Table 1.

Checkerboard analysis of the chemotactic activity of 4N1K

4N1K in lower chamber (μM)	4N1K in upper chamber (μM)
	0	25	50	10
0	22 ± 3	18 ± 2	16 ± 3	11 ± 3
25	30 ± 4	24 ± 2	20 ± 3	18 ± 4
50	40 ± 5	32 ± 3	26 ± 4	16 ± 3
100	54 ± 7	39 ± 5	32 ± 4	23 ± 4

Different gradient conditions were created by adding various concentrations of 4N1K to the upper and lower compartment of the chamber as indicated. The motility response is expressed as mean ± SE cells per high-power field (five fields for each of triplicate wells were counted).