Human lymphocyte culture: intrinsic factors influencing the quality of chromosome preparations.

In a cytogenetic study of the consecutive cell cycles (M1, M2 etc.) from human lymphocyte cultures after 5-bromodeoxyuridine incorporation followed by differential Giemsa staining, the metaphases of M2 and subsequent in vitro divisions have been found to spread better than those of M1 cells, as if the cells of in vitro generation suffer some membrane alterations. Moreover presence of S or G2 phase, leukocytes in a blood sample may result into early proliferation in a PHA stimulated culture system, so that the metaphase yield at 72 h will be larger than otherwise, a sizeable portion of which, being in M2 or subsequent cell cycles, will spread better. Thus such individual or transient intrinsic factors of haematologic state may influence the success of a leukocyte culture and the quality of chromosome preparation.