Patent Publication Number: US-2005143244-A1

Title: Apparatus and method for expressing fluid materials

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This application is a divisional of U.S. patent application Ser. No. 09/082,200 filed on May 20, 1998, which claims the benefit under Title 35, U.S.C. § 119(e) of pending U.S. Provisional Application Ser. No. 60/047,213, filed May 20, 1997, entitled “Cell Processing System”, incorporated herein by reference. This application is also related to co-pending U.S. patent applications entitled: “Rotating Seals for Cell Processing Systems” (U.S. application Ser. No. 09/081,733 filed May 20, 1998, now abandoned); “Fluid Management Systems” (U.S. application Ser. No. 09/082,200 filed May 20, 1998); “Optical Sensors for Cell Processing System” (U.S. Pat. No. 6,175,420); and “Cell Processing Systems” (U.S. application Ser. No. 09/082,341 filed May 20, 1998, now abandoned), the entire disclosures of which are hereby incorporated by reference. 
    
    
     BACKGROUND  
      In order to prepare cells for transfusion or transplantation, it may be necessary to process the cells using an operation, which removes unwanted chemical and/or cellular elements. For example, in preparing frozen erythrocytes for transfusion, erythrocytes are separated from cryopreservatives and other blood components, such as white blood cells, platelets, and subcellular debris. It is important that cell processing be performed under conditions which minimize the risk of microbial contamination.  
      Further where cell (such as eukaryotic cells, bacteria, or yeast) are cultured in bioreactors for the synthesis of pharmaceuticals, it is necessary to separate the cells from their culture medium.  
      A number of devices and techniques have been developed to process cells for the foregoing purposes, as described, for example, in European Patent No. 00575858/EP B1 by Witthaus et al. And U.S. Pat. No. 4,919,817 by Schoendorfer and Williamson, and other patents as set forth below.  
      Generally, cell processing requires steps in which cells or cell elements are separate from a liquid phase. This separation is typically accomplished by centrifugation.  
      Also as part of the separation process, a number of devices have been developed which incorporate a means of expressing (i.e., promoting the exit) fluid which has been removed from harvested cells. Disclosures relating to expression include U.S. Pat. No. 4,332,351 by Kellogg and Druger, U.S. Pat. No. 4,010,894 by Kellogg and Kruger, U.S. Pat. No. 4,007,871 by Jones and Kellogg, U.S. Pat. No. 3,737,097 by Jones et al., EP 00265795/EP B1 by Polaschegg, U.S. Pat. No. 4,934,995 by Cullis, U.S. Pat. No. 4,223,672 by Terman et al., and U.S. Pat. No. 4,213,561 by Bayham.  
      The present invention relates to biological fluid and/or cell processing apparatus and, more particularly, to an apparatus for separating fluid materials having different densities from each other, most typically in a centrifugal field, or otherwise such as in a gravitational field. More particularly, the present invention relates to an apparatus designed to add additional fluids to wash or otherwise treat one or more of the cellular components after the less dense fractions of the solution have been separated and expressed from, or pushed out of, the centrifugal (or gravitational) field. Automated systems for processing cellular material in this manner have typically relied on inefficient centrifugal containment devices and complex fluid management hardware to remove the separated fractions from the centrifuge chamber. Sterility, temperature control, ratio of volume of input fluids, ability to process variable volumes and simplification of the mechanisms used for expressing materials out of a cell or fluid processing chamber are concerns that have been addressed in a variety of inefficient or expensive apparatus and methods in the past.  
     SUMMARY OF THE INVENTION  
      In accordance with the invention there is provided an apparatus for selectively expressing one or more selected fluid materials out of a fluid container, wherein each of the selected fluid materials has a selected density and wherein the fluid container comprises a round enclosure having a flexible wall and an exit port sealably communicating with the fluid container for enabling the selected fluid materials contained therein to be expressed out of the fluid container through the exit port, the apparatus comprising, a centrifuge rotor having a round centrifuge chamber of selected volume, the centrifuge rotor being controllably rotatable around a central axis by a motor mechanism; a round expandable enclosure disposed within the centrifuge chamber having a rotation axis coincident with the central rotation axis and a flexible wall, the fluid container having a rotation axis and being coaxially receivable within the centrifuge chamber, the expandable enclosure being sealably connected to a source of an expresser fluid which has a density selected to be greater than the density of each of the selected one or more fluid materials disposed in the fluid container; a pump for controllably pumping a selected volume of the expresser fluid into and out of the expandable enclosure wherein the fluid container is receivable within the centrifuge chamber; a retaining mechanism for holding the fluid container within the centrifuge chamber in a coaxial position wherein the flexible wall of the fluid container is in contact with the flexible wall of the expandable enclosure.  
      The expandable enclosure preferably comprises a flexible membrane sealably attached to a surface of the rotor such that the centrifuge chamber is divided into a first chamber for receiving the fluid container and a second fluid sealed chamber for receiving the expresser fluid. The flexible wall of the expandable enclosure typically comprises an elastomeric sheet material. The apparatus further typically includes a heater mechanism having a control mechanism for selectively controlling the temperature of the expresser fluid.  
      Due to its higher density, the expresser fluid which is pumped into the expandable enclosure travels to a circumferential position within the expandable enclosure which is more radially outward from the central axis than a circumferential position to which the one or more selected fluid materials in the fluid container travel when the rotor is drivably rotated around the central axis.  
      The fluid container typically has a first radius and the second fluid sealed chamber typically has a second radius which is at least equal to the first radius of the fluid container, wherein the expresser fluid which is pumped into the second fluid sealed chamber travels to an outermost circumferential position within the second fluid sealed chamber which is more radially outward from the central axis than a circumferential position to which the one or more selected fluid materials in the fluid container travel when the rotor is drivably rotated around the central axis.  
      Further, in accordance with the invention, there is provided in a centrifuge apparatus comprising a rotor having a centrifuge chamber which is controllably rotatable around a central axis, a method for expressing one or more selected fluid materials each having a selected density out of a fluid container which contains the selected fluid materials wherein the fluid container comprises a round enclosure having a radius, a rotation axis, a flexible wall and an exit port sealably communicating with the fluid container for enabling the selected fluid materials contained therein to be expressed out of the fluid container through the exit port, the method comprising: forming a round expandable enclosure within the centrifuge chamber wherein the expandable enclosure has a flexible wall, a radius and a rotation axis coincident with the central axis of the rotor; mounting the fluid container coaxially within the centrifuge chamber such that the flexible wall of the fluid container faces the flexible wall of the expandable enclosure; selecting an expresser fluid having a density greater than the density of each of the selected fluid materials; pumping the selected expresser fluid into the expandable enclosure in an amount sufficient to expand the expandable enclosure such that the flexible wall of the expandable enclosure contacts the flexible wall of the fluid container; and, drivably rotating the rotor around the central axis before, during or after the step of pumping.  
      Further, in accordance with the invention, there is provided an apparatus for selectively expressing one or more selected fluid materials out of a fluid container, wherein each of the selected fluid materials has a selected density and wherein the fluid container comprises a round enclosure having a flexible wall and an exit port sealably communicating with the fluid container for enabling the selected fluid materials contained therein to be expressed out of the fluid container through the exit port, the apparatus comprising; a separation housing having a round chamber of selected volume, the housing having a central axis; a round expandable enclosure disposed within the round chamber having an axis coincident with the central axis of the separation chamber and a flexible wall, the fluid container having an axis and being coaxially receivable within the round chamber, the expandable enclosure being sealably connected to a source of an expresser fluid which has a density selected to be greater than the density of each of the selected one or more fluid materials disposed in the fluid container; a pump for controllably pumping a selected volume of the expresser fluid into and out of the expandable enclosure wherein the fluid container is receivable within the round chamber; a retaining mechanism for holding the fluid container within the round chamber in a coaxial position wherein the flexible wall of the fluid container is in contact with the flexible wall of the expandable enclosure.  
      Further, in accordance with the invention, there is provided an apparatus for selectively expressing one or more selected fluid materials out of a fluid container, wherein each of the selected fluid materials has a selected density and wherein the fluid container comprises a round enclosure having a flexible wall and an exit port sealably communicating with the fluid container for enabling the selected fluid materials contained therein to be expressed out of the fluid container through the exit port, the apparatus comprising: a centrifuge rotor having a round centrifuge chamber of selected volume, the centrifuge rotor being controllably rotatable around a central axis by a motor mechanism; a round expandable enclosure disposed within the centrifuge chamber having a rotation axis coincident with the central rotation axis and a flexible wall, the fluid container having a rotation axis and being coaxially receivable within the centrifuge chamber, the expandable enclosure being sealably connected to a source of an expresser fluid; a pump for controllably pumping a selected volume of the expresser fluid into and out of the expandable enclosure; wherein the fluid container has a flexible wall and is receivable within the centrifuge chamber such that the flexible wall of the fluid container faces the flexible wall of the expandable enclosure; a mechanism for filling the fluid container with any preselected variable volume of the one or more selected fluid materials which is less than the selected volume of the centrifuge chamber; a retaining mechanism for holding the fluid container completely within the centrifuge chamber upon expansion of the expandable enclosure.  
      Further, in accordance with the invention, there is provided in a centrifuge apparatus comprising a rotor having a centrifuge chamber of a selected volume which is controllably rotatable around a central axis, a method for expressing one or more selected fluid materials each having a selected density out of a fluid container which contains the selected fluid materials wherein the fluid container comprises a round enclosure having a rotation axis, a flexible wall and an exit port sealably communicating with the fluid container for enabling the selected fluid materials contained therein to be expressed out of the fluid container through the exit port, the method comprising: forming a round expandable enclosure within the centrifuge chamber wherein the expandable enclosure has a flexible wall and a rotation axis coincident with the central axis of the rotor; mounting the fluid container coaxially within the centrifuge chamber such that the flexible wall of the fluid container faces the flexible wall of the expandable enclosure; filling the fluid container with any preselected variable volume of the one or more of the selected fluid materials which is less than the selected volume of the centrifuge chamber before, during or after the step of mounting; pumping a selected expresser fluid into the expandable enclosure in an amount sufficient to expand the expandable enclosure such that the flexible wall of the expandable enclosure contacts the flexible wall of the fluid container; holding the fluid container completely within the centrifuge chamber during the step pumping and, drivably rotating the rotor around the central axis before or during the step of pumping.  
      The step of pumping typically includes preselecting the expresser fluid to have a density greater than the density of each of the selected fluid materials. The method may further comprise placing the expresser fluid at one or more selected temperatures prior to or during the step of pumping.  
      Further, in accordance with the invention, an apparatus for selectively expressing one or more fluid materials out of a fluid container includes an IR temperature sensor (e.g., an IR thermocouple) for measuring the temperature of the fluid materials located in the fluid container prior to the selective expressing. The apparatus also includes a second expressing temperature sensor for measuring the temperature of the ambient between the fluid container and the IR sensor. Alternatively, the second temperature sensor may be replaced by another means that characterize changes in the refractive index of the infrared radiation emitted from the fluid material in order to correct the IR data.  
      Further, in accordance with the invention, there is provided a centrifuge apparatus comprising of a rotor having a centrifuge chamber of a selected volume which is controllably rotatable around a central axis, a method for consistently processing a selected biological cell material between separate processing cycles in the centrifuge apparatus, the method comprising: selecting a fluid material having a predetermined composition for treatment of the selected biological cell material; forming a round expandable enclosure within the centrifuge chamber wherein the expandable enclosure has a flexible wall and a rotation axis coincident with the central axis of the rotor; mounting a round fluid container having rotation axis, a flexible wall and an exit port sealably communicating with the fluid container coaxially within the centrifuge chamber such that the flexible wall of the fluid container faces the flexible wall of the expandable enclosure; filling the fluid container with a volume of the selected biological cells and a volume of the selected fluid material in a predetermined ratio before, during or after the step of mounting; pumping a selected expresser fluid into the expandable enclosure in an amount sufficient to expand the expandable enclosure such that the flexible wall of the expandable enclosure contacts the flexible wall of the fluid container; holding the fluid container completely within the centrifuge chamber during the step pumping; drivably rotating the rotor around the central axis before or during the step of pumping; and, repeating the steps of mounting, filling, pumping, holding and drivably rotating at least once.  
      The heater control mechanism typically includes a program for automatically controlling the temperature of the expresser fluid. The expresser fluid is typically circulated through a reservoir, within which, the fluid is in thermal contact with certain devices that transfer thermal energy to or from the fluid in response to a control algorithm. These thermal devices may include Peltier Devices, electric resistance submersion heaters, air-cooled radiators, or other similar devices or some combination of these types of thermal transfer devices. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The invention is described with reference to representative examples and embodiments shown in the accompanying drawing wherein:  
       FIG. 1  is a perspective view of an interactive cell processing system;  
       FIG. 2  is a conceptual flow diagram displaying operation of an interactive cell processing system;  
       FIG. 3  is a block diagram of the interactive cell processing system of  FIG. 1 ;  
       FIG. 4  is a left side perspective view of the  FIG. 1  system;  
       FIG. 5  is an isometric exploded view of components of a subassembly used for expressing selected fluid materials disposed in a flexible container;  
       FIG. 6  is an isometric exploded view of certain of the components shown in  FIG. 5 ;  
       FIG. 7  is a side cross-sectional view of certain components of the expresser system subassembly shown in  FIG. 5  taken along one plane which does not intersect one of the fluid flow grooves  410  in check  408 ;  
       FIG. 8  is another side cross-sectional view of certain components of the expresser system subassembly shown in  FIG. 5  taken along a plane which does intersect one of the fluid flow grooves  410  in check  408 ;  
       FIG. 9  is a schematic side cross-sectional view of the  FIG. 8  view showing the flexible membrane component  411  seated initially at the beginning of a processing cycle along the curved surface of the bowl or donut shaped separation chamber  421  of chuck  408 ;  
       FIG. 10  is a close-up cross-sectional view of a portion of  FIG. 9  showing the expresser fluid chamber  420  partially filled with expresser fluid at a later stage in a typical processing cycle;  
       FIG. 11  is a view of  FIG. 10  at an even later stage of a typical processing cycle showing the expresser fluid chamber  42  filled to a greater degree/volume than the chamber is filled in  FIG. 10 ;  
       FIG. 12  is another schematic side cross-sectional view of the expresser system subassembly of  FIGS. 4-11  showing additional components by which expresser fluid is input from a pumping source through a central drive shaft which is rotatably driven;  
       FIG. 13  is an isometric view of the  FIG. 5  components in assembled form;  
       FIG. 14  is an exploded isometric view of a rotating seal used in conjunction with an expresser system of the invention;  
       FIG. 15  is an isometric view of the  FIG. 14  components in assembled form; and  
       FIG. 16  is an exploded side cross-sectional view of the  FIG. 14  rotating seal components. 
    
    
     DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS  
      Referring to  FIGS. 1 and 3 , an interactive cell processing system  10  includes a cell module  12 , a supply module  20 , a fluid distribution module  40 , a processing module  60 , a collection module  70  (not shown in  FIG. 1 ) and a control module  80 . These modules are operatively interconnected for processing biological cells in a sterile environment. Cell module  12  is constructed for short term or long-term storage of biological cells for processing. Supply module  20  includes several containers for storing different process chemicals including saline or other fluids used for processing the cells and/or sterile air, typical processing being the treating of the cells with selected active materials such as enzymes, buffers, and polyethylene glycol (PEG), nucleic acids and the like, washing the cells with selected fluids such as buffers, saline and the like and compacting the cells for purposes of separating them from the suspending media. The containers are connected to fluid distribution module  40  by a set of conduits. Fluid distribution module  40  includes several valves and sensors for dispensing controlled amounts of the process chemicals from supply module  20  to processing module  60  and for dispensing a known amount of the biological cells from cell module  12  to processing module  60 . Furthermore, fluid distribution module  40  is constructed to direct the process waste from processing module  60  to a waste container  72  and processed cells to a cell storage container  74 , both of which are located in collection module  70 , while maintaining the purity and sterility of the cells. Control module  80  directs the entire process according to a selected algorithm.  
      In general, the operation of cell processing system  10  is shown in  FIG. 2 . Control module  80  executes a processing algorithm selected initially  98 . Control module  80  includes a logic controller that receives real-time data from several in-line sensors arranged in a processing loop. A mass sensor (or a volume sensor) measures an initial amount of the provided biological cells  94  and sends the data to control module  80 . Control module  80  controls the amount of cells dispensed to processing module  60  in accordance with the processing algorithm. Based on the provided amount of the biological cells, control module  80  also calculates the individual doses of the process chemicals  100  and directs a set of control valves to dispense the chemicals  102  in a selected order to processing module  60 , again in accordance with the processing algorithm.  
      Control module  80  executes iteratively the processing algorithm. Control module  80  receives data from the individual sensors (e.g., a weight sensor, a volume sensor, a temperature sensor, an optical sensor, a resistance or capacitance sensor, a flow sensor, a pressure sensor or another sensor arranged to monitor the transferred matter in a liquid, gaseous or solid state). After dispensing the selected amount of one or several processing chemicals to processing module  60 , control module  80  regulates the temperature and the time of processing and directs the processing module to agitate, mix or otherwise treat the cells with the process chemicals. Depending on the processing algorithm, control module  80  may manage several processing cycles. At the end of each cycle, processing module  60  may separate the processed cells from intermediate products and from the process waste. During the separation process, fluid distribution module  40  detects the fluid component being expressed from processing module  60  and directs the separated components to different containers for disposal  110  or storage  112 . Each processing cycle may use a different processing chemical and different processing conditions. Cell processing system  10  can also process different types of cells at the same time or sequentially. Furthermore, cell processing system  10  may also partially process biological cells and then store them in cell storage container  74  (shown in  FIG. 3 ), which may include a temperature control system. The processed cells may be later automatically dispensed from cell storage container  74  and processed using another processing algorithm. The processed cells may also be grown in culture prior to another use.  
      Cell processing system  10  may process any collection of cells (such as blood cells) which are fluid enough in mass composition to flow readily through biological fluid delivery tubing, bags and the like.  
      Referring again to  FIG. 3 , in one preferred embodiment of the cell processing system, cell module  12  includes a weight sensor  14  arranged to weigh red blood cells provided in a bag  16 . Tubing  17  connects a bag  16  to a leuko filter  18  and to fluid distribution module  40 . Supply module  20  includes a bag  21  with enzyme A 1 /B, a bag  22  with enzyme A 2 , a bag  23  with 140 m Molar Potassium Phosphate DiBasic pH 9.0 (DPP), a bag  24  with PEG (polyethylene glycol), a bag  25  with storage solution, and a bag  26  with Phosphate Citrate Isotonic (PCI). Each bag is connected by tubing  28  to fluid distribution module  40 . A weight sensor  29  is constructed to weigh any of the above-mentioned fluids located in supply module  20 . Supply module  20  also includes a compressor  30  connected via a filter  31  and a check valve  32  to air reservoir  33 , which stores sterile air used for cell processing. Pressure switch and sensor  34  is in communication with air tubing  36 , which delivers sterile air to an air filter located in fluid distribution module  40 . A regulator  37  connected to a solenoid valve  36  regulates the air pressure provided to fluid distribution module  40  and to processing module  60 . Fluid distribution module  40  includes a peristaltic pump  42  and twelve plunger valves  43  through  54  connected to a set of conduits for distributing the processed chemicals and the cells during the automated process. A pressure sensor  55  measures the fluid pressure during the process, and an optical detector  58  monitors the fluid to and from processing module  60 .  
      Processing module  60  preferably includes a centrifuge or sedimentation or gravity/separation chamber apparatus  62  and an expressor fluid system  64 . An IR temperature sensor  66  monitors the temperature of the processed chemicals or the cells located inside the centrifuge  62 . Collection module  70  includes a waste bag  72 , a saline solution bag  74 , and a product bag  76 . Collection module  70  also includes a weight sensor  76  connected to product bag  74  and arranged to weigh the processed red blood cells.  
      Specifically, the logic controller received input from: 
          the weight of the initial and final blood bags,     the weight of the processing fluids,     the temperature of the blood and the expressing fluid,     and the pressure of the fluid upstream from the sterilizing filter and the rotating seal as well as the pressure of the expressing fluid and the sterile air supply.        

      Based on a programmed algorithm, the controller sends output signals to: 
          the processing and expressor pumps,     the temperature controller (heating and cooling), typically a controller for heating and/or cooling the expresser fluid;     and any combination of the twelve valves.        

       FIG. 4  shows the  FIG. 1  apparatus  10  in a left side perspective view showing the expresser system components more clearly in assembled and mounted relationship relative to the overall apparatus  10 .  
      In particular, a motor  400  for rotatably driving a chuck or rotor (described in detail below), separation posts  401 , bearing housing  402 , mounting plate  403 , bucket  404 , a sliding cover  405  and an infrared sensor housing assembly  406  are shown in  FIG. 4 .  
      As shown in  FIGS. 5-13 , the bucket  404  receives a chuck or rotor  408  which is rotatably drivable around central axis  430  via interconnection to motor  400  through shaft  450  which is housed within bearing housings  451 - 453  and coupling  452 . As shown in  FIG. 12 , the motor  400  rotatably drives a shaft  455  which is connected to shaft  450  which is connected to chuck  408  which is mounted via grooves  456  and posts  457 ,  FIGS. 7, 8  within the bucket ( 404 ) for rotation therein.  
      As best shown in  FIG. 12 , expressor fluid is pumped from an external source  425 , i.e., external to the rotor, shaft and motor components, into a sealed annular space  458  which communicates with an axial fluid passage  416  thorugh drive shafts  455  and  450 . The axial fluid passage  416  communicates with a passage  475  in chuck  408  which communicates with grooves (channels)  410  on the inside surface of chuck  408 ,  FIGS. 5, 6 . As best shown in  FIG. 6 , the fluid delivery grooves  410  extend radially outwardly along a central flat circular surface  460  and further radially outwardly along the curved inside surface of chuck  408 .  
      The grooves (channels)  410  may be formed on a wall of the chuck  408 , and may extend from the central axis and end adjacent a circumference of the chuck (for example).  
      A pair of bearing seals  462 ,  FIG. 12 , enable the delivery of fluid from (and to) a stationary source  425  into space  458  and through the axis passage  416  of rotating shafts  455  and  450 . Bearings  464 ,  FIG. 12 , rotatably mount shaft  450  within housing  451 .  
      The chuck  408  has a round, donut or dish shaped chamber  421 ,  FIGS. 7, 8 ,  9 ,  12  within which the separation process occurs. The overall chamber  421  is divided into two separate enclosures, one being the space below flexible membrane  411 , and the other being the space within chamber  421  above membrane  411 . The space below membrane  411  is sealably enclosed via the sealed mating of the underside of the outside circumference of the membrane with the circumferential rim  409 ,  FIGS. 5, 6  of chuck  408  which is accomplished via the bolting of ring  412   FIGS. 7, 8  to rim  409  with membrane  411  sandwiched therebetween. Membrane  411  is also sealably mated to the central flat surface  460  of chuck  408  via the bolting of chuck plate  413 ,  FIGS. 6, 7  to the center of chuck  408  with the center of membrane  411  sandwiched therebetween,  FIGS. 6, 7 .  
      The flexible membrane  411  comprises a resilient stretchable or flexible material typically an elastomeric material such as silicone, urethane or other suitable engineering elastomer such as Eastman Ecdel or DuPont Hytrel. The membrane  411  is non-permeable to fluid or gas and inert and/or non-reactive and/or non-porous to conventional aqueous and organic fluids and biological cells such as blood cells. The membrane  411  material is selected to be a material which stretches and contracts, is resilient, robust, and does not crease or deform upon stretching or contracting.  
      In the chamber space  426  above the top surface of membrane  411  within chamber  421  is mounted round fluid enclosure  604 ,  FIGS. 5, 7 ,  8  within which one or more fluid materials to be processed in some fashion is/are disposed. The fluid enclosure  604  comprises a flexible material, typically a sheet of plastic which is non-porous and inert to aqueous and biological fluids generally. The plastic material of the fluid enclosure  604  typically comprises polyvinyl chloride (PVC), polyethylene, inert multilayered coextruded plastics such as Cryovac M312, Eastman Ecdel elastomer or other equivalent flexible, inert plastic sheet material. The fluid enclosure  604  typically comprises an enclosure such as a bag (which may be disposable) or another donut shaped enclosure having at least one wall or side comprised of a sheet of the flexible plastic material, the outside surface of which faces the upper/outside surface of membrane  411 .  
      The fluid enclosure  604  is typically filled with two or more fluids, such as an aqueous solution and a collection of biological cells which are to be separated from each other via centrifugal forces or via gravity/sedimentation. For purposes of the present invention, a collection of cells which is capable of flowing relatively smoothly through conventional fluid flow tubing (e.g. having a diameter of at least about 0.10 inches) is considered to be a fluid or fluid material.  
      Where two or more fluid materials are input into or disposed in the fluid enclosure  604 , each fluid material has a different density. The density of any and all materials which are input into or disposed within the fluid enclosure  604  is most preferably selected to be less than the density of the expressor fluid which is selected for input into the expressor space or chamber  420 ,  FIGS. 7-11 .  
      The density of the expressor fluid is preferably selected to be greater than the density of each of the materials disposed in the enclosure  604  so that upon rotation of chuck or rotor  408 , the expressor fluid will preferentially travel to the outermost circumference of the chamber  421  under the centrifugal force, as best shown in  FIGS. 10, 11  wherein in  FIG. 10 , a first selected volume of expressor fluid has been pumped into space/enclosure  420  and wherein in  FIG. 11 , a second greater volume of expressor fluid has been pumped into space/enclosure  420 .  FIGS. 10, 11  demonstrate that as the volume of the expresser fluid is increased within enclosure  420 , during the course of rotation of chuck or rotor  408 , the flexible membrane  411  stretches/expands from the outermost circumferential edge of flexible enclosure  604  radially inwardly, thus compressing enclosure  604  radially inwardly and forcing the fluids to flow out of the enclosure  604 , through exit port  632 , sequentially according to the density of the fluid materials, least dense first to most dense last.  
      In a typical processing cycle, at the beginning, the membrane  411  is disposed in a position where the membrane  411  is held under suction pressure closely adjacent to the curved inner surface of the processing chamber  421  as shown in  FIG. 9 . A processing bag/enclosure  604  which, having a fill volume equivalent to space  426 ,  FIG. 9 , is filled with a fluid containing biological cells disposed in an aqueous solution containing processing materials such as enzymes or buffers. The filled enclosure  604  is deposited in space  426 ,  FIG. 9 , and the enclosure  604  is retained or fixedly held within space  426  via cover plates or doors  415 ,  FIGS. 5-9 , which are hingedly attached to chuck or rotor  408 . At least the underside  472  of enclosure  604 ,  FIG. 5 , comprises a flexible sheet material. The enclosure  604  is positioned within space  426  such that the flexible underside  472  of enclosure  604  faces and/or makes external surface to surface contact with membrane  411  as shown in  FIG. 9 . Expressor fluid is then controllably pumped from source  425 ,  FIGS. 8,12 , into axial channel  416  and flows upwardly to channel space  475  and then,  FIG. 8 , through grooves  410  into sealed space  420 . During the course of pumping the expressor fluid into space  420 , the chuck/rotor  408  is typically drivably rotated, the expressor fluid travels to the outermost circumferential volume of the sealed space  420  under centrifugal force,  FIG. 10  and the membrane  411  is stretched/expands radially inwardly,  FIG. 10 , and continues to expand,  FIG. 11  radially inwardly. As can be readily imagined as the volume of expresser fluid increases within space  420 ,  FIGS. 10, 11 , the bag or enclosure  604  is compressed and the fluids contained within the bag/enclosure  604  are forced radially inwardly to flow out of an exit channel  632  or  636  which are sealably connected to and communicate with the interior space of enclosure  604 .  
      In another embodiment of the invention, relying on gravity force only, the rotor/chuck  408  may not necessarily be rotated during input/pumping in of the expressor fluid. In such an embodiment, the expressor fluid may fill the sealed expressor space  420  from the gravitational bottom of the chamber  421  and expand the space  420  from the bottom upwardly compressing the bag/enclosure  604  from the bottom upwardly. Because the two or more materials disposed within the bag/enclosure  604  have different densities, the two or more materials will separate from each other within the bag/enclosure  604  over a certain period of time (depending on the densities of the fluid materials) under the force of gravity. Once the materials have been allowed to separate over time, the expressor fluid may be pumped into space  420  and the gravitationally separated materials may be compressed out of an exit channel  632 ,  636  sequentially according to their densities, least dense first to most dense last.  
      The expressor fluid is preferably selected to have a lubricating effect on the rotating bearing seals  462 ,  FIG. 12 , and selected to be non-corrosive and not overly viscous. Most preferably the expressor fluid is a mixture of glycerine and ethylene glycol in a ratio of between about 40:60 and about 60:40, most preferably abut 50:50 (having a density of about 1.15) which, for the vast majority of biological fluid applications, has a density greater than the density of the biological fluids. Other examples of expressor fluids having a density greater than most biological fluids are glycerol and ethylene glycol diacetate which are less preferred. Any stable, non-corrosive, relatively non-viscous fluid preferably having a density greater than the density of each of the fluid materials disposed in the enclosure  604  may be used as an expressor fluid.  
      The enclosure  604  which receives the fluids to be processed is a sealed enclosure, preferably having a fluid input port  632 ,  636  which is/are readily sealably attachable to a readily selectable source of fluid, such as wash or preservative or compacting fluid or buffer or biological cell containing or enzyme containing fluid. Such selectable sources of input fluids may be each connected to a manifold or fluid management apparatus (e.g. a subassembly or subsystem of module  40 ,  FIG. 1 ) which can be programmed or otherwise readily controlled to deliver a selected fluid for input to the enclosure  604 . An output port of such a manifold or fluid management apparatus is readily sealably connectable to an input port  632 ,  636  of the enclosure  604 .  
      In the embodiment shown in  FIGS. 9, 14 ,  15 ,  16 , several fluid communication ports  632 ,  636  are provided, each port being both an input and an exit/output port. In the specific embodiment shown, one fluid communication port  632  may be utilized for inputting and outputting a biological cell material and the other port  636  might be utilized for inputting/outputting a processing fluid (e.g. buffer or enzyme containing aqueous solution). The ports  632 ,  636  may be sealably connected to a fluid management apparatus as discussed with reference to  FIG. 1 , wherein a series of valves are utilized to separately enable flow into, out of or through one port or another at any given time. The input/output ports  632 ,  636  of the enclosure  604  sealably communicate with the interior of enclosure  604  via the assembly and fastening together of rotating seal components  630  (body),  610  (upper seal),  620  (lower seal),  670  (header clamp),  680  (base),  681  (plug),  FIGS. 14-16  together with bag/enclosure  604  so as to provide several sealed fluid communication ports  632 ,  636  into and out of the interior  426  of the enclosure  604 ,  FIG. 9 . Another channel  634  as shown is provided in the rotating seal components  630  and  610 ,  FIGS. 14, 16  for input of sterile gas between and around the undersurface  612  and upper surface  622  of seal components  610 ,  620  which mate and rotate with respect to each other.  
      Most preferably, when biological cells are input into enclosure  604  together with a selected processing fluid having a predetermined composition, the ratio of the amount of biological cells and processing fluid is maintained constant between any two or more processing cycles, i.e., the processing conditions to which any two separate aliquots of biological cells are subjected is identical as between separate processing cycles.  
      As can be readily imagined, the volume of fluid input into the processing enclosure  604  at the beginning of any particular processing cycle may be selectively varied, (i.e., the processing enclosure  604  may be filled anywhere from 0-100% of its volume capacity), with the remaining unoccupied volume of the processing chamber  421  being selectively filled up by inputting or pumping in an appropriate amount of expressor fluid into enclosure  420 . Most preferably, the maximum volume or capacity of the processing enclosure  604  is approximately equal to or slightly less than the volume of the chamber  421 . As described above, the hinged doors  415  are pivotable  490 ,  FIG. 7  between open and closed positions, the doors  415  being shown in the closed position in  FIGS. 7-9 . When the doors are opened, the bag enclosure  604  is insertable into chamber  421  and when the doors are closed as shown in  FIG. 7-9 , the bag/enclosure  604  is firmly held within the volume of chamber  421 . The doors are lockable into the closed position shown in  FIGS. 7-9  by conventional means such as via spring based hinges  492  or other conventional means such as clasps, clamps or the like. The undersurface  494  of door retains the bag/enclosure  604  within chamber  421  and provides a stationary surface against which the bag/enclosure  604  engages and thereby is forced to compress under the opposing pressure exerted by the flexible membrane  411  on the flexible wall of the bag/enclosure  604  when the space  420  is expanding as described for example above the reference to  FIGS. 10, 11 . Suitable alternative mechanisms to doors  415  may comprise, for example, a plate or disc which is slidable into a stationary position equivalent to the closed position of doors  415 ,  FIGS. 7-9 .  
      The apparatus includes a sensor for monitoring the temperature of the fluids disposed in the processing enclosure  604 . In a preferred embodiment, the temperature sensor comprises an infrared IR thermocouple  406 ,  FIG. 5 , which detects IR radiation in a range of about 2 μm to 10 μm emitted through an IR transparent window disposed over the bag/enclosure  604 . The transparent window typically comprises ZnSe and is coated by a 0.5 mill layer of parylene N. The parylene N coating is used to protect the transparent window although it has some absorption of the IR radiation. Other conventional temperature sensors may also be employed.  
      In the disclosed embodiment, the IR thermocouple (e.g. IR t/c.03-J-80F/27C may be Exergen, Corp., 51 Water Street, Watertown, Mass. 02172) integrates the detected IR energy to determine the temperature of the fluids. This temperature is corrected for the local air temperature or ambient temperature between the transparent window and processing enclosure  604 . This air temperature is measured by a second temperature sensor that is a Si diode temperature sensor. The data from the Si diode is used for correcting the IR data.  
      Most preferably, the temperature of the fluids disposed in the processing enclosure  604  is controlled by controlling the temperature of the expressor fluid which is input into the expressor chamber/space  420 . Preferably, the source of expressor fluid  425 ,  FIGS. 7-9 ,  12  which is pumped via pump  502  into annular space  458 ,  FIG. 12  and through channel  416  and ultimately into chamber space  420 , is connected to a fluid heating and/or cooling device  506 ,  FIGS. 7-9 ,  12  which is controlled by a heating and/or cooling controller  504 . The expresser fluid is typically circulated through a reservoir, within which, the fluid is in thermal contact with certain devices that transfer thermal energy to or from the fluid in response to a control algorithm. These thermal devices may include Peltier Devices, electric resistance submersion heaters, air cooled radiators, or other similar devices or some combination of these types of thermal transfer devices. The expressor fluid which travels through channel  416  and grooves  410  makes contact with the surfaces of rotor or chuck  408  and the membrane  411  and the shafts  450 ,  455 . Rotor  408  and shafts  450 ,  455  are typically comprised of a heat conductive material such as metal (e.g. steel, iron, copper, aluminum or the like) and are thus readily heated or cooled to the temperature of the expressor fluid with which they are in contact. The temperature of the expressor fluid is thus readily conducted to the fluids disposed in the processing bag/enclosure  604  via the rotor  408 , shafts  450 ,  455  and through the flexible membrane  411  with which the flexible wall of the bag/enclosure  604  makes contact within chamber  421 . Thus, by controlling the temperature of the external source  425  of expressor fluid, the temperature of the entire processing system, including the interior chamber  421 , may be controlled.  
      The temperature of the fluid being monitored by sensor  406  may be input to a program or circuit  508  connected to controller  504 , FIGS.  4 ,  7 - 9 ,  12 . The program or circuit  508  preferably includes a subroutine for automatically directing the temperature controller to heat or cool the temperature of the expresser fluid source  425  to a predetermined constant temperature or series of temperatures over a predetermined period of time. The program  508  preferably includes a predetermined algorithm which uses the temperature information signal which is input from sensor  406  to direct control of the temperature controller  504  and heater and/or cooler element  506  such that the temperature of the external source  425  of expressor fluid is varied depending on the temperature signal input from sensor  406 . In one embodiment of the invention, the temperature of the source  425  may be cooled by simply terminating heating of the expresser fluid  425  thus allowing the fluids  425  to passively cool by self-radiation of heat rather than by proactive cooling.