The effect of omega-3 fatty acid supplementation on clinical and biochemical parameters of critically ill patients with COVID-19: a randomized clinical trial.

BACKGROUND: Omega-3 polyunsaturated fatty acids (n3-PUFAs) may exert beneficial effects on the immune system of patients with viral infections. This paper aimed to examine the effect of n3-PUFA supplementation on inflammatory and biochemical markers in critically ill patients with COVID-19. METHODS: A double-blind, randomized clinical trial study was conducted on 128 critically ill patients infected with COVID-19 who were randomly assigned to the intervention (fortified formula with n3-PUFA) (n = 42) and control (n = 86) groups. Data on 1 month survival rate, blood glucose, sodium (Na), potassium (K), blood urea nitrogen (BUN), creatinine (Cr), albumin, hematocrit (HCT), calcium (Ca), phosphorus (P), mean arterial pressure (MAP), O2 saturation (O2sat), arterial pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3), base excess (Be), white blood cells (WBCs), Glasgow Coma Scale (GCS), hemoglobin (Hb), platelet (Plt), and the partial thromboplastin time (PTT) were collected at baseline and after 14 days of the intervention. RESULTS: The intervention group had significantly higher 1-month survival rate and higher levels of arterial pH, HCO3, and Be and lower levels of BUN, Cr, and K compared with the control group after intervention (all P < 0.05). There were no significant differences between blood glucose, Na, HCT, Ca, P, MAP, O2sat, PO2, PCO2, WBCs, GCS, Hb, Plt, PTT, and albumin between two groups. CONCLUSION: Omega-3 supplementation improved the levels of several parameters of respiratory and renal function in critically ill patients with COVID-19. Further clinical studies are warranted. Trial registry Name of the registry: This study was registered in the Iranian Registry of Clinical Trials (IRCT); Trial registration number: IRCT20151226025699N3; Date of registration: 2020.5.20; URL of trial registry record: https://en.irct.ir/trial/48213.

Antiviral activity of Sambucus FormosanaNakai ethanol extract and related phenolic acid constituents against human coronavirus NL63.

Human coronavirus NL63 (HCoV-NL63), one of the main circulating HCoVs worldwide, causes respiratory tract illnesses like runny nose, cough, bronchiolitis and pneumonia. Recently, a severe respiratory illness outbreak of HCoV-NL63 has been reported in a long-term care facility. Sambucus FormosanaNakai, a species of elderberry, is a traditional medicinal herb with anti-inflammatory and antiviral potential. The study investigated the antiviral activity of Sambucus FormosanaNakai stem ethanol extract and some phenolic acid constituents against HCoV-NL63. The extract was less cytotoxic and concentration-dependently increased anti-HCoV-NL63 activities, including cytopathicity, sub-G1 fraction, virus yield (IC50 = 1.17 µg/ml), plaque formation (IC50 = 4.67 µg/ml) and virus attachment (IC50 = 15.75 µg/ml). Among the phenolic acid constituents in Sambucus FormosanaNakai extract, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity that was ranked in the following order of virus yield reduction: caffeic acid (IC50 = 3.54 µM) > chlorogenic acid (IC50 = 43.45 µM) > coumaric acid (IC50 = 71.48 µM). Caffeic acid significantly inhibited the replication of HCoV-NL63 in a cell-type independent manner, and specifically blocked virus attachment (IC50 = 8.1 µM). Therefore, the results revealed that Sambucus Formosana Nakai stem ethanol extract displayed the strong anti-HCoV-NL63 potential; caffeic acid could be the vital component with anti-HCoV-NL63 activity. The finding could be helpful for developing antivirals against HCoV-NL63.

Extended-Interval Dosing of Rezafungin against Azole-Resistant Aspergillus fumigatus.

We evaluated extended-interval dosing of the investigational echinocandin rezafungin (1, 4, and 16 mg/kg on days 1, 4, and 7 postinoculation) for the treatment of disseminated invasive aspergillosis caused by azole-resistant Aspergillus fumigatus Survival was significantly improved in mice treated with each dose of rezafungin and supratherapeutic posaconazole (20 mg/kg twice daily). Kidney fungal burden, as measured by quantitative real-time PCR, was also significantly reduced in mice treated with rezafungin although variability was observed.

ANTI-VIRAL EFFECT OF HERBAL MEDICINE KOREAN TRADITIONAL CYNANCHUM PANICULATUM (BGE.) KITAG EXTRACTS.

BACKGROUND: Pestiviruses in general, and Bovine Viral Diarrhea (BVD) in particular, present several potential targets for directed antiviral therapy. MATERIAL AND METHODS: The antiviral effect of Cynanchum paniculatum (Bge.) Kitag (Dog strangling vine: DS) extract on the bovine viral diarrhea (BVD) virus was tested. First, a cytotoxicity test in MDBK (Madin-Darby bovine kidney) cells was done with all organic extract concentrations. RESULTS: The cytotoxic concentration CC50 for the ethyl acetate (EA) extracts was 18.2 ug/ml. In the tissue culture, infectious dose (TCID50) assay, the BVD virus decreased when treated with 18.2 ug/ml of the ethyl acetate extracts. CONCLUSION: Ethyl acetate extracts and fractions of the DS extract could be used as a potential antiviral for BVD.

Antiviral effects of black raspberry (Rubus coreanus) seed extract and its polyphenolic compounds on norovirus surrogates.

Black raspberry seeds, a byproduct of wine and juice production, contain large quantities of polyphenolic compounds. The antiviral effects of black raspberry seed extract (RCS) and its fraction with molecular weight less than 1 kDa (RCS-F1) were examined against food-borne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9). The maximal antiviral effect was achieved when RCS or RCS-F1 was added simultaneously to cells with MNV-1 or FCV-F9, reaching complete inhibition at 0.1-1 mg/mL. Transmission electron microscopy (TEM) images showed enlarged viral capsids or disruption (from 35 nm to up to 100 nm) by RCS-F1. Our results thus suggest that RCS-F1 can interfere with the attachment of viral surface protein to host cells. Further, two polyphenolic compounds derived from RCS-F1, cyanidin-3-glucoside (C3G) and gallic acid, identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against the viruses. C3G was suggested to bind to MNV-1 RNA polymerase and to enlarge viral capsids using differential scanning fluorimetry and TEM, respectively.

Detection and quantification of Flavobacterium psychrophilum-specific bacteriophages in vivo in rainbow trout upon oral administration: implications for disease control in aquaculture.

The use of bacteriophages in the treatment and prevention of infections by the fish pathogen Flavobacterium psychrophilum has attracted increased attention in recent years. It has been shown recently that phage delivery via the parenteral route resulted in immediate distribution of phages to the circulatory system and the different organs. However, little is known about phage dispersal and survival in vivo in rainbow trout after delivery via the oral route. Here we examined the dispersal and survival of F. psychrophilum phage FpV-9 in vivo in juvenile rainbow trout after administration by three different methods-bath, oral intubation into the stomach, and phage-coated feed-with special emphasis on the oral route of delivery. Phages could be detected in all the organs investigated (intestine, spleen, brain, and kidney) 0.5 h postadministration, reaching concentrations as high as ∼10(5) PFU mg intestine(-1) and ∼10(3) PFU mg spleen(-1) within the first 24 h following the bath and ∼10(7) PFU mg intestine(-1) and ∼10(4) PFU mg spleen(-1) within the first 24 h following oral intubation. The phages were most persistent in the organs for the first 24 h and then decreased exponentially; no phages were detected after 83 h in the organs investigated. Phage administration via feed resulted in the detection of phages in the intestine, spleen, and kidney 1 h after feeding. Average concentrations of ∼10(4) PFU mg intestine(-1) and ∼10(1) PFU mg spleen(-1) were found throughout the experimental period (200 h) following continuous delivery of phages with feed. These experiments clearly demonstrate the ability of the phages to survive passage through the fish stomach and to penetrate the intestinal barrier and enter the circulatory system after oral delivery, although the quantity of phages found in the spleen was 100- to 1,000-fold lower than that in the intestine. It was also shown that phages could tolerate long periods of desiccation on the feed pellets, with 60% survival after storage at -80°C, and 10% survival after storage at 5°C, for ∼8 months. Continuous delivery of phages via coated feed pellets constitutes a promising method of treatment and especially prevention of rainbow trout fry syndrome.

Expression of antiviral cytokines in Crandell-Reese feline kidney cells pretreated with Korean red ginseng extract or ginsenosides.

The antiviral activity and protective mechanism of Korean red ginseng (KRG) is not well understood. The aim of this study was to investigate the protective mechanism of KRG extract and ginsenosides against feline calicivirus (FCV), a human norovirus surrogate. CRFK cells that were pretreated for 48h with 10µg/mL of KRG extract or purified ginsenoside Rb1 or Rg1, were inoculated with FCV. RNA extracted from each treated group was examined for the expression of antiviral cytokines, including interferon-α (IFN-α), interferon-ß (IFN-ß), interferon-ω (IFN-ω), Mx, and zinc finger antiviral protein shorter isoform (ZAPS), by relative real-time reverse transcription-polymerase chain reaction. mRNA expression of IFN-α, IFN-ß, IFN-ω, Mx, and ZAPS was significantly induced in the FCV-challenged group pretreated with the KRG extract or ginsenosides, and it was higher than the group treated with FCV alone. Mx protein expression was confirmed by western blotting of CRFK cells pretreated with the ginsenoside Rb1 or with Rg1. Induction of antiviral cytokines contributes to the reduction of the viral titer in CRFK cells pretreated with the KRG extract and purified ginsenosides. In future studies, the antiviral protective mechanism of KRG should be demonstrated using other viruses such as human norovirus.

Glutamine modifies immune responses of mice infected with porcine circovirus type 2.

The present study was conducted to evaluate the immune-enhancing effects of dietary L-glutamine supplementation in porcine circovirus type 2 (PCV2)-infected mice, and to examine the clearance effects of glutamine against PCV2 in experimentally infected mice. A total of sixty Kunming female mice were infected with PCV2 at a dose of 100 TCID(50) (50% tissue culture infection dose) by intraperitoneal injection after 2 weeks of dietary L-glutamine supplementation or L-alanine supplementation (as the control (isonitrogenous) group). The measured variables on 3rd, 5th, 7th, 9th and 11th d post-infection (dpi) included: (1) PCV2 virus loaded in the liver, spleen, heart, lung, kidney, ovary and serum was determined by real-time PCR; (2) IL-2, IL-6, IL-10, interferon (IFN)-α, IFN-γ and C-reactive protein levels in serum were measured by ELISA; (3) serum total superoxide dismutase activity was measured spectrophotometrically at 550nm absorbance. Dietary L-glutamine supplementation significantly increased serum IL-2 levels on the 3rd (P<0·01), 5th (P<0·01), 7th (P<0·05) and 9th dpi, significantly (P<0·05) increased serum IL-6 levels on 3rd dpi, significantly (P<0·05) increased serum IFN-g levels on the 9th and 11th dpi and significantly decreased (P<0·01) serum IL-10 levels on the 9th and 11th dpi, compared with those in the control group. Meanwhile, the PCV2 virus genome was detected sporadically throughout the experimental period in both groups. Taken together, the present results suggest that dietary L-glutamine supplementation enhances immune function in PCV2-infected mice.

(-)-Epigallocatechin-3-gallate is a new inhibitor of hepatitis C virus entry.

UNLABELLED: Here, we identify (-)-epigallocatechin-3-gallate (EGCG) as a new inhibitor of hepatitis C virus (HCV) entry. EGCG is a flavonoid present in green tea extract belonging to the subclass of catechins, which has many properties. Particularly, EGCG possesses antiviral activity and impairs cellular lipid metabolism. Because of close links between HCV life cycle and lipid metabolism, we postulated that EGCG may interfere with HCV infection. We demonstrate that a concentration of 50 µM of EGCG inhibits HCV infectivity by more than 90% at an early step of the viral life cycle, most likely the entry step. This inhibition was not observed with other members of the Flaviviridae family tested. The antiviral activity of EGCG on HCV entry was confirmed with pseudoparticles expressing HCV envelope glycoproteins E1 and E2 from six different genotypes. In addition, using binding assays at 4°C, we demonstrate that EGCG prevents attachment of the virus to the cell surface, probably by acting directly on the particle. We also show that EGCG has no effect on viral replication and virion secretion. By inhibiting cell-free virus transmission using agarose or neutralizing antibodies, we show that EGCG inhibits HCV cell-to-cell spread. Finally, by successive inoculation of naïve cells with supernatant of HCV-infected cells in the presence of EGCG, we observed that EGCG leads to undetectable levels of infection after four passages. CONCLUSION: EGCG is a new, interesting anti-HCV molecule that could be used in combination with other direct-acting antivirals. Furthermore, it is a novel tool to further dissect the mechanisms of HCV entry into the hepatocyte.

Vaccine-induced antibodies linked to bovine neonatal pancytopenia (BNP) recognize cattle major histocompatibility complex class I (MHC I).

A mysterious disease affecting calves, named bovine neonatal pancytopenia (BNP), emerged in 2007 in several European countries. Epidemiological studies revealed a connection between BNP and vaccination with an inactivated vaccine against bovine virus diarrhea (BVD). Alloantibodies reacting with blood leukocytes of calves were detected in serum and colostrum of dams, which have given birth to calves affected by BNP. To understand the linkage between vaccination and the development of alloantibodies, we determined the antigens reacting with these alloantibodies. Immunoprecipitation of surface proteins from bovine leukocytes and kidney cells using sera from dams with a confirmed case of BNP in their gestation history reacted with two dominant protein species of 44 and 12 kDa. These proteins were not detected by sera from dams, free of BVDV and not vaccinated against BVD, and from sera of animals vaccinated with a different inactivated BVD vaccine. The 44 kDa protein was identified by mass spectrometry analysis as MHC I, the other as ß-2-microglobulin. The presence of major histocompatibility complex class I (MHC I) in the vaccine was confirmed by Western blot using a MHC I specific monoclonal antibody. A model of BNP pathogenesis is proposed.

Anti-influenza activity of marchantins, macrocyclic bisbibenzyls contained in liverworts.

The H1N1 influenza A virus of swine-origin caused pandemics throughout the world in 2009 and the highly pathogenic H5N1 avian influenza virus has also caused epidemics in Southeast Asia in recent years. The threat of influenza A thus remains a serious global health issue and novel drugs that target these viruses are highly desirable. Influenza A possesses an endonuclease within its RNA polymerase which comprises PA, PB1 and PB2 subunits. To identify potential new anti-influenza compounds in our current study, we screened 33 different types of phytochemicals using a PA endonuclease inhibition assay in vitro and an anti-influenza A virus assay. The marchantins are macrocyclic bisbibenzyls found in liverworts, and plagiochin A and perrottetin F are marchantin-related phytochemicals. We found from our screen that marchantin A, B, E, plagiochin A and perrottetin F inhibit influenza PA endonuclease activity in vitro. These compounds have a 3,4-dihydroxyphenethyl group in common, indicating the importance of this moiety for the inhibition of PA endonuclease. Docking simulations of marchantin E with PA endonuclease suggest a putative "fitting and chelating model" as the mechanism underlying PA endonuclease inhibition. The docking amino acids are well conserved between influenza A and B. In a cultured cell system, marchantin E was further found to inhibit the growth of both H3N2 and H1N1 influenza A viruses, and marchantin A, E and perrotein F showed inhibitory properties towards the growth of influenza B. These marchantins also decreased the viral infectivity titer, with marchantin E showing the strongest activity in this assay. We additionally identified a chemical group that is conserved among different anti-influenza chemicals including marchantins, green tea catechins and dihydroxy phenethylphenylphthalimides. Our present results indicate that marchantins are candidate anti-influenza drugs and demonstrate the utility of the PA endonuclease assay in the screening of phytochemicals for anti-influenza characteristics.

Inhibitory effects of indigowoad root polysaccharides on porcine reproductive and respiratory syndrome virus replication in vitro.

BACKGROUND: Indigowoad root polysaccharide (IRPS) is a natural polysaccharide isolated from the traditional Chinese medicinal herb Radix Isatidis, and has many kinds of biological activities. However, the IRPS antiviral activity, especially the anti-porcine reproductive and respiratory syndrome virus (PRRSV) effect, has not been evaluated. METHODS: PRRSV was propagated in the MARC-145 cell line, and viral titre was determined by cytopathic effect and expressed as the 50% tissue culture infection dose (TCID(50)) in the current study. The cell cytotoxic effect of IRPS toward MARC-145 was evaluated by MTT assay firstly, then the inhibitory effects of IRPS on PRRSV replication in vitro were investigated by determining the effect of IRPS upon a single replicative cycle of PRRSV in MARC-145 cells. The effects of IRPS on viral RNA and protein synthesis in PRRSV-infected cells were investigated using real-time PCR and double-antibody (sandwich) ELISA. RESULTS: IRPS was able to effectively suppress the infectivity of the PRRSV in a dose-dependent manner, especially by adding IRPS during the PRRSV infection. IRPS could affect the attachment of PRRSV to MARC-145 cells, and also inhibit the viral RNA and protein synthesis. CONCLUSIONS: IRPS has an antiviral effect on PRRSV replication in MARC-145 cells and might be useful in medical development for antiviral research. However, the precise mechanism of the host and viral targets of IRPS are unknown, so further studies should be conducted to investigate the precise mechanism of IRPS inhibitory effect on PRRSV infection.

Forsythoside a inhibits the avian infectious bronchitis virus in cell culture.

Forsythoside A is a polyphenolic constituent of the fruits of Forsythia suspensa Vahl. which is widely used as an antiinflammatory agent in traditional Chinese medicine. In the present study, the effects of forsythoside A on cell infection by avian infectious bronchitis virus were assessed. A real-time fluorescence quantitative PCR assay was used to determine mRNA content of IBV N gene. The pretreatment of cells with forsythoside A, adding forsythoside A post infection of cells, and treatment of virus with forsythoside A were analysed. The inhibitory effect of forsythoside A was confirmed by infecting primary chicken embryo kidney cells. Infected cells were inhibited by forsythoside A treatment. The data indicated that forsythoside A has the potential to prevent IBV infection in vitro. Copyright © 2010 John Wiley & Sons, Ltd.

[Biological evaluation of Radix Isatidis based on neuraminidase activity assay].

Radix Isatidis (Banlangen in Chinese) is a traditional Chinese medicinal (TCM) herb, and is frequently used for treating influenza. However, the current quality control method for Radix Isatidis should be developed since it has little correlation to the pharmacodynamic action. In this paper, the in vitro inhibitory action of Radix Isatidis on neuraminidase (NA) was investigated by fluorometric assay with 4-methylumbelliferyl-D-N-acetylneuraminate (FL-MU-NANA) method. Based on the method, the experimental condition was optimized and a bioassay statistic method was established according to the reaction type and the regularity of "parallel lines of qualitative effect". Then the bioassay method of Radix Isatidis was established. This study indicated that Radix Isatidis had obvious in vitro inhibitory activity on NA with IC50 = (0.90 +/- 0.20) mg x mL(-1) (herb). The correlation between logarithmic dose and reaction rate showed an "S" shape--is quite similar to Tamiflu's reaction curve, which hinted that Radix Isatidis had the same inhibitory function on NA as Tamiflu. The established bioassay method of "parallel lines of qualitative effect" had a good reproducibility (RSD = 5.78%). The results of potency determination of Radix Isatidis were reliable (reliability test: deviation from straight line P > 0.05, deviation from parallel line P > 0.05) and well regular. As a conclusion, this bioassay method is suitable to control and evaluate the quality of Radix Isatidis.

Establishment of murine cytomegalovirus latency in vivo is associated with changes in histone modifications and recruitment of transcriptional repressors to the major immediate-early promoter.

Human cytomegalovirus (CMV) is a ubiquitous herpesvirus with the ability to establish a lifelong latent infection. The mechanism by which this occurs is not well understood. Regulation of, for example, immediate-early (IE) gene expression is thought to be a critical control point in transcriptional control of the switch between latency and reactivation. Here, we present evidence that supports previous studies showing that the majority of genomes are quiescent with respect to gene expression. To study the possible role of epigenetic factors that may be involved in repression of ie gene expression in latency, we have analyzed changes in the patterns of modifications of histones bound to the major IE promoter (MIEP) in the kidneys of acutely and latently infected mice. Our studies show that, like herpes simplex virus, murine CMV genomes become relatively enriched in histones in latent infection. There are dramatic changes in modifications of histones associated with the MIEP when latency is established: H3 and H4 become hypoacetylated and H3 is hypomethylated at lysine 4, while H3 lysine 9 is hypermethylated in latently infected mice. These changes are accompanied by a relative loss of RNA polymerase and gain of heterochromatin protein 1gamma and Yin-Yang 1 bound to the MIEP. Our studies suggest that, in the majority of cells, CMV establishes a true latent infection, defined as the lack of expression of genes associated with productive infection, and that this occurs through changes in histone modifications and recruitment of transcriptional silencing factors to the MIEP.

Efficacy of orally administered Lobelia chinensis extracts on herpes simplex virus type 1 infection in BALB/c mice.

By a plaque reduction assay, methanolic extracts from Lobelia chinensis (LC) significantly blocked herpes simplex virus type 1 (HSV-1) replication in HeLa cells without apparent cytotoxicity. The 50% inhibitory concentration (IC(50)) of LC on HSV-1 replication is 139.2 microg/ml. To elucidate LC anti-HSV-1 activity in vivo, BALB/c mice were injected subcutaneously with HSV-1 (2.5 x 10(6)PFU/50 microl), treated orally thrice a day with acyclovir (60 mg/kg/dose) or LC (20 and 50 mg/kg/dose) for 7 days, and inspected daily for signs of disease. Data from the scoring system indicated that animals infected with HSV-1, developed progressive zoster lesions starting 2 days postinfection (p.i.) and appeared the most serious syndromes at 4-5 days p.i. In marked contrast to the results with control mice, treatment with acyclovir or 50 mg/kg/dose LC resulted in a sustained protective effect. The HSV-1 titers and DNA levels in ground skin samples were significantly reduced by LC. No toxic effect of LC on liver and kidney functions was apparent. These results indicated that LC was a potent inhibitor of the in vitro and in vivo replication of HSV-1.

Anti-influenza virus activity of Chaenomeles sinensis.

AIM OF THE STUDY: This investigation evaluated anti-influenza virus activity of 50% ethanol extract of the fruit of Chaenomeles sinensis K(OEHNE), which is widely used as a traditional Chinese medicine to treat throat diseases. MATERIAL AND METHODS: Type A and B influenza viruses were treated with the extract at various concentrations for 1h at room temperature; then the plaque titers of the treated viruses were determined. The neutralizing component in the extract was partially purified using HP20 column chromatography. RESULTS: Treatment with the extract at concentrations greater than 5mg/ml reduced the plaque titers of the both viruses to less than 10% of those of untreated viruses. The treatment inhibited viral hemagglutination activity, too. When the 50mg/ml extract was added to the culture medium after inoculation of the virus, viral NS2 protein synthesis was selectively inhibited and progeny virus was not detected in the infected cell medium. Partial purification showed that the neutralizing component consisted of high molecular weight polyphenols. CONCLUSION: High molecular weight polyphenols in the fruits of C. sinensis neutralizes influenza virus by inhibiting hemagglutination activity and by suppressing NS2 protein synthesis.

The in vitro activity of geraniin and 1,3,4,6-tetra-O-galloyl-beta-D-glucose isolated from Phyllanthus urinaria against herpes simplex virus type 1 and type 2 infection.

Phyllanthus urinaria Linnea (Euphorbiaceae) is a widely used traditional medicinal plant by oriental countries and has been reported to possess various biological activities. Previously, the acetone extract from Phyllanthus urinaria was found to inhibit herpes simplex virus (HSV) infection. In this study, geraniin and 1,3,4,6-tetra-O-galloyl-beta-D-glucose (1346TOGDG), both of which were isolated from the acetone extract of Phyllanthus urinaria, were examined for their activity against HSV-1 and HSV-2 in vitro. Results showed that geraniin actively suppressed HSV-2 infection, whereas 1346TOGDG effectively inhibited HSV-1 infection. The 50% inhibitory concentration (IC(50)) was 18.4+/-2.0 microM for geraniin against HSV-2 infection, and 19.2+/-4.0 microM for 1346TOGDG against HSV-1. No toxic effect towards the host cell was observed at the antiviral concentrations. In conclusion, geraniin and 1346TOGDG were found to inhibit HSV-1 and HSV-2 multiplication at different magnitudes of potency.

Detailed design and comparative analysis of protocols for optimized production of high-performance HIV-1-derived lentiviral particles.

Transgenic HIV-1-derived lentiviral particles are at the forefront of current gene therapy and tissue engineering initiatives, which will require optimal protocols for large-scale production of clinical-grade therapeutic lentiviruses. Production of latest-generation self-inactivating lentiviral particles requires cotransfection of mammalian production cell lines with two helper plasmids along with the lentivector, whose transgene-encoding expression cassette is the only genetic information stably transduced into target chromosomes. Capitalizing on a recently designed lentiviral expression vector family, we conducted rigorous analysis of production-relevant parameters including transfection, cell density, media composition, temperature, relative (helper) vector concentrations and genetic configuration. Comparative analysis of lentiviral particle performance (VP) was based on the viral titer (reflecting the number of transduction-competent lentiviral particles) relative to the number of lentiviral particles produced (correlating with p24 production levels) (VP=titer/viral particle number). Optimal lentiviral production parameters, resulting in up to 132-fold greater VP compared to standard protocols, required (i) CaPO4-based transfection (ii) of helper plasmids and lentivector at a fixed concentration ratio (helper plasmid I:helper plasmid II:lentivector=1:1:2) (iii) into 1x10(5) human embryonic kidney cells/cm2 (HEK293-T) (iv) cultivated at 37 degrees C (v) in Advanced D-MEM medium supplemented with (vi) 2% fetal calf serum, (vii) and a culture additive containing 0.01 mM cholesterol, 0.01 mM egg's lecithin and 1x chemically defined lipid concentrate. (viii) Furthermore, constitutive transgene expression units placed in a forward polyadenylation site (pA)-free orientation relative to the lentivector backbone resulted in optimal transgene transduction/expression. Our studies suggest that detailed knowledge of lentivector design and the production of lentiviral particles will advance large-scale manufacturing of clinically relevant lentiviruses for future gene therapy applications.

Antiviral activity in vitro of Urtica dioica L., Parietaria diffusa M. et K. and Sambucus nigra L.

Parietaria diffusa M. et K., Urtica dioica L. (Urticaceae) and Sambucus nigra L. (Caprifoliaceae) are plants usually used in popular medicine of central Italy for treating numerous diseases, first of all Herpes zoster. Several plant products have been described as potential antiviral agents, with special attention being devoted to those having retroviruses as etiological agents, including acquired immunodeficiency syndrome (AIDS), in which a retrovirus, the designated human immunodeficiency virus HIV, has been clearly identified as the primary cause of this disease. The present study proposes a preliminary screening of the antiviral activity of Parietaria diffusa, Sambucus nigra and Urtica dioica preparation against the feline immunodeficiency virus (FIV) infection. The feline immunodeficiency virus is a widespread lentivirus of domestic cats sharing numerous biological and pathogenic features with the human immunodeficiency virus (HIV). FIV infection in cats has therefore been proposed as an animal model for AIDS studies with respect to pathogenesis, chemotherapy, and vaccine development [Pedersen, N.C., 1993. Feline immunodeficiency virus infection. In: Levy, J.A. (Ed.), The Retroviridae. Plenum Press, New York; Bendinelli, M., Pistello, M., Lombardi, S., Poli, A., Garzelli, C., Matteucci, D., Ceccherini-Nelli, L., Malvaldi, G., Tozzini, F., 1995. Feline immunodeficiency virus: an interesting model for AIDS studies and an important cat pathogen. Clinical Microbiology Revue 8, 87-112; North, T.W., LaCasse, R.A., 1995. Testing anti-HIV drugs in the FIV model. Nature Medicine 1, 410-411; Matteucci, D., Pistello, M., Mazzetti, P., Giannechini, S., Isola, P., Merico, A., Zaccaro, L., Rizzati, A., Bendinelli, M., 2000. AIDS vaccination studies using feline immunodeficiency virus as a model: immunisation with inactivated whole virus suppresses viraemia levels following intravaginal challenge with infected cells but non-following intravenous challenge with cell-free virus. Vaccine 18, 119-130]. Early studies showed that some of them presented antiviral activity against infection of FIV as assayed by syncytia formation using feline kidney Crandell cells (CrFK).