Visualizing the Actin and Microtubule Cytoskeletons at the B-cell Immune Synapse Using Stimulated Emission Depletion (STED) Microscopy

B cells that bind to membrane-bound antigens (e.g., on the surface of an antigen-presenting cell) form an immune synapse, a specialized cellular structure ...

University of British Columbia

&#x5728;&#x53EF;&#x53D8;&#x533A;&#x57FA;&#x56E0;&#x514D;&#x75AB;&#x7403;&#x86CB;&#x767D; (IGV) &#x7684;&#x8D85; (&#x9655;&#x897F;&#x795E;&#x6728;) &#x4F53;&#x7EC6;&#x80DE;&#x53D8;&#x5F02;&#x81EA;&#x7136;&#x53D1;&#x751F;&#x5728; B &#x7EC6;&#x80DE;&#x53D1;&#x80B2;&#x63D0;&#x4F9B;&#x9AD8;&#x4EB2;&#x548C;&#x529B;&#x6297;&#x4F53;&#x7A84;&#x7A97;&#x53E3;&#x3002;&#x7136;&#x800C;&#xFF0C;&#x9655;&#x897F;&#x795E;&#x6728;&#x4E5F;&#x95ED;&#x5408;&#x76EE;&#x6807;&#x539F;&#x764C;&#x57FA;&#x56E0;&#xFF0C;&#x5BFC;&#x81F4;&#x57FA;&#x56E0;&#x7EC4;&#x4E0D;&#x7A33;&#x5B9A;&#x3002;&#x7279;&#x522B;&#x662F;&#x5728;&#x5F25;&#x6F2B;&#x5927; B &#x7EC6;&#x80DE;&#x6DCB;&#x5DF4;&#x7624; &#xFF08;DLBCL&#xFF09; &#x5404;&#x79CD;&#x975E;&#x970D;&#x5947;&#x91D1;&#x6DCB;&#x5DF4;&#x7624;&#x5DF2;&#x5E7F;&#x6CDB;&#x7814;&#x7A76;&#x5F02;&#x5E38;&#x9655;&#x897F;&#x795E;&#x6728; (aSHM) &#x7684;&#x4F5C;&#x7528;&#x3002;&#x867D;&#x7136;&#x4E00;&#x76F4;&#x731C;&#x6D4B; aSHM &#x76EE;&#x6807;&#x8303;&#x56F4;&#x5E7F;&#x6CDB;&#x7684;&#x57FA;&#x56E0;&#x7EC4;&#x57FA;&#x56E0;&#x8FC4;&#x4ECA;&#x53EA;&#x6709;&#x5341;&#x4E8C;&#x4E2A;&#x57FA;&#x56E0;&#x5DF2;&#x88AB;&#x786E;&#x5B9A;&#x4E3A;&#x76EE;&#x6807;&#x7684; aSHM &#x901A;&#x8FC7;&#x6709;&#x9488;&#x5BF9;&#x6027;&#x9009;&#x57FA;&#x56E0;&#x6D4B;&#x5E8F;&#x3002;&#x5168;&#x57FA;&#x56E0;&#x7EC4;&#x7814;&#x7A76;&#x65E8;&#x5728;&#x627E;&#x51FA;&#x4E00;&#x5957;&#x5168;&#x9762;&#x7684; aSHM DLBCL &#x4E2D;&#x53CD;&#x590D;&#x53D1;&#x751F;&#x5C1A;&#x672A;&#x4EE5;&#x524D;&#x8FDB;&#x884C;&#x7684;&#x76EE;&#x6807;&#x3002;&#x5728;&#x8FD9;&#x91CC;&#xFF0C;&#x6211;&#x4EEC;&#x76EE;&#x524D; DLBCL &#x786E;&#x5B9A;&#x901A;&#x8FC7;&#x5206;&#x6790;&#x57FA;&#x56E0;&#x7EC4;&#x548C;&#x8F6C;&#x5F55;&#x7EC4;&#x6570;&#x636E;&#x6765;&#x81EA; 40 DLBCL &#x60A3;&#x8005;&#x7684;&#x4F53;&#x7EC6;&#x80DE; hypermutated &#x57FA;&#x56E0;&#x7684;&#x5168;&#x9762;&#x8BC4;&#x4F30;&#x3002;&#x6211;&#x4EEC;&#x7684;&#x5206;&#x6790;&#x9A8C;&#x8BC1;&#x6709;&#x53D7; aSHM &#x6B83;&#x53CA;&#x7684;&#x786E;&#x5B9E;&#x8BB8;&#x591A;&#x57FA;&#x56E0;&#x3002;&#x5C24;&#x5176;&#x662F;&#xFF0C;&#x6211;&#x4EEC;&#x5DF2;&#x786E;&#x5B9A;&#x663E;&#x793A; aSHM &#x6D3B;&#x52A8;&#x6BD4;&#x4EE5;&#x524D;&#x62A5;&#x544A;&#x7684;&#x57FA;&#x56E0;&#x76F8;&#x540C;&#x6216;&#x66F4;&#x9AD8;&#x6C34;&#x5E73;&#x7684; 32 &#x79CD;&#x65B0;&#x76EE;&#x6807;&#x3002;&#x8FD9;&#x4E9B;&#x65B0;&#x578B;&#x7684;&#x76EE;&#x6807;&#xFF0C;&#x5F53;&#x4E2D; 22 &#x57FA;&#x56E0;&#x663E;&#x793A; mRNA &#x4E30;&#x5EA6;&#x548C; aSHM &#x4E4B;&#x95F4;&#x660E;&#x663E;&#x7684;&#x76F8;&#x5173;&#x6027;&#x3002;

&#x6DCB;&#x5DF4;&#x7624;&#x8D85;&#x5F02;&#x5E38;&#x7684;&#x4F53;&#x7EC6;&#x80DE;&#x53D8;&#x5F02;&#x7684;&#x590D;&#x53D1;&#x6027;&#x76EE;&#x6807;&#x3002;

Somatic hypermutation (SHM) in the variable region of immunoglobulin genes (IGV) naturally occurs in a narrow window of B cell development to provide high-affinity antibodies. However, SHM can also aberrantly target proto-oncogenes and cause genome instability. The role of aberrant SHM (aSHM) has been widely studied in various non-Hodgkin's lymphoma particularly in diffuse large B-cell lymphoma (DLBCL). Although, it has been speculated that aSHM targets a wide range of genome loci so far only twelve genes have been identified as targets of aSHM through the targeted sequencing of selected genes. A genome-wide study aiming at identifying a comprehensive set of aSHM targets recurrently occurring in DLBCL has not been previously undertaken. Here, we present a comprehensive assessment of the somatic hypermutated genes in DLBCL identified through an analysis of genomic and transcriptome data derived from 40 DLBCL patients. Our analysis verifies that there are indeed many genes that are recurrently affected by aSHM. In particular, we have identified 32 novel targets that show same or higher level of aSHM activity than genes previously reported. Amongst these novel targets, 22 genes showed a significant correlation between mRNA abundance and aSHM.

Recurrent targets of aberrant somatic hypermutation in lymphoma.

L&#39;hypermutation somatique (SHM) dans la r&eacute;gion variable des g&egrave;nes des immunoglobulines (IGV) se produit naturellement dans une &eacute;troite fen&ecirc;tre de d&eacute;veloppement des cellules de B de fournir des anticorps de haute affinit&eacute;. Cependant, SHM peut &eacute;galement de mani&egrave;re aberrante ciblent les proto-oncog&egrave;nes et provoquer l&#39;instabilit&eacute; du g&eacute;nome. Le r&ocirc;le de SHM aberrant (5&egrave;me) a &eacute;t&eacute; largement &eacute;tudi&eacute; dans diverses lymphome non hodgkinien-particuli&egrave;rement en lymphome diffus de B-cellule grand (LMNH). M&ecirc;me si, il a &eacute;t&eacute; sp&eacute;cul&eacute; qu&#39;aSHM cibles un large &eacute;ventail de g&egrave;nes jusqu&#39;ici seulement douze locus de g&eacute;nome ont &eacute;t&eacute; identifi&eacute;s comme cibles de 5&egrave;me par le s&eacute;quen&ccedil;age cibl&eacute; de certains g&egrave;nes. Une &eacute;tude G&eacute;nome-large visant &agrave; identifier un ensemble complet de cibles aSHM r&eacute;currente chez les LMNH pas d&eacute;j&agrave; engag&eacute;e. Nous pr&eacute;sentons ici une &eacute;valuation d&eacute;taill&eacute;e des g&egrave;nes hypermutated somatique chez LMNH identifi&eacute;s par une analyse du g&eacute;nome et donn&eacute;es de transcriptome provenant de 40 patients de LMNH. Notre analyse v&eacute;rifie qu&#39;il existe en effet plusieurs g&egrave;nes qui sont affect&eacute;s de fa&ccedil;on r&eacute;currente par aSHM. En particulier, nous avons identifi&eacute; 32 nouvelles cibles qui montrent le niveau identique ou plus &eacute;lev&eacute; d&#39;activit&eacute; aSHM que g&egrave;nes pr&eacute;c&eacute;demment signal&eacute;es. Parmi ces nouvelles cibles, 22 g&egrave;nes ont montr&eacute; une corr&eacute;lation significative entre l&#39;abondance de l&#39;ARNm et aSHM.

Cibles r&eacute;currentes d&#39;aberrante hypermutation somatique des lymphomes.

Somatische Hypermutation (SHM) in die Variable Region der Immunglobulin-Gene (IGV) kommt in der Natur in einem engen Zeitfenster von B-Zell-Entwicklung hoher Affinit&auml;t Antik&ouml;rper bereitstellen. SHM kann jedoch auch abnorm deiner Proto-oncogenes und Genom Instabilit&auml;t verursachen. Die Rolle der abweichenden SHM (aSHM) wurde weithin in verschiedenen non-Hodgkin Lymphome insbesondere bei diffusen gro&szlig;en B-Zell-Lymphom (DLBCL) untersucht. Obwohl es spekuliert hat, dass aSHM Ziele eine Vielzahl von Genom-Loci bisher nur zw&ouml;lf Gene haben worden als Ziel von aSHM durch die gezielte Sequenzierung des ausgew&auml;hlten Gene identifiziert. Eine genomweiten-Studie abzielen, identifizieren einen umfassenden Satz von aSHM Ziele, die Mindestlaufzeit in DLBCL auftritt nicht zuvor durchgef&uuml;hrt wurde. Hier pr&auml;sentieren wir eine umfassende Bewertung der somatischen Hypermutated Gene in DLBCL identifiziert durch eine Analyse der genomischen und Transkriptom-Daten von 40 DLBCL-Patienten abgeleitet. Unsere Analyse &uuml;berpr&uuml;ft, ob es gibt tats&auml;chlich viele Gene, die Mindestlaufzeit von aSHM betroffen sind. Insbesondere haben wir 32 neuartige Ziele identifiziert, die gleiche oder eine h&ouml;here Ebene der aSHM Aktivit&auml;t als Gene zuvor gemeldet zu zeigen. Unter dieser neuartigen Ziele zeigte 22 Gene eine signifikante Korrelation zwischen mRNA-F&uuml;lle und aSHM.

Wiederkehrende Ziele von aberrant somatische Hypermutation beim Lymphom.

Ipermutazione somatica (SHM) nella regione variabile di geni per l&#39;immunoglobulina (IGV) si verifica naturalmente in una stretta finestra di sviluppo delle cellule di B di fornire anticorpi ad alta affinit&agrave;. Tuttavia, SHM pu&ograve; anche modo anomalo target proto-oncogeni e provocare l&#39;instabilit&agrave; del genoma. Il ruolo di aberrant SHM (aSHM) &egrave; stata ampiamente studiato in vari linfoma non Hodgkin-specialmente nel grande linfoma a cellule B diffuso (DLBCL). Anche se, &egrave; stato ipotizzato che gli obiettivi aSHM una vasta gamma di geni finora soltanto dodici di loci del genoma hanno stati identificati come obiettivi di aSHM attraverso il sequenziamento dei geni selezionati mirato. Uno studio genome-wide che mira a individuare un set completo di obiettivi aSHM periodica che si verificano in DLBCL &egrave; non stato precedentemente intrapreso. Presentiamo qui, una valutazione globale dei geni hypermutated somatico in DLBCL identificati attraverso un&#39;analisi di genomica e transcriptome dati derivati da 40 pazienti con DLBCL. La nostra analisi verifica che non ci sono infatti molti geni che sono ripetutamente colpiti da aSHM. In particolare, abbiamo identificato 32 nuovi bersagli che mostrano un livello uguale o superiore di aSHM attivit&agrave; di geni precedentemente segnalato. Tra questi nuovi bersagli, 22 geni hanno mostrato una significativa correlazione tra abbondanza di mRNA e aSHM.

Obiettivi ricorrenti di ipermutazione somatica aberrante nel linfoma.

&#x4F53;&#x7D30;&#x80DE;&#x8D85;&#x5909;&#x7570; (SHM) &#x514D;&#x75AB;&#x30B0;&#x30ED;&#x30D6;&#x30EA;&#x30F3;&#x907A;&#x4F1D;&#x5B50; (IGV) &#x306E;&#x53EF;&#x5909;&#x9818;&#x57DF;&#x3067;&#x306F;&#x5F53;&#x7136;&#x306E;&#x3053;&#x3068;&#x306A;&#x304C;&#x3089;&#x9AD8;&#x89AA;&#x548C;&#x6027;&#x6297;&#x4F53;&#x3092;&#x63D0;&#x4F9B;&#x3059;&#x308B; B &#x7D30;&#x80DE;&#x306E;&#x767A;&#x9054;&#x306E;&#x72ED;&#x3044;&#x30A6;&#x30A3;&#x30F3;&#x30C9;&#x30A6;&#x3067;&#x767A;&#x751F;&#x3057;&#x307E;&#x3059;&#x3002;&#x305F;&#x3060;&#x3057;&#x3001;SHM &#x3067;&#x304D;&#x307E;&#x3059;&#x3082;&#x7570;&#x5E38;&#x306E;&#x30D7;&#x30ED;&#x30C8;&#x30AA;&#x30F3;&#x30B3;&#x30B8;&#x30FC;&#x30F3;&#x306E;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x3057;&#x3001;&#x30B2;&#x30CE;&#x30E0;&#x4E0D;&#x5B89;&#x5B9A;&#x6027;&#x3092;&#x5F15;&#x304D;&#x8D77;&#x3053;&#x3057;&#x307E;&#x3059;&#x3002;&#x7570;&#x5E38;&#x306A; SHM &#xFF08;aSHM&#xFF09; &#x306E;&#x5F79;&#x5272;&#x306F;&#x3001;&#x7279;&#x306B;&#x3073;&#x307E;&#x3093;&#x6027;&#x5927;&#x578B; B &#x7D30;&#x80DE;&#x6027;&#x30EA;&#x30F3;&#x30D1;&#x816B; &#xFF08;DLBCL&#xFF09; &#x306E;&#x69D8;&#x3005; &#x306A;&#x975E;&#x30DB;&#x30B8;&#x30AD;&#x30F3; &#x30EA;&#x30F3;&#x30D1;&#x816B;&#x3067;&#x5E83;&#x304F;&#x7814;&#x7A76;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;ASHM &#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8; &#x30B2;&#x30CE;&#x30E0;&#x907A;&#x4F1D;&#x5B50;&#x5EA7;&#x306E;&#x3053;&#x308C;&#x307E;&#x3067;&#x306E;&#x3068;&#x3053;&#x308D;&#x308F;&#x305A;&#x304B; 12 &#x907A;&#x4F1D;&#x5B50;&#x306E;&#x5E83;&#x3044;&#x7BC4;&#x56F2;&#x3092;&#x6301;&#x3063;&#x3066;&#x3044;&#x308B;&#x3053;&#x3068;&#x304C;&#x63A8;&#x6E2C;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x304C;&#x3001;&#x9078;&#x629E;&#x3057;&#x305F;&#x907A;&#x4F1D;&#x5B50;&#x306E;&#x5BFE;&#x8C61;&#x3068;&#x306A;&#x308B;&#x30B7;&#x30FC;&#x30B1;&#x30F3;&#x30B9;&#x3092;&#x901A;&#x3058;&#x3066; aSHM &#x306E;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x3068;&#x3057;&#x3066;&#x78BA;&#x8A8D;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;&#x5305;&#x62EC;&#x7684;&#x306A;&#x30BB;&#x30C3;&#x30C8;&#x306E;&#x53CD;&#x5FA9;&#x7684;&#x3067; DLBCL &#x304C;&#x767A;&#x751F;&#x3057;&#x3066;&#x4EE5;&#x524D;&#x5F15;&#x304D;&#x53D7;&#x3051;&#x3089;&#x308C;&#x3066;&#x3044;&#x306A;&#x3044; aSHM &#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x306E;&#x8B58;&#x5225;&#x3092;&#x3081;&#x3056;&#x3057;&#x3066;&#x30B2;&#x30CE;&#x30E0;&#x7814;&#x7A76;&#x3002;&#x3053;&#x3053;&#x3067;&#x306F;&#x3001;&#x30B2;&#x30CE;&#x30E0;&#x306E;&#x5206;&#x6790;&#x3092;&#x4ECB;&#x3057;&#x3066;&#x8B58;&#x5225; DLBCL &#x3068; 40 DLBCL &#x60A3;&#x8005;&#x304B;&#x3089;&#x6D3E;&#x751F;&#x3057;&#x305F;&#x30C8;&#x30E9;&#x30F3;&#x30B9;&#x30AF;&#x30EA;&#x30D7;&#x30C8;&#x30FC;&#x30E0; &#x30C7;&#x30FC;&#x30BF;&#x306B;&#x304A;&#x3051;&#x308B;&#x4F53;&#x6027; hypermutated &#x907A;&#x4F1D;&#x5B50;&#x306E;&#x5305;&#x62EC;&#x7684;&#x306A;&#x8A55;&#x4FA1;&#x3092;&#x63D0;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x6211;&#x3005; &#x306E;&#x5206;&#x6790;&#x3067;&#x306F;&#x3001;&#x53CD;&#x5FA9;&#x7684; aSHM &#x306B;&#x3088;&#x3063;&#x3066;&#x5F71;&#x97FF;&#x3092;&#x53D7;&#x3051;&#x308B;&#x78BA;&#x304B;&#x306B;&#x591A;&#x304F;&#x306E;&#x907A;&#x4F1D;&#x5B50;&#x304C;&#x3042;&#x308B;&#x3053;&#x3068;&#x3092;&#x78BA;&#x8A8D;&#x3057;&#x307E;&#x3059;&#x3002;&#x7279;&#x306B;&#x3001;&#x4EE5;&#x524D;&#x306B;&#x5831;&#x544A;&#x3055;&#x308C;&#x305F;&#x907A;&#x4F1D;&#x5B50;&#x3088;&#x308A; aSHM &#x6D3B;&#x52D5;&#x306E;&#x540C;&#x3058;&#x307E;&#x305F;&#x306F;&#x3088;&#x308A;&#x9AD8;&#x3044;&#x30EC;&#x30D9;&#x30EB;&#x3092;&#x8868;&#x793A;&#x3059;&#x308B; 32 &#x306E;&#x65B0;&#x3057;&#x3044;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x3092;&#x8B58;&#x5225;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x3053;&#x308C;&#x3089;&#x65B0;&#x898F;&#x306E;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x9593;&#x3067; 22 &#x907A;&#x4F1D;&#x5B50; mRNA &#x306E;&#x8C4A;&#x304B;&#x3055;&#x3068; aSHM &#x306E;&#x6709;&#x610F;&#x306A;&#x76F8;&#x95A2;&#x3092;&#x793A;&#x3057;&#x305F;&#x3002;

&#x7570;&#x5E38;&#x306A;&#x4F53;&#x7D30;&#x80DE;&#x8D85;&#x5909;&#x7570;&#x30EA;&#x30F3;&#x30D1;&#x816B;&#x306E;&#x518D;&#x767A;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x3002;

&#xC2E0;&#xCCB4;&#xC801;&#xC778; hypermutation (SHM) &#xBA74;&#xC5ED; &#xAE00;&#xB85C;&#xBD88;&#xB9B0; &#xC720;&#xC804;&#xC790; (IGV)&#xC758; &#xAC00;&#xBCC0; &#xC601;&#xC5ED;&#xC5D0;&#xC11C; &#xB192;&#xC740; &#xC120;&#xD638;&#xB3C4; &#xD56D; &#xCCB4;&#xB97C; &#xC81C;&#xACF5; &#xD558;&#xB294; B &#xC138;&#xD3EC; &#xAC1C;&#xBC1C;&#xC758; &#xC881;&#xC740; &#xCC3D;&#xC5D0;&#xC11C; &#xC790;&#xC5F0;&#xC2A4;&#xB7FD; &#xAC8C; &#xBC1C;&#xC0DD; &#xD569;&#xB2C8;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098; SHM &#xC218; &#xB610;&#xD55C; aberrantly proto-oncogenes &#xB300;&#xC0C1; &#xD558; &#xACE0; &#xAC8C;&#xB188;&#xC744; &#xBD88;&#xC548;&#xC815; &#xD569;&#xB2C8;&#xB2E4;. &#xD0C8; &#xC120; SHM (aSHM)&#xC758; &#xC5ED;&#xD560;&#xC744; &#xB110;&#xB9AC; &#xD655;&#xC0B0; &#xD070; B-&#xC138;&#xD3EC; &#xB9BC;&#xD504; &#xC885; (DLBCL)&#xC5D0;&#xC11C; &#xD2B9;&#xD788; &#xB2E4;&#xC591; &#xD55C; &#xBE44;-Hodgkin&#xC758; &#xB9BC;&#xD504; &#xC885;&#xC5D0;&#xC11C; &#xACF5;&#xBD80; &#xD558;&#xACE0;&#xC788;&#xB2E4;. ASHM &#xB300;&#xC0C1; &#xB2E4;&#xC591; &#xD55C; &#xAC8C;&#xB188; loci&#xB9CC; &#xC9C0;&#xAE08;&#xAE4C;&#xC9C0; 12 &#xAC1C;&#xC758; &#xC720;&#xC804;&#xC790;&#xAC00; &#xCD94;&#xCE21; &#xB418;&#xC5B4; &#xC788;&#xC9C0;&#xB9CC; &#xC120;&#xD0DD; &#xB41C; &#xC720;&#xC804;&#xC790;&#xC758; &#xD0C0;&#xAC9F;&#xB41C; &#xC2DC;&#xD000;&#xC2F1;&#xC744; &#xD1B5;&#xD574; Ashm&#xC758; &#xB300;&#xC0C1;&#xC73C;&#xB85C; &#xD655;&#xC778; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xAC8C;&#xB188; &#xB113;&#xC740; &#xC2DD;&#xBCC4; recurrently DLBCL&#xC5D0;&#xC11C; &#xBC1C;&#xC0DD;&#xC740; &#xD558;&#xC9C0; &#xC774;&#xC804;&#xC5D0; &#xC2DC;&#xD589; &#xB41C; aSHM &#xB300;&#xC0C1;&#xC758; &#xC885;&#xD569; &#xC138;&#xD2B8;&#xB97C; &#xBAA9;&#xD45C;&#xB85C; &#xACF5;&#xBD80; &#xD569;&#xB2C8;&#xB2E4;. &#xC5EC;&#xAE30;, &#xC120;&#xBB3C;&#xC774; DLBCL&#xC758; &#xAC8C;&#xB188; &#xBD84;&#xC11D;&#xC744; &#xD1B5;&#xD574; &#xC2DD;&#xBCC4; &#xBC0F; transcriptome &#xB370;&#xC774;&#xD130; 40 DLBCL &#xD658;&#xC790;&#xC5D0; &#xAC8C; &#xC11C; &#xD30C;&#xC0DD; &#xB41C; &#xCCB4;&#xC138;&#xD3EC; hypermutated &#xC720;&#xC804;&#xC790;&#xC758; &#xD3EC;&#xAD04;&#xC801;&#xC778; &#xD3C9;&#xAC00;. &#xC6B0;&#xB9AC;&#xC758; &#xBD84;&#xC11D; &#xC2E4;&#xC81C;&#xB85C; &#xB9CE;&#xC740; &#xC720;&#xC804;&#xC790; recurrently aSHM &#xC601;&#xD5A5;&#xC744; &#xD655;&#xC778; &#xD569;&#xB2C8;&#xB2E4;. &#xD2B9;&#xD788;, aSHM &#xD65C;&#xB3D9; &#xC774;&#xC804;&#xC5D0; &#xBCF4;&#xACE0; &#xB41C; &#xC720;&#xC804;&#xC790; &#xBCF4;&#xB2E4; &#xAC19;&#xAC70;&#xB098; &#xB354; &#xB192;&#xC740; &#xB808;&#xBCA8;&#xC744; &#xD45C;&#xC2DC; &#xD558;&#xB294; 32 &#xC18C;&#xC124; &#xB300;&#xC0C1; &#xD30C;&#xC545; &#xD588;&#xC2B5;&#xB2C8;&#xB2E4;. &#xC774;&#xB7EC;&#xD55C; &#xC18C;&#xC124; &#xB300;&#xC0C1; &#xC911; 22 &#xC720;&#xC804;&#xC790; mRNA &#xD48D;&#xBD80;&#xC640; aSHM &#xC0AC;&#xC774;&#xC758; &#xC911;&#xC694; &#xD55C; &#xC0C1;&#xAD00; &#xAD00;&#xACC4;&#xB97C; &#xBCF4;&#xC600;&#xB2E4;.

&#xC7AC;&#xBC1C; &#xC131; &#xD0C8; &#xC120; &#xC2E0;&#xCCB4;&#xC801;&#xC778; hypermutation &#xB9BC;&#xD504; &#xC885; &#xB300;&#xC0C1;&#xC785;&#xB2C8;&#xB2E4;.

Hipermutaci&oacute;n som&aacute;tica (SHM) en la regi&oacute;n variable de genes de inmunoglobulina (IGV) ocurre naturalmente en una estrecha ventana de desarrollo de la c&eacute;lula B proporcionar anticuerpos de alta afinidad. Sin embargo, SHM puede tambi&eacute;n aberrantemente objetivo proto-oncogenes y causar inestabilidad gen&oacute;mica. El papel de SHM aberrante (aSHM) ha sido ampliamente estudiado en el linfoma no Hodgkin varios particularmente en linfoma difuso de c&eacute;lulas B grandes (DLBCL). Aunque se ha especulado que objetivos aSHM una amplia gama de genes hasta ahora solamente doce de genoma loci han identificado como objetivos de aSHM a trav&eacute;s de la secuencia espec&iacute;fica de genes seleccionados. Un estudio del genoma con el objetivo de identificar un conjunto amplio de objetivos de aSHM recurrente que ocurre en DLBCL no ha sido previamente realizado. Aqu&iacute;, presentamos una evaluaci&oacute;n exhaustiva de los genes som&aacute;ticos hypermutated en DLBCL identificado mediante un an&aacute;lisis de gen&oacute;mica y transcriptoma datos derivados de 40 pacientes DLBCL. Nuestro an&aacute;lisis comprueba que existen en efecto muchos genes que recurrentemente se ven afectados por aSHM. En particular, se han identificado 32 nuevas dianas que muestran el mismo o mayor nivel de actividad de aSHM que genes previamente registrados. Entre estas nuevas dianas, 22 genes mostraron una correlaci&oacute;n significativa entre la abundancia de ARNm y aSHM.

Objetivos recurrentes de hipermutaci&oacute;n som&aacute;tica aberrante en el linfoma.

Diffuse large B-cell lymphoma (DLBCL) is a genetically heterogeneous cancer composed of at least 2 molecular subtypes that differ in gene expression and distribution of mutations. Recently, application of genome/exome sequencing and RNA-seq to DLBCL has revealed numerous genes that are recurrent targets of somatic point mutation in this disease. Here we provide a whole-genome-sequencing-based perspective of DLBCL mutational complexity by characterizing 40 de novo DLBCL cases and 13 DLBCL cell lines and combining these data with DNA copy number analysis and RNA-seq from an extended cohort of 96 cases. Our analysis identified widespread genomic rearrangements including evidence for chromothripsis as well as the presence of known and novel fusion transcripts. We uncovered new gene targets of recurrent somatic point mutations and genes that are targeted by focal somatic deletions in this disease. We highlight the recurrence of germinal center B-cell-restricted mutations affecting genes that encode the S1P receptor and 2 small GTPases (GNA13 and GNAI2) that together converge on regulation of B-cell homing. We further analyzed our data to approximate the relative temporal order in which some recurrent mutations were acquired and demonstrate that ongoing acquisition of mutations and intratumoral clonal heterogeneity are common features of DLBCL. This study further improves our understanding of the processes and pathways involved in lymphomagenesis, and some of the pathways mutated here may indicate new avenues for therapeutic intervention.

Mutational and structural analysis of diffuse large B-cell lymphoma using whole-genome sequencing.

Antigen receptor signalling activates the canonical NF-κB pathway via the CARD11/BCL10/MALT1 (CBM) signalosome involving key, yet ill-defined roles for linear ubiquitination. The paracaspase MALT1 cleaves and removes negative checkpoint proteins, amplifying lymphocyte responses in NF-κB activation and in B-cell lymphoma subtypes. To identify new human MALT1 substrates, we compare B cells from the only known living MALT1(mut/mut) patient with healthy MALT1(+/mut) family members using 10-plex Tandem Mass Tag TAILS N-terminal peptide proteomics. We identify HOIL1 of the linear ubiquitin chain assembly complex as a novel MALT1 substrate. We show linear ubiquitination at B-cell receptor microclusters and signalosomes. Late in the NF-κB activation cycle HOIL1 cleavage transiently reduces linear ubiquitination, including of NEMO and RIP1, dampening NF-κB activation and preventing reactivation. By regulating linear ubiquitination, MALT1 is both a positive and negative pleiotropic regulator of the human canonical NF-κB pathway-first promoting activation via the CBM--then triggering HOIL1-dependent negative-feedback termination, preventing reactivation.

The paracaspase MALT1 cleaves HOIL1 reducing linear ubiquitination by LUBAC to dampen lymphocyte NF-κB signalling.

In vivo, B cells are often activated by antigens that are displayed on the surface of antigen-presenting cells (APCs). Binding of membrane-associated antigens to the B cell receptor (BCR) causes rapid cytoskeleton-dependent changes in the spatial organization of the BCR and other B cell membrane proteins, leading to the formation of an immune synapse. This process has been modeled using antigens attached to artificial planar lipid bilayers or to plasma membrane sheets. As a more physiological system for studying B cell-APC interactions, we have expressed model antigens in easily transfected adherent cell lines such as Cos-7 cells. The model antigens that we have used are a transmembrane form of a single-chain anti-Igκ antibody and a transmembrane form of hen egg lysozyme that is fused to a fluorescent protein. This has allowed us to study multiple aspects of B cell immune synapse formation including cytoskeletal reorganization, BCR microcluster coalescence, BCR-mediated antigen gathering, and BCR signaling. Here, we provide protocols for expressing these model antigens on the surface of Cos-7 cells, transfecting B cells with siRNAs or with plasmids encoding fluorescent proteins, using fixed cell and live cell fluorescence microscopy to image B cell-APC interactions, and quantifying APC-induced changes in BCR spatial organization and signaling.

Madison Bolger-Munro

Department of Microbiology and Immunology

University of British Columbia

Visualizing the Actin and Microtubule Cytoskeletons at the B-cell Immune Synapse Using Stimulated Emission Depletion (STED) Microscopy

Madison Bolger-Munro

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Microbiology and Immunology

University of British Columbia

Visualizing the Actin and Microtubule Cytoskeletons at the B-cell Immune Synapse Using Stimulated Emission Depletion (STED) Microscopy

Department of Microbiology and Immunology