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In humans, in most cytogenetic diagnostic procedures, such as karyotype analysis, lymphocyte cultures are used. they are cheap, short-lived and easy to perform. In order to set up a cell culture of lymphocytes, you need: Cells, sterilized material, complete cell culture medium and a thermal incubator at 37°Celsius. Performing a venous blood sampling is certainly one of the most common preanalytical practices. When performing a venous sampling, it is necessary to have a syringe with a disposable sterilized needle (or a butterfly needle). important is the choice of the sampling point and the correct procedure to be performed before and after blood sampling. Gloves are worn, the vein to be pricked is chosen, preferring the cubital one and the area is cleaned with disinfectant. After the puncture, the necessary blood is taken and finally transferred to a test tube with lithium-heparin, an anticoagulant to prevent the collected blood from clotting. This is a biological safety cabinet also called laminar flow safety cabinet, it is a Collective Protection Device with the function of reducing the risk of contaminating the biological sample, and at the same time, to protect the operator when handling dangerous or potentially microorganisms dangerous. This is a class 2 biological safety cabinet, it is equipped with an upper motor fan that pushes the air through HEPA filters creating a vertical laminar flow, when it is turned on it generates the flow but it takes about ten minutes to stabilize it (typically it is 0 point 5 meters per second). The indicator lights from red turn first orange and finally green when it is stable. The contaminants are dragged away from the work area by the air threads made sterilized by the passage through filters. This safety cabinet is suitable for the manipulation of second and third group microorganisms. In addition, sterilized material should be used to avoid contamination. Sterilization is a process whose purpose is to establish aseptic conditions by removing all microorganisms. Sterilization techniques are not difficult, but require a lot of care. The tips, for example, are sold housed in boxes and sterilized with moist heat in an autoclave. A sterilization indicator is applied to them, that is an adhesive tape of white color which turns brown after 20 minutes at 121 ° Celsius, and that means that sterilization has taken place. The biocidal action of heat derives from the oxidation of cellular constituents with irreversible denaturation of enzymes and protein structures. The sensitivity to heat varies in relation to their content in water, the higher it is, the more sensitive the microorganisms are to heat. Sterilization with dry heat is obtained in stoves such as the Pasteur oven (dry stove), by means of hot air obtained with suitable heat generators; the temperature is set at 170 ° Celsius for 1 or 2 hours. The autoclave is the most effective machine for performing hot sterilization, consisting of a steel chamber, a basket for allocating the material to be sterilized, a resistance, and a valve for the escape of air. The chamber will be hermetically sealed and under pressure of 1 atmosphere and inside the steam under pressure will produce temperatures of 121 ° Celsius without the liquids boiling. After sterilization, the changed color of the tape is observed To make the culture medium it is necessary to work under a biological safety cabinet, which is sterilized with 70 ° alcohol. An automatic pipette is used. It is a device which allows the transfer of liquid between different containers. It offers all the flexibility needed to handle very different liquids and measuring applications. The upper button is used to withdraw the liquid, the lower one is used to expel it. It has a filter that is placed inside which is important to keep dry to avoid contamination or blocking of the pipette itself. Serological tips, falcons and tubes with red polystyrene caps, are purchased in sterilized and disposable packs, sterilized by Gamma Rays, on an industrial level. By culture “in vitro” we mean the biotechnological application in which the cells are grown in a sterilized and artificial environment and under controlled chemical-physical conditions. To prepare the complete culture medium for setting up peripheral blood cell cultures, RPMI medium is used, 10% of fetal bovine serum, 1.5% of phytohaemagglutinin and 1% of antibiotics. The soils are basically formed by an isotonic and buffered solution that contains inorganic salts, an energy source such as glucose, the essential amino acids. We use the RPMI 1640 medium with Gluta-max, dipeptide consisting of L-alanine-L-glutamine and hepes, an organic substance used that maintains the physiological pH stable, between pH 7.2 and pH 7.6 and the phenol red, pH indicator.Then the 10% fetal bovine serum is added, it is a complex mixture that contains: Hormonal factors, which stimulate growth, cell proliferation and differentiation.