Zigmond chamber

Fig. 2. Theoretical data for Zigmond chamber. Equation 2 was used to calculate the concentration dynamics. Panels (a, d) present the concentration C. The spatial gradient dOtl/is presented in panels (b, e) and the temporal gradient dC/df in panels (c,f),all at different positions and times from the source containing 1 xM of cAMRThe graybars m the left panels and the thick line in the right panels indicate the place of chemotactic observation (650-750 xm from the source).

The cAMP waves are propagated in the field of cells with a speed V = dx/dtof 300 pm/min (13). Therefore, the temporal gradient is given by dC/df = v VC Thus, the temporal gradient follows the spatial gradient and reaches a maximum value of about 17.5 nM/s at 1-min after arrival of the cAMP wave. In the Zigmond chamber the temporal gradient reaches a maximum of 3 nM/s at 2 min after application of cAMP (Fig. Ic). 

We thank Douwe Veltman and Ineke Keizer-Gunnink for obtaining experimental data on the Zigmond chamber (Fig. 1) and micropipettes (Figs. 3 and 4), respectively. 

The other assay therefore employs a one-dimensional chemoattractant gradient, established in a Zigmond chamber, which was originally designed for the evaluation of leukocyte chemotaxis [194]. In this chamber, which is built from two parallel, rectangular wells separated by a wall (Figure 10), a one-dimensional concentration gradient is... 

Figure 10. Chemotaxis-detection system in a Zigmond chamber. Top a transverse section. Bottom a plan view. A concentration gradient is formed between the covei slip and the partition wall [p] separating two wells (Cl and C2). See text for details. (Taken with permission from Giojalas et al. (57].]...

Although the system contemplates the distinction of chemotaxis and chemokinesis, it does not account for the complexities of the extravasation process. To emulate these, the filter can be coated in advance. Even though some studies use components of the extracellular matrix such as collagen, we have found that the culture of endothelial cells on top of the filter optimally mimics in vivo conditions. Similarly, other chemotaxis assays are available in the market, most of them based on a two-chamber model. For instance, the Zigmond chamber and its improvement, the Dunn chamber allow for the visuahzation of the cell migration toward the chemoattractant, but they do not allow for a more in vivo simulation (Sackmann, Fulton, Beebe, 2014). 

Direct-viewing chemot-axis chamber (Dunn, Zigmond, Insall)... 

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