IVDT_In Vitro Diagnostics Technology

IVD Technology, Spring 2013

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ASSAY DEVELOPMENT sical MHC molecules, CD1 family molecules, present nonpeptidic epitopes such as lipid or glycolipid. Te CD1 family molecules can be classifed into three groups: group 1 (CD1a, CD1b, and CD1c); group 2 (CD1d); and group 3 (CD1e). Interestingly, rabbits express all three groups, whereas mice only express group 2, but not groups 1 and 3. Group 1 molecules mainly present a vast range of lipid antigens to clonally diverse T cells that mediate adaptive immunity. By contrast, group 2 molecules present lipid antigens to natural killer T (NKT) cells.1 Tus, the diference in the presentation of nonpeptidic epitopes between rabbit and mouse may explain why rabbits make better antibodies to lipids or glycolipids than mice in general. Primary and secondary antibody repertoire developments in rabbits possess several unique characteristics2, which also may account for the quality of the antibodies produced. First, unlike human and mouse, rabbit B cell development continues in gutassociated lymphoid tissues (GALT), including the appendix. Tat is where B cell follicles form and extensive B cell expansion occurs in response to intestinal microfora for nonimmunogen-specifc antibody repertoire amplifcation, resulting in a larger naïve antibody library. Te primary high copy number repertoire is developed by somatic diversifcation of Ig genes mainly through gene conversion and, to a lesser extent, somatic hypermutation. Gene conversion—a unique IgG gene diversifcation mechanism for rabbits—is a process involving clusters of nucleotide changes from upstream genes to amplify the diversity of antibody repertoire. Second, B cells in the rabbit GALT are selected by both positive and negative selective events. Te cells that survive the selection process exit to the periphery to participate in further engagement with foreign antigens. Both gene conversion and somatic hypermutation occur in secondary lymphoid tissues such as spleen, lymph nodes, and Peyer's patches for secondary antibody repertoire diversifying and afnity maturation. Indeed, the features of B cell follicle expansion in GALT and the gene conversion mechanism for antibody repertoire diversifcation provide greater rabbit antibody selection. Tird, the rabbit antibody is somewhat simpler than mouse and human antibodies. Rabbit IgG has no subclass because it has only one Cγ gene, and the majority (90 to 95%) of light chains is derived from isotype Cκ1. Only 5% to 10% of total IgG light chains are isotype l. Tese characteristics of rabbit IgG make gene cloning much easier than with mouse or human IgG. Rabbit IgG has extra disulfde bonds in the variable region of the heavy chain; an extra disulfde bond also exists between Vκ and Cκ in commonly used b4 and b5 allotype rabbits. Tese extra disulfde bonds may result in the great stability and long shelf-life of rabbit Introducing micropoc... $BSDMPEJBHOPTUJDTPMVUJPOTJTBEJWJTJPOPG$BSDMPQMD XIJDICSJOHTUPHFUIFSNBOZZFBSTPGFYQFSJFODFJOUIF NBOVGBDUVSFPGEJTQPTBCMFJUFNTGPSUIFIFBMUIDBSF JOEVTUSZ NJDSPFMFDUSPOJDTFYQFSUJTF BOEEFWFMPQNFOUT JONJDSP¿VJEJDT SFBHFOUDIFNJTUSZBOETVSGBDF USFBUNFOUT8IBUJTNJDSPQPD© NJDSPQPDJTBTFMGSFBEJOH EJTQPTBCMF1PJOU0G$BSF EJBHOPTUJDTQMBUGPSNGFBUVSJOH BNFUFSFETBNQMFPGCPEZ¿VJE $-*"XBJWFQPUFOUJBM DPOUSPMMFESFBHFOUMPBEJOH BMPXDPTU¿VJETFOTJOHTZTUFNBOE BOPOCPBSETZTUFNUPEFUFSNJOFBOEEJTQMBZUIFUFTUPVUDPNF NJDSPQPDJTQPUFOUJBMMZEJTSVQUJWFUFDIOPMPHZ BEBQUBCMFUPB XJEFSBOHFPGBTTBZT NJDSPQPDSFNPWFTUIFOFFEGPSBTFQBSBUFJOTUSVNFOUBOE EJTQPTBCMFGPSFWFSZBTTBZUZQF BDMFBS MPXDPTUNBOVGBDUVSJOHSPVUFIBTCFFOJEFOUJ¾FE DETJTPGGFSJOHFYDMVTJWFMJDFOTJOHPQQPSUVOJUJFTJOSFUVSOGPS FYDMVTJWFNBOVGBDUVSJOHSJHIUT DETJTDVSSFOUMZEFWFMPQJOHUISFFEFWJDFGPSNBUTNJDSPQPDMJUF NJDSPQPD$"5BOENJDSPQPDQSP www.carclodiagnosticsolutions.com T: +44 (0)208 685 0500 Visit us at MD&M East, Booth #2707 ivd tech n o lo gy.com magenta cyan yellow black I VD T EC H N O LO G Y | S PR I NG 2 0 1 3 2 3 ES236232_IV1305_023.pgs 04.23.2013 23:41 UBM

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