Cultured human lymphocytes proliferate faster in medium lacking fetal calf serum and antibiotics.

When human whole blood was cultured in medium containing neither fetal calf serum nor antibiotics, more peripheral lymphocytes initiated DNA synthesis at about 24 h of culture than did lymphocytes in blood cultured in complete medium. Furthermore, the cells proliferated faster, so that by 48 h in culture approximately 20% of the metaphase cells in medium lacking fetal calf serum and antibiotics were in their second division. Such rapid cell proliferation can affect quantitative studies of chromosome aberrations, which should be observed in their first mitosis in culture, before cell death can cause a diminution in aberration yields. The rapid appearance of second-division metaphases should also be advantageous for the measurement of sister-chromatid exchanges (SCEs), which require two cell divisions for their observation. In contrast to cultures with complete medium, cells grown without fetal calf serum and antibiotics had fewer SCEs in second-division cells that divided later in the culture period.