[Significance and modulation of production of tumor growth inhibitor derived from human embryonic myofibroblasts].

In this report, the production and modulation of tumor growth inhibitor (HFDI) derived from human embryonic myofibroblasts were studied. HFDI was obtained from 3/30 cultures of human embryonic myofibroblasts, which was obviously lower than the incidences of Australia Caucasian's myofibroblast (6/6) and adult's skin fibroblast (4/6). It is suggested that the inheritance play certain role in HFDI production. Calf serum had a significant effect on HFDI production, though without any linear relationship. It seems that HFDI is not derived from calf serum but the factors influencing the production of HFDI are in the calf serum. HFDI could be induced by inactivated BCG from non- or low-producing myofibroblasts. It is indicated that the production of HFDI is related to bacterial contamination (in vitro) or infection (in vivo). The hypothesis is proposed that tumor inhibitors be induced by bacterial infection from the fibroblasts. HFDI-like activity was identified in 4 healthy donors' sera suggesting that HFDI could enter the blood.