Haemopoietic lineage sensitivity and individual susceptibility to PCB126: Relation to glutathione S-transferase mu

The effect of PCB126 on the in vitro growth potential of human myeloid (CFU -GM) and erythroid (BFU-E) progenitor cells derived from human cord blood h armopoietic cells was examined. The possible link between individual variab ility in susceptibility and the presence of the xenobiotic metabolizing enz yme glutathione S-transferase class mu (GST mu) was studied. After density centrifugation separation. mononuclear cord blood cells were cultured in th e presence of PCB126 (10(-6) M and 10(-8) M). Several cord blood samples we re simultaneously tested for: (1) colony formation and (2) the presence of the GST mu gene measured by PCR. An interindividual variability in the resp onse to PCB126 was present. At 10(-8) M and 10(-6) M PCB126. respectively 8 (40%) and 10 (50%) out of 20 cord blood samples showed a significant dose- dependent decrease in CFU-GM numbers. Erythroid progenitors were less affec ted by PCB126. At 10(-8) M and 10(-6) M PCB126. respectively only two (12%) and three (18%) out of 17 cord blood samples showed a significant decrease in BFU-E numbers. The presence or absence of the GST mu gene was determine d using PCR. The GST mu gene was present in 52% (14 out of 27 samples teste d) of the cord blood samples. Damage to the myeloid and erythroid haemopoie tic progenitor cells at either PCB126 concentrations was not correlated wit h the presence of the GST mu gene. (C) 1999 Elsevier Science Ltd. All right s reserved.