Cultivation of cells and tissues in vitro, significance in medicine

Culture for cytogenetic examination[edit | edit source]

chromosomal examination is possible only with full spiralization of chromosomes and after appropriate processing of bb.
therefore, direct processing is only possible for cells from tissues with high mitotic activity (bone marrow, tumor, chorionic villi), but for most other cells, cultivation is necessary
the mitotic index is used to determine whether tissue cell culture is necessary and for how long
mitotic index = bb in mitosis/all tissue bb * 100 (%)
examination of chromosomes in meiosis is not performed as a standard (the exception is the examination of sperm and eggs for the purposes of assisted reproduction)

cultivation can be short-term (e.g., peripheral blood cells - 72 hours) or long-term (weeks)
cultured in vials or tubes with culture medium supplemented with serum with growth factors
the temperature during cultivation is 37 °C, the pH must be constant, for long-term cultures 5% CO2 in the thermostat atmosphere is also important
tissue cells are mechanically or enzymatically loosened before cultivation

for postnatal examination, mostly peripheral blood lymphocytes are cultured after the addition of the mitogen phytohemagglutinin
cells from amniotic fluid (amniocentesis – 16 to 18 weeks of gestation), trophoblast cells (trophoblast biopsy 11 to 12 weeks) or lymphocytes from fetal blood (cordocentesis – after 20 weeks) are used for prenatal examination

addition of colchicine - destruction of the dividing spindle (colchicine is a poison from ocun, its duration of action is shorter for HRT methods, when cells in prometaphase are used)
action of hypotonic solution 0.075M KCl → loosening of cell contents and individualization of chromosomes
fixation with a mixture of acetic acid and methanol (1:3)
dripping the specimen onto a glass slide + staining (e.g., streaking)