Growth properties and alloantigenic expression of murine lymphoblastoid cell lines

Murine lymphoblastoid cell lines were evaluated for their expression of Thy-1 and thymus leukemia (TL) differentiation alloantigens. Two culture conditions were shown to affect this expression. Cells grown in fetal bovine serum (FBS)-enriched medium expressed up to 15 times the amount of TL as cells grown in horse serum (HS)-enriched medium. Thy-1 expression was less affected by the type of serum used for culture. The phase of growth when the cells were harvested, was demonstrated to affect the expression of Thy-1. The expression of Thy- 1.2 for one cell line examined, L-251A, during logarithmic growth was threefold greater than cells collected during either lag or stationary growth. When culture conditions were standardized a ranking of the amount of Thy-1 and TL expressed by several cell lines was made. All cell lines, except one, L-1210, expressed Thy-1. There was a 450-fold difference in the expression of Thy-1 between the cell lines evaluated. Seven cell lines expressed TL-1,2,3 with a ninefold difference in the amount of expression. The L-251A cell line was cultured in a 14 liter fermentor for a 26 day period. During this time TL and Thy-1 expression did not vary significantly, demonstrating that lymphoblastoid cell lines can be cultured on a continuous basis and will continue to express their surface alloantigens.