal cancer progression drastically. Using docking and isothermal titration calorimetric studies we show that small microbial peptides viz. AT-01C and AT-01D derived from Mycobacterium tuberculosis mask the D-box elements of SMAR1. These peptides stabilized SMAR1 expression that further inhibited metastatic SW480 colorectal cancer cell migration and invasion. Drastically reduced subcutaneous tumors were observed in in-vivo NOD-SCID mice upon administration of these peptides (25 mg/kg body weight) intraperitoneally. Taken together our structural studies, in-vitro and in-vivo results strongly suggest that the D-box elements of SMAR1 represent novel druggable targets, where the microbial peptides hold promise as novel colorectal cancer therapeutics.

12.
PLoS One ; 12(10): e0182443, 2017.
Article in English | MEDLINE | ID: mdl-29045410

ABSTRACT

Biological sex differences affect the course of HIV infection, with untreated women having lower viral loads compared to their male counterparts but, for a given viral load, women have a higher rate of progression to AIDS. However, the vast majority of data on viral evolution, a process that is clearly impacted by host immunity and could be impacted by sex differences, has been derived from men. We conducted an intensive analysis of HIV-1 gag and env-gp120 evolution taken over the first 6-11 years of infection from 8 Women's Interagency HIV Study (WIHS) participants who had not received combination antiretroviral therapy (ART). This was compared to similar data previously collected from men, with both groups infected with HIV-1 subtype B. Early virus populations in men and women were generally homogenous with no differences in diversity between sexes. No differences in ensuing nucleotide substitution rates were found between the female and male cohorts studied herein. As previously reported for men, time to peak diversity in env-gp120 in women was positively associated with time to CD4+ cell count below 200 (P = 0.017), and the number of predicted N-linked glycosylation sites generally increased over time, followed by a plateau or decline, with the majority of changes localized to the V1-V2 region. These findings strongly suggest that the sex differences in HIV-1 disease progression attributed to immune system composition and sensitivities are not revealed by, nor do they impact, global patterns of viral evolution, the latter of which proceeds similarly in women and men.


Subject(s)
HIV Infections/virology , HIV-1/physiology , Sex Characteristics , Cohort Studies , Disease Progression , Evolution, Molecular , Female , Glycosylation , HIV Envelope Protein gp120/genetics , HIV Infections/genetics , Humans , Likelihood Functions , Male , Nucleotides/genetics , Phylogeny , Time Factors , gag Gene Products, Human Immunodeficiency Virus/metabolism
13.
Cell Death Dis ; 8(6): e2882, 2017 06 15.
Article in English | MEDLINE | ID: mdl-28617439

ABSTRACT

The Tumor suppressor SMAR1 (scaffold matrix attachment region binding protein 1) has a crucial role in maintaining genomic stability, cell cycle progression and apoptosis.Our previous finding showed that it is highly suppressed in higher grade of cancer. However, the underlying mechanism of this suppression was not well understood. In this study, we show that SMAR1 expression levels are controlled at the proteasomal level by five RING finger E3 ubiquitin ligases including, Cdc20, a substrate receptor of ubiquitin ligase APC/C complex. We found that Cdc20 binds and promotes proteasomal degradation of SMAR1 in a D-box motif dependent manner. Further, our results demonstrated that Cdc20 promotes proteasomal degradation of SMAR1 through K48-linked specific polyubiquitylation, and that short hairpin RNA mediated inactivation of Cdc20 leads to significant stabilization of SMAR1. These findings suggest that Cdc20 is responsible for maintaining the cellular levels of SMAR1. However, since Cdc20 fails to target SMAR1 upon exposure to genotoxic stresses, SMAR1 helps to maintain genomic stability under these conditions through its DNA damage repair activity. Interestingly, Cdc20-mediated degradation of SMAR1 promotes cell migration and invasion.The reciprocal relationship of the duo is evident in breast cancer cell lines as well as in patient samples, suggesting that Cdc20 functions as an important negative regulator of SMAR1 in higher grades of cancer. Our study reveals for the first time, the molecular mechanism associated with lower levels of expression of the important tumor suppressor SMAR1 in higher grades of breast cancer.


Subject(s)
Cdc20 Proteins/metabolism , Cell Cycle Proteins/metabolism , DNA-Binding Proteins/metabolism , Neoplasms/metabolism , Nuclear Proteins/metabolism , Proteasome Endopeptidase Complex/metabolism , Anaphase-Promoting Complex-Cyclosome , Apoptosis , Breast Neoplasms/metabolism , Cell Cycle , Cell Line, Tumor , Cell Movement , Cell Nucleus/metabolism , Cytoplasm/metabolism , DNA Damage , DNA Repair , Female , HEK293 Cells , Humans , MCF-7 Cells , Neoplasm Invasiveness , Neoplasms/pathology , RNA, Small Interfering/metabolism , Ubiquitination
14.
J Mater Chem B ; 5(4): 785-796, 2017 Jan 28.
Article in English | MEDLINE | ID: mdl-32263847

ABSTRACT

It is essential for any antibacterial agent (for clinical applications) that it should have high and selective toxicity towards bacterial cells only, and should not affect the human cells at the concentration used. Graphene quantum dots (GQDs) have emerged as a potential candidate for biomedical applications. However, a simple, low cost, safe, easy to execute, one-step synthesis of uniform and monodispersed GQDs with selective toxicity towards bacterial cells rather than mammalian cells is difficult to achieve. Herein, we have reported a one-step, low-cost, aqueous-phase, simple approach for the complete conversion of multi-walled carbon nanotubes into water-dispersible GQDs with an average size of ∼3 nm using sodium bismuthate (NaBiO3) as a strong oxidant. The cyclic voltammetry and X-ray photoelectron spectroscopy results indicated that the as-synthesized GQDs suspension possess almost negligible amounts of metallic impurities. The cytotoxicity studies of GQDs against mammalian NIH 3T3 (mouse embryo fibroblast cells) and HEK 293T (human embryonic kidney cells) cells showed that the as-synthesized GQDs were non-cytotoxic up to the concentration of ∼200 µg mL-1. The antimicrobial study shows that the synthesized GQDs have high and selective toxicity towards bacterial cells with a minimum inhibitory concentration of ∼256 µg mL-1 for E. coli and B. subtilis and ∼512 µg mL-1 for P. aeruginosa and S. aureus. The scanning electron microscopy and atomic force microscopy images show extensive cell damage via the perturbation of bacterial cell walls, which was consistent with the enhancement of reactive oxygen species production by almost two times in the bacterial cells upon incubation with ∼256 µg mL-1 GQDs. Our study suggested that the as-synthesized GQDs can be used as a potential candidate for clinical applications as they possess high toxicity to bacterial cells and low toxicity to mammalian cells.

15.
Sci Rep ; 6: 33779, 2016 Sep 27.
Article in English | MEDLINE | ID: mdl-27671416

ABSTRACT

Chromatin architecture and dynamics are regulated by various histone and non-histone proteins. The matrix attachment region binding proteins (MARBPs) play a central role in chromatin organization and function through numerous regulatory proteins. In the present study, we demonstrate that nuclear matrix protein SMAR1 orchestrates global gene regulation as determined by massively parallel ChIP-sequencing. The study revealed that SMAR1 binds to T(C/G) repeat and targets genes involved in diverse biological pathways. We observe that SMAR1 binds and targets distinctly different genes based on the availability of p53. Our data suggest that SMAR1 binds and regulates one of the imperative microRNA clusters in cancer and metastasis, miR-371-373. It negatively regulates miR-371-373 transcription as confirmed by SMAR1 overexpression and knockdown studies. Further, deletion studies indicate that a ~200 bp region in the miR-371-373 promoter is necessary for SMAR1 binding and transcriptional repression. Recruitment of HDAC1/mSin3A complex by SMAR1, concomitant with alteration of histone marks results in downregulation of the miRNA cluster. The regulation of miR-371-373 by SMAR1 inhibits breast cancer tumorigenesis and metastasis as determined by in vivo experiments. Overall, our study highlights the binding of SMAR1 to T(C/G) repeat and its role in cancer through miR-371-373.

16.
Nanoscale ; 7(46): 19501-18, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26538278

ABSTRACT

Herein, we report the fabrication of a multifunctional nanoprobe based on highly monodispersed, optically and magnetically active, biocompatible, PEI-functionalized, highly crystalline ß-NaYF4:Gd(3+)/Tb(3+) nanorods as an excellent multi-modal optical/magnetic imaging tool and a pH-triggered intracellular drug delivery nanovehicle. The static and dynamic photoluminescence spectroscopy showed the presence of sharp emission peaks, with long lifetimes (∼3.5 milliseconds), suitable for optical imaging. The static magnetic susceptibility measurements at room temperature showed a strong paramagnetic signal (χ∼ 3.8 × 10(-5) emu g(-1) Oe(-1)). The nuclear magnetic resonance (NMR) measurements showed fair T1 relaxivity (r1 = 1.14 s(-1) mM(-1)) and magnetic resonance imaging gave enhanced T1-weighted MRI images with increased concentrations of ß-NaYF4:Gd(3+)/Tb(3+) making them suitable for simultaneous magnetic resonance imaging. In addition, an anticancer drug, doxorubicin (DOX) was conjugated to the amine-functionalized ß-NaYF4:Gd(3+)/Tb(3+) nanorods via pH-sensitive hydrazone bond linkages enabling them as a pH-triggered, site-specific drug delivery nanovehicle for DOX release inside tumor cells. A comparison between in vitro DOX release studies undertaken in normal physiological (pH 7.4) and acidic (pH 5.0) environments showed an enhanced DOX dissociation (∼80%) at pH 5.0. The multifunctional material was also applied as an optical probe to confirm the conjugation of DOX and to monitor DOX release via a fluorescence resonance energy transfer (FRET) mechanism. The DOX-conjugated ß-NaYF4:Gd(3+)/Tb(3+) nanorods exhibited a cytotoxic effect on MCF-7 breast cancer cells and their uptake by MCF-7 cells was demonstrated using confocal laser scanning microscopy and flow cytometry. The comparative cellular uptakes of free DOX and DOX-conjugated ß-NaYF4:Gd(3+)/Tb(3+) nanorods were studied in tumor microenvironment conditions (pH 6.5) using confocal imaging, which showed an increased uptake of DOX-conjugated ß-NaYF4:Gd(3+)/Tb(3+) nanorods. Thus, DOX-conjugated ß-NaYF4:Gd(3+)/Tb(3+) nanorods combining pH-triggered drug delivery, efficient luminescence and paramagnetic properties are promising for a potential multifunctional platform for cancer therapy, biodetection, and optical and magnetic resonance imaging.


Subject(s)
Doxorubicin , Fluorides , Gadolinium , Luminescent Measurements/methods , Magnetic Resonance Imaging/methods , Optical Imaging/methods , Terbium , Yttrium , Animals , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacology , Doxorubicin/chemistry , Doxorubicin/pharmacology , Female , Fluorides/chemistry , Fluorides/pharmacology , Gadolinium/chemistry , Gadolinium/pharmacology , Humans , Hydrogen-Ion Concentration , MCF-7 Cells , Mice , NIH 3T3 Cells , Terbium/chemistry , Terbium/pharmacology , Yttrium/chemistry , Yttrium/pharmacology
17.
J Virol ; 89(20): 10303-18, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26223634

ABSTRACT

UNLABELLED: To understand the interplay between host cytotoxic T-lymphocyte (CTL) responses and the mechanisms by which HIV-1 evades them, we studied viral evolutionary patterns associated with host CTL responses in six linked transmission pairs. HIV-1 sequences corresponding to full-length p17 and p24 gag were generated by 454 pyrosequencing for all pairs near the time of transmission, and seroconverting partners were followed for a median of 847 days postinfection. T-cell responses were screened by gamma interferon/interleukin-2 (IFN-γ/IL-2) FluoroSpot using autologous peptide sets reflecting any Gag variant present in at least 5% of sequence reads in the individual's viral population. While we found little evidence for the occurrence of CTL reversions, CTL escape processes were found to be highly dynamic, with multiple epitope variants emerging simultaneously. We found a correlation between epitope entropy and the number of epitope variants per response (r = 0.43; P = 0.05). In cases in which multiple escape mutations developed within a targeted epitope, a variant with no fitness cost became fixed in the viral population. When multiple mutations within an epitope achieved fitness-balanced escape, these escape mutants were each maintained in the viral population. Additional mutations found to confer escape but undetected in viral populations incurred high fitness costs, suggesting that functional constraints limit the available sites tolerable to escape mutations. These results further our understanding of the impact of CTL escape and reversion from the founder virus in HIV infection and contribute to the identification of immunogenic Gag regions most vulnerable to a targeted T-cell attack. IMPORTANCE: Rapid diversification of the viral population is a hallmark of HIV-1 infection, and understanding the selective forces driving the emergence of viral variants can provide critical insight into the interplay between host immune responses and viral evolution. We used deep sequencing to comprehensively follow viral evolution over time in six linked HIV transmission pairs. We then mapped T-cell responses to explore if mutations arose due to adaption to the host and found that escape processes were often highly dynamic, with multiple mutations arising within targeted epitopes. When we explored the impact of these mutations on replicative capacity, we found that dynamic escape processes only resolve with the selection of mutations that conferred escape with no fitness cost to the virus. These results provide further understanding of the complicated viral-host interactions that occur during early HIV-1 infection and may help inform the design of future vaccine immunogens.


Subject(s)
Epitopes, T-Lymphocyte/genetics , Genetic Fitness , HIV Seropositivity/virology , HIV-1/genetics , Immune Evasion/genetics , gag Gene Products, Human Immunodeficiency Virus/genetics , Amino Acid Sequence , Base Sequence , Entropy , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/immunology , Founder Effect , HIV Seropositivity/diagnosis , HIV Seropositivity/immunology , HIV Seropositivity/transmission , High-Throughput Nucleotide Sequencing , Humans , Interferon-gamma/pharmacology , Interleukin-2/pharmacology , Molecular Sequence Data , Mutation , Primary Cell Culture , Selection, Genetic , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/virology , Viral Load , gag Gene Products, Human Immunodeficiency Virus/immunology
18.
PLoS One ; 10(3): e0119218, 2015.
Article in English | MEDLINE | ID: mdl-25746435

ABSTRACT

Some individuals remain HIV-1 antibody and PCR negative after repeated exposures to the virus, and are referred to as HIV-exposed seronegatives (HESN). However, the causes of resistance to HIV-1 infection in cases other than those with a homozygous CCR5Δ32 deletion are unclear. We hypothesized that human p21WAF1/CIP1 (a cyclin-dependent kinase inhibitor) could play a role in resistance to HIV-1 infection in HESN, as p21 expression has been associated with suppression of HIV-1 in elite controllers and reported to block HIV-1 integration in cell culture. We measured p21 RNA expression in PBMC from 40 HESN and 40 low exposure HIV-1 seroconverters (LESC) prior to their infection using a real-time PCR assay. Comparing the 20 HESN with the highest exposure risk (median = 111 partners/2.5 years prior to the 20 LESC with the lowest exposure risk (median = 1 partner/2.5 years prior), p21 expression trended higher in HESN in only one of two experiments (P = 0.11 vs. P = 0.80). Additionally, comparison of p21 expression in the top 40 HESN (median = 73 partners/year) and lowest 40 LESC (median = 2 partners/year) showed no difference between the groups (P = 0.84). There was a weak linear trend between risk of infection after exposure and increasing p21 gene expression (R2 = 0.02, P = 0.12), but again only in one experiment. Hence, if p21 expression contributes to the resistance to viral infection in HESN, it likely plays a minor role evident only in those with extremely high levels of exposure to HIV-1.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21/genetics , HIV Seronegativity , RNA/genetics , Sexual Partners , HIV Infections/transmission , HIV Infections/virology , HIV-1 , Humans , Risk Factors , Unsafe Sex
19.
Chem Commun (Camb) ; 50(69): 9899-902, 2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25027189

ABSTRACT

A new Cu(II)-complex is used as a "Turn-On" luminescence probe for specific detection of endogenous Cys in live Hct116 cells and Cys present in human blood plasma without any interference from other amino acids, especially GSH and Hcy. Difference in the mechanistic pathway for Cys and His recognition is discussed.


Subject(s)
Coordination Complexes/chemistry , Copper/chemistry , Cysteine/analysis , Cysteine/blood , Fluorescent Dyes/chemistry , Histidine/analysis , Histidine/blood , Colorectal Neoplasms/chemistry , Fluorescence , HCT116 Cells , Humans , Luminescent Measurements
20.
Appl Biochem Biotechnol ; 168(5): 1076-85, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22935928

ABSTRACT

Antheraea mylitta, a tasar silk-producing insect of Saturniidae family, expresses a fungal protease inhibitor named as A. mylitta fungal protease inhibitor-1 (AmFPI-1). AmFPI-1 inhibits alkaline protease of Aspergillus oryzae but its mechanism of action is not known. To understand the mode of inhibition of AmFPI-1 against the fungal protease, it was purified from the hemolymph of A. mylitta larvae and inhibitory activity against A. oryzae protease was studied. Kinetic analysis of purified AmFPI-1 on alkaline protease of A. oryzae showed that AmFPI-1 acts as a canonical-type competitive inhibitor with equilibrium dissociation constant (K ( i )) of 60 nM. Expression of AmFPI-1 in different body tissues of fifth instar A. mylitta larvae was determined by real-time PCR, and the highest expression was observed in fat body followed by integument, silk gland, and gut, indicating that AmFPI-1 has pleiotropic functions including protection from invading fungi. The cDNA of AmFPI-1 was expressed in Escherichia coli, and recombinant His-tagged fusion protein was purified by Ni-NTA chromatography. Recombinant AmFPI-1 showed inhibitory activity against A. oryzae protease and suggested its use in various biological applications to prevent proteolysis.


Subject(s)
Fungi/enzymology , Insect Proteins , Moths , Recombinant Proteins , Animals , Aspergillus oryzae/drug effects , Gene Expression , Insect Proteins/biosynthesis , Insect Proteins/chemistry , Insect Proteins/genetics , Kinetics , Moths/enzymology , Moths/genetics , Protease Inhibitors/chemistry , Protease Inhibitors/metabolism , Protease Inhibitors/pharmacology , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics
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