Bioinformatics and Genomics News and Views » molecule http://stonedscientist.com Life Science - We'll Tell It Like It Is! Wed, 08 Sep 2010 11:11:35 +0000 http://wordpress.org/?v=2.8.4 en hourly 1 Monoclonal antibodies http://stonedscientist.com/2010/02/12/monoclonal-antibodies/ http://stonedscientist.com/2010/02/12/monoclonal-antibodies/#comments Fri, 12 Feb 2010 17:35:26 +0000 Jessica P. http://stonedscientist.com/?p=564 Monoclonal antibodies are important tool in molecular biology, diagnostics and clinical studies. These protein are produced by a single cells isolated from immunized animals. Current protocol requires an immunization of an animal host, for instance rabbit or mouse; then spleen cells are selected in vitro and B cells are isolated. B cells from spleen are fused with tumoral mouse cells of mieloma in order to stabilize and make possible the B lymphocyte culture. Indeed, B cell culture is difficult to set up and maintain.
antibodyThe hybridoma technology allows overcoming these difficulties because of genetic transformation of mieloma cells. Finally, hybridomas are serially diluted and the antibodies are obtained from cell hybridomas cultures derived from a single cell. Which are the advantages of monoclonal antibody in respect with polyclonal ones? Monoclonal antibodies are codified by the same gene and none point mutations are present to generate some difference into antibody population. Thus, the whole population is identical and specifically recognizes one antigen. Cross reactivity is reduced with monoclonal antibodies and the interaction between antigen and antibody is usually more stable. Furthermore, this technique is also really flexible because it’s virtually possible to create antibody versus each antigen, when it’s possible to immunize the host animal. Which are the applications for monoclonal antibody? Monoclonal antibodies are currently used in molecular biology and biochemistry laboratories for imaging, western blotting, immunoprecipitation and so on. A lot of protocols are based on antibody use. In diagnostics, monoclonal antibodies are used in ELISA dosage or in flow cytometric analyses, as well as infection detection or pregnancy diagnosis.

monoclonalClinical applications of monoclonal antibody are prevalently in oncology. In 1997, the first monoclonal antibody was approved for non- Hodgkin lymphoma treatment. Since this year, several antibodies have been optimized against breast cancer, leukaemia, colon cancer and recently lung cancer. Each antibody recognizes a tumoral antigen and specifically kills only the cells (tumoral) that present that molecule. Thus, adverse effects associated with the use of monoclonal antibodies are reduced if compared with traditional drugs. Based on their specificity, antibodies can be used to carry other useful drugs to cells. For instance, an antibody can be conjugated to radioactive compounds to be addressed to cancer cells. Furthermore, other drugs can be carried into the brain, giving the capability of monoclonal antibody to overcome the blood- brain barrier. Parkinson’s disease can be treated with this approach. Improvement of biochemical characteristics of monoclonal antibodies is one challenge for scientists for the next future. Indeed, it’s important to improve the delivery of monoclonal antibody into all districts of human body. The specificity will be a must if clinical or diagnostic applications are planned for the monoclonal antibody. Furthermore, cheaper technology must be optimized to allow large scale production. Research development in this field is really promising.

]]> http://stonedscientist.com/2010/02/12/monoclonal-antibodies/feed/ 2 Novel small molecule inhibitor has immunosuppression properties http://stonedscientist.com/2009/08/30/novel-small-molecule-inhibitor-has-immunosuppression-properties/ http://stonedscientist.com/2009/08/30/novel-small-molecule-inhibitor-has-immunosuppression-properties/#comments Sun, 30 Aug 2009 15:39:12 +0000 Jessica P. http://stonedscientist.com/?p=71 Immunosuppression is one approach to care some autoimmune diseases, such as rheumatoid arthritis. Etarnercept and cortisone are currently used to care these disorders. In Nature Medicine has been recently published a work that describes a novel possible therapy for this kind of disease. Scientists focussed their attention on small molecule inhibitors of immunoproteasome. This cellular compartment has been identified in monocytes and lymphocytes and is specialized in generating MCH I peptides.

bonesThe selective inhibitor of LMP7, a specific protein belonged to immunoproteasome, down-regulated the expression of MCH I complex and reduced the level of some cytokines, for instance IL23, IL6 and TNF. All these molecules are implicated in the autoimmune response in rheumatoid arthritis. The expression of other cytokines were tuned in following inhibitor exposure. The small molecule inhibitor could have pleiotropic effects of various cell types, by ameliorating drug efficacy. In animal models, indeed, this molecules gained better results than Etanercept in TNF blockade and consequently showed faster resolution of symptoms of immune disorders. This study represents a great hope for all people that are affected by rheumatoid arthritis, but a lot of work still to be done before entering in clinical phase.
Reference: Muchamuel, T. et al. Nature Med. 14 Jun 2009
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