Overview of CD34+ cell selections and NK cell culturing procedures.

Table 2 shows a summary of all different experiments and the corresponding UCB donors using the different culture methods I–III and media (see Figure 1). The purity and the total number of CD34+ cells after immunomagnetic selection determined by FCM are depicted for each UCB donor. The CD56 content after 5 weeks (Method I and II) or 6 weeks (Method III) of culture was analyzed by FCM as described in Materials and Methods. Numbers of NK cells represent a theoretical calculation based on the actual expansion rates of CD56+ NK cells and were calculated using the initial numbers of CD34+ cells from each UCB multiplied by the NK cell expansion rate from each culture procedure. The mean ± standard deviation (SD), range and median are calculated for each method and medium separately.