System and method for collecting increased volume of IgG during plasma collection procedure

Abstract

To provide a system and a method for optimization of the volume of IgG during a plasmapheresis procedure.SOLUTION: A plasmapheresis system and a method for operating the plasmapheresis system are provided by which a reservoir 32 for concentrated red blood cells (RCC) has a first chamber for receiving anticoagulant used for priming a separator 14 and purging the system of air prior to a first draw cycle, and a second chamber for receiving separated red blood cells. Since the entire volume of the second chamber of the RCC reservoir receives separated red blood cells and no AC prime volume, a greater amount of whole blood may be processed in the first draw cycle, thus resulting in a greater total volume of Immunoglobulin G (IgG) being collected during the plasmapheresis procedure.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] This application relates to systems and methods for performing plasma exchange, and more specifically, to systems and methods for plasma exchange in which the volume of immunoglobulin G collected during the procedure is increased.

[0002] Plasma exchange is an apheresis procedure in which whole blood is removed from a donor, the plasma is separated from the cellular blood components (red blood cells, platelets, and white blood cells) and retained, and the cellular blood components are returned to the donor. Separation of the plasma from the cellular components is typically accomplished by an automated procedure using centrifugation or membrane filtration.

[0003] Plasma-derived therapies are provided through large-scale plasma fractionation facilities where many plasma donations are pooled together and then fractionated into their therapeutic components. Worldwide, there is a growing need for plasma-derived therapies, particularly immunoglobulin G (IgG). IgG has multiple indications when used intravenously or subcutaneously, such as in primary immunodeficiency disorders, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, and secondary immunodeficiency disorders.

[0004] In automated plasma exchange procedures, plasma products are often collected in multiple collection and reinfusion cycles until the total target volume of anticoagulated plasma is collected. According to recent literature, the donor's blood IgG concentration decreases throughout the plasma collection procedure, with the greatest decline shown after the first 200 mL of plasma collection. Specifically, a 9% decrease in the donor's IgG occurs as the collected plasma goes from a zero baseline (at the start of the procedure) to 200 mL of collected plasma, and an additional 4% decrease occurs from 200 mL to 800 mL of collection. See, for example, immunoglobulin G levels during large plasma collections for fractionation (Burkhardt et al., Transfusion 2017;56:417-420). This was due to an interstitial fluid shift equal to approximately 9% of the donor's initial total blood volume (after collecting 200 mL of plasma) to approximately 13% of the donor's initial total blood volume (after collecting 800 mL of plasma).

[0005] Since source plasma from multiple donors is combined, even a small increase in the volume collected from an individual donor, when added together, has a meaningful effect on the total volume of IgG in the pooled plasma; therefore, it is important to maximize the volume of IgG that can be collected from each individual donor. If a system and method are developed that can maximize the volume of IgG collected during the first aspiration cycle of a plasma exchange procedure, more IgG can be collected from each donor, and the total volume of IgG produced at each plasma collection center will increase. Accordingly, this disclosure provides a system and method for optimizing the volume of IgG during a plasma exchange procedure. [Overview of the project]

[0006] This disclosure provides a system and method for operating a plasma exchange system, which results in an increase in the volume of IgG collected by increasing the volume of whole blood processed in a first collection cycle.

[0007] In a first embodiment, a method is provided for performing a plasma exchange procedure having a priming step, at least one collection step, and at least one reinfusion step, to maximize the volume of whole blood processed during a first aspiration step. The method comprises: a) providing a disposable fluid flow set having a plurality of tubular segments in fluid communication with a reservoir having a first chamber into which a priming fluid flows during the priming step and a second chamber into which a cell fraction containing separated blood cells flows and from which the separated blood cells flow out during the reinfusion step; b) introducing the priming fluid into the disposable fluid flow set; c) flowing the used priming fluid into the first chamber of the reservoir; and d) occluding one or more tubular segments to prevent inflow into or outflow from the first chamber.

[0008] In a second embodiment, the method further includes: a) introducing whole blood into a disposable fluid flow set; b) separating the whole blood into a plasma fraction and a cell fraction; c) flowing the cell fraction into a second chamber of the storage unit.

[0009] In a third embodiment, the method further includes draining the cell fraction from a second chamber.

[0010] In a fourth aspect, the method further includes retaining the used priming fluid in a first chamber of the storage unit and disposing of it together with the disposable fluid flow circuit upon completion of the plasma exchange procedure.

[0011] In the fifth embodiment, the priming solution is an anticoagulant solution.

[0012] In a sixth embodiment, a disposable fluid flow set for an apheresis system includes a separator, a first pipe segment connected to the outlet of the separator, a second pipe segment, a first internal chamber, and a second internal chamber, each chamber comprising a reservoir having a first port in fluid communication with the first pipe segment and a second port in fluid communication with the second pipe segment.

[0013] In the seventh embodiment, the disposable fluid flow set further comprises a third pipe segment connecting a first port of a first internal chamber to a first pipe segment, a fourth pipe segment connecting a second port of the first internal chamber to a second port, a fifth pipe segment connecting a first port of a second internal chamber to the first pipe segment, and a sixth pipe segment connecting a second port of a second internal chamber to a second pipe segment.

[0014] In the eighth embodiment, the first internal chamber has an open upper end that allows fluid from the first internal chamber to spill into the second internal chamber.

[0015] In the ninth aspect, a system is provided for performing a plasma exchange procedure, comprising a durable hardware component and a disposable fluid flow set of any of the sixth to eighth aspects described above. The durable hardware component comprises a first double-tube clamp for controlling flow through a third and fifth tubing segment, a second double-tube clamp for controlling flow through a fourth and sixth tubing segment, and a programmable control unit programmed to automatically actuate the first and second double-tube clamps to selectively allow or inhibit flow through the third, fourth, fifth, and sixth tubing segments in connection with performing a priming, collection, or reinfusion stage of a plasma exchange procedure.

[0016] In a tenth embodiment, a fluid vessel is provided which includes a first internal chamber and a second internal chamber, each having a first port and a second port, the first internal chamber having an open upper end that allows fluid from the first internal chamber to overflow into the second internal chamber. [Brief explanation of the drawing]

[0017] [Figure 1] Figure 1 is a perspective view of an exemplary plasma exchange device suitable for use in the system and method of this application.

[0018] [Figure 2] Figure 2 is a perspective view of a rotating membrane separator of the type incorporated into a disposable set usable in the plasma exchange system shown in Figure 2, with parts cropped to show details.

[0019] [Figure 3] Figure 3 is a perspective view of the front panel of the plasma exchange system shown in Figure 2, and shows the components of the disposable set attached thereto.

[0020] [Figure 4] Figure 4 is a schematic diagram showing the operation of the plasma exchange system during the priming phase.

[0021] [Figure 5] Figure 5 is a schematic diagram showing the operation of the plasma exchange system in the collection stage.

[0022] [Figure 6] Figure 6 is a schematic diagram showing the operation of the plasma exchange system in the return stage or reinfusion stage.

[0023] [Figure 7] Figure 7 sequentially illustrates the flow to the RCC collection container according to the present disclosure during AC priming, during the first suction stage, during the first RCC return / reinfusion stage, and after the first RCC return / reinfusion stage followed by a subsequent suction stage or the end of the procedure.

[0024] [Figure 8] Figures 8a to 8c are perspective view, side view, and front view of the RCC collection container according to the present disclosure.

[0025] [Figure 9] Figures 9a to 9c are cross-sectional views showing details regarding the inside of the RCC collection container. Figure 9a is a perspective view in which a vertical cross-section is taken behind the front wall of the RCC collection container. Figure 9b is a perspective view in which a vertical cross-section is taken behind the front wall of the AC chamber. Figure 9c is a top view.

[0026] [Figure 10] Figure 10 is a perspective view of a combination of the RCC collection container, related pipe segments connected to the AC chamber and the RCC chamber, and a双联管 clamp related to the pipe segments.

Mode for Carrying Out the Invention

[0027] A more detailed description of the systems and methods described herein is provided below. It should be understood that the following descriptions of specific apparatuses and methods are illustrative and do not encompass all possible variations or applications. Therefore, the scope of this disclosure should be understood to include, and not to be limiting, any variations or embodiments that may arise for a person of ordinary skill.

[0028] This disclosure provides a system and method for increasing the volume of IgG collected in a plasma exchange procedure by manipulating a plasma exchange system to increase the volume of whole blood processed in a first collection cycle. The amount of extracorporeal blood that can be processed in a single collection cycle is limited by the capacity of the reservoir for receiving separated red blood cells ("red blood cell concentrate" or RCC). Since a volume of anticoagulant (AC), used for priming and flushing air out of the disposable set before introducing blood into the disposable set, is received in the RCC reservoir, the volume of extracorporeal blood that can be processed in the first aspiration cycle is reduced by the volume of that AC.

[0029] This disclosure increases the amount of extracorporeal blood that can be processed in the first aspiration cycle by providing the RCC reservoir with an AC prime volume and a separate chamber for receiving separated red blood cells. The contents of the RCC chamber are returned to the donor after the completion of each collection stage, while the AC prime volume is maintained in the AC chamber throughout the procedure and discarded along with the disposable kit after the procedure is complete and the connection with the donor is severed.

[0030] As further described herein, each AC chamber and RCC chamber has two ports with associated tubular segments. A first pair of tubular segments, each containing one tubular segment from the AC chamber and RCC chamber, is connected to the cell line of the disposable set, while a second pair of tubular segments, each containing one tubular segment from the AC chamber and RCC chamber, is connected to the reinfusion line of the disposable set.

[0031] The system's hardware components include two double-tube clamps, one acting on each pair of tubular segments, alternating between allowing flow through one pair and preventing flow through the other, or preventing flow through both tubular segments of a pair. During AC priming, the two double-tube clamps direct the flow to the AC chamber in the RCC reservoir, and then during plasma collection, the clamps direct the flow of separated red blood cells to the RCC chamber in the RCC reservoir. This allows the entire extracorporeal blood volume to be processed in the first collection cycle, when the donor's IgG concentration is highest, resulting in the collection of additional IgG for the procedure.

[0032] Now looking at the attached diagrams, plasma exchange is performed to collect plasma to be processed as source plasma in an automated system that includes hardware components, generally indicated by reference numeral 10 (most commonly seen in Figure 1), and disposable sets, generally indicated by reference numeral 12 (most commonly seen in Figures 3-6, where the disposable sets are shown attached to the hardware components). Referring to Figures 1-6, and as will be described in more detail below, the disposable set 12 consists of integrally connected separators, containers, and tubing for transporting blood and solutions within a sterile fluid pathway.

[0033] The most commonly seen separator 14 in Figure 2 has a rotating membrane filter 16 mounted on a rotor 18 to rotate within a case 20 to separate blood into its components. A detailed description of the rotating membrane separator is provided in U.S. Patent No. 5,194,145 by Schöndorfer, incorporated herein by reference. As can be understood, in different systems, the separation of whole blood can be achieved by centrifugation. See, for example, U.S. Patent No. 5,360,542 by Williamson et al.

[0034] During plasma exchange, anticoagulated whole blood enters the separator 14 through the whole blood input port 22. The plasma is separated by a rotating membrane filter and then exits the plasma output port 24, passes through the plasma line 26, and enters the plasma collection container 28. The concentrated cells are pumped from the concentrated cell output port 30 to the RCC storage unit 32 (described in more detail below), where the cells remain until reinfusion to the donor.

[0035] The disposable set 12 also includes a tubular line (donor line 34 ending with a venipuncture needle 36) for introducing whole blood from the donor into the system during collection and returning concentrated cells to the donor during reinfusion, a tubular line (blood line 38) for transporting anticoagulated whole blood to the separator, a tubular line (cell line 40) for transporting concentrated cells to the reservoir, a tubular line (reinfusion line 42) for transporting concentrated cells from the reservoir to the donor line, a tubular line (plasma line 44) for transporting plasma to the plasma collection container, a tubular line (saline line 46) for transporting saline, and a tubular line (AC line 48) for transporting anticoagulant.

[0036] The hardware component 10 includes a programmable control unit 50 and a touchscreen 52 with a graphical user interface ("GUI") for the operator to control the procedure. For example, the GUI allows input of either the donor ID, donor sex, donor height, donor weight, donor age, donor hematocrit / hemoglobin value, target saline infusion volume (if a saline protocol is selected), and target plasma volume. The touchscreen 52 also allows the operator to collect status information and handle error conditions.

[0037] Three peristaltic pumps, including an AC pump 54, a blood pump 56, and a cell pump 58, are located on the front panel of the hardware component 10. The AC pump 54 delivers anticoagulant solution (AC) to the blood line 38 at a controlled rate as whole blood enters the set from the donor. The blood pump 56 delivers anticoagulated whole blood to the separator during the collection phase of the procedure and returns concentrated cellular components and, if necessary, replacement fluid to the donor during the reinfusion phase of the procedure. The cell pump 58 delivers concentrated cellular components from the separator 14 to the storage unit during the collection phase.

[0038] The front panel also includes four clamps to which various tubes of the disposable set 12 are attached, including a reinfusion clamp 60, a blood clamp 62, a saline clamp 64, and a plasma clamp 66. The reinfusion clamp 60 closes to shut off the reinfusion line (42) during the collection phase (Figure 5) and opens during the reinfusion phase (Figure 6) to allow the blood pump 56 to reinfuse concentrated cellular components from the reservoir 32 to the donor. The blood clamp 62 opens during the collection phase to allow anticoagulated whole blood to be pumped to the separator 14 and closes during the reinfusion phase to shut off the blood line 38. The saline clamp 64 closes to shut off the saline line 46 during the collection phase and during the reinfusion of separated cellular components. If saline is used as replacement fluid, the saline clamp 64 opens during the reinfusion phase. The plasma clamp 66 opens during the collection phase to allow plasma to flow into the plasma collection container 28 and closes during the reinfusion phase. As will be explained in more detail below, the reinjection clamp 60 is a double-tube clamp, and the second double-tube clamp 104 is associated with the cell line 40 that leads to the inlet of the RCC reservoir 32.

[0039] Referring to Figure 1, the hardware component 10 includes three weighing scales for monitoring the current plasma collection volume (scale 68), AC solution volume (scale 70), and concentrated cell contents volume (scale 72). The system also includes various sensors and detectors, including a venous pressure sensor 74, a separator pressure sensor 76, an optical blood detector 78, and an air detector 80.

[0040] In accordance with the present disclosure, the RCC reservoir 32 comprises a separate AC chamber 82 for receiving an AC prime volume and a separate RCC chamber 84 for receiving separated red blood cells. The size and capacity of the RCC reservoir are limited by regulations regarding the permissible extracorporeal volume of body fluid drawn from the donor. As a result, the separate AC chamber allows the RCC chamber to be brought to its maximum permissible size and volume, and a certain volume of blood can be separated in the first aspiration cycle, so that the entire volume of the RCC chamber is filled with separated red blood cells.

[0041] The AC chamber 82 is open at its upper end 86, and as a result, additional AC prime volume due to an alarm or error may spill over the top of the AC chamber 82 into the RCC chamber 84. The AC chamber 82 includes two ports 88, 90 at its lower end, each having an associated tubular segment. Tubular segment 92 is associated with port 88 and is in fluid communication with the cell line 40, while tubular segment 94 is associated with port 90 and is in fluid communication with the reinjection line 42. Similarly, the RCC chamber includes two ports 96, 98 at its lower end, each having an associated tubular segment. Tubular segment 100 is associated with port 96 and is in fluid communication with the cell line 40, while tubular segment 102 is associated with port 98 and is in fluid communication with the reinjection line 42. Therefore, tube segments 92,100 form a first pair of tube segments connected to the cell line 40 (for example, by a Y connector), and tube segments 94,102 form a second pair of tube segments connected to the reinjection line 42 (also, for example, by a Y connector).

[0042] The system's hardware components include two double-tube clamps, one for each pair of tubular segments, which act on each pair of tubular segments to alternately allow flow through one pair and block flow through the other pair, or prevent flow through both tubular segments of the pair. Specifically, the reinfusion clamp 60 described above is a double-tube clamp that acts on tubular segments 94,102 to control flow through the reinfusion line 42. A second double-tube clamp 104 is provided that acts on tubular segments 92,100 to control flow through the cell line 40. During AC priming, the two double-tube clamps direct flow into the AC chamber in the RCC reservoir, and then during plasma collection, the clamps direct flow of separated red blood cells into the RCC chamber in the RCC reservoir. To understand this, the control unit can be pre-programmed to automatically activate the double-tube clamps to control flow through the relevant tubular segments for the execution of the priming, collection, and return stages of the plasma exchange procedure, as described below.

[0043] The donor is connected to the system throughout the procedure. As illustrated, the disposable set 12 includes a single venipuncture needle 36 through which whole blood is drawn from the donor during the collection phase (Figure 5), and concentrated cells are returned to the donor during the reinfusion phase (Figure 6). As described above, the plasma exchange procedure may consist of multiple cycles, each having a collection / separation phase followed by a return or reinfusion phase.

[0044] Prior to the first collection phase, the disposable set is primed with AC and air is bled from the set. During the collection phase, whole blood is separated into plasma and concentrated cells; the separated plasma is directed to the plasma collection container 28, and the separated red blood cells are directed to the storage unit 32. During the reinfusion phase, the concentrated red blood cells from the storage unit 32 are reinfused to the donor via the venipuncture needle 36.

[0045] As shown in Figures 4 and 7, during the priming phase, the anticoagulant solution (AC) is pumped at a controlled rate through a disposable set to prime the separator 14 and purge air from the disposable set. The double-tube clamp 104 is operated to allow flow through tube segment 92 to the AC chamber 82 but to block flow through tube segment 100 to the RCC chamber 84. The double-tube clamp 104 is operated to allow flow through tube segment 94 to the AC chamber but to block flow from tube segment 102 to the RCC chamber. This allows the initial AC prime volume to fill the AC chamber 82 (106 in Figure 7). Figure 4 shows a double pipe clamp 60 that blocks the flow from pipe segment 94 to the AC chamber and the flow from pipe segment 102 to the RCC chamber during the first state of the priming phase, while 106 in Figure 7 shows the flow through both pipe segments 92,94 to the AC chamber during the final state of the priming phase, so that both lines to the reservoir 32 are flowed with AC to remove air from the fluid path.

[0046] As shown in Figures 5 and 7, during the collection phase, AC is pumped at a controlled rate and mixed with whole blood upon entering the disposable set 12. The anticoagulant blood is pumped to the separator 14, where the plasma is separated from the cellular components and directed towards the plasma collection container 28. A double-tube clamp 104 is operated to allow flow through tube segment 100 to the RCC chamber but block flow through tube segment 92 to the AC chamber, while a double-tube clamp 60 is operated to block flow from the AC chamber 82 through tube segment 94 and flow from the RCC chamber 84 through tube segment 102. Thus, the separated red blood cells are pumped from the separator 14 to the RCC chamber 84 of the storage unit 32 (108 in Figure 7). When the storage unit 32 reaches the expected volume of separated red blood cells, the collection phase is stopped.

[0047] Referring to Figures 6 and 7, during the reinfusion phase, the blood pump 56 reverses direction and pumps concentrated cells from the RCC chamber 84 of the reservoir 32 to the donor via the reinfusion line 34 and back to the apheresis needle 36. The double-tube clamp 104 is operated to prevent flow through both the tubing segment 92 leading to the AC reservoir and the tubing segment 100 leading to the RCC chamber, while the double-tube clamp 60 is operated to allow flow from the RCC chamber 84 via tubing segment 102 and prevent outflow from the AC chamber 82 via tubing segment 94 (110 in Figure 7). After the RCC has been returned to the donor, the double-tube clamp 60 is operated to occlude both tubing segments 94 and 102 (112 in Figure 7). The system then proceeds to the next aspiration cycle or terminates the procedure (114 in Figure 7). As can be understood, the AC prime volume is maintained within the AC chamber 82 throughout the procedure and is not returned to the donor. If a saline protocol is selected in which saline is returned to the donor as a substitute for the collected plasma, saline infusion follows the final reinfusion stage.

[0048] The advantages of the above system and method in achieving an increase in the volume of collected IgG can be seen in the following examples.

[0049] Example 1. In the system of this example, the AC prime volume (prime volume) is approximately 30 mL. The RCC collection container has a separate AC chamber with a capacity of approximately 30 mL, and the capacity of the RCC chamber is 250 mL, so a total volume of 250 mL of blood can be processed in the first collection cycle. This is more than the 220 mL when the 30 mL AC prime volume and separated red blood cells are combined in the RCC collection container. With an additional 30 mL of separated red blood cells processed with a 75% collection efficiency in the first collection cycle, if the donor's hematocrit value is 40, the 54 mL of processed additional blood contains 32.4 mL of processed additional plasma (54 mL × 0.6 = 32.4 mL). The 42.4 mL of additional plasma processed with a 75% collection efficiency produces 24.3 mL of additional plasma collected in the first collection cycle (42.4 mL × 0.75 = 24.3 mL). The RCC collection container received an additional 29.7 mL of RCC (54 mL - 24.3 mL), of which 8.1 mL was plasma (32.4 mL - 24.3 mL), resulting in a hematocrit value of 73% for the additional 29.7 mL of RCC. The additional 24.3 mL of plasma collected in this first cycle showed an increased concentration of 67 mg / dL IgG compared to the second collection cycle (Burkhardt et al., 2017), and an increased collection of 16.3 mg of IgG per collection (24.3 mL × 67 mg / dL).

[0050] Example 2. In the system of this example, the AC prime volume (prime volume) is approximately 10 mL. The RCC collection container has a separate AC chamber with a capacity of approximately 10 mL, and the capacity of the RCC chamber is 200 mL, so the total volume of blood, 200 mL, can be processed in the first collection cycle. This is more than the 190 mL when the 10 mL AC prime volume and separated red blood cells are combined in the RCC collection container. With an additional 10 mL of separated red blood cells processed with a collection efficiency of 75% in the first collection cycle, if the donor's hematocrit value is 40, the additional blood processed will contain 10.8 mL of processed additional plasma (18 mL × 0.6 = 10.8 mL). The 10.8 mL of additional plasma processed with a collection efficiency of 75% will produce 8.1 mL of additional plasma collected in the first collection cycle (10.8 mL × 0.75 = 8.1 mL). The RCC collection container received an additional 9.9 mL of RCC (18 mL - 8.1 mL), of which 2.7 mL was plasma (10.8 mL - 8.1 mL), resulting in a hematocrit value of 73% for the additional 9.9 mL of RCC. The additional 8.1 mL of plasma collected in this first cycle showed an increased concentration of 67 mg / dL IgG compared to the second collection cycle (Burkhardt et al., 2017), and an increased collection of 5.4 mg IgG per collection (8.1 mL × 67 mg / dL).

[0051] The above methods and systems have several embodiments. In a first embodiment, a method for collecting plasma is provided, wherein plasma products are collected in multiple collection steps, and the red blood cells separated in between are reinjected into the donor.

[0052] The embodiments described herein will be understood to be illustrative of some applications of the principles of this subject matter. Numerous modifications can be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including combinations of features individually disclosed or claimed herein. For these reasons, the claims are not limited to the above description but are set forth in the following claims.

Claims

1. A method by which a control unit operates a system for performing a plasma exchange procedure to maximize the volume of whole blood processed during a first aspiration step, the system comprising a priming step, at least one collection step, and at least one reinfusion step, The aforementioned system, A disposable fluid flow set having a plurality of tube segments in fluid communication with a storage section comprising a first chamber into which priming fluid flows during the priming stage, and a second chamber into which cell fractions containing blood cells separated during the collection stage flow and from which blood cells separated during the reinjection stage flow out, The hardware components include a control unit, a separator, a first clamp, a second clamp, and at least a first pump. The disposable fluid flow set is attached to the hardware component, The control unit is configured to automatically perform at least the priming step, the at least one collection step, and the at least one reinjection step. The aforementioned method, a) The control unit operates the first pump to flow the priming fluid, thereby automatically introducing the priming fluid into the disposable fluid flow set. b) The control unit operates the first clamp to allow the flow of the priming fluid into the first chamber of the storage unit and to prevent the flow of the priming fluid into the second chamber, thereby automatically draining the used priming fluid into the first chamber of the storage unit. c) The control unit automatically closes one or more of the pipe segments to prevent flow in and out of the first chamber by operating the first clamp to prevent the flow of fluid into the first chamber and operating the second clamp to prevent the flow of fluid out of the first chamber, d) A method comprising the use of priming fluid being retained in the first chamber of the reservoir and discarded together with the disposable fluid flow circuit upon completion of the plasma exchange procedure.

2. The method according to claim 1, further comprising: a) the control unit automatically introducing whole blood into the disposable fluid flow set by operating the second clamp to prevent the flow of fluid from the storage unit; b) the control unit automatically separating the whole blood into a plasma fraction and a cell fraction by operating the separator; and c) the control unit automatically flowing the cell fraction into the second chamber of the storage unit by operating the first clamp to allow the flow of fluid into the second chamber and prevent the flow of fluid into the first chamber.

3. The method according to claim 2, further comprising the control unit automatically draining the cell fraction out of the second chamber by operating the second clamp to allow the flow of fluid from the second chamber and to prevent the flow of fluid from the first chamber.

4. The method according to claim 3, wherein the priming fluid is an anticoagulant solution.

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