A system for processing cells is disclosed. The system may include a container having an inner wall, a plunger adapted to be slidably positioned within the container, at least one inlet port through which a fluid can enter the container, at least one outlet port through which a fluid can exit the container, at least one effluent port through which an effluent can exit the container, a first check valve in fluid connection with the inlet port and a second check valve in fluid connection with the effluent port. The plunger may include a filter that allows fluid to pass therethrough but prevents cells from passing therethrough. Rearward motion of the plunger may be adapted to draw fluid into the system via the inlet port and forward motion of the plunger may be adapted to force effluent out of the system via the effluent port.