the bulk flow at the downstream edge of the functional flow chamber without further description it is believed that one of ordinary skill in the art can using the preceding description and the following illustrative examples make and utilize the compounds of the present invention and practice the claimed methods the following example is given to illustrate the present invention it should be understood that the invention is not to be limited to the specific conditions or details described in this example in order to establish protocol without sacrificing precious hspcs we utilized a model system where cd34 kg1a cells represented the hspcs and cd34 u2212 hl60 cells represented the cd34 u2212 abm cells the kg1a hl60 model was used to determine an optimum p selectin concentration for subsequent hspc experiments we initially found that kg1a and hl60 cells rolled at very similar velocities at all p selectin concentrations tested so based on the data from eniola et al 2003 we co immobilized anti cd34 antibody together with the p selectin and found that at 0 5 u03bcg ml p selectin and 40 u03bcg ml anti cd34 there was a significant difference between the rolling velocities of the two cells fig6 a this more closely represented previous findings that hspcs tend to roll slower than cd34 u2212 cells on selectins which was.