Ex vivo expansion CD34(+)/AC133(+) - selected autologous peripheral blood progenitor cells (PBPC) in high-risk breast cancer patients receiving intensive chemotherapy

AC133 antibody provides an alternative to CD34 for the selection and charac terization of cells necessary for engraftment in transplant situations. We studied the effect of stem cell factor (SCF), interleukin 3 (IL-3) and inte rleukin 11 (IL-11) on the ex vivo expansion of human CD34(+)/AC133(+) proge nitors isolated from leukapheresis products from chemotherapy plus granuloc yte-colony-stimulating factor (G-CSF) -mobilized adult donors. MiniMACS AC1 33(+) isolated cells contained a mean of 85% (80-90) AC133(+) cells. Enrich ed AC133(+) cells co-expressed CD34(+) 80%, CD71(low) 36.6% and CD33(+) 6.6 %. After a seven-day ex vivo expansion in the presence of SCF + IL-3 + IL-1 1, the number of cells increased 19 times. These cells expressed a mean 12% CD34(+) and 74% CD71(+) (23% CD71(high)) and 59% CD33(+). This means that the absolute number of CD34(+) cells increased slightly, the number of CD33 (+) increased 100 times and cells with high density CD71(high) (23%) appear ed. These cells represent the cells committed to erythroid differentiation. The increase in the number of CFU-GM with various combinations of cytokine s SCF + Il-3 + IL-11 will be discussed. The number of CFU-GM in culture aft er a seven-day ex vivo expansion in the presence of SCF + IL-3 + IL-11 incr eased 45 times.