Fig. 1.
Identification of hprt−T-lymphocyte clones.
PBMCs were isolated and cloned at 1 to 2 × 104cells/well in the presence of 6-thioguanine (6-TG). Individual wells were scored after 14 to 16 days. (A) A negative clone with no growth in the presence of 6-TG, and only residual feeder cells observed. (B) A positive hprt− mutant clone that grew in the presence of 6-TG, with clusters of growing cells.
