MT-2 Cell Line Research Articles

Hyperbaric hyperoxia exposure in suppressing human immunodeficiency virus replication: An experimental in vitro in peripheral mononuclear blood cells culture.

Cellular immune has an important role in response HIV infection, which is attack the infected cells to activate signaling molecule. Hyperbaric Oxygen (HBO) worked as complementary treatment for HIV infection. The production of ROS and RNS molecules during hyperbaric exposure can affect gene expression which contributes to cellular adaptative response. This study was conducted to explore the mechanisms of cellular adaptive response to HIV infection during hyperbaric exposure. This study was carried on in vitro using healthy volunteers’ PBMCs (Peripheral Blood Mononuclear Cells) cultures infected with HIV-1. The study was conducted as a posttest only group design. The experimental unit was PBMC from venous blood of healthy volunteers which were cultured in vitro and infected by co-culturing with HIV- 1 in MT4 cell line. The experimental unit consist of treatment and control group. Each group examined the expression of transcription factor NFκB, Interferon α, reverse transcriptase inhibitors (p21), and the amount of HIV-1 p24 antigen. There were increasingly significant differences in the expression of the trancription factor of NFκB, p21, andHIV-1 p24 antigen,as well as mRNA transcription of interferon α2 between treatment and controlgroup. By decreasing p24 antigen showed that HBO exposure was able to suppress HIV-1 replication. The exposure to hyperbaric oxygen at the pressure of 2.4 ATAand 98% oxygen wasable to produce ROS and RNS molecules, which play a role in cellular adaptive responses through increasing the expression of nfĸb, p21 and mRNA of interferon α2 plays a role in inhibition mechanism of HIV-1 replication in cells.

Synthetic (E)-3-Phenyl-5-(phenylamino)-2-styryl-1,3,4-thiadiazol-3-ium Chloride Derivatives as Promising Chemotherapy Agents on Cell Lines Infected with HTLV-1.

Synthesis of four compounds belonging to mesoionic class, (E)-3-phenyl-5-(phenylamino)-2-styryl-1,3,4-thiadiazol-3-ium chloride derivatives (5a–d) and their biological evaluation against MT2 and C92 cell lines infected with human T-cell lymphotropic virus type-1 (HTLV-1), which causes adult T-cell leukemia/lymphoma (ATLL), and non-infected cell lines (Jurkat) are reported. The compounds were obtained by convergent synthesis under microwave irradiation and the cytotoxicity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Results showed IC50 values of all compounds in the range of 1.51–7.70 μM in HTLV-1-infected and non-infected cells. Furthermore, it was observed that 5b could induce necrosis after 24 h for Jurkat and MT2 cell lines. The experimental (fluorimetric method) and theoretical (molecular docking) results suggested that the mechanism of action for 5b could be related to its capacity to intercalate into DNA. Moreover, the preliminary pharmacokinetic profile of the studied compounds (5a–d) was obtained through human serum albumin (HSA) binding affinity using multiple spectroscopic techniques (circular dichroism, steady-state and time-resolved fluorescence), zeta potential and molecular docking calculations. The interaction HSA:5a–d is spontaneous and moderate (Ka ~ 104 M−1) via a ground-state association, without significantly perturbing both the secondary and surface structures of the albumin in the subdomain IIA (site I), indicating feasible biodistribution in the human bloodstream.

Enhanced expression of nicotinamide nucleotide transhydrogenase (NNT) and its role in a human T cell line continuously exposed to asbestos

The effects of asbestos fibers on human immune cells have not been well documented. We have developed a continuously exposed cell line model using the human T-lymphotropic virus 1 (HTLV-1)-immortalized human T cell line MT-2. Sublines continuously exposed to chrysotile (CH) or crocidolite (CR) showed acquired resistance to asbestos-induced apoptosis following transient and high-dose re-exposure with fibers. These sublines in addition to other immune cells such as natural killer cells or cytotoxic T lymphocytes exposed to asbestos showed a reduction in anti-tumor immunity. In this study, the expression of genes and molecules related to antioxidative stress was examined. Furthermore, complexes related to oxidative phosphorylation were investigated since the production of reactive oxygen species (ROS) is important when considering the effects of asbestos in carcinogenesis and the mechanisms involved in resistance to asbestos-induced apoptosis. In sublines continuously exposed to CH or CR, the expression of thioredoxin decreased. Interestingly, nicotinamide nucleotide transhydrogenase (NNT) expression was markedly enhanced. Thus, knockdown of NNT was then performed. Although the knockdown clones did not show any changes in proliferation or occurrence of apoptosis, these clones showed recovery of ROS production with returning NADPH/NADP+ ratio that increased with decreased production of ROS in continuously exposed sublines. These results indicated that NNT is a key factor in preventing ROS-induced cytotoxicity in T cells continuously exposed to asbestos. Considering that these sublines showed a reduction in anti-tumor immunity, modification of NNT may contribute to recovery of the anti-tumor effects in asbestos-exposed T cells.

Potent HIV-1 Protease Inhibitors Containing Carboxylic and Boronic Acids: Effect on Enzyme Inhibition and Antiviral Activity and Protein-Ligand X-ray Structural Studies.

We report the synthesis and biological evaluation of phenylcarboxylic acid and phenylboronic acid containing HIV-1 protease inhibitors and their functional effect on enzyme inhibition and antiviral activity in MT-2 cell lines. Inhibitors bearing bis-THF ligand as P2 ligand and phenylcarboxylic acids and carboxamide as the P2' ligands, showed very potent HIV-1 protease inhibitory activity. However, carboxylic acid containing inhibitors showed very poor antiviral activity relative to carboxamide-derived inhibitors which showed good antiviral IC50 value. Boronic acid derived inhibitor with bis-THF as the P2 ligand showed very potent enzyme inhibitory activity, but it showed lower antiviral activity than darunavir in the same assay. Boronic acid containing inhibitor with a P2-Crn-THF ligand also showed potent enzyme Ki but significantly decreased antiviral activity. We have evaluated antiviral activity against a panel of highly drug-resistant HIV-1 variants. One of the inhibitors maintained good antiviral activity against HIVDRVRP20 and HIVDRVRP30 viruses. We have determined high resolution X-ray structures of two synthetic inhibitors bound to HIV-1 protease and obtained molecular insight into the ligand-binding site interactions.

505P - High NAMPT expression and anti-tumour activity of NAMPT inhibitor in adult T-cell leukemia/lymphoma

BackgroundAdult T-cell leukemia/lymphoma (ATL) is a malignancy of mature T lymphocytes induced by human T-cell leukemia virus-1, and has a poor outcome. New molecular targets for the prevention and treatment of ATL are urgently needed. We previously reported that Sirtuin 1, a nicotinamide adenine dinucleotide (NAD+)-dependent histone/protein deacetylase, is highly expressed in primary acute-type ATL cells. NAD+ biosynthesis via nicotinamide phosphoribosyltransferase (NAMPT) modulates Sirtuin 1 activity. Here, we examined the expression and effects of inhibiting NAMPT, a rate-limiting. MethodsPeripheral blood mononuclear cells from ATL patients were carried out in accordance with the guidelines of the Committees for Ethical Review of Research involving Human Subjects at Kagoshima University Hospital. Cell viability was evaluated in the S1T cell line derived from an ATL patient, MT-2 cell line derived from normal human leukocytes transformed by leukemic T-cells from an ATL patient, and primary ATL cells. Animal experiments were approved by the Animal Care and Use Committee of Rakuno Gakuen University in accordance with the Guide for the Care and Use of Laboratory Animals. ResultsPeripheral blood mononuclear cells from acute-type ATL patients expressed significantly higher NAMPT protein levels than cells from healthy controls. FK866, a NAMPT inhibitor, induced apoptosis in fresh ATL cells ex vivo and HTLV-1-infected T-cell lines in vitro, which was accompanied by NAD+ depletion, activation of caspases, DNA fragmentation, and disruption of mitochondrial transmembrane potential. A pan-caspase inhibitor failed to prevent the FK866-induced cell death, while FK866 increased endonuclease G, a caspase-independent cell death mediator. Intriguingly, FK866 activated autophagy, revealed by increased LC3-II protein levels and autophagic flux. Thus, FK866 simultaneously activated apoptosis and autophagy. Finally, FK866 treatment markedly decreased human ATL tumor xenograft growth in immunodeficient mice. ConclusionsThese results demonstrate that NAMPT inhibition induces autophagy and caspase-dependent and -independent cell death in ATL cells, suggesting a novel therapeutic strategy for patients with this fatal disease. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Effects of interferon inducible protein 16 (IFI16) on viral protein and pro-inflammatory cytokine expression in human T-cell leukemia virus type 1 (HTLV-1)-positive T cells

Objective To investigate the effects of interferon inducible protein 16 (IFI16), a cytosolic DNA sensor, on the expression of human T-cell leukemia virus type 1 (HTLV-1) proteins and pro-inflammatory cytokines in adult HTLV-1-positive T cells. Methods IFI16 expression in different HTLV-1-positive T cell lines was detected by immunoblot assay. Specific siRNA targeting the IFI16 gene was constructed and the gene silencing efficiency was detected by immunoblot assay. Expression of HTLV-1 Tax protein at mRNA and protein levels was respectively detected by real-time PCR and immunoblot assay after knocking down the expression of IFI16 in HTLV-1-positive T cells with siRNA. Expression of interferon (IFN)-α, IFN-γ, tumor necrosis factor (TNF)-α, Tax and Env were detected by real-time PCR. Results Compared with the HTLV-1-negative T cell line Jurkat, IFI16 expression was enhanced in the HTLV-1-positive T cell lines MT2, MT4 and C8166. Tax expression was increased, while that of IFN-α, IFN-γ and TNF-α was decreased in MT2 and MT4 cells after silencing the expression of IFI16 with siRNA. Conclusions IFI16 expression was increased in HTLV-1-positive MT2 and MT4 cells. Meanwhile, IFI16 promoted the production of interferon and pro-inflammatory cytokines and inhibited the expression of HTLV-1 proteins. Key words: Interferon inducible protein 16 (IFI16); Human T-cell leukemia lymphoma virus type 1 (HTLV-1); Interferon; T lymphocyte; TNF-α

Flow cytometric methodology for the detection of de novo human T-cell leukemia virus -1 infection in vitro: A tool to study novel infection inhibitors

Methodology to detect and study de novo human T-cell leukemia virus (HTLV)-1 infection is required to further our knowledge of the viruses’ mechanisms of infection and to study potential therapeutic interventions. Whilst methodology currently exists, utilisation of an anti-Tax antibody to detect de novo Tax expression in permissive cells labelled with cell tracker allowing for the detection by flow cytometry of new infection after co-culture with donor cell lines productively infected with HTLV-1 is an alternative strategy. Using this methodology, we have been able to detect de novo infection of the T cell line HUT78 following co-culture with the productively infected HTLV-1 donor cell line MT-2 and to confirm that infection can be effectively blocked with well characterised infection inhibitors. This methodology will benefit experimental studies examining HTLV infection in vitro and may aid identification of therapeutic agents that block this process.

Design, Synthesis, Antimicrobial, and Anticancer Activities of Acridine Thiosemicarbazides Derivatives.

Background: Acridine and thiourea derivatives are important compounds in medicinal chemistry due to their diverse biological properties including anticancer and antimicrobial effects. However, literature reveals some side effects associated with use of acridines. It is suggested that hybrid molecules may reduce the side effects and enhance the beneficial properties due to synergistic activity. The objectives of the present study are to synthesize and evaluate the anticancer and antimicrobial properties of new hybrids of acridine thiosemicarbazides derivatives. Results: The structures of the synthesized compounds 4a–4e were elucidated by MS and NMR spectra. In antimicrobial assay, Compound 4c exhibited potent antimicrobial activity compared to the other four compounds. In anticancer studies, we observed that compounds 4a, 4b, 4d and 4e exhibited high cytotoxicity against the MT-4 cell line, with IC50 values of 18.42 ± 1.18, 15.73 ± 0.90, 10.96 ± 0.62 and 11.63 ± 0.11 μM, respectively. The evaluation of anticancer effects, and the associated mechanism reveals that, the anticancer activities may be related to Topo I inhibitory activity, apoptosis and cell-cycle. Molecular docking studies revealed that the presence of planar naphtho-fused rings and a flexible thiourea group together, could improve DNA-intercalation and inhibition of DNA-Topo I activity. Conclusions: The results of this study demonstrate that the rational design of target derivatives as novel antimicrobial or antitumor leads is feasible.

REPLICATION OF HIV-1 SUBTYPE A6 IN THE PRESENCE OF HORMONES INCLUDED IN THE MODERN HORMONAL CONTRACEPTIVES

Aim. To study how female hormones included in oral contraceptives (β-estradiol and progesteron) affect HIV-1 replication and efficacy of antiviral drugs. Material and methods. Peripheral blood mononuclear cells (PBMC) and cell lines MT-4, Jurkat were infected with HIV-1 (subtype A6). Afterwards the cells were cultured for 6 days in the presence of β-estradiol/progesteron with or without the presence of antiretroviral drugs Lamivudin (3TC), Etravirin(ETR) and Indinavir (IDV), which are widely used for HIV treatment. Virus production was monitored by p24 levels in culture supernatants on day 6. The experemints were performed in eight repetitions. Results. There was a 1,3-1,8-fold increase of virus replication in the presence of high concentrations of both hormones (26,136 μg/ml). Incomplete suppression of viral replication was observed when infected cells were co-cultivated in the presence of hormones (26 μg, 136 μg) and antiretroviral drugs. The mean suppression rate of viral replication for β-estradiol was 77.3% and 69.8% for progesterone. However, in the absence of hormones the virus production was completely suppressed by those drugs. Conclusion. The high concentrations of steroid hormones induce HIV-1 replication and as a result reduce the efficacy of antiretroviral drugs NVP and IDV in vitro. Thus it is advisable for women at high risk of HIV infection to monitor hormone levels that change during the menstrual cycle and pregnancy before prescribing hormonal contraception.

Diversity of cell phenotypes among MT-2 cell lines affects the growth of U937 cells and cytokine production.

We previously reported the diversity of structure and integration sites of human T-cell leukemia virus type 1 (HTLV-1) provirus among different MT-2 cell lines. This raised the question as to whether cell phenotypes also differed among MT-2 cell lines. The influence of two different MT-2 cell lines (MT-2J and MT-2B) on the growth of the promonocytic leukemia cell line, U937, was investigated. Protein levels and mRNA expression of cytokines were also investigated. In addition, Western blot analysis of HTLV-1 regulatory proteins, Tax and HBZ, was also performed. Culture supernatant from MT-2B, but not MT-2J, cells showed marked suppressive effects on U937 cell growth. MT-2B showed high tumor necrosis factor (TNF)-α, TNF-β, and interferon (IFN)-γ both in protein levels of the culture supernatant and mRNA levels of the cells. Analysis using recombinant cytokines indicated that the suppressive effects of MT-2B were due, at least in part, to high levels of TNF-β and its synergic effects with IFN-γ in the culture supernatant. Protein levels of HTLV-1 Tax and HBZ were higher in MT-2B than those in MT-2J cells. These molecules have been reported to affect the cytokine production of HTLV-1 infected cells; therefore, the difference in these molecules may have accounted for the differences in cytokine production between MT-2J and MT-2B cells. Furthermore, because MT-2 cells showed a large variation of integrated HTLV-1 proviruses as well as cell phenotypes, it is important to exercise caution in the assessment and interpretation of experimental data from MT-2 cells.

In vitro study of toxicity of hybrid gold-polymer composites

The purpose of the present study was to evaluate the toxicity of gold nanoparticles (AuNPs) incorporated into branched polymer matrices Dextran-graft-Polyacrylamide on cancer cells of different origin. The study was performed on breast cancer MCF-7 cell line and its two sublines MCF-7/Dox and MCF-7/DDP resistant to Dox and DDP, respectively and MT-4 (human T-cell leukemia) cell line. All cells were treated with copolymer D-g-Pаа alone and nanosystem, containing D-g-Pаа/AuNPs. Results of our study proved low toxicity of examined compounds even in high doses. Nanosystems, containing AuNP exhibited more pronounced cytotoxic effects on cancer cells in comparison to D70-Pаа alone.

In vivo and in vitro immunogenicity of novel MHC class I presented epitopes to confer protective immunity against chronic HTLV-1 infection

Human T-cell leukemia virus type 1 (HTLV-1) has infected as many as 10 million people worldwide. While 90% are asymptomatic, 5% develop severe diseases including adult T-cell leukemia/lymphoka (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). No vaccine against HTLV-1 exists, and screening programs are not universal. However, patients with chronic HTLV-1 infection have high frequencies of HTLV-1-activated CD8+ T cells, and the two main HLA alleles (A2, A24) are present in 88% of infected individuals. We thus utilized an immunoproteomics approach to characterize MHC-I restricted epitopes presented by HLA-A2+, A24+ MT-2 and SLB-1 cell lines. Unlike traditional motif prediction algorithms, this approach identifies epitopes associated with cytotoxic T-cell responses in their naturally processed forms, minimizing differences in antigen processing and protein expression levels. Out of nine identified peptides, we confirmed six novel MHC-I restricted epitopes that were capable of binding HLA-A2 and HLA-A24 alleles and used in vitro and in vivo methods to generate CD8+ T cells specific for each of these peptides. MagPix MILLIPLEX data showed that in vitro generated epitope-specific CD8+ T cells secreted IFN-ɣ, granzyme B, MIP-1α, TNF-α, perforin and IL-10 when cultured in the presence of MT-2 cell line. Degranulation assay confirmed cytotoxic response through surface expression of CD107 on CD8+ T cells when cultured with MT-2 cells. A CD8+ T-cell killing assay indicated significant antiviral activity of CD8+ T cells specific against all identified peptides. In vivo generated CD8+ T cells similarly demonstrated immunogenicity on ELISpot, CD107 degranulation assay, and MagPix MILLIPLEX analysis. These epitopes are thus candidates for a therapeutic peptide-based vaccine against HTLV-1, and our results provide preclinical data for the advancement of such a vaccine.

CYTOTOXIC PROPERTIES OF TRITERPENE SAPONIN TAUROSID SX1 AND ITS EFFECT ON HUMAN IMMUNODEFICIENCY VIRUS AND INFLUENZA VIRUS INFECTION IN MICE.

Triterpene saponin Taurosid Sx1 purified from leaves of the plant Crimean Ivy Hedera taurica Carr. (Araliaceae) was evaluated for its cytotoxic activity against lymphoblastoid cell lines MT-4, Jurkat-tat, U937, and human peripheral blood monocytes. The ability of saponin to influence HIV-1 replication was studied as well. In addition, the ability of Taurosid Sx1 to increase survival of mice infected with influenza virus А/WSN/1/33(H1N1) and its capacity for strengthening the immune responses in mice immunized with the influenza vaccine Grippol® have been studied. Taurosid Sx1 has been shown to inhibit MT-4 cell line at 25 μg ml-1 concentration, IC50 33,3 μmol l-1 (MTT assay). The saponin concentration of 5 μg ml-1 was non-toxic for all the cell lines studied and demonstrated a moderate inhibitory effect on HIV p24 production in Jurkat-tat cells. In the lower concentrations Taurosid Sx1 did not stimulate HIV p24 production. It was shown that oral administration of 200 μg Taurosid Sx1 to the influenza virus infected mice caused 1.5-fold increase in their survival. Taurosid Sx1 given orally amplified immunopotentiating ability of an intramusculary administered subunit influenza vaccine. Antibody production was significantly higher in animals fed Taurosid Sx1 after primary or secondary immunizatuion. In mice given 2 doses of vaccine, from 1 to 3 weeks apart, feeding 200 μg saponin resulted in 2 to 10-fold enhancement in production of anti-H1, anti-H3, and anti-inluenza type B hemagglutinin antibodies. Thus, Taurosid Sx1 can be considered as low-toxic promising immunopotentiating agent uncapable of enhancing HIV-1 replication.

ANTIVIRAL ACTIVITY OF Justicia gendarussa Burm.f. LEAVES AGAINST HIV-INFECTED MT-4 CELLS.

Backgrounds:Justicia gendarussa Burm.f. has been known to have anti-HIV activity. This study was conducted to evaluate the effect of incubation time on the antiviral activity of the J. gendarussa leaves extract on HIV-infected MT-4 cells in vitro. Molecular docking test was also conducted to determine the interaction of alkaloids and flavonoids on the J. gendarussa leaves against HIV-1 reverse transcriptase receptor. It is expected that this research will provide scientific information on the development of J. gendarussa leaves as an anti-HIV drug.Materials and Methods:In the activity test, the effect of incubation time on the antiviral activity of J. gendarussa leaves on HIV-infected MT-4 cells were evaluated. During the activity test, a parameter of cytolysis effect inhibition on MT-4 cell line was observed after 4 days and 6 days incubation period. The molecular docking test is performed by using Molegro Virtual Docker software to determine the interaction of alkaloid and flavonoid compounds of J. gendarussa leaves with HIV-1 reverse transcriptase receptor.Results:The incubation time influences the CC50 and EC50 value. Fractionated-70% ethanol extract of J. gendarussa leaves showed a higher anti-HIV activity with EC50 = 3.045 x 10-9 μg/mL, SI = 6.309 x 1012 (4 days of incubation) and EC50 = 6.066 μg/mL, SI = 58494.845 (6 days of incubation). From molecular docking test, it was found that flavonoid of J. gendarussa leaves could inhibit the activity of HIV reverse transcriptase enzyme.Conclusion:Fractionated-70% ethanol extract of J. gendarussa has potential as an anti-HIV.

IN VITRO STUDIES ON HEME OXYGENASE-1 AND P24 ANTIGEN HIV-1 LEVEL AFTERHYPERBARIC OXYGEN TREATMENTOFHIV-1 INFECTED ON PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS).

Background:Heme oxygenase-1 (HO-1) is a protein secreted by immune cells as a part of immune response mechanism.HO-1 can be induced by variety agents that causingoxidative stress, such as exposure to 100% oxygenat2,4 ATA pressure.It plays a vital role in maintaining cellular homeostasis.This study was conducted to identify the effect of hyperbaric oxygen exposure in cultured ofPBMCthat infected by HIV-1.Material and Methods:Primary culture of PBMCs were isolated from 16 healthy volunteers and HIV-1 infected MT4 cell line by co-culture. The PBMCs were aliquoted into two wells as control group and treatment group. The 16 samples of HIV-1 infected PBMCwere exposed to oxygen at 2,4 ATA in animal hyperbaric chamber forthree times in 30 minutes periods with 5 minutes spacing period, that called 1 session.The Treatment done on 5 sessions within 5 days. 16 samples of HIV-1 infected PMBCs that have no hyperbaric treatment became control group.The supernatant were measured the HO-1 production by ELISA andmRNA expression of HO-1 by real time PCR and the number ofantigen p24 HIV-1by ELISA.Results:The result showed that there was no increasing of HO-1 at both mRNA level and protein level, there was a decreasing number of antigen p24 HIV-1 at the treatment group. In addition, hyperbaric exposure could not increase the expression of HO-1, more over the viral replication might be reduced by other mechanism.Conclusions:Hyperbaric oxygen could increases cellular adaptive response of PBMCs infected HIV-1 through increased expression of proteins that can inhibit HIV viralreplication.

Inflammatory Alteration of Human T Cells Exposed Continuously to Asbestos.

Asbestos is a known carcinogen and exposure can lead to lung cancer and malignant mesothelioma. To examine the effects of asbestos fibers on human immune cells, the human T cell leukemia/lymphoma virus (HTLV)-1 immortalized human T cell line MT-2 was employed. Following continuous exposure to asbestos fibers for more than eight months, MT-2 sublines showed acquisition of resistance to asbestos-induced apoptosis with decreased death signals and increased surviving signals. These sublines showed various characteristics that suggested a reduction in anti-tumor immunity. On the other hand, inflammatory changes such as expression of MMP7, CXCR5, CXCL13 and CD44 was found to be markedly higher in sublines continuously exposed to asbestos compared with original MT-2 cells. All of these molecules contribute to lung inflammation, T and B cell interactions and connections between mesothelial cells and T cells. Thus, further investigation focusing on these molecules may shed light on the role of chronic inflammation caused by asbestos exposure and the occurrence of malignant mesothelioma. Finally, regarding peripheral T cells from healthy donors (HD) and asbestos-exposed patients with pleural plaque (PP) or malignant pleural mesothelioma (MPM), following stimulation of CD4+ T cells, T cells from MPM patients showed reduced potential of interferon (IFN)-γ expression. Moreover, levels of interleukin (IL)-6, one of the most important cytokines in chronic inflammation, in cultured supernatants were higher in PP and MPM patients compared with HD. Overall, asbestos-induced chronic inflammation in the lung as well as the pleural cavity may facilitate the onset of asbestos-induced cancers due to alterations in the interactions among fibers, immune cells such as T and B cells and macrophages, and mesothelial and lung epithelial cells. Further investigations regarding chronic inflammation caused by asbestos fibers may assist in identifying molecular targets for preventive and therapeutic strategies related to the effects of asbestos exposure.

Application of MT-4 neoplasm cell line for the immunomodulating activity study of patients plasma with HIV-infection.

It was studied in vitro the immunomodulatory effect of plasma HIV-infected individuals on expression of activation markers when used as a model neoplastic cell line MT-4. Carrying out researches indicated the variation in expression of the activation markers CD28+, CD38+, HLA-DR+ и CD69+. Change dynamics of these indices showed that these proteins can to consider as markers for level evaluation of patients immune system during used of plasma HIV-infected individuals with and without antiretroviral treatment (ART). Analysis revealed reduction of cells activation potential in plasma of patients with ART presence and rise without treatment. Examinations of the expression proteins CD28, CD38, HLA-DR и CD69 MT-4 cells and plasma of patients with HIV-infection application can have prognostic value for infection monitoring and efficacy of different therapeutic approaches.

Synthesis, Biological Evaluation, and Molecular Docking Studies of Novel 4-[4-Arylpyridin-1(4H)-yl]benzoic Acid Derivatives as Anti-HIV-1 Agents.

The structural similarities between N1 substituted 1,4-dihydropyridines and the known gp41 inhibitors, NB-2 and NB-64, were considered in the current research for the design of some novel anti-HIV-1 agents. A series of novel 4-[4-arylpyridin-1(4H)-yl]benzoic acid derivatives were synthesized and after a comprehensive structural elucidation were screened for in vitro anti-HIV-1 activity. Most of the tested compounds displayed moderate to good inhibitory activity against HIV-1 growth and were evaluated for in vitro cytotoxic activity using XTT assay at the concentration of 100 μm. Among the tested compounds, 1c, 1d and 1e showed potent anti-HIV-1 activity against P24 expression at 100 μm with inhibition percentage of 84.00%, 76.42% and 80.50%, respectively. All the studied compounds possessed no significant cytotoxicity on MT-2 cell line. The binding modes of these compounds to gp41 binding site were determined through molecular docking study. Docking studies proved 1a as the most potent compound and binding maps exhibited that the activities might be attributed to the electrostatic and hydrophobic interactions and additional H-bonds with the gp41 binding site. The Lipinski's 'rule of five' and drug-likeness criteria were also calculated for the studied compounds. All derivatives obeyed the Lipinski's 'rule of five' and had drug-like features. The findings of this study suggest that novel 4-[4-arylpyridin-1(4H)-yl]benzoic acid might be a promising scaffold for the discovery and development of novel anti-HIV-1 agents.

The role of the glycosyl moiety of myricetin derivatives in anti-HIV-1 activity in vitro

BackgroundPlant extracts are sources of valuable compounds with biological activity, especially for the anti-proliferative activity against pathogens or tumor cells. Myricetin is a flavonoid found in several plants that has been described as an inhibitor of Human immunodeficiency virus type 1 (HIV-1) through its action against the HIV reverse transcriptase, but myricetin derivatives have not been fully studied. The aim of this study was to evaluate the anti-HIV-1 activity of glycosylated metabolites obtained from Marcetia taxifolia and derived from myricetin: myricetin rhamnoside and myricetin 3-(6-rhamnosylgalactoside).MethodsCompounds were obtained from organic extracts by maceration of aerial parts of M. taxifolia. All biological assays were performed in the MT4 cell line. Antiviral activity was measured as inhibition of p24 and reverse transcriptase with a fluorescent assay.ResultsBoth flavonoids have antiviral activity in vitro, with an EC50 of 120 µM for myricetin 3-rhamnoside (MR) and 45 µM for myricetin 3-(6-rhamnosylgalactoside) (MRG), both significantly lower than the EC50 of myricetin (230 µM). Although both compounds inhibited the reverse transcriptase activity, with an IC50 of 10.6 µM for MR and 13.8 µM for MRG, myricetin was the most potent, with an IC50 of 7.6 µM, and an inhibition greater than 80%. Molecular docking approach showed correlation between the free energy of binding with the assays of enzyme inhibition.ConclusionsThe results suggest that glycosylated moiety might enhance the anti-HIV-1 activity of myricetin, probably by favoring the internalization of the flavonoid into the cell. The inhibition of the HIV-1 reverse transcriptase is likely responsible for the antiviral activity.

Early growth response gene-1 regulates host cell autophagy in HTLV-1 infection

Objective To investigate the influence of early growth response gene-1 (EGR1) on the autophagy of host cells following infection with human T cell leukemia virus type 1 (HTLV-1). Methods A HTLV-1-positive cell line MT2 was co-cultured with HeLa cells for 24 h to construct the virus early infection model. Immunoblotting assay was used to detect the expression of HTLV-1 core protein p19 and EGR1. Luciferase reporter gene analysis was used to detect the transcriptional activity of 5′-regulatory sequence of EGR1 at different time points after co-culturing. An effective small interfering RNA (siRNA) targeting EGR1 was screened out and transfected into HeLa cells by Lipofectamine 2000. Then the transfected HeLa cells were co-cultured with the HTLV-1-positive cell line MT2 for 24 h. Immunoblotting assay was used to detect HTLV-1 core protein p19, EGR1 and autophagy-related protein LC3. Real-time PCR was performed to detect viral load. Autophagosome was analyzed by immunofluorescence after co-culturing. Results The expression of EGR1 and the transcriptional activity of pEGR1-luc gradually increased after co-culturing HeLa cells with MT2 cells for 8 h (P<0.01). The expression of EGR1 was positively correlated with host cell autophagy following HTLV-1 infection. The effective siRNA for silencing the expression of EGR1 was obtained and named as siE2. The viral load, the expression of HTLV-1 core protein p19 and the proportion of LC3B/LC3A in the co-culture model were markedly down-regulated by RNA interference with siE2, which was concomitant with a persistent decrease of intracellular autophagosome (P<0.01). Conclusion EGR1 is associated with host cell autophagy and viral replication in HTLV-1 infection. Key words: Early growth response gene-1; Human T-cell leukemia virus type 1; Autophagy; Virus replication