Immunological techniques

Immunology uses techniques common to many areas of biology. However, more specific techniques have been developed at the initiative of immunologists and are more particularly used by them.
A flow cytometer
It is the case of Flow cytometry, a method that allows to analyze multiple parameters at the single cell level. The basis for this method is illustrated here.
It is a technique that uses a very sophisticated equipment that can differentiate among cells looking otherwise very similar cells and also helps undertsand how theses cells fight against microbes. It is based on the phenomenon of fluorecsence (light scattering, fluorescence emission) that vary with the size and content of the cells. In addition, it also uses molecular tools, which are antibodies (yes, the same produced by our immune system) to which a fluorescent molecule was attached. Antibodies have the ability to lock onto a target molecule and to recognize highly selectively molecular targets found on certain cells only. Pretty much like "missiles", these antibodies will be guided to the cells, will lock on them and send the light signal which allow their identification by the cytometer. This technique has revolutionized the knowledge in immunology!

A mas-cytometer
For sure, flow cytometry will soon be replaced by
Mass cytometry also uses antibodies but, in this case, antibodies are not attached to fluorescent molecules but to chemical elements present in nature, which are then detected by a mass spectrometer (a device that detects molecules by their mass). There are two advantages of this method over flow cytometry. First, many more of these elements are available as compared with fluorochromes. Second, these elements can be easily combined whereas sometimes fluorochromes having close fluorescent properties can not be easily identified separately. Therefore,  when flow cytometry was limited to the simultaneous detection of several parameters (typically less than 10), the mass cytometry can analyze tens. The information on a per cell basis is much more complete!

The result of an ELISA
A famous technique will a beautiful female firstname is ELISA. It uses antibodies to semi-quantitatively measure the presence of molecules in biological fluids. Diverse molecules can be detected by this method very much employed in both research and medical laboratory. For instance, cytokines produced during immune responses can be measured by this method. In addition it can also be used a s a diagnostic test to check whether you are infected or not with a given pathogen or detect traces of antigens testifying of your antibody response against this pathogen.

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