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Anders Johansson - One of the best experts on this subject based on the ideXlab platform.

Scott C. Kachlany - One of the best experts on this subject based on the ideXlab platform.

  • Aggregatibacter Actinomycetemcomitans leukotoxin ltxa leukothera mechanisms of action and therapeutic applications
    Toxins, 2019
    Co-Authors: Scott C. Kachlany, Brian A Vega, Benjamin A Belinka
    Abstract:

    Aggregatibacter Actinomycetemcomitans is an oral pathogen that produces the RTX toxin, leukotoxin (LtxA; Leukothera®). A. Actinomycetemcomitans is strongly associated with the development of localized aggressive periodontitis. LtxA acts as a virulence factor for A. Actinomycetemcomitans to subvert the host immune response by binding to the β2 integrin lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18) on white blood cells (WBCs), causing cell death. In this paper, we reviewed the state of knowledge on LtxA interaction with WBCs and the subsequent mechanisms of induced cell death. Finally, we touched on the potential therapeutic applications of LtxA (trade name Leukothera®) toxin therapy for the treatment of hematological malignancies and immune-mediated diseases.

  • effects of Aggregatibacter Actinomycetemcomitans leukotoxin on endothelial cells
    Microbial Pathogenesis, 2013
    Co-Authors: Anelia Dietmann, Scott C. Kachlany, Alban Millonig, Valery Combes, Pierreolivier Couraud, Georges E Grau
    Abstract:

    Aggregatibacter Actinomycetemcomitans is a human pathogen that produces leukotoxin (LtxA) as a major virulence factor. In this study the effect of LtxA on microvascular endothelial cell viability and phenotype was studied. High doses of single LtxA treatment (500 ng/ml to 5 μg/ml) significantly and irreversibly decreased cell proliferation and induced apoptosis, as assessed by tetrazolium salt and annexin V assay, respectively. Apoptosis was partially inhibited by the pan-caspase inhibitor, z-VAD-fmk. LtxA caused a cell cycle arrest in the G2/M phase after 72 h. Between 500 ng/ml and 5 μg/ml, after long- or short-term stimulation LtxA increased the expression of ICAM-1 and VCAM-1, as well as the percentages of endothelial cells expressing these adhesion molecules. Thus, A. Actinomycetemcomitans LtxA has substantial pro-inflammatory effects on human brain endothelial cells by upregulation of ICAM-1 and VCAM-1. Furthermore, LtxA in higher concentration was found to decrease proliferation and induces apoptosis in microvascular endothelial cells.

  • Aggregatibacter Actinomycetemcomitans Leukotoxin from Threat to Therapy
    Journal of Dental Research, 2010
    Co-Authors: Scott C. Kachlany
    Abstract:

    Aggregatibacter Actinomycetemcomitans is a Gram-negative bacterium that colonizes the human oral cavity and is the causative agent for localized aggressive periodontitis (LAP), an aggressive form of periodontal disease that occurs in adolescents. A. Actinomycetemcomitans secretes a protein toxin, leukotoxin (LtxA), which helps the bacterium evade the host immune response during infection. LtxA is a membrane-active toxin that specifically targets white blood cells (WBCs). In this review, we discuss recent developments in this field, including the identification and characterization of genes and proteins involved in secretion, regulation of LtxA, biosynthesis, newly described activities of LtxA, and how LtxA may be used as a therapy for the treatment of diseases.

Marchella Hendrayanti W - One of the best experts on this subject based on the ideXlab platform.

  • Paparan zat besi pada ekspresi protein spesifik extracellular polymeric substance biofilm Aggregatibacter Actinomycetemcomitans
    Dental Journal: Majalah Kedokteran Gigi, 2014
    Co-Authors: Marchella Hendrayanti W, Indah Listiana K
    Abstract:

    Background: The study of biofilms bacteria could be an alternative of preventive treatment in reducing prevalence of aggressive periodontitis in the community, because biofilm protects the bacteria from environmental conditions, including the attack of immune system and antimicrobial. Aggregatibacter Actinomycetemcomitans is a major cause of bacterial aggressive periodontitis. Purpose: This study aims to examine the iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm. Methods: Protein containing EPS biofilm was isolated from cultures of A.Actinomycetemcomitans. The protein was processed through several procedures: electrophoresis , electroelution , immunization of rabbits , serum isolation , and purification of antibodies. After the Western blotting procedure the antibody was used. Protein containing EPS biofilms exposed to iron, then once again isolated from cultures of A. Actinomycetemcomitans. The electrophoresis and Western blotting were done on the isolated protein. Results: The result showed that the the expression of specific proteins in EPS biofilm decreased in response to iron exposure. Conclusions: Iron exposure could influenced the specific protein expression in EPS biofilm of Aggregatibacter Actinomycetemcomitans. Latar belakang: Penelitian terhadap bakteri biofilm dapat menjadi alternatif perawatan preventif dalam menurunkan prevalensi periodontitis agresif di masyarakat, karena biofilm melindungi bakteri terhadap kondisi lingkungan, termasuk serangan sistem imun dan antimikroba. Aggregatibacter Actinomycetemcomitans merupakan bakteri penyebab utama periodontitis agresif. Tujuan: Studi ini bertujuan meneliti paparan zat besi terhadap ekspresi protein spesifik extracellular polymeric substance (EPS) Aggregatibacter Actinomycetemcomitans. Metode: Protein yang mengandung EPS biofilm diisolasi dari kultur A. Actinomycetemcomitans. Protein yang diisolasi ini kemudian melalui beberapa prosedur: elektroforesis, elektroelusi, imunisasi pada kelinci, isolasi serum, dan purifikasi antibodi. Pada prosedur Western blotting di sesi penelitian berikutnya antibodi ini digunakan. Protein yang mengandung EPS biofilm dipapar dengan zat besi, kemudian diisolasi sekali lagi dari kultur A. Actinomycetemcomitans. Protein yang diisolasi dilakukan elektroforesis dan Western blotting. Western blotting. Hasil: Penelitian ini menunjukkan hasil berupa penurunan ekspresi protein spesifik biofilm EPS sebagai respon terhadap paparan zat besi. Simpulan: Paparan zat besi memberi pengaruh ekspresi protein spesifik biofilm EPS Aggregatibacter Actinomycetemcomitans.

  • Iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm
    Dental Journal: Majalah Kedokteran Gigi, 2014
    Co-Authors: Marchella Hendrayanti W, Indah Listiana Kriswandini
    Abstract:

    Background The study of biofilms bacteria could be an alternative of preventive treatment in reducing prevalence of aggressive periodontitis in the community, because biofilm protects the bacteria from environmental conditions, including the attack of immune system and antimicrobial. Aggregatibacter Actinomycetemcomitans is a major cause of bacterial aggressive periodontitis. Purpose This study aims to examine the iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm. Methods Protein containing EPS biofilm was isolated from cultures of A.Actinomycetemcomitans. The protein was processed through several procedures electrophoresis , electroelution , immunization of rabbits , serum isolation, and purification of antibodies. After the Western blotting procedure the antibody was used. Protein containing EPS biofilms exposed to iron, then once again isolated from cultures of A. Actinomycetemcomitans. The electrophoresis and Western blotting were done on the isolated protein. Results The result showed that the the expression of specific proteins in EPS biofilm decreased in response to iron exposure. Conclusions Iron exposure could influenced the specific protein expression in EPS biofilm of Aggregatibacter Actinomycetemcomitans.

  • Iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm Paparan zat besi pada ekspresi protein spesifik extracellular polymeric substance (EPS) biofilm Aggregatibacter a
    2014
    Co-Authors: Marchella Hendrayanti W, Mahasiswa Fakultas Kedokteran Gigi, Dosen Fakultas Kedokteran Gigi
    Abstract:

    Background: The study of biofilms bacteria could be an alternative of preventive treatment in reducing prevalence of aggressive periodontitis in the community, because biofilm protects the bacteria from environmental conditions, including the attack of immune system and antimicrobial. Aggregatibacter Actinomycetemcomitans is a major cause of bacterial aggressive periodontitis. Purpose: This study aims to examine the iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm. Methods: Protein containing EPS biofilm was isolated from cultures of A.actinomycet emcomitans. The protein was processed through several procedures: electrophoresis , electroelution , immunization of rabbits , serum isolation, and purification of antibodies. After the Western blotting procedure the antibody was used. Protein containing EPS biofilms exposed to iron, then once again isolated from cultures of A. Actinomycetemcomitans. The electrophoresis and Western blotting were done on the isolated protein. Results: The result showed that the the expression of specific proteins in EPS biofilm decreased in response to iron exposure. Conclusions: Iron exposure could influenced the specific protein expression in EPS biofilm of Aggregatibacter Actinomycetemcomitans.

Pirkko J. Pussinen - One of the best experts on this subject based on the ideXlab platform.

Indah Listiana Kriswandini - One of the best experts on this subject based on the ideXlab platform.

  • Iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm
    Dental Journal: Majalah Kedokteran Gigi, 2014
    Co-Authors: Marchella Hendrayanti W, Indah Listiana Kriswandini
    Abstract:

    Background The study of biofilms bacteria could be an alternative of preventive treatment in reducing prevalence of aggressive periodontitis in the community, because biofilm protects the bacteria from environmental conditions, including the attack of immune system and antimicrobial. Aggregatibacter Actinomycetemcomitans is a major cause of bacterial aggressive periodontitis. Purpose This study aims to examine the iron exposure to specific protein expression of extracellular polymeric substance (EPS) of Aggregatibacter Actinomycetemcomitans biofilm. Methods Protein containing EPS biofilm was isolated from cultures of A.Actinomycetemcomitans. The protein was processed through several procedures electrophoresis , electroelution , immunization of rabbits , serum isolation, and purification of antibodies. After the Western blotting procedure the antibody was used. Protein containing EPS biofilms exposed to iron, then once again isolated from cultures of A. Actinomycetemcomitans. The electrophoresis and Western blotting were done on the isolated protein. Results The result showed that the the expression of specific proteins in EPS biofilm decreased in response to iron exposure. Conclusions Iron exposure could influenced the specific protein expression in EPS biofilm of Aggregatibacter Actinomycetemcomitans.

  • Antimicrobial proteins of Snail mucus (Achatina fulica) against Streptococcus mutans and Aggregatibacter Actinomycetemcomitans
    Dental Journal: Majalah Kedokteran Gigi, 2014
    Co-Authors: Indah Listiana Kriswandini, Ester Arijani R
    Abstract:

    Background: Achasin and mytimacin-AF are proteins of snail mucus (Achatina fulica) which have antimicrobial activity. Snail mucus is suspected to have other proteins which have antimicrobial activity against Streptococcus mutans and Aggregatibacter Actinomycetemcomitans the oral pathologic bacteria. Purpose: The study were aimed to characterize the proteins of snail mucus (Achatina fulica) that have antimicrobial activities to Streptococcus mutans and Actinobacillus Actinomycetemcomitans, and to compared the antimicrobial effect of achasin and mytimacin-AF. Methods: The sample of study was the mucus of snails which were taken from Yogyakarta Province. The isolation and characterization of protein were conducted by using SDS-PAGE method, electroelution, and dialysis. Nano drop test was conducted to determine protein concentration. The sensitivity test was conducted by using dilution test, and followed by spectrophotometry and paper disc diffusion tests. Results: The study showed that proteins successfully characterized from snail mucus (Achatina fulica) were proteins with molecular weights of 83.67 kDa (achasin), 50.81 kDa, 15 kDa, 11.45 kDa (full amino acid sequence of mytimacin-AF) and 9.7 kDa (mytimacin-AF). Based on the dilution test, Achasin had better antimicrobial activities against Streptococcus mutans, while mytimacin-AF had better antimicrobial activities against Aggregatibacter Actinomycetemcomitans. But the paper disc diffusion test result showed that Achasin had antimicrobial activities against Streptococcus mutans and Aggregatibacter Actinomycetemcomitans, while mytimacin-AF had no antimicrobial activities. Conclusion: The proteins with molecular weights of 50.81 kDa, 15 kDa, 11.45 kDa were considered as new antimicrobial proteins isolated from snail mucus. Achasin, had better antimicrobial activities against Streptococcus mutans, while mytimacin-AF had better antimicrobial activities against Aggregatibacter Actinomycetemcomitans. Latar belakang: Achasin dan mytimacin-AF adalah protein lendir bekicot (Achatina fulica) yang memiliki aktivitas antimikroba. Lendir bekicot diduga memiliki protein lain yang memiliki aktivitas antimikroba terhadap Streptococcus mutans dan Actinobacillus Actinomycetemcomitans bakteri patologis oral. Tujuan: Penelitian ini bertujuan untuk mengkarakterisasi protein lendir bekicot (Achatina fulica) yang memiliki aktivitas antimikroba terhadap Streptococcus mutans dan Aggretibacter Actinomycetemcomitans, dan membandingkan efek antimikroba protein achasin dan mytimacin-AF. Metode: Sampel penelitian adalah lendir bekicot yang diambil dari Provinsi Yogyakarta. Isolasi dan karakterisasi protein dilakukan dengan metode SDS-PAGE, elektro-elusi, dan dialisis. Nano drop test dilakukan untuk menentukan konsentrasi protein. Uji sensitivitas dilakukan dengan menggunakan uji dilusi, dan diikuti oleh spektrofotometri dan tes difusi kertas cakram. Hasil: Protein dari lendir bekicot (Achatina fulica) yang ditemukan adalah protein dengan berat molekul 83,67 kDa (achasin), 50,81 kDa, 15 kDa, 11,45 kDa (urutan asam amino penuh mytimacin-AF) dan 9,7 kDa (mytimacin- AF). Berdasarkan uji dilusi, Achasin memiliki aktivitas antimikroba yang lebih baik terhadap Streptococcus mutans, sedangkan mytimacin-AF memiliki aktivitas antimikroba yang lebih baik terhadap Aggregatibacter Actinomycetemcomitans. Namun hasil uji difusi cakram kertas menunjukkan bahwa Achasin memiliki aktivitas antimikroba terhadap Streptococcus mutans dan Aggegatibacter Actinomycetemcomitans, sementara mytimacin-AF tidak memiliki kegiatan antimikroba. Simpulan: Protein dengan berat molekul 50,81 kDa, 15 kDa, 11,45 kDa merupakan protein antimikroba baru diisolasi dari lendir bekicot. Achasin, memiliki aktivitas antimikroba yang lebih baik terhadap Streptococcus mutans, sedangkan mytimacin-AF memiliki aktivitas antimikroba yang lebih baik terhadap Actinobacillus Actinomycetemcomitans.