The Experts below are selected from a list of 2058 Experts worldwide ranked by ideXlab platform
Muhammad Qasim Shahid - One of the best experts on this subject based on the ideXlab platform.
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murine and human cathelicidins contribute differently to hallmarks of Mastitis induced by pathogenic prototheca bovis algae
Frontiers in Cellular and Infection Microbiology, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Paloma Araujo Cavalcante, Cameron G Knight, Eduardo R CoboAbstract:Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes Mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a Mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused Acute Mastitis in mice and induced Camp gene transcription. Whereas, Camp -/- and Camp +/+ littermates had similar local algae burden, Camp +/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp +/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
Scientific Reports, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and -II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production, although its pathogenesis is not well known. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.
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adherent invasive capacities of bovine associated aerococcus viridans contribute to pathogenesis of Acute Mastitis in a murine model
Veterinary Microbiology, 2019Co-Authors: Gang Liu, Jinhua Yin, Bo Han, H W Barkema, Muhammad Qasim Shahid, Jeroen De Buck, Eduardo R Cobo, J P Kastelic, Jian GaoAbstract:Aerococcus viridans, a firmicutes bacteria widespread in the environment, is increasingly isolated from humans and animals, especially cows with Mastitis. However, its pathogenicity in the bovine mammary gland is unclear. The objective was to explore pathogenic potential of putative virulent and avirulent A. viridans in murine systemic and intramammary infection and mechanistically in cultured bovine mammary epithelial cells (bMECs). Virulence of 9 strains of A. viridans, isolated from subclinical cases of Mastitis, was tested for their ability to kill mice when systemically inoculated. Two A. viridans strains, causing highest and lowest survival rate in mice, were selected further as putative avirulent and virulent strains, respectively. Staphylococcus aureus N305 was used as a positive control. After intramammary inoculation, the virulent strain survived and replicated in the murine mammary gland for 9 d, whereas the avirulent strain was eliminated within 3 d. The virulent strain induced a robust inflammatory reaction in the mammary gland, characterized by Acute histopathological changes, increased myeloperoxidase activity and higher expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) compared to the avirulent strain. The virulent strain produced CAMP factor and exhibited strong cytotoxic effects (LDH release) and adhering and invasive abilities in contact with bMECs. Adhesion and invasion of virulent strain to bMECs was further confirmed by scanning and transmission electron microscopy; there was severe damage, including cytomembrane disruption, swollen mitochondria and loss of organelles. In conclusion, the putative virulent strain of A. viridans activated a strong neutrophil-based inflammatory response in the mammary gland, attributed to its ability to adhere to and invade mammary epithelium.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
bioRxiv, 2019Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Abstract Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production by unknown mechanisms. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis. Author summary Bovine Mastitis (inflammation of the udder) reduces milk production and quality, causing huge economic losses in the dairy industry worldwide. Although the alga Prototheca zopfii is a major cause of Mastitis in dairy cows, mechanisms by which it damages mammary tissues are not well known. Here, we used cell cultures and a mouse model of Mastitis to determine how Prototheca caused inflammation and cell death in mammary tissues. Prototheca invaded mammary gland cells, from cattle and mice, as well as macrophages (white cells that take up and kill pathogens) and caused cell death by interfering with mitochondria. Furthermore, Prototheca causes severe inflammation and tissue damage when injected into the mammary glands of mice. Although there are two genotypes of P. zopfii, only genotype II causes tissue damage, whereas gentotype I, common in farm environments, does not damage mammary tissues. Since P. zopfii is an alga and not a bacterium, antibiotic treatments, frequently used to treat Mastitis in cattle, are not effective against this organism. Understanding how P. zopfii damages mammary tissue and causes Mastitis is important new knowledge to promote future development of evidence-based approaches to prevent and treat mammary gland infections with this organism.
J P Kastelic - One of the best experts on this subject based on the ideXlab platform.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
Scientific Reports, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and -II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production, although its pathogenesis is not well known. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.
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adherent invasive capacities of bovine associated aerococcus viridans contribute to pathogenesis of Acute Mastitis in a murine model
Veterinary Microbiology, 2019Co-Authors: Gang Liu, Jinhua Yin, Bo Han, H W Barkema, Muhammad Qasim Shahid, Jeroen De Buck, Eduardo R Cobo, J P Kastelic, Jian GaoAbstract:Aerococcus viridans, a firmicutes bacteria widespread in the environment, is increasingly isolated from humans and animals, especially cows with Mastitis. However, its pathogenicity in the bovine mammary gland is unclear. The objective was to explore pathogenic potential of putative virulent and avirulent A. viridans in murine systemic and intramammary infection and mechanistically in cultured bovine mammary epithelial cells (bMECs). Virulence of 9 strains of A. viridans, isolated from subclinical cases of Mastitis, was tested for their ability to kill mice when systemically inoculated. Two A. viridans strains, causing highest and lowest survival rate in mice, were selected further as putative avirulent and virulent strains, respectively. Staphylococcus aureus N305 was used as a positive control. After intramammary inoculation, the virulent strain survived and replicated in the murine mammary gland for 9 d, whereas the avirulent strain was eliminated within 3 d. The virulent strain induced a robust inflammatory reaction in the mammary gland, characterized by Acute histopathological changes, increased myeloperoxidase activity and higher expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) compared to the avirulent strain. The virulent strain produced CAMP factor and exhibited strong cytotoxic effects (LDH release) and adhering and invasive abilities in contact with bMECs. Adhesion and invasion of virulent strain to bMECs was further confirmed by scanning and transmission electron microscopy; there was severe damage, including cytomembrane disruption, swollen mitochondria and loss of organelles. In conclusion, the putative virulent strain of A. viridans activated a strong neutrophil-based inflammatory response in the mammary gland, attributed to its ability to adhere to and invade mammary epithelium.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
bioRxiv, 2019Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Abstract Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production by unknown mechanisms. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis. Author summary Bovine Mastitis (inflammation of the udder) reduces milk production and quality, causing huge economic losses in the dairy industry worldwide. Although the alga Prototheca zopfii is a major cause of Mastitis in dairy cows, mechanisms by which it damages mammary tissues are not well known. Here, we used cell cultures and a mouse model of Mastitis to determine how Prototheca caused inflammation and cell death in mammary tissues. Prototheca invaded mammary gland cells, from cattle and mice, as well as macrophages (white cells that take up and kill pathogens) and caused cell death by interfering with mitochondria. Furthermore, Prototheca causes severe inflammation and tissue damage when injected into the mammary glands of mice. Although there are two genotypes of P. zopfii, only genotype II causes tissue damage, whereas gentotype I, common in farm environments, does not damage mammary tissues. Since P. zopfii is an alga and not a bacterium, antibiotic treatments, frequently used to treat Mastitis in cattle, are not effective against this organism. Understanding how P. zopfii damages mammary tissue and causes Mastitis is important new knowledge to promote future development of evidence-based approaches to prevent and treat mammary gland infections with this organism.
Eduardo R Cobo - One of the best experts on this subject based on the ideXlab platform.
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murine and human cathelicidins contribute differently to hallmarks of Mastitis induced by pathogenic prototheca bovis algae
Frontiers in Cellular and Infection Microbiology, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Paloma Araujo Cavalcante, Cameron G Knight, Eduardo R CoboAbstract:Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes Mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a Mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused Acute Mastitis in mice and induced Camp gene transcription. Whereas, Camp -/- and Camp +/+ littermates had similar local algae burden, Camp +/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp +/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
Scientific Reports, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and -II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production, although its pathogenesis is not well known. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.
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adherent invasive capacities of bovine associated aerococcus viridans contribute to pathogenesis of Acute Mastitis in a murine model
Veterinary Microbiology, 2019Co-Authors: Gang Liu, Jinhua Yin, Bo Han, H W Barkema, Muhammad Qasim Shahid, Jeroen De Buck, Eduardo R Cobo, J P Kastelic, Jian GaoAbstract:Aerococcus viridans, a firmicutes bacteria widespread in the environment, is increasingly isolated from humans and animals, especially cows with Mastitis. However, its pathogenicity in the bovine mammary gland is unclear. The objective was to explore pathogenic potential of putative virulent and avirulent A. viridans in murine systemic and intramammary infection and mechanistically in cultured bovine mammary epithelial cells (bMECs). Virulence of 9 strains of A. viridans, isolated from subclinical cases of Mastitis, was tested for their ability to kill mice when systemically inoculated. Two A. viridans strains, causing highest and lowest survival rate in mice, were selected further as putative avirulent and virulent strains, respectively. Staphylococcus aureus N305 was used as a positive control. After intramammary inoculation, the virulent strain survived and replicated in the murine mammary gland for 9 d, whereas the avirulent strain was eliminated within 3 d. The virulent strain induced a robust inflammatory reaction in the mammary gland, characterized by Acute histopathological changes, increased myeloperoxidase activity and higher expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) compared to the avirulent strain. The virulent strain produced CAMP factor and exhibited strong cytotoxic effects (LDH release) and adhering and invasive abilities in contact with bMECs. Adhesion and invasion of virulent strain to bMECs was further confirmed by scanning and transmission electron microscopy; there was severe damage, including cytomembrane disruption, swollen mitochondria and loss of organelles. In conclusion, the putative virulent strain of A. viridans activated a strong neutrophil-based inflammatory response in the mammary gland, attributed to its ability to adhere to and invade mammary epithelium.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
bioRxiv, 2019Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Abstract Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production by unknown mechanisms. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis. Author summary Bovine Mastitis (inflammation of the udder) reduces milk production and quality, causing huge economic losses in the dairy industry worldwide. Although the alga Prototheca zopfii is a major cause of Mastitis in dairy cows, mechanisms by which it damages mammary tissues are not well known. Here, we used cell cultures and a mouse model of Mastitis to determine how Prototheca caused inflammation and cell death in mammary tissues. Prototheca invaded mammary gland cells, from cattle and mice, as well as macrophages (white cells that take up and kill pathogens) and caused cell death by interfering with mitochondria. Furthermore, Prototheca causes severe inflammation and tissue damage when injected into the mammary glands of mice. Although there are two genotypes of P. zopfii, only genotype II causes tissue damage, whereas gentotype I, common in farm environments, does not damage mammary tissues. Since P. zopfii is an alga and not a bacterium, antibiotic treatments, frequently used to treat Mastitis in cattle, are not effective against this organism. Understanding how P. zopfii damages mammary tissue and causes Mastitis is important new knowledge to promote future development of evidence-based approaches to prevent and treat mammary gland infections with this organism.
H W Barkema - One of the best experts on this subject based on the ideXlab platform.
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murine and human cathelicidins contribute differently to hallmarks of Mastitis induced by pathogenic prototheca bovis algae
Frontiers in Cellular and Infection Microbiology, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Paloma Araujo Cavalcante, Cameron G Knight, Eduardo R CoboAbstract:Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes Mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a Mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused Acute Mastitis in mice and induced Camp gene transcription. Whereas, Camp -/- and Camp +/+ littermates had similar local algae burden, Camp +/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp +/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
Scientific Reports, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and -II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production, although its pathogenesis is not well known. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.
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adherent invasive capacities of bovine associated aerococcus viridans contribute to pathogenesis of Acute Mastitis in a murine model
Veterinary Microbiology, 2019Co-Authors: Gang Liu, Jinhua Yin, Bo Han, H W Barkema, Muhammad Qasim Shahid, Jeroen De Buck, Eduardo R Cobo, J P Kastelic, Jian GaoAbstract:Aerococcus viridans, a firmicutes bacteria widespread in the environment, is increasingly isolated from humans and animals, especially cows with Mastitis. However, its pathogenicity in the bovine mammary gland is unclear. The objective was to explore pathogenic potential of putative virulent and avirulent A. viridans in murine systemic and intramammary infection and mechanistically in cultured bovine mammary epithelial cells (bMECs). Virulence of 9 strains of A. viridans, isolated from subclinical cases of Mastitis, was tested for their ability to kill mice when systemically inoculated. Two A. viridans strains, causing highest and lowest survival rate in mice, were selected further as putative avirulent and virulent strains, respectively. Staphylococcus aureus N305 was used as a positive control. After intramammary inoculation, the virulent strain survived and replicated in the murine mammary gland for 9 d, whereas the avirulent strain was eliminated within 3 d. The virulent strain induced a robust inflammatory reaction in the mammary gland, characterized by Acute histopathological changes, increased myeloperoxidase activity and higher expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) compared to the avirulent strain. The virulent strain produced CAMP factor and exhibited strong cytotoxic effects (LDH release) and adhering and invasive abilities in contact with bMECs. Adhesion and invasion of virulent strain to bMECs was further confirmed by scanning and transmission electron microscopy; there was severe damage, including cytomembrane disruption, swollen mitochondria and loss of organelles. In conclusion, the putative virulent strain of A. viridans activated a strong neutrophil-based inflammatory response in the mammary gland, attributed to its ability to adhere to and invade mammary epithelium.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
bioRxiv, 2019Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Abstract Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production by unknown mechanisms. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis. Author summary Bovine Mastitis (inflammation of the udder) reduces milk production and quality, causing huge economic losses in the dairy industry worldwide. Although the alga Prototheca zopfii is a major cause of Mastitis in dairy cows, mechanisms by which it damages mammary tissues are not well known. Here, we used cell cultures and a mouse model of Mastitis to determine how Prototheca caused inflammation and cell death in mammary tissues. Prototheca invaded mammary gland cells, from cattle and mice, as well as macrophages (white cells that take up and kill pathogens) and caused cell death by interfering with mitochondria. Furthermore, Prototheca causes severe inflammation and tissue damage when injected into the mammary glands of mice. Although there are two genotypes of P. zopfii, only genotype II causes tissue damage, whereas gentotype I, common in farm environments, does not damage mammary tissues. Since P. zopfii is an alga and not a bacterium, antibiotic treatments, frequently used to treat Mastitis in cattle, are not effective against this organism. Understanding how P. zopfii damages mammary tissue and causes Mastitis is important new knowledge to promote future development of evidence-based approaches to prevent and treat mammary gland infections with this organism.
Cameron G Knight - One of the best experts on this subject based on the ideXlab platform.
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murine and human cathelicidins contribute differently to hallmarks of Mastitis induced by pathogenic prototheca bovis algae
Frontiers in Cellular and Infection Microbiology, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Paloma Araujo Cavalcante, Cameron G Knight, Eduardo R CoboAbstract:Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes Mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a Mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused Acute Mastitis in mice and induced Camp gene transcription. Whereas, Camp -/- and Camp +/+ littermates had similar local algae burden, Camp +/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp +/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
Scientific Reports, 2020Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and -II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production, although its pathogenesis is not well known. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis.
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prototheca zopfii genotype ii induces mitochondrial apoptosis in models of bovine Mastitis
bioRxiv, 2019Co-Authors: Muhammad Qasim Shahid, H W Barkema, Eduardo R Cobo, Liben Chen, Paloma Araujo Cavalcante, Siyu Xu, Cameron G Knight, J P KastelicAbstract:Abstract Prototheca zopfii is an alga increasingly isolated from bovine Mastitis. Of the two genotypes of P. zopfii (genotype I and II (GT-I and II)), P. zopfii GT-II is the genotype associated with Acute Mastitis and decreased milk production by unknown mechanisms. The objective was to determine inflammatory and apoptotic roles of P. zopfii GT-II in cultured mammary epithelial cells (from cattle and mice) and murine macrophages and using a murine model of Mastitis. Prototheca zopfii GT-II (but not GT-I) invaded bovine and murine mammary epithelial cells (MECs) and induced apoptosis, as determined by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling assay. This P. zopfii GT-II driven apoptosis corresponded to mitochondrial pathways; mitochondrial transmembrane resistance (ΔΨm) was altered and modulation of mitochondrion-mediated apoptosis regulating genes changed (increased transcriptional Bax, cytochrome-c and Apaf-1 and downregulated Bcl-2), whereas caspase-9 and -3 expression increased. Apoptotic effects by P. zopfii GT-II were more pronounced in macrophages compared to MECs. In a murine mammary infection model, P. zopfii GT-II replicated in the mammary gland and caused severe inflammation with infiltration of macrophages and neutrophils and upregulation of pro-inflammatory genes (TNF-α, IL-1β and Cxcl-1) and also apoptosis of epithelial cells. Thus, we concluded P. zopfii GT-II is a Mastitis-causing pathogen that triggers severe inflammation and also mitochondrial apoptosis. Author summary Bovine Mastitis (inflammation of the udder) reduces milk production and quality, causing huge economic losses in the dairy industry worldwide. Although the alga Prototheca zopfii is a major cause of Mastitis in dairy cows, mechanisms by which it damages mammary tissues are not well known. Here, we used cell cultures and a mouse model of Mastitis to determine how Prototheca caused inflammation and cell death in mammary tissues. Prototheca invaded mammary gland cells, from cattle and mice, as well as macrophages (white cells that take up and kill pathogens) and caused cell death by interfering with mitochondria. Furthermore, Prototheca causes severe inflammation and tissue damage when injected into the mammary glands of mice. Although there are two genotypes of P. zopfii, only genotype II causes tissue damage, whereas gentotype I, common in farm environments, does not damage mammary tissues. Since P. zopfii is an alga and not a bacterium, antibiotic treatments, frequently used to treat Mastitis in cattle, are not effective against this organism. Understanding how P. zopfii damages mammary tissue and causes Mastitis is important new knowledge to promote future development of evidence-based approaches to prevent and treat mammary gland infections with this organism.