Amnion invasion assay

Fig. 4.3. (A) Diagram of the amnion invasion assay. The invasion chamber represents a cylindrical well produced by a Teflon ring (a) to which epithelium-free amnion (b) is fastened with the aid of a viton ring (c), to face the BM side up and stromal side down. A smaller lower chamber is created by a silicone rubber ring support attached to the bottom of a 35-mm tissue culture well (d) with silicone grease, and filled with medium. The (upper) invasion chamber is placed on this support, and medium with or without additives (to be tested for invasion-blocking or stimulating ability) is added to this chamber 1 h prior to the addition of labeled cells to be tested for invasive ability. Medium is then added to the tissue culture well (d) outside these chambers to bring the fiuids inside and outside the Teflon ring to the same level (e) represents a well that includes the complete invasion chamber seeded with cells on the BM. (Reproduced from Yagel et al., 1989.) (B) (a) Human amnion. Epithelium (EP), basement membrane (BM), connective tissue stroma (ST). Haematoxylin-eosin PAS stain, (b) Denuded human amnion membrane. Basement membrane (BM), connective tissue stroma (ST), Milfipore filter (F). Haematoxylin-eosin, PAS stain. (Reproduced from Russo, 1986.)...

Hendrix, M. J. C., Seftor, E. A., Seftor, R. E. B., Misiorowski, R. L., Saba, P. Z., Sundareshan, P. and Welch, D. R. (1989). Comparison of tumor cell invasion assays human amnion versus reconstituted basement membrane barriers. Invasion and Metastasis 9, 278-297. 

Following cell seeding and incubation, nonmigrated cells on the upper surface of the filter are removed, and the cells that actively migrated to the under surface of the filter are counted. This assay—as well the amnion assay—may also be used to investigate the ability of hydrolase inhibitors or growth factors to restrain or augment the invasive activity respectively, as well as measure the capacity of a chemoattractant to accelerate the movement of invasive cells. 

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