Preparation and cultivation of primary human amnion cells.

Human amnion tissue is readily available to most laboratories as a source of cells for tissue culture studies. It has proved to be a useful tool in the field of virus research, and it offers impor tant potentials in the field of cancer research as a source of normal human cells easily obtained in primary cultivation. Many investigators have been concerned with the problem of malignant properties of cells in serial cultivation. Recent in vestigations from this laboratory (3, 7) have de scribed the development of strains of amnion cells in serial cultivation. The comparison of the bio logical properties of such strains of amnion cells with their prototype cell in primary cultivation may lead to some understanding of the origin and development of cells in serial cultivation and of the development of possible malignant properties during continued cultivation. A preliminary report (8) from this laboratory first described the cultivation and poliovirus in fection of human amnion cells from the mem branes from ten normal deliveries. We have con tinued to explore ways to simplify and improve the preparation of human amnion cells, to increase the volume of cultures for virus assays (2) and viruscell studies (1), and to utilize the cells as a source of normal human tissue for the comparison of the biological characteristics of primary and estab lished strains of human cells in tissue culture (7). We describe in this publication an improved and modified procedure for the primary cultivation of human amnion cells based on experience during the last year with over 400 membranes. This pro cedure allows a high degree of flexibility in the collection of the membranes, their storage and trypsinization, and in the culture and maintenance of the cells before experimentation. Other labora-