Monoclonal antibodies probes specific

The development of monoclonal antibody probes specific to human albumin is the subject of this chapter. These antibody probes and the test methods were developed and evaluated for use in forensic science situations. Although these methods work well on soluble extracts of dried blood stains that are several years old, they have not been applied to archaeological material. The successful development of monoclonal antibodies specific to the human albumin molecule suggests that an approach similar to that used for identifying human tissues and blood on forensic evidence could be applied to any species of interest to the archaeologist. 

Nucleic acids can also be biotinylated by nonenzymatic methods with photobiotin, a photoactivatable biotin analog (6), which can be commercially obtained from BRL, Sigma, and other commercial sources I have not compared the suitability of this method of biotin incorporation with that reported here, but expect that the method would be fully acceptable FMC (Rockland, ME) markets an alternate nonradioactive sequence detection kit known as Chemiprobe. The basis of this system is a chemical modification of cytosine residues m the probe DNA. After hybridization, the probe is detected by means of a monoclonal antibody that specifically recognizes the sulfonated DNA. Detection of the bound monoclonal antibody is achieved by means of an alkaline phosphatase-conjugated second antibody. 

Acceptable bridging molecule systems have been developed which have also simplified the utilization of different detection systems. To illustrate this point, a researcher who has developed a unique monoclonal antibody (a primary antibody) in the mouse may select from a variety of commercially available products consisting of different detection systems (e.g. fluorescein, alkaline phosphatase, colloidal gold) attached to an immunoglobulin that will specifically bind to mouse antibodies (a secondary antibody). In this way the researcher may readily obtain and test a number of detection methods for visualizing target-probe interactions without having to directly label the monoclonal antibody probe. For nucleic acid probes, which in themselves are not readily immunodetectable, it is useful to incorporate or attach detectable moieties to the nucleotides. 

Clearly specific antibodies, and particularly monoclonal antibodies, may be very useful in probing the properties of adsorbed proteins. Specific antibodies have been used to probe the structure of antigens in solution 88). Consider the adsorption of a simple protein with a small number of reasonably well-defined epitopes (surface sites with antibody binding activity), as in Fig. 19. Clearly epitopes E and A are not accessible for binding, while B, C, and D would be sterically accessible. One could also envision a conformational change upon adsorption which produces an epitope... 

Fig. 19. Schematic of a protein with five different antigenic sites (epitopes). Each epitope may have one or more specific monoclonal antibodies. A set of such antibodies can be used to probe which epitopes are accessible or not, allowing the investigator to deduce the orientation of the adsorbed protein...

Figure 5. Sensitivity of antigen-trapping assay with monoclonal antibodies HSA-1 and HSA-2. HSA-2 (type B antibody) was coated on the plate, and then human albumin (A) or serum (B) was diluted as indicated and added to the wells. Biotin-conjugated HSA-1 served as the specific probe. The optical density at 410 nm (OD410) was measured after 15 min.

Specificity of HSA-1. Every specimen from a large panel of human serum samples from various races and sexes reacted with monoclonal antibody HSA-1. No human serum was tested that did not react, a fact indicating the absence of genetic variation in the antigenic site detected by the HSA-1 antibody. The HSA-1 monoclonal antibody thus fulfills two essential criteria for an immunological probe for the identification of the species of origin species specificity and intraspecies conservation of the antigenic site. 

The simplest and most reliable means of diagnosis is a wet-mount examination of the vaginal discharge. Trichomoniasis is confirmed if characteristic pear-shaped, flagellating organisms are observed. Newer diagnostic tests such as monoclonal antibody or DNA probe techniques, as well as polymerase chain reaction tests are highly sensitive and specific. 

Immunochemical and molecular methods are useful for detecting specific fungi from air samples. These techniques are finding greater applications as monoclonal antibodies and DNA probes become available for fungi with known health effects. 

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