Unformatted text preview: Applications of Monoclonal Antibodies
By: Chris Phelps ETSU Spring 2007 Tick hemolymph cells infected with R. rickettsii. From the CDC. Epidemic Typhus Caused by the bacillus Ricketsia prowazekii (gram ). Obligate intracellular pathogen. Transmitted by the human body louse. The bacteria grows in the louse's gut and is excreted in feces. Portal of entry is pushing louse feces into broken skin while scratching the bite. Usually occurs in areas of crowding, poverty, and bad sanitation. Caused 3 million deaths in each World War. Symptoms:
Fever Severe Headache Rash Nausea Vomiting Virulence Factors R. prowazekii is one of most virulent. Intracellular growth Membrane Lipid peroxidation Actin polymerization Induction of phagocytosis Avoidance of phagosome Prevention:
Animal control Insect control Practice good hygiene Avoid sharing clothes or bedding Treatment:
Doxycycline Chloramphenicol Washing all linens person comes in contact with in hot water (130 F). Hot shower and bathing with anti louse shampoo. Detection of Rickettsia prowazeki in Body Lice and Their Feces by Using Monoclonal Antibodies
Rong Fang, Linda Houhamdi, and Didier Raoult Unite des Rickettsies Faculty Medicine 13385 Marseille, France Serological Assays
Immunofluorescence WeilFelix test Latex agglutination Dot blot assay Slide immunoperoxidase assay Western Blotting Since the two typhus species crossreact, differentiation is difficult serologically. The problem with current diagnosis of typhus is economics. To solve this: Monoclonal Antibodies Monoclonal Antibodies A clone of one specific antibody. Produced by ONE immune cell. Can be created to identify nearly any substance. 1.) Challenge animal immune system 2.) Remove Bcells from spleen or lymph nodes 3.) Create hybridomas 4.) Series of dilutions 5.) Harvest http://users.rcn.com/jkimball.ma.ultranet/Biology Pages/M/Monoclonals.html Experimental Procedure: Purify antigen from R. prowazekii. Produce monoclonal antibodies. Use immunofluorescence assay to select for specific antibodies. Identify the specificity of the antibody. Results: 254 viable hybridoma clones > 187 clones > 40 selected for subcloning > 29 monoclonal antibodies selected 14 recognized the 120 kDa protein (IgG2b & IgG3 subclasses) 15 recognized LPSL (LPSlike antigen). 8 MAbs reacted only with R. prowazekii. Results cont'd: MAb P11A12 was the antibody selected to react with a 120 kDa protein on R. prowazekii. "This report describes a specific, convenient, and reliable diagnostic assay with a sensitivity of 91%. It especially appears to be of practical value when it is required to identify R. prowazekii in lice in a given area, when typhus cases are suspected, or for epidemiological surveys of lice."
Journal of Clinical Microbiology, Sept. 2002, p. 33583363 (a) Feces from an uninfected louse (b) feces of an experimentally infected louse c) cell smear prepared from intestines of an experimentally infected louse References:
http://www.lcusd.net/lchs/mewoldsen/typhus.html http://microbewiki.kenyon.edu/index.php/Rickettsia http://www.cehs.siu.edu/fix/medmicro/ricke.htm http://medinfo.ufl.edu/year2/mmid/bms5300/bugs/ricktyph.html http://textbookofbacteriology.net/Rickettsia.html http://en.wikipedia.org/wiki/Monoclonal_antibody http://jcm.asm.org/cgi/content/full/40/9/3358?view=long&pmid=1 ...
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