Evaluation of Anti-amoebic Activity of Spring Leaf Extract of Artemisia aucheri on Acanthamoeba (T4 strain) In vitro.

2020 ◽  
Vol 18 ◽  
Author(s):  
Amir Karimi Pour Saryazdi ◽  
Yeganeh Karimi Pour Saryazdi ◽  
Fatemeh Ghaffarifar ◽  
Maryam Ahmadi ◽  
Leila Zaki
Keyword(s):  
Flow Cytometry ◽  
Drug Candidate ◽  
Free Living ◽  
Macrophage Cells ◽  
Ic50 Value ◽  
Artemisia Aucheri ◽  
Protozoan Infections ◽  
Reverse Relationship ◽  
Spring Leaf

Background: Acanthamoeba belongs to the free-living amoebae genus that caused a widespread infection with different severity in humans and animals. Treatment of these opportunistic protozoan infections is not still safe or effective. The aim of the present study was to evaluate the effect of spring extract of Artemisia aucheri on Acanthamoeba in vitro. Method: Trophozoites and cysts of Acanthamoeba cultured on non-nutrient agar plates containing bacteria Escherichia coli. Macrophage cells were cultured in RPMI-1640 medium. Different concentrations of spring extract of A. aucheri were added to cultivated parasites and macrophages and additionally calculated to determine the 50% inhibitory concentration (IC50) for parasites and its 50% cytotoxic concentration (CC50) for macrophages. Then, the viability of parasites was evaluated using counting assay. MTT assay was carried out on macrophage cells based on growth inhibition. Furthermore, in order to determine the possible induction of apoptosis in cysts of Acanthamoeba, flow cytometry method was employed using annexin staining. Results: The effect of A. aucheri on trophozoites and cysts of Acanthamoeba was effective and has a reverse relationship with its concentration. The IC50 value of spring extract on trophozoites and cysts of parasite was estimated 200 and 333 μg/ml at 24 h, respectively. According to the results of flow cytometry, the spring A. aucheri extract caused about 20% apoptosis. Conclusion: Regarding the above results, it can be concluded that spring A. aucheri extract was effective against trophozoite and cyst forms of Acanthamoeba in vitro. Therefore, this plant could be a herbal drug candidate appropriate for treatment of Acanthamoeba infections.

scholarly journals 228 Antagonistic pH-selective VISTA antibody SNS-101 potentiates anti-PD-1/PD-L1-induced anti-tumor immunity

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A243-A243
Author(s):  
Thomas Thisted ◽  
Arnab Mukherjee ◽  
Kanam Malhotra ◽  
Zuzana Biesova ◽  
Yuliya Kleschenko ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
T Cell ◽  
T Cell Activation ◽  
Drug Disposition ◽  
Checkpoint Inhibitors ◽  
Tumor Rejection ◽  
Therapeutic Window ◽  
Drug Candidate

BackgroundImmunotherapies, especially immune checkpoint inhibitors, have become a cornerstone of cancer treatment. Remarkable clinical responses have been observed blocking the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) axis across a spectrum of indications. However, innate and/or acquired resistance to anti-PD-1 blockade remains a major challenge. V-domain Ig suppressor of T-cell activation (VISTA) is a B7-family member, which promotes T-cell and myeloid quiescence and represents a promising target, particularly in combination with anti-PD-1/PD-L1 treatment. Recently, the interaction of VISTA with its receptor PSGL-1 was demonstrated to be significantly enhanced by the acidic tumor microenvironment (TME). As VISTA is highly expressed on myeloid cells, including those in the blood, antibodies binding VISTA at physiological pH 7.4 could result in rapid elimination from circulation through targeted-mediated drug disposition, making efficacious drug occupancy levels difficult to reach and potentially narrowing the therapeutic window. An antibody engineered to selectively bind and block VISTA at low pH in the TME may therefore be an ideal drug candidate.MethodsIn this study, fully human anti-VISTA antibodies were generated through pH-selective enrichment strategies of a yeast-based display library comprising highly diverse synthetic immune repertoires. The ‘parental’ antibodies have been extensively characterized using in vitro flow-cytometry, surface-plasmon resonance (SPR) and PSGL-1/VISTA inhibition assays in primary human CD4 and CD8 T-cells at pH 6.0 and pH 7.4. Eight parental antibodies were identified and tested for combinatorial efficacy with anti-PD-1 in vivo in human VISTA knock-in mice inoculated with syngeneic MC-38 tumors. These antibodies underwent further optimization for enhanced binding affinity at pH 6.0 and decreased binding at pH 7.4. ‘Progeny’ antibody ranking was based on the same in vitro and in vivo characterization as parental antibodies.ResultsEighty four parental antibodies were initially discovered. Flow-cytometry and SPR analysis revealed candidates displaying pH-dependent binding to endogenously expressed native VISTA on cells, and a PSGL-1/VISTA inhibition assay at pH 6.0 was run to identify and rank potent interface blockers. Eight candidate antibodies were tested in an in vivo intervention study in combination with anti-murine PD-1 demonstrating varied combinatorial efficacy with a subset leading to superior tumor rejection. Characterization of optimized progeny antibodies led to identification of anti-VISTA antibody SNS-101.ConclusionsEnrichment of highly diverse antibody libraries led to the identification of a pH-selective inhibitory anti-VISTA antibody SNS-101, which exerts excellent combinability with anti-PD-1 leading to superior anti-tumor activity in a mouse model.

scholarly journals Isolation, Characterization and Antitumor Effect on DU145 Cells of a Main Polysaccharide in Pollen of Chinese Wolfberry

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2430 ◽  
Author(s):  
Fei Chen ◽  
Linwu Ran ◽  
Jia Mi ◽  
Yamei Yan ◽  
Lu Lu ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Deae Cellulose ◽  
Tunel Assay ◽  
Hot Water ◽  
Molar Ratio ◽  
Antitumor Effects ◽  
Flow Cytometry Assay ◽  
Ic50 Value ◽  
Dose Dependent

Modern studies have shown that pollen has a certain role in the treatment of prostate-related diseases. In the present study, pollen polysaccharides from Chinese wolfberry (WPPs) were extracted by hot-water extraction and ethanol precipitation, further purified by chromatography on a DEAE-cellulose column and Sephadex G-100 column. Homogeneous polysaccharide CF1 of WPPS was obtained, the molecular weight of which was estimated to be 1540.10 ± 48.78 kDa by HPGPC-ELSD. HPLC with PMP derivatization analysis indicated that the monosaccharide compositions of CF1 were mannose, glucuronic acid, galacturonic acid, xylose, galactose, arabinose, and trehalose, in a molar ratio of 0.68:0.59:0.27:0.24:0.22:0.67:0.08. The antitumor effects of CF1 upon MTT, Tunel assay and flow cytometry assay were investigated in vitro. The results showed that CF1 exhibited a dose-dependent antiproliferative effect, with an IC50 value of 374.11 μg/mL against DU145 prostate cancer cells. Tunel assay and flow cytometry assay showed that the antitumor activity of CF1 was related to apoptosis in vitro. The present study suggested that the CF1 of WPPs might be a potential source of antitumor functional food or agent.

Comparison the effects of Sambucus ebulus leaf and fruit extracts on Leishmania major in-vitro

2019 ◽  
Vol 20 ◽  
Author(s):  
Samira Kadkhodamasoum ◽  
Farahnaz Bineshian ◽  
Amir KarimiPour ◽  
Pooya Tavakoli ◽  
Masoud Foroutan ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Leaf Extract ◽  
Leishmania Major ◽  
Drug Candidate ◽  
Fruit Extract ◽  
Fruit Extracts ◽  
Sambucus Ebulus ◽  
Apoptotic Effect ◽  
Ic50 Concentration

Background;: Leishmaniasis is one of the major diseases caused by the intracellular parasite of Leishmania. It has become one of the most dangerous health problems today. Our aim of the present study is to compare the effects of Sambucus ebulus leaf and fruit extracts on Leishmania major in vitro. Methods: In this study, we used MTT, promastigote and amastigote assay to evaluate the effect of different concentrations of the extract on parasite and we compared their effects. The flow cytometry technique was also used to detect the apoptotic effect of the extracts on promastigotes. Results: According to MTT experiment IC50 concentration of leaf and fruit extracts on parasite was 157 μg/ml and 265 μg/ml, respectively. After analysis by flow cytometry, leaf and fruit extracts also showed apoptosis effect. Leaf and fruit extract caused 40.2 and 2.67 percent apoptosis. Conclusion: Based on the above assessment, we determined that the S. ebulus leaf extract has a more toxic effect on promastigotes and amstigotes than its fruit extract and maybe in the future that be used as a drug candidate.

A Simple and Rapid Method to Determine GPIIb/IIIa-Receptor Inhibitor Activity in Whole Blood

1999 ◽  
Vol 19 (03) ◽  
pp. 134-138
Author(s):  
Gitta Kühnel ◽  
A. C. Matzdorff
Keyword(s):  
Flow Cytometry ◽  
Platelet Count ◽  
Blood Sample ◽  
Platelet Activation ◽  
Whole Blood ◽  
Receptor Occupancy ◽  
Aggregate Formation ◽  
Inhibitor Activity ◽  
Receptor Inhibitor

SummaryWe studied the effect of GPIIb/IIIa-inhibitors on platelet activation with flow cytometry in vitro. Citrated whole blood was incubated with increasing concentrations of three different GPIIb/IIIa-inhibitors (c7E3, DMP728, XJ757), then thrombin or ADP were added and after 1 min the sample was fixed. Samples without c7E3 but with 0.1 U/ml thrombin had a decrease in platelet count. Samples with increasing concentrations of c7E3 had a lesser or no decrease in platelet count. The two other inhibitors (DMP 725, XJ757) gave similar results. GPIIb/IIIa-inhibitors prevent aggregate formation and more single platelets remain in the blood sample. The agonist-induced decrease in platelet count correlates closely with the concentration of the GPIIb/IIIa inhibitor and receptor occupancy. This correlation may be used as a simple measure for inhibitor activity in whole blood.

Are Carbonic Anhydrases Suitable Targets to Fight Protozoan Parasitic Diseases?

2019 ◽  
Vol 25 (39) ◽  
pp. 5266-5278 ◽  
Author(s):  
Katia D'Ambrosio ◽  
Claudiu T. Supuran ◽  
Giuseppina De Simone
Keyword(s):  
Drug Resistance ◽  
Animal Models ◽  
Carbonic Anhydrase ◽  
Drug Target ◽  
Treatment Options ◽  
Parasitic Diseases ◽  
Carbonic Anhydrases ◽  
Extensive Drug Resistance ◽  
Protozoan Infections

Protozoans belonging to Plasmodium, Leishmania and Trypanosoma genera provoke widespread parasitic diseases with few treatment options and many of the clinically used drugs experiencing an extensive drug resistance phenomenon. In the last several years, the metalloenzyme Carbonic Anhydrase (CA, EC 4.2.1.1) was cloned and characterized in the genome of these protozoa, with the aim to search for a new drug target for fighting malaria, leishmaniasis and Chagas disease. P. falciparum encodes for a CA (PfCA) belonging to a novel genetic family, the η-CA class, L. donovani chagasi for a β-CA (LdcCA), whereas T. cruzi genome contains an α-CA (TcCA). These three enzymes were characterized in detail and a number of in vitro potent and selective inhibitors belonging to the sulfonamide, thiol, dithiocarbamate and hydroxamate classes were discovered. Some of these inhibitors were also effective in cell cultures and animal models of protozoan infections, making them of considerable interest for the development of new antiprotozoan drugs with a novel mechanism of action.

Tamarix articulata (T. articulata) - An Important Halophytic Medicinal Plant with Potential Pharmacological Properties

2019 ◽  
Vol 20 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Abdullah M. Alnuqaydan ◽  
Bilal Rah
Keyword(s):  
Medicinal Plant ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Biological Properties ◽  
In Vivo Model ◽  
Drug Candidate ◽  
Phytochemical Analysis ◽  
Pharmacological Properties

Background:Tamarix Articulata (T. articulata), commonly known as Tamarisk or Athal in Arabic region, belongs to the Tamaricaece species. It is an important halophytic medicinal plant and a good source of polyphenolic phytochemical(s). In traditional medicines, T. articulata extract is commonly used, either singly or in combination with other plant extracts against different ailments since ancient times.Methods:Electronic database survey via Pubmed, Google Scholar, Researchgate, Scopus and Science Direct were used to review the scientific inputs until October 2018, by searching appropriate keywords. Literature related to pharmacological activities of T. articulata, Tamarix species, phytochemical analysis of T. articulata, biological activities of T. articulata extracts. All of these terms were used to search the scientific literature associated with T. articulata; the dosage of extract, route of administration, extract type, and in-vitro and in-vivo model.Results:Numerous reports revealed that T. articulata contains a wide spectrum of phytochemical(s), which enables it to have a wide window of biological properties. Owing to the presence of high content of phytochemical compounds like polyphenolics and flavonoids, T. articulata is a potential source of antioxidant, anti-inflammatory and antiproliferative properties. In view of these pharmacological properties, T. articulata could be a potential drug candidate to treat various clinical conditions including cancer in the near future.Conclusion:In this review, the spectrum of phytochemical(s) has been summarized for their pharmacological properties and the mechanisms of action, and the possible potential therapeutic applications of this plant against various diseases discussed.

Synthesis of a Novel Curcumin Derivative as a Potential Imaging Probe in Alzheimer’s Disease Imaging

2019 ◽  
Vol 16 (8) ◽  
pp. 723-731 ◽  
Author(s):  
Alexander Sturzu ◽  
Sumbla Sheikh ◽  
Hubert Kalbacher ◽  
Thomas Nägele ◽  
Christopher Weidenmaier ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Flow Cytometry ◽  
Transgenic Mice ◽  
Ex Vivo ◽  
Amyloid Plaques ◽  
Laser Scanning Microscopy ◽  
Β Amyloid ◽  
Curcumin Derivative

Background: Curcumin has been of interest in the field of Alzheimer’s disease. Early studies on transgenic mice showed promising results in the reduction of amyloid plaques.However, curcumin is very poorly soluble in aqueous solutions and not easily accessible to coupling as it contains only phenolic groups as potential coupling sites. For these reasons only few imaging studies using curcumin bound as an ester were performed and curcumin is mainly used as nutritional supplement. Methods: In the present study we produced an aminoethyl ether derivative of curcumin using a nucleophilic substitution reaction. This is a small modification and should not impact the properties of curcumin while introducing an easily accessible reactive amino group. This novel compound could be used to couple curcumin to other molecules using the standard methods of peptide synthesis. We studied the aminoethyl-curcumin compound and a tripeptide carrying this aminoethyl-curcumin and the fluorescent dye fluorescein (FITC-curcumin) in vitro on cell culture using confocal laser scanning microscopy and flow cytometry. Then these two substances were tested ex vivo on brain sections prepared from transgenic mice depicting Alzheimer-like β-amyloid plaques. Results: In the in vitro CLSM microscopy and flow cytometry experiments we found dot-like unspecific uptake and only slight cytotoxicity correlating with this uptake. As these measurements were optimized for the use of fluorescein as dye we found that the curcumin at 488nm fluorescence excitation was not strong enough to use it as a fluorescence marker in these applications. In the ex vivo sections CLSM experiments both the aminoethyl-curcumin and the FITC-curcumin peptide bound specifically to β- amyloid plaques. Conclusion: In conclusion we successfully produced a novel curcumin derivative which could easily be coupled to other imaging or therapeutic molecules as a sensor for amyloid plaques.

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