Influence of C3a on chemotaxis of clonogenic CD34⁺ cells.

The CD34⁺ cells showing chemotaxis in response to medium alone (control), C3a (1 μg/mL), low-dose SDF-1β (10 ng/mL), C3a (1 μg/mL) plus low-dose SDF-1β (10 ng/mL), and high-dose SDF-1β (300 ng/mL) were collected after chemotaxis assay from the lower chambers of transwells and plated in methylcellulose. The number of colonies formed by cells harvested from the lower chambers of transwell plates is shown as fold increase compared with control values. Data are pooled from quadruplicate samples from 3 independent experiments. * P < .00001.