Embodiments described herein generally provide for expanding cells in a cell expansion system. The cells may be grown in a bioreactor, and the cells may be activated by an activator (e.g., a soluble activator complex). Nutrient and gas exchange capabilities of a closed, automated cell expansion system may allow cells to be seeded at reduced cell seeding densities, for example. Parameters of the cell growth environment may be manipulated to load the cells into a particular position in the bioreactor for the efficient exchange of nutrients and gases. System parameters may be adjusted to shear any cell colonies that may form during the expansion phase. Metabolic concentrations may be controlled to improve cell growth and viability. Cell residence in the bioreactor may be controlled. In embodiments, the cells may include T cells. In further embodiments, the cells may include T cell subpopulations, including regulatory T cells (Tregs), for example.

Embodiments described herein generally provide for expanding cells in a cell expansion system. The cells may be grown in a bioreactor, and the cells may be activated by an activator (e.g., a soluble activator complex). Nutrient and gas exchange capabilities of a closed, automated cell expansion system may allow cells to be seeded at reduced cell seeding densities, for example. Parameters of the cell growth environment may be manipulated to load the cells into a particular position in the bioreactor for the efficient exchange of nutrients and gases. System parameters may be adjusted to shear any cell colonies that may form during the expansion phase. Metabolic concentrations may be controlled to improve cell growth and viability. Cell residence in the bioreactor may be controlled. In embodiments, the cells may include T cells. In further embodiments, the cells may include T cell subpopulations, including regulatory T cells (Tregs), helper, naïve, memory, or effector, for example.

The present disclosure provides, in part, a receptacle for filtering a liquid. The receptacle comprises a plurality of hollow fibers extending the length of the receptacle and at least one solid absorbent material occupying a space between the plurality of hollow fibers. Each hollow fiber comprises at least one opening and a lumen defined by the walls thereof, allowing the liquid to flow through. The hollow fiber walls have a porosity profile selective to passage of waste materials contained in the liquid from the lumen to the solid absorbent material(s), thereby filtering the liquid. Also provided is a system as well as a method for filtering and recycling a cell culture medium.

Embodiments described herein generally provide for the expansion of cells in a cell expansion system using an active promotion of a coating agent(s) to a cell growth surface in some embodiments. A coating agent may be applied to a surface, such as the cell growth surface of a hollow fiber in a bioreactor, by controlling the movement of a fluid in which a coating agent is suspended, by changing flow rates, by changing flow directions, by rotation of the bioreactor, and/or combinations thereof.

What is described herein relates to a method for improving a cell culture comprising a) heating a cell culture process fluid using a single-use dense membrane hollow fiber module wherein said single-use dense membrane hollow fiber module comprises a plurality of dense membranes arranged as hollow fibers in a housing and/or b) wherein the cell culture has at least one cell culture chamber and at least the bottom or at least the top of said cell culture chamber is covered with an insulation.

A method, and also a gas supply system without a separate humidifying apparatus, for supplying gas to a plurality of bioreactors, divides a constant gas stream with high distribution accuracy into a plurality of gas substreams having a mandated volume flow, which can be kept constant at the mandated level even when during gas supply there is fluctuation in the opposing pressure in the gas line to the respective bioreactor, and decouples a gas distribution from the opposing pressure by hydrostatic pressure compensation, with the gas distribution at the same time producing an obligatory humidification of the gas stream.

This disclosure relates to the use of a hydrophobic hollow fiber filter for the filtration of cell cultures and other biological perfusions, due to its resistance to fouling, as well as the ability to filter solutions with a high solid content. A hydrophobic hollow fiber filter may be used within a filter housing in conjunction with a process vessel and a traditional separation system. When the system is used with alternating tangential flow or tangential flow filtration, the hydrophobic hollow fiber filter results in more effective filtration of the filtrate, leading to greater concentration of the retentate, even in solution containing high levels of solids.

Embodiments described herein generally provide for the expansion of cells in a cell expansion system using an active promotion of a coating agent(s) to a cell growth surface in some embodiments. A coating agent may be applied to a surface, such as the cell growth surface of a hollow fiber in a bioreactor, by controlling the movement of a fluid in which a coating agent is suspended, by changing flow rates, by changing flow directions, by rotation of the bioreactor, and/or combinations thereof.

Embodiments for loading and expanding particular cell types are described. Embodiments may include the use of hollow fiber membranes with particular characteristic such as hollow fibers with inner diameters that provide mechanical stimulus (e.g., radius of curvature greater than a dimension of a cell). In addition, embodiments may provide for manipulation of flow rates and other features that also provide mechanical stimuli and promote or enhance the growth of particular types of cells.

Described are embodiments for expanding cells in a bioreactor. In one embodiment, methods are provided that distribute cells throughout the bioreactor and attach cells to specific portions of a bioreactor to improve the expansion of the cells in the bioreactor. Embodiments may be implemented on a cell expansion system configured to load, distribute, attach and expand cells.