Primary culture

Primary culture refers to the stage of the culture after the cells are isolated from the tissue and proliferated under the appropriate conditions until they occupy all of the available substrate (i.e., reach confluence). At this stage, the cells have to be subculture (i.e., passaged) by transferring them to a new vessel with fresh growth medium to provide more room for continued growth.

Cell Line

After the first subculture, the primary culture becomes known as a cell line. Cell lines derived from primary cultures have a limited life span (i.e., they are finite; see below), and as they are passaged, cells with the highest growth capacity predominate, resulting in a degree of genotypic and phenotypic uniformity in the population.

Cell strain

If a subpopulation of a cell line is positively selected from the culture by cloning or some other method, this cell line becomes a cell strain. A cell strain often acquires additional genetic changes subsequent to the initiation of the parent line.

One can use cell culture inserts to:

Create a cell culture environment that closely resembles an in vivo state

Allow polarized cells to carry out metabolic activities in a more natural manner because the cells feed both apically and basolaterally

Co-culture cells with or without cell-to-cell contact

Design a diversity of experiments using various pore sizes, membrane types, and coatings

PET (Polyester or Polyethylene Terephthalate)

Membrane optic:

Clear PET inserts permit sufficient optical transparency for visualization of cell outlines by phase contrast microscopy.

Translucent PET membranes have a high pore density, which allows maximum diffusion of materials between the insert and receiver plate.

Surface treatments: