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Transport proteins, cell adhesion factors, stabilizers and detoxifiers, it is heat inactivated in a bath thermostated at 56 ° Celsius for 30 minutes in order to destroy complement molecules and immunoglobulins. The complement reaction cascade leads to cell lysis, and therefore to the death of the culture. With the pipette, which is another system for transferring liquids from one container to another, phytohaemagglutinin is added which is a lectin extracted from the bean. The phytohaemagglutinin has two different types of subunits: L, responsible for the mitogenic properties, reactive with the lymphocytes and E capable of agglutinating the erythrocytes. Finally, we add the antibiotics, those used routinely, are: penicillin, strepto-mycin. Broad spectrum antibiotics. Added all the components to obtain the complete medium, 4.7 milliliters are dispensed into each sterilized culture tube and 300 microliters of whole blood are added. The safety cabinet is turned off, closed and a UV radiation cycle at 260 nanometers is carried out for at least 1 hour. The tubes are placed in an incubator thermostated at 37 ° Celsius, because ours are human cells. Cells can survive mild hypothermia compared to the optimal temperature, but mild hyperthermia leads to death or changes. The tubes are placed on a rotating plate to mimic blood flow. At the seventieth hour 50 microliters of Colcemid are added ,it is a synthetic alkaloid derived from colchicine, extracted from Colchicum autumnale. It is used to stop cells in metaphase. It prevents the formation of the spindle during mitosis, depolymerizing the microtubules, thus causing halt in the half-phase. We continue to work under a biological safety cabinet so as not to contaminate the crops, at this moment the cells are still alive. The hypotonic potassium chloride zero point zero seventy five molar solution to be used in the collection phase is prepared by weighing two comma eight grams of K Cl to which 500 milliliters of deionized water are added. It is then placed at 37 ° Celsius to avoid a thermal shock to the cells when it is added. Subsequently, the culture is stopped, the cells, after 72 hours in culture, are collected by centrifugation (and the supernatant is discarded). The laboratory centrifuge is an instrument that is used to separate two bodies with different densities through the use of centrifugal acceleration. This process is called centrifugation and is based on the sedimentation phenomenon of a high density solid body mixed with a lower density fluid. Centrifugation increases the gravitational acceleration applied to the suspension under consideration by replacing it with the centrifugal force, that is, a specific force that acts on a body that moves with circular motion. It is always necessary to balance the tubes, that is, the weight of two samples in a diametrically opposed position must be identical. Finally, the centrifuge is set at 2100 repetitions per minute for 5 minutes and is started. Once centrifugation is complete, the tubes must be carefully removed from the housings to avoid mixing the newly separated mixture again. The supernatant is eliminated with an automatic vacuum aspirator or also with a plastic pasteur pipette equipped with a teat. The pellet is well resuspended by tapping the bottom of the tube. Subsequently, the hypotonic solution is added drop by drop, continuously resuspending to prevent the red blood cells from agglutinating by trapping the lymphocytes. The hypotonic solution is used to create an environment with a lower salt concentration than the cytoplasmic one that allows water to enter the cells according to a concentration gradient, the red blood cells burst, the lymphocytes swell and the chromosomes all the interior of the highly stretched and thinned cytoplasmic membrane are suspended. The tubes are heated to 37 ° Celsius for 15 minutes to facilitate this process. Subsequently the samples are taken and the blocking phase continues. The prefix (prepared from methanol: acetic acid in a 3 to 5 ratio) is prepared and added to make the cells, very fragile at this moment, more resistant to subsequent centrifugation, adding them. At this stage the cells are still alive. From the moment the prefix, containing methanol and acetic acid, is used, it is necessary to work under a chemical safety cabinet, also called a suction safety cabinet. Chemical safety cabinets are the main collective protection devices for the protection of the health of operators from the risk deriving from the use and handling of dangerous chemical agents. And they aim to reduce the environmental concentration of dusts, fumes, gases and vapors of toxic substances that can be generated during the activities carried out in scientific research and teaching laboratories The efficiency of the chemical safety cabinet must be verified both at the time of the first installation and over time with periodic checks.