Non-invasive Imaging of Disseminated Candidiasis in Zebrafish Larvae

Disseminated candidiasis caused by the pathogen Candida albicans is a clinically important problem in hospitalized individuals and is associated with a 30 ...

Modeling Mucosal Candidiasis in Larval Zebrafish by Swimbladder Injection

Early defense against mucosal pathogens consists of both an epithelial barrier and innate immune cells. The immunocompetency of both, and their ...

University of Maine

Microrna &#x4E30;&#x5BCC;&#x52A8;&#x7269;&#x57FA;&#x56E0;&#x7EC4;&#x4E2D;&#xFF0C;&#x5E76;&#x9884;&#x8BA1;&#x5728;&#x5E7F;&#x6CDB;&#x7684;&#x57FA;&#x56E0;&#x8868;&#x8FBE;&#x65B9;&#x6848;&#x6709;&#x91CD;&#x8981;&#x7684;&#x4F5C;&#x7528;&#x3002;&#x8FD9;&#x7A81;&#x51FA;&#xFF0C;&#x5C3D;&#x7BA1;&#x6709;&#x5173;&#x4E8E;&#x4E2A;&#x522B;&#x54FA;&#x4E73;&#x52A8;&#x7269; Microrna &#x7684;&#x529F;&#x80FD;&#x77E5;&#x8BC6;&#x7684;&#x7F3A;&#x4E4F;&#x3002;&#x4F7F;&#x7528;&#x529F;&#x80FD;&#x635F;&#x5931;&#x7684;&#x7B49;&#x4F4D;&#x57FA;&#x56E0;&#x5728;&#x5C0F;&#x9F20;&#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x62A5;&#x544A;&#x5728;&#x8FD9;&#x91CC;&#x5728;&#x9AD3;&#x7CFB;&#x7279;&#x5B9A; microRNA-223 (miR-223&#xFF09; &#x4E0D;&#x5229;&#x89C4;&#x7BA1;&#x7956;&#x6269;&#x6563;&#x548C;&#x7C92;&#x7EC6;&#x80DE;&#x5206;&#x5316;&#x548C;&#x6FC0;&#x6D3B;&#x3002;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9;-223 &#xFF08;&#x4E5F;&#x79F0;&#x4E3A; Mirn223) &#x57FA;&#x56E0;&#x7A81;&#x53D8;&#x5C0F;&#x9F20;&#x5DF2;&#x5F15;&#x8D77;&#x7C92;&#x7EC6;&#x80DE;&#x7956;&#x7EC6;&#x80DE;&#x7684;&#x6570;&#x76EE;&#x589E;&#x52A0;&#x4E86;&#x7EC6;&#x80DE;&#x81EA;&#x4E3B;&#x6269;&#x5927;&#x7C92;&#x7EC6;&#x80DE;&#x8F66;&#x53A2;&#x3002;&#x6211;&#x4EEC;&#x663E;&#x793A; Mef2c&#xFF0C;&#x4FC3;&#x8FDB;&#x7C92;&#x7EC6;&#x80DE;&#x7684;&#x524D;&#x4F53;&#x7EC6;&#x80DE;&#x589E;&#x6B96;&#x7684;&#x8F6C;&#x5F55;&#x56E0;&#x5B50;&#x662F;&#x76EE;&#x6807;&#xFF0C;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9;-223&#xFF0C;&#x548C; Mef2c&#xFF0C;&#x9057;&#x4F20;&#x6D88;&#x878D;&#x53D6;&#x6D88;&#x7956;&#x6269;&#x5F20;&#x5E76;&#x7EA0;&#x6B63;&#x5728;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9; 223 &#x7A7A;&#x5C0F;&#x9F20;&#x7684;&#x4E2D;&#x6027;&#x7C92;&#x7EC6;&#x80DE;&#x8868;&#x578B;&#x3002;&#x6B64;&#x5916;&#xFF0C;&#x7C92;&#x7EC6;&#x80DE;&#x7F3A;&#x4E4F;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9; 223 &#x662F;&#x524D;&#x623F;&#xFF0C;&#x6FC0;&#x6D3B;&#x523A;&#x6FC0;&#x8FC7;&#x654F;&#xFF0C;&#x663E;&#x793A;&#x589E;&#x52A0;&#x7684;&#x6740;&#x83CC;&#x6D3B;&#x6027;&#x3002;&#x7531;&#x4E8E;&#x6B64;&#x4E2D;&#x6027;&#x7C92;&#x7EC6;&#x80DE;&#x591A;&#x52A8;&#xFF0C;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9; 223 &#x57FA;&#x56E0;&#x7A81;&#x53D8;&#x5C0F;&#x9F20;&#x81EA;&#x53D1;&#x53D1;&#x5C55;&#x708E;&#x75C7;&#x80BA;&#x75C5;&#x7406;&#x5B66;&#x548C;&#x5C55;&#x54C1;&#x540E;&#x5185;&#x6BD2;&#x7D20;&#x6311;&#x6218;&#x5938;&#x5F20;&#x7684;&#x7EC4;&#x7EC7;&#x7834;&#x574F;&#x3002;&#x6211;&#x4EEC;&#x7684;&#x6570;&#x636E;&#x652F;&#x6301;&#x7684;&#x6A21;&#x578B;&#x5728;&#x548C;&#x5E73;&#x53F7;&#x7A7A;&#x95F4;&#x7AD9; 223 &#x4F5C;&#x4E3A; fine-tuner &#x7684;&#x7C92;&#x7EC6;&#x80DE;&#x751F;&#x4EA7;&#x548C;&#x708E;&#x75C7;&#x53CD;&#x5E94;&#x3002;

MicroRNA 223 &#x7956;&#x7EC6;&#x80DE;&#x589E;&#x6B96;&#x548C;&#x7C92;&#x7EC6;&#x80DE;&#x529F;&#x80FD;&#x7684;&#x8C03;&#x8282;&#x3002;

MicroRNAs are abundant in animal genomes and have been predicted to have important roles in a broad range of gene expression programmes. Despite this prominence, there is a dearth of functional knowledge regarding individual mammalian microRNAs. Using a loss-of-function allele in mice, we report here that the myeloid-specific microRNA-223 (miR-223) negatively regulates progenitor proliferation and granulocyte differentiation and activation. miR-223 (also called Mirn223) mutant mice have an expanded granulocytic compartment resulting from a cell-autonomous increase in the number of granulocyte progenitors. We show that Mef2c, a transcription factor that promotes myeloid progenitor proliferation, is a target of miR-223, and that genetic ablation of Mef2c suppresses progenitor expansion and corrects the neutrophilic phenotype in miR-223 null mice. In addition, granulocytes lacking miR-223 are hypermature, hypersensitive to activating stimuli and display increased fungicidal activity. As a consequence of this neutrophil hyperactivity, miR-223 mutant mice spontaneously develop inflammatory lung pathology and exhibit exaggerated tissue destruction after endotoxin challenge. Our data support a model in which miR-223 acts as a fine-tuner of granulocyte production and the inflammatory response.

Regulation of progenitor cell proliferation and granulocyte function by microRNA-223.

MicroARN sont abondants dans les g&eacute;nomes animaux et ont &eacute;t&eacute; pr&eacute;dits &agrave; jouer un r&ocirc;le important dans un large &eacute;ventail de programmes d&#39;expression de g&egrave;ne. Malgr&eacute; cette importance, il y a un manque de connaissance fonctionnelle en ce qui concerne les microARN mammif&egrave;res individuels. &Agrave; l&#39;aide d&#39;un all&egrave;le de la perte de fonction chez la souris, nous rapportons ici que les microARN my&eacute;lo&iuml;de sp&eacute;cifiques-223 (miR-223) r&eacute;gule n&eacute;gativement l&#39;activation et la prolif&eacute;ration et granulocytes la diff&eacute;renciation des prog&eacute;niteurs. miR-223 (&eacute;galement appel&eacute; Mirn223) de souris mutantes ont un compartiment granulocytaire &eacute;largi r&eacute;sultant d&#39;une augmentation de cellule autonome dans le nombre de g&eacute;niteurs de granulocytes. Nous montrons que le Mef2c, un facteur de transcription qui favorise la prolif&eacute;ration des prog&eacute;niteurs my&eacute;lo&iuml;des, est une cible de miR-223, et que l&#39;ablation g&eacute;n&eacute;tique du Mef2c supprime l&#39;expansion de l&#39;anc&ecirc;tre et corrige le ph&eacute;notype neutrophilique chez les souris null miR-223. En outre, les granulocytes manque miR-223 sont hypermature, hypersensible &agrave; l&#39;activation des stimuli et affichent l&#39;augmentation de l&#39;activit&eacute; fongicide. Par suite de cette hyperactivit&eacute; neutrophile, miR-223 souris mutantes spontan&eacute;ment d&eacute;veloppent la pathologie inflammatoire pulmonaire et pi&egrave;ce de destruction tissulaire exag&eacute;r&eacute; apr&egrave;s le d&eacute;fi de l&#39;endotoxine. Nos donn&eacute;es supportent un mod&egrave;le dans lequel miR-223 sert une fine de la production de granulocytes et de la r&eacute;ponse inflammatoire.

R&egrave;glement des prog&eacute;niteurs prolif&eacute;ration et granulocytes fonction des cellules par micro-ARN-223.

MicroRNAs sind reichlich in tierischen Genome und haben wichtige Rollen in einer Vielzahl von Gen-Ausdruck-Programme haben vorhergesagt worden. Trotz dieser Bekanntheit gibt es ein Mangel an funktionalen wissen &uuml;ber einzelne S&auml;ugetier-MicroRNAs. Verwenden ein Loss of Function-Allel, bei M&auml;usen, berichten wir hier, dass der myeloid-spezifische MicroRNA-223 (MiR-223) negativ Vorl&auml;uferzellen Proliferation und Granulozyten Differenzierung und Aktivierung regelt. MiR-223 (auch genannt Mirn223) mutierte M&auml;use haben eine erweiterte granulocytic Fach aus einer Zelle-autonome Zunahme der Zahl von Vorl&auml;uferzellen der Granulozyten. Wir zeigen, dass Mef2c, einen Transkriptionsfaktor, der myeloischen Vorl&auml;uferzellen Verbreitung, f&ouml;rdert ein Ziel von MiR-223 ist, und dieser genetischen Ablation der Mef2c unterdr&uuml;ckt Stammvater Ausbau und korrigiert die neutrophile Ph&auml;notyp in MiR-223 null M&auml;use. Dar&uuml;ber hinaus fehlt MiR-223 Granulozyten sind Hypermature, &uuml;berempfindlich auf Reize aktivieren und erh&ouml;hten pilzt&ouml;tende Aktivit&auml;t anzeigen. Als Folge dieser neutrophil Hyperaktivit&auml;t MiR-223 Mutante M&auml;use spontan entz&uuml;ndliche Lunge Pathologie zu entwickeln und zeigen eine &uuml;bertriebene Gewebezerst&ouml;rung nach Endotoxin-Challenge. Unsere Daten unterst&uuml;tzen ein Modell, in dem MiR-223 als eine Feinstimmers der Granulozyten-Produktion und die entz&uuml;ndliche Reaktion fungiert.

Regulierung der Vorl&auml;uferzellen Proliferation und Granulozyten Zellfunktionen durch MicroRNA-223.

MicroRNA &egrave; abbondanti nei genomi animali ed essere stata prevista ad per avere ruoli importanti in un&#39;ampia gamma di programmi di espressione genica. Nonostante questo rilievo, c&#39;&egrave; una carenza di conoscenze funzionali per quanto riguarda singoli microRNA nei mammiferi. Utilizzando un allele di perdita di funzione nei topi, riportiamo qui che la mieloide specifici microRNA-223 (miR-223) regola negativamente la attivazione e differenziazione di proliferazione e granulociti progenitore. topi mutanti miR-223 (anche denominato Mirn223) hanno un vano granulocitica espanso risultanti da un cellula autonomo aumento del numero di progenitori granulociti. Mostriamo che Mef2c, un fattore di trascrizione che promuove la proliferazione del progenitore mieloide, &egrave; una destinazione di miR-223, e che l&#39;ablazione genetica di Mef2c sopprime espansione progenitore e corregge il fenotipo neutrofila nei topi null miR-223. Inoltre, granulociti privo di miR-223 sono hypermature, ipersensibili a stimoli di attivazione e visualizzare aumentata attivit&agrave; fungicida. Come conseguenza di questa iperattivit&agrave; dei neutrofili, miR-223 topi mutanti spontaneamente sviluppano patologia infiammatoria polmonare ed esibiscono distruzione tissutale esagerato dopo la sfida di endotossine. I nostri dati supportano un modello in cui miR-223 agisce come un fine-tuner della produzione di granulociti e la risposta infiammatoria.

Regolamento del progenitor cell proliferazione e granulociti funzione di microRNA-223.

&#x30DE;&#x30A4;&#x30AF;&#x30ED; Rna &#x306F;&#x52D5;&#x7269;&#x30B2;&#x30CE;&#x30E0;&#x3067;&#x8C4A;&#x5BCC;&#x3067;&#x3042;&#x308B;&#x3057;&#x3001;&#x907A;&#x4F1D;&#x5B50;&#x767A;&#x73FE;&#x30D7;&#x30ED;&#x30B0;&#x30E9;&#x30E0;&#x306E;&#x5E83;&#x3044;&#x7BC4;&#x56F2;&#x3067;&#x91CD;&#x8981;&#x306A;&#x5F79;&#x5272;&#x3092;&#x6301;&#x3064;&#x3053;&#x3068;&#x3092;&#x4E88;&#x6E2C;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x3053;&#x306E;&#x9686;&#x8D77;&#x306B;&#x3082;&#x304B;&#x304B;&#x308F;&#x3089;&#x305A;&#x500B;&#x3005; &#x306E;&#x54FA;&#x4E73;&#x985E;&#x306E;&#x30DE;&#x30A4;&#x30AF;&#x30ED; Rna &#x306B;&#x95A2;&#x3059;&#x308B;&#x6A5F;&#x80FD;&#x7684;&#x77E5;&#x8B58;&#x306E;&#x4E0D;&#x8DB3;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x640D;&#x5931;&#x95A2;&#x6570;&#x306E;&#x5BFE;&#x7ACB;&#x907A;&#x4F1D;&#x5B50;&#x306E;&#x30DE;&#x30A6;&#x30B9;&#x3092;&#x4F7F;&#x7528;&#x3057;&#x3066;&#x3001;&#x3053;&#x3053;&#x3067;&#x7279;&#x5B9A;&#x306E;&#x9AA8;&#x9AC4;&#x6027;&#x30DE;&#x30A4;&#x30AF;&#x30ED; Rna-223 &#xFF08;&#x30DF;&#x30FC;&#x30EB;-223) &#x5426;&#x5B9A;&#x7684;&#x306B;&#x524D;&#x99C6;&#x7D30;&#x80DE;&#x306E;&#x5897;&#x6B96;&#x3068;&#x9846;&#x7C92;&#x7403;&#x306E;&#x5206;&#x5316;&#x3068;&#x6D3B;&#x6027;&#x5316;&#x3092;&#x8ABF;&#x7BC0;&#x3059;&#x308B;&#x3053;&#x3068;&#x5831;&#x544A;&#x66F8;&#x3057;&#x307E;&#x3059;&#x3002;&#x30DF;&#x30FC;&#x30EB;-223 (&#x307E;&#x305F;&#x547C;&#x3070;&#x308C;&#x308B; Mirn223) &#x5909;&#x7570;&#x30DE;&#x30A6;&#x30B9;&#x9846;&#x7C92;&#x7403;&#x524D;&#x99C6;&#x7D30;&#x80DE;&#x306E;&#x6570;&#x306E;&#x30BB;&#x30EB;&#x81EA;&#x5F8B;&#x306E;&#x5897;&#x52A0;&#x304B;&#x3089;&#x751F;&#x3058;&#x308B;&#x3001;&#x62E1;&#x5F35;&#x3055;&#x308C;&#x305F;&#x9846;&#x7C92;&#x306E;&#x30B3;&#x30F3;&#x30D1;&#x30FC;&#x30C8;&#x30E1;&#x30F3;&#x30C8;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x6211;&#x3005; &#x306F;&#x9AA8;&#x9AC4;&#x524D;&#x99C6;&#x7D30;&#x80DE;&#x306E;&#x5897;&#x6B96;&#x3092;&#x4FC3;&#x9032;&#x3059;&#x308B;&#x8EE2;&#x5199;&#x56E0;&#x5B50; Mef2c &#x30DF;&#x30FC;&#x30EB;-223 &#x306E;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x3067;&#x3001;&#x305D;&#x306E;&#x907A;&#x4F1D;&#x5B50;&#x30A2;&#x30D6;&#x30EC;&#x30FC;&#x30B7;&#x30E7;&#x30F3; Mef2c &#x306E;&#x524D;&#x99C6;&#x62E1;&#x5927;&#x3092;&#x6291;&#x5236;&#x3057;&#x3066;&#x30DF;&#x30FC;&#x30EB; 223 &#x6B20;&#x640D;&#x30DE;&#x30A6;&#x30B9;&#x306B;&#x304A;&#x3051;&#x308B;&#x597D;&#x4E2D;&#x7403;&#x306E;&#x8868;&#x73FE;&#x578B;&#x3092;&#x4FEE;&#x6B63;&#x3092;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x307E;&#x305F;&#x3001;&#x30DF;&#x30FC;&#x30EB; 223 &#x6B20;&#x3051;&#x3066;&#x9846;&#x7C92;&#x7403;&#x904E;&#x719F;&#x3001;&#x523A;&#x6FC0;&#x6D3B;&#x6027;&#x5316;&#x306B;&#x904E;&#x654F;&#x3055;&#x308C;&#x5897;&#x52A0;&#x6BBA;&#x83CC;&#x6D3B;&#x6027;&#x3092;&#x8868;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x3053;&#x306E;&#x597D;&#x4E2D;&#x7403;&#x306E;&#x591A;&#x52D5;&#x6027;&#x306E;&#x7D50;&#x679C;&#x3068;&#x3057;&#x3066;&#x30DF;&#x30FC;&#x30EB; 223 &#x5909;&#x7570;&#x30DE;&#x30A6;&#x30B9;&#x306F;&#x81EA;&#x767A;&#x7684;&#x306B;&#x708E;&#x75C7;&#x6027;&#x80BA;&#x306E;&#x75C5;&#x7406;&#x3092;&#x958B;&#x767A;&#x3057;&#x3001;&#x8A87;&#x5F35;&#x3055;&#x308C;&#x305F;&#x30C6;&#x30A3;&#x30C3;&#x30B7;&#x30E5;&#x306E;&#x7834;&#x58CA;&#x5F8C;&#x30A8;&#x30F3;&#x30C9;&#x30C8;&#x30AD;&#x30B7;&#x30F3; &#x30C1;&#x30E3;&#x30EC;&#x30F3;&#x30B8;&#x3092;&#x5C55;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x79C1;&#x305F;&#x3061;&#x306E;&#x30C7;&#x30FC;&#x30BF; &#x30DF;&#x30FC;&#x30EB; 223 &#x304C;&#x9846;&#x7C92;&#x7403;&#x751F;&#x7523;&#x306E; fine-tuner &#x3068;&#x708E;&#x75C7;&#x6027;&#x306E;&#x5FDC;&#x7B54;&#x3068;&#x3057;&#x3066;&#x4F5C;&#x7528;&#x30E2;&#x30C7;&#x30EB;&#x3092;&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3057;&#x307E;&#x3059;&#x3002;

&#x30DE;&#x30A4;&#x30AF;&#x30ED; Rna 223 &#x306B;&#x3088;&#x308B;&#x524D;&#x99C6;&#x7D30;&#x80DE;&#x306E;&#x5897;&#x6B96;&#x3068;&#x9846;&#x7C92;&#x7403;&#x6A5F;&#x80FD;&#x306E;&#x8ABF;&#x7BC0;&#x3002;

MicroRNAs &#xB3D9;&#xBB3C; &#xAC8C;&#xB188;&#xC5D0;&#xC11C; &#xD48D;&#xBD80; &#xD558; &#xACE0; &#xAD11;&#xBC94;&#xC704; &#xD55C; &#xC720;&#xC804;&#xC790; &#xC2DD; &#xD504;&#xB85C;&#xADF8;&#xB7A8;&#xC5D0;&#xC5D0;&#xC11C; &#xC911;&#xC694; &#xD55C; &#xC5ED;&#xD560;&#xC744;&#xAC00;&#xC9C0;&#xACE0; &#xC608;&#xC0C1;. &#xC774; &#xB208;&#xC5D0;&#xC774; &#xB754;&#xC5D0;&#xB3C4; &#xBD88;&#xAD6C; &#xD558; &#xACE0; &#xAC1C;&#xBCC4; &#xD3EC;&#xC720;&#xB958; Micrornas&#xC5D0; &#xAD00;&#xD55C; &#xAE30;&#xB2A5; &#xC9C0;&#xC2DD;&#xC758; &#xBD80;&#xC871;&#xC774; &#xC774;&#xB2E4;. &#xB9C8;&#xC6B0;&#xC2A4; &#xAE30;&#xB2A5; &#xC190;&#xC2E4;&#xC744; &#xB300;&#xB9BD; &#xC720;&#xC804;&#xC790;&#xB97C; &#xC0AC;&#xC6A9;, &#xC6B0;&#xB9AC; &#xBCF4;&#xACE0; &#xC5EC;&#xAE30; &#xACE8;&#xC218;&#xC131; &#xD2B9;&#xC815; microRNA-223 (&#xBBF8;&#xB974;-223) &#xBD80;&#xC815;&#xC801;&#xC778; &#xC870;&#xC0C1; &#xD655;&#xC0B0; &#xBC0F; granulocyte &#xBD84;&#xD654;&#xC640; &#xD65C;&#xC131;&#xD654; &#xC870;&#xC808; &#xD569;&#xB2C8;&#xB2E4;. &#xBBF8;&#xB974;-223 (&#xB610;&#xD55C; &#xBD88;&#xB9AC; &#xC6B4;&#xB41C; Mirn223) &#xB3CC;&#xC5F0;&#xBCC0;&#xC774; &#xC0DD;&#xC950;&#xAC00; &#xD655;&#xC7A5; &#xB41C; granulocytic &#xAD6C;&#xD68D; granulocyte progenitors &#xC218; &#xC140; &#xC790;&#xCE58; &#xC99D;&#xAC00;&#xC5D0;&#xC11C; &#xBC1C;&#xC0DD; &#xD569;&#xB2C8;&#xB2E4;. &#xC6B0;&#xB9AC; Mef2c, &#xACE8;&#xC218;&#xC131; &#xC870;&#xC0C1; &#xD655;&#xC0B0;&#xC744; &#xCD09;&#xC9C4; &#xD558;&#xB294; &#xC804;&#xC0AC; &#xC778;&#xC790;&#xB294; &#xBBF8;&#xB974;-223, &#xB300;&#xC0C1; &#xBC0F; mef2c&#xC758; &#xC720;&#xC804;&#xC801; &#xC808;&#xC81C; &#xADF8; &#xC870;&#xC0C1; &#xD655;&#xC7A5;&#xC744; &#xC5B5;&#xC81C; &#xD558; &#xACE0; &#xBBF8;&#xB974;-223 null &#xC950;&#xC5D0; neutrophilic &#xD615; &#xC218;&#xC815; &#xBCF4;&#xC5EC; &#xC90D;&#xB2C8;&#xB2E4;. &#xB610;&#xD55C;, granulocytes &#xBD80;&#xC871; &#xD55C; &#xBBF8;&#xB974;-223 hypermature, &#xACFC;&#xBBFC; &#xC790;&#xADF9;&#xC744; &#xD65C;&#xC131;&#xD654; &#xD558; &#xACE0; &#xC0B4; &#xADE0; &#xC81C;&#xC758; &#xD65C;&#xB3D9;&#xC744; &#xC99D;&#xAC00; &#xD45C;&#xC2DC;. &#xC774; &#xD638; &#xACFC;&#xB2E4;&#xC758; &#xACB0;&#xACFC;&#xB85C; &#xBBF8;&#xB974;-223 &#xB3CC;&#xC5F0;&#xBCC0;&#xC774; &#xC0DD;&#xC950; &#xC790;&#xBC1C;&#xC801;&#xC73C;&#xB85C; &#xC5FC;&#xC99D; &#xC131; &#xD3D0; &#xBCD1; &#xB9AC;&#xB97C; &#xAC1C;&#xBC1C; &#xD558; &#xACE0; &#xC120;&#xCC98;&#xB9AC; &#xB3C4;&#xC804; &#xD6C4; &#xACFC;&#xC7A5; &#xB41C; &#xC870;&#xC9C1;&#xC758; &#xD30C;&#xAD34;&#xB97C; &#xC804;&#xC2DC;. &#xC6B0;&#xB9AC;&#xC758; &#xB370;&#xC774;&#xD130; &#xBBF8;&#xB974;-223 granulocyte &#xC0DD;&#xC0B0; fine-tuner &#xBC0F; &#xC5FC;&#xC99D; &#xC131; &#xBC18;&#xC751;&#xC73C;&#xB85C; &#xC5ED;&#xD560; &#xBAA8;&#xB378;&#xC744; &#xC9C0;&#xC6D0; &#xD569;&#xB2C8;&#xB2E4;.

MicroRNA-223&#xC73C;&#xB85C; &#xC870;&#xC0C1; &#xC138;&#xD3EC; &#xC99D;&#xC2DD;&#xACFC; granulocyte &#xAE30;&#xB2A5; &#xADDC;&#xC815;.

MicroRNAs son abundantes en los genomas animales y han sido prev&eacute; que tienen un papel importante en una amplia gama de programas de expresi&oacute;n g&eacute;nica. A pesar de esta importancia, hay una escasez de conocimientos funcionales sobre microRNAs mam&iacute;feros individuales. Usando un alelo de p&eacute;rdida de funci&oacute;n en ratones, Divulgamos aqu&iacute; que el mieloide espec&iacute;ficos microARN-223 (miR-223) regula negativamente la activaci&oacute;n y diferenciaci&oacute;n de proliferaci&oacute;n y granulocitos progenitor. ratones mutantes miR-223 (tambi&eacute;n llamado Mirn223) tienen un compartimiento granuloc&iacute;tico ampliado resultantes de un c&eacute;lula aut&oacute;nomo aumento en el n&uacute;mero de progenitores de granulocitos. Demostramos que Mef2c, un factor de transcripci&oacute;n que promueve la proliferaci&oacute;n de progenitoras mieloides, es un objetivo del miR-223, y que la ablaci&oacute;n gen&eacute;tica de Mef2c suprime la expansi&oacute;n de la progenitora y corrige el fenotipo neutrof&iacute;lico en ratones nulos miR-223. Adem&aacute;s, granulocitos falta miR-223 son hipermadura, hipersensible a la activaci&oacute;n de est&iacute;mulos y Mostrar mayor actividad fungicida. Como consecuencia de esta hiperactividad neutr&oacute;fila, miR-223 ratones mutantes espont&aacute;neamente desarrollan patolog&iacute;a pulmonar inflamatoria y exhiben la destrucci&oacute;n del tejido exagerado despu&eacute;s del desaf&iacute;o de endotoxina. Nuestros datos apoyan un modelo en el que el miR-223 act&uacute;a como un fine-tuner de la producci&oacute;n de granulocitos y la respuesta inflamatoria.

Regulaci&oacute;n de la funci&oacute;n de proliferaci&oacute;n y granulocitos de c&eacute;lulas progenitoras de microARN-223.

The interaction of Candida albicans with phagocytes of the host's innate immune system is highly dynamic, and its outcome directly impacts the progression of infection. While the switch to hyphal growth within the macrophage is the most obvious physiological response, much of the genetic response reflects nutrient starvation: translational repression and induction of alternative carbon metabolism. Changes in amino acid metabolism are not seen, with the striking exception of arginine biosynthesis, which is upregulated in its entirety during coculture with macrophages. Using single-cell reporters, we showed here that arginine biosynthetic genes are induced specifically in phagocytosed cells. This induction is lower in magnitude than during arginine starvation in vitro and is driven not by an arginine deficiency within the phagocyte but instead by exposure to reactive oxygen species (ROS). Curiously, these genes are induced in a narrow window of sublethal ROS concentrations. C. albicans cells phagocytosed by primary macrophages deficient in the gp91(phox) subunit of the phagocyte oxidase do not express the ARG pathway, indicating that the induction is dependent on the phagocyte oxidative burst. C. albicans arg pathway mutants are retarded in germ tube and hypha formation within macrophages but are not notably more sensitive to ROS. We also find that the ARG pathway is regulated not by the general amino acid control response but by transcriptional regulators similar to the Saccharomyces cerevisiae ArgR complex. In summary, phagocytosis induces this single amino acid biosynthetic pathway in an ROS-dependent manner.

Candida albicans induces arginine biosynthetic genes in response to host-derived reactive oxygen species.

The epithelium performs a balancing act at the interface between an animal and its environment to enable both pathogen killing and tolerance of commensal microorganisms. Candida albicans is a clinically important human commensal that colonizes all human mucosal surfaces, yet is largely prevented from causing mucosal infections in immunocompetent individuals. Despite the importance of understanding host-pathogen interactions at the epithelium, no immunocompetent vertebrate model has been used to visualize these dynamics non-invasively. Here we demonstrate important similarities between swimbladder candidiasis in the transparent zebrafish and mucosal infection at the mammalian epithelium. Specifically, in the zebrafish swimmbladder infection model, we show dimorphic fungal growth, both localized and tissue-wide epithelial NF-κB activation, induction of NF-κB -dependent proinflammatory genes, and strong neutrophilia. Consistent with density-dependence models of host response based primarily on tissue culture experiments, we show that only high-level infection provokes widespread activation of NF-κB in epithelial cells and induction of proinflammatory genes. Similar to what has been found using in vitro mammalian models, we find that epithelial NF-κB activation can occur at a distance from the immediate site of contact with epithelial cells. Taking advantage of the ability to non-invasively image infection and host signaling at high resolution, we also report that epithelial NF-κB activation is diminished when phagocytes control the infection. This is the first system to model host response to mucosal infection in the juvenile zebrafish, and offers unique opportunities to investigate the tripartite interactions of C. albicans, epithelium and immune cells in an intact host.

Mucosal candidiasis elicits NF-κB activation, proinflammatory gene expression and localized neutrophilia in zebrafish.

Candida albicans is a human commensal and clinically important fungal pathogen that grows as both yeast and hyphal forms during human, mouse and zebrafish infection. Reactive oxygen species (ROS) produced by NADPH oxidases play diverse roles in immunity, including their long-appreciated function as microbicidal oxidants. Here we demonstrate a non-traditional mechanistic role of NADPH oxidase in promoting phagocyte chemotaxis and intracellular containment of fungi to limit filamentous growth. We exploit the transparent zebrafish model to show that failed NADPH oxidase-dependent phagocyte recruitment to C. albicans in the first four hours post-infection permits fungi to germinate extracellularly and kill the host. We combine chemical and genetic tools with high-resolution time-lapse microscopy to implicate both phagocyte oxidase and dual-specific oxidase in recruitment, suggesting that both myeloid and non-myeloid cells promote chemotaxis. We show that early non-invasive imaging provides a robust tool for prognosis, strongly connecting effective early immune response with survival. Finally, we demonstrate a new role of a key regulator of the yeast-to-hyphal switching program in phagocyte-mediated containment, suggesting that there are species-specific methods for modulation of NADPH oxidase-independent immune responses. These novel links between ROS-driven chemotaxis and fungal dimorphism expand our view of a key host defense mechanism and have important implications for pathogenesis.

NADPH oxidase-driven phagocyte recruitment controls Candida albicans filamentous growth and prevents mortality.

Systemic Candida albicans infection causes high morbidity and mortality and is associated with neutropenia; however, the roles of other innate immune cells in pathogenesis are poorly defined. Here, using a mouse model of systemic candidiasis, we found that resident macrophages accumulated in the kidney, the main target organ of infection, and formed direct contacts with the fungus in vivo mainly within the first few hours after infection. Macrophage accumulation and contact with Candida were both markedly reduced in mice lacking chemokine receptor CX3CR1, which was found almost exclusively on resident macrophages in uninfected kidneys. Infected Cx3cr1-/- mice uniformly succumbed to Candida-induced renal failure, but exhibited clearance of the fungus in all other organs tested. Renal macrophage deficiency in infected Cx3cr1-/- mice was due to reduced macrophage survival, not impaired proliferation, trafficking, or differentiation. In humans, the dysfunctional CX3CR1 allele CX3CR1-M280 was associated with increased risk of systemic candidiasis. Together, these data indicate that CX3CR1-mediated renal resident macrophage survival is a critical innate mechanism of early fungal control that influences host survival in systemic candidiasis.

CX3CR1-dependent renal macrophage survival promotes Candida control and host survival.

Unique imaging tools and practical advantages have made zebrafish a popular model to investigate in vivo host-pathogen interactions. These studies have uncovered details of the mechanisms involved in several human infections. Until recently, studies using this versatile host were limited to viral and prokaryotic pathogens. Eukaryotic pathogens are a diverse group with a major impact on the human and fish populations. The relationships of eukaryote pathogens with their hosts are complex and many aspects remain obscure. The small and transparent zebrafish, with its conserved immune system and amenability to genetic manipulation, make it an exciting model for quantitative study of the core strategies of eukaryotic pathogens and their hosts. The only thing to do now is realize its potential for advancement of biomedical and aquaculture research.

Utilization of zebrafish for intravital study of eukaryotic pathogen-host interactions.

NADPH oxidases play key roles in immunity and inflammation that go beyond the production of microbicidal reactive oxygen species (ROS). The past decade has brought a new appreciation for the diversity of roles played by ROS in signalling associated with inflammation and immunity. NADPH oxidase activity affects disease outcome during infections by human pathogenic fungi, an important group of emerging and opportunistic pathogens that includes Candida, Aspergillus and Cryptococcus species. Here we review how alternative roles of NADPH oxidase activity impact fungal infection and how ROS signalling affects fungal physiology. Particular attention is paid to roles for NADPH oxidase in immune migration, immunoregulation in pulmonary infection, neutrophil extracellular trap formation, autophagy and inflammasome activity. These recent advances highlight the power and versatility of spatiotemporally controlled redox regulation in the context of infection, and point to a need to understand the molecular consequences of NADPH oxidase activity in the cell.

The complex roles of NADPH oxidases in fungal infection.

The virulence of Candida albicans in a mouse model of invasive candidiasis is dependent on the phospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE). Disruption of the PS synthase gene CHO1 (i.e., cho1Δ/Δ) eliminates PS and blocks the de novo pathway for PE biosynthesis. In addition, the cho1Δ/Δ mutant's ability to cause invasive disease is severely compromised. The cho1Δ/Δ mutant also exhibits cell wall defects, and in this study, it was determined that loss of PS results in decreased masking of cell wall β(1-3)-glucan from the immune system. In wild-type C. albicans, the outer mannan layer of the wall masks the inner layer of β(1-3)-glucan from exposure and detection by innate immune effector molecules like the C-type signaling lectin Dectin-1, which is found on macrophages, neutrophils, and dendritic cells. The cho1Δ/Δ mutant exhibits increases in exposure of β(1-3)-glucan, which leads to greater binding by Dectin-1 in both yeast and hyphal forms. The unmasking of β(1-3)-glucan also results in increased elicitation of TNF-α from macrophages in a Dectin-1-dependent manner. The role of phospholipids in fungal pathogenesis is an emerging field, and this is the first study showing that loss of PS in C. albicans results in decreased masking of β(1-3)-glucan, which may contribute to our understanding of fungus-host interactions.

Masking of β(1-3)-glucan in the cell wall of Candida albicans from detection by innate immune cells depends on phosphatidylserine.

The innate immune system is a critical line of defense against pathogenic fungi. Macrophages act at an early stage of infection, detecting and phagocytizing infectious propagules. To avoid killing at this stage, fungal pathogens use diverse strategies ranging from evasion of uptake to intracellular parasitism. This article will discuss five of the most important human fungal pathogens (Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans, Coccidiodes immitis, and Histoplasma capsulatum) and consider the strategies and virulence factors adopted by each to survive and replicate within macrophages.

Robert T. Wheeler

Department of Molecular and Biomedical Sciences,
Graduate School of Biomedical Sciences and Engineering

University of Maine

Non-invasive Imaging of Disseminated Candidiasis in Zebrafish Larvae

Modeling Mucosal Candidiasis in Larval Zebrafish by Swimbladder Injection

Robert T. Wheeler

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Molecular and Biomedical Sciences,Graduate School of Biomedical Sciences and Engineering

University of Maine

Non-invasive Imaging of Disseminated Candidiasis in Zebrafish Larvae

Modeling Mucosal Candidiasis in Larval Zebrafish by Swimbladder Injection

Department of Molecular and Biomedical Sciences,
Graduate School of Biomedical Sciences and Engineering