Blood component sampling cassette, blood sampling circuit set, and blood component sampling system

This application is a broadening reissue of U.S. Pat. No. 11,752,243, which was assigned U.S. patent application Ser. No. 16/332,473 and filed Mar. 12, 2019, which is a national stage application under 35 U.S.C. 371 and claims the benefit of PCT Application No. PCT/JP2017/032886 having an international filing date of Sep. 12, 2017, which designated the United States, which PCT application claimed the benefit of Japanese Patent Application No. 2016-179107, filed Sep. 14, 2016, the disclosures of which are incorporated herein by reference in their entirety.

The present disclosure relates to a biological component sampling cassette attached to a separation device configured to separate a biological component from liquid containing at least one biological component. Specifically, the present disclosure relates to a blood component sampling cassette attached to a blood component separation device, a blood sampling circuit set, and a blood component sampling system.

In recent blood donation, blood component sampling (apheresis) with a less burden on a blood donor body has been performed in addition to whole blood sampling for sampling whole blood from a blood donor. Blood component sampling is a blood sampling method using a blood component sampling system (an apheresis system) to sample only specific blood components from the whole blood and return the remaining components to the body of the blood donor.

Patent Document 1 discloses a blood component sampling system configured to centrifuge whole blood extracted from a blood donor to sample platelet. This blood component sampling system includes a blood sampling circuit set forming a circuit in which blood or blood components to be processed flow, and a centrifuge (a blood component separation device) attached to the blood sampling circuit set. The blood sampling circuit set includes a blood sampling line having a blood sampling needle, a band-shaped channel (a separator) to which the whole blood is introduced, a plurality of bags configured to contain the blood components and the like, and a cassette connected to these elements through a plurality of tubes. The cassette is provided with a plurality of flow paths including, for example, a line for introducing the blood from the blood donor, a line for transferring the blood component to each bag, and a retransfusion line for returning, to the blood donor, the blood components not to be sampled. Upon use, the cassette is attached to an attachment section provided at the blood component separation device.

A typical cassette has been made of hard resin, such as PET, not resistant to high heat in autoclave sterilization (so-called heat sterilization), and therefore, EOG sterilization has been performed as sterilization processing in manufacturing. EOG sterilization has problems such as great care and a high cost for sterilization for reasons such as that special processing gas is needed as compared to autoclave sterilization. Moreover, the typical cassette has been molded by a large-scale injection molding method, leading to a problem such as a high manufacturing cost.

The present disclosure has been made in view of the above-described problems, and an object of the present invention is to provide a blood component sampling cassette which can be more efficiently manufactured at lower cost as compared to a typical cassette, a blood sampling circuit set, a blood component sampling system.

For accomplishing the above-described object, the present disclosure relates to a biological component sampling cassette including a cassette main body provided with a plurality of flow paths and configured to be attachable to a separation device configured to separate a biological component from liquid containing at least one biological component. The cassette main body is made of a soft material to which heat sterilization is applicable. The plurality of flow paths include an introduction line configured to introduce the liquid, a biological component transfer line configured to transfer, to a sampling container, the biological component obtained by separation processing of the liquid, and a return line configured to transfer liquid other than the biological component obtained by the separation processing. The return line is provided with a reservoir configured to temporarily store the liquid to be returned. The reservoir is configured to be expandable/contractable, and is pressed by a return pump provided at the separation device to discharge the liquid from the reservoir. Moreover, the biological component is blood or a cultured or sampled cell.

According to the biological component sampling cassette of the present disclosure having the above-described configuration, easier autoclave sterilization as compared to other types of sterilization processing (e.g., EOG sterilization) is applicable as sterilization processing upon manufacturing, leading to efficient manufacturing. Further, the cassette main body is made of the soft material, and therefore, the cassette can be manufactured at lower cost as compared to the typical cassette made of the hard resin by large-scale injection molding. Further, the cassette main body is provided with the reservoir pressed by the return pump of the separation device to discharge the liquid. Thus, in the separation device, it is not necessary to separately ensure a location for disposing the reservoir and a location for providing the pump, and therefore, device layout simplification and compactification are easily realized.

In the above-described biological component sampling cassette, the cassette main body may have a sensor pressing section configured to press a reservoir pressure sensor equipped at the separation device, thereby detecting an inner pressure of the reservoir.

Thus, the inner pressure of the reservoir can be detected with a simple configuration.

In the above-described biological component sampling cassette, the sensor pressing section may be provided at the return line.

Thus, the inner pressure of the reservoir can be more precisely detected.

In the above-described biological component sampling cassette, the reservoir may be expanded in a normal state.

Thus, a desired reservoir capacity can be easily ensured.

Moreover, the present disclosure relates to a biological component sampling circuit set including a biological component sampling cassette having a cassette main body provided with a plurality of flow paths and configured to be attachable to a separation device configured to separate a biological component from liquid containing at least one biological component, a separation processing section connected to the biological component sampling cassette through a tube and having a processing chamber configured to separate the liquid into multiple biological components by actuation of the separation device, and a bag connected to the biological component sampling cassette through a tube. The cassette main body is made of a soft material to which heat sterilization is applicable. The plurality of flow paths include an introduction line configured to introduce the liquid, a biological component transfer line configured to transfer, to a sampling container, the biological component obtained by separation processing of the liquid, and a return line configured to transfer liquid other than the biological component obtained by the separation processing. The return line is provided with a reservoir configured to temporarily store the liquid to be returned. The reservoir is configured to be expandable/contractable, and is pressed by a return pump provided at the separation device to discharge the liquid from the reservoir.

According to the biological component sampling circuit set, the circuit set can be efficiently manufactured at low cost, and the device layout of the separation device can be simplified.

Further, the present disclosure relates to a biological component sampling system including a separation device configured to separate a biological component from liquid containing at least one biological component, and a biological component sampling cassette configured to be attachable to the separation device. The biological component sampling cassette includes a cassette main body provided with a plurality of flow paths. The cassette main body is made of a soft material to which heat sterilization is applicable. The plurality of flow paths include an introduction line configured to introduce the liquid, a biological component transfer line configured to transfer, to a sampling container, the biological component obtained by separation processing of the liquid, and a return line configured to transfer liquid other than the biological component obtained by the separation processing. The return line is provided with a reservoir configured to temporarily store the liquid to be returned. The reservoir is configured to be expandable/contractable, and is pressed by a return pump provided at the separation device to discharge the liquid from the reservoir.

According to the biological component sampling system, the biological component sampling system can be efficiently manufactured at low cost, and the device layout of the separation device can be simplified.

In the above-described biological component sampling system, the return pump equipped at the separation device may have a pressing plate configured to press the reservoir in a thickness direction.

By the return pump (a pressing plate type pump) having such a configuration, desired solution transfer performance (a flow rate) can be easily obtained.

In the above-described biological component sampling system, the separation device may include a reservoir pressure detection mechanism configured to detect the inner pressure of the reservoir, and a control section configured to control operation of the pump based on the pressure detected by the reservoir pressure detection mechanism.

With this configuration, a return speed (the flow rate) can be accurately controlled.

In the above-described biological component sampling system, the control section may control operation of the pump such that the inner pressure of the reservoir reaches a predetermined target pressure.

With this configuration, the return speed can be maintained substantially constant.

In the above-described biological component sampling system, the cassette main body may have a sensor pressing section configured to press the reservoir pressure detection mechanism.

According to the present disclosure, the cassette can be more efficiently manufactured at lower cost as compared to the typical cassette.

Multiple preferable embodiments of the present disclosure will be described below with reference to the attached drawings. Note that in a second embodiment, the same reference numerals are used to represent identical or similar elements to those of a first embodiment, and detailed description thereof will not be repeated.

In, a blood component sampling systemA is configured as a blood apheresis system, which continuously extracts blood (whole blood) from a blood donor to centrifuge the blood outside a body, thereby sampling specific blood components (platelet, red blood cells, plasma in the present embodiment) while returning, to the blood donor, blood components not to be sampled.

First, the blood component sampling systemA illustrated inwill be schematically described. This blood component sampling systemA includes a blood sampling circuit setconfigured to store and circulate the blood components, and a centrifuge(a blood component separation device) configured to apply centrifugal force to the blood sampling circuit set. The blood sampling circuit sethas a channel(a blood processing section) as a primary separator configured such that the whole blood extracted from the blood donor is introduced and centrifuged to the multiple blood components. The centrifugehas a rotorconfigured to apply the centrifugal force to the channel. An attachment grooveextending in a circumferential direction about the rotation axis “a” of the rotoris formed at an upper surfacea of the rotor, and the channelis attachable to the attachment groove.

Next, the blood sampling circuit setand the centrifugewill be described in detail.

The blood sampling circuit setis discarded after every use to prevent contamination and keep sanitation. The blood sampling circuit setincludes a blood sampling/retransfusion sectionhaving a blood sampling needle, the channel, a plurality of bags, and a blood component sampling cassette(hereinafter referred to as a “cassette”) connected to these elements through a plurality of tubes. The plurality of bagsincludes an ACD solution bag, an air bag, a platelet preservation solution bag, a PPP bag, a platelet bag, and a red blood cell bag.

The blood sampling/retransfusion sectionis connected to the ACD solution bagand the channelthrough the cassette. During use of the blood sampling circuit set, an ACD solution as an anticoagulant agent is, as default operation, supplied from the ACD solution bagto the channel, and in this manner, coagulation of the whole blood is suppressed.

The channelis connected to the cassettethrough a channel connection line. Meanwhile, the plurality of bagsare connected to the cassettethrough the plurality of tubes.

The channelis formed in a belt-shaped bag. The channelis attached to the attachment grooveformed at the rotorof the centrifuge, and is configured to allow introduction and flowing in/out of the blood. Further, the channelis a soft bag having, on the inside thereof, a first chamber(a processing chamber) to which the whole blood of the blood donor is supplied, and can be easily bent, folded, and rounded. The first chamberextends from one end portiona to another end portionb of the channel.

The one end portiona of the channelis coupled to an introduction tubeforming part of the channel connection line. The introduction tubeis connected to the cassette. During centrifugation processing, the whole blood introduced to the first chamberis centrifuged by the centrifugal force while circulating from the one end portiona to the other end portionb.

In blood component sampling by means of the blood sampling circuit set, the whole blood extracted from the blood donor through the blood sampling needleflows from the one end portiona connected to the introduction tubeto the first chamberof the channelattached to the attachment groove. The inflow whole blood circulates toward the other end portionb along an extension direction of the channel. The whole blood receives the centrifugal force accompanied by rotation of the rotor, and therefore, is centrifuged while circulating. In the case of the present embodiment, the whole blood is, by centrifugation, separated into plasma (platelet poor plasma: PPP) as a light specific gravity component (a supernatant component), red blood cells (concentrated red cells) as a heavy specific gravity component (a sedimentation component), and buffy coat (BC) as an intermediate specific gravity component.

The other end portionb of the channelis connected to first to third lead tubesa toc. The first lead tubea and the second lead tubeb are connected to the cassette. The red blood cells separated by centrifugation in the first chamberare introduced to the cassettethrough the first lead tubea. Further, the plasma generated in the first chamberis introduced to the cassettethrough the second lead tubeb.

The third lead tubec is connected to a concentratoras a secondary separator having a second chamber. The buffy coat generated in the first chamberby centrifugation of the whole blood is introduced to the concentratorthrough the third lead tubec. The buffy coat contains a white blood cell component and platelet-rich plasma (a platelet-containing component).

The concentratoris configured to introduce the buffy coat from the channelto the second chamberand further centrifuge the buffy coat by the centrifugal force accompanied by rotation of the rotor. This concentratoris formed in a conical shape with multiple steps. In a state in which the concentratoris attached to the rotor, a top side of the conical shape is disposed further from the centrifugal center, and a bottom side of the conical shape is disposed closer to the centrifugal center.

The concentratorseparates the buffy coat into white blood cells as a heavy specific gravity component and platelet as a light specific gravity component (more specifically, a platelet-containing component containing plasma and platelet). The white blood cells are captured by the multiple steps formed at the concentrator. The platelet flows out to a relay tubeconnected to an outlet (the bottom side) of the concentrator, and is introduced to the cassette.

Note that the introduction tube, the first lead tubea, the second lead tubeb, and the relay tubeare bundled by a bundling sheath. In the present embodiment, the channel connection lineincludes the introduction tube, the first to third lead tubesa toc, the concentrator, and the relay tube.

The ACD solution bagis a bag configured to contain the ACD solution as the anticoagulant agent, and is connected to the cassettethrough a tubea. The air bagis a bag configured to contain air discharged from a later-described reservoirat a later-described priming process in retransfusion processing, and is connected to the cassettethrough a tubeb.

The platelet preservation solution bagis a bag configured to contain a platelet preservation solution (a PAS solution), and is connected to the cassettethrough a tubec. The PPP bagis a bag configured to contain the plasma obtained by centrifugation, and is connected to the cassettethrough a tubed.

The platelet bagis a bag configured to contain the platelet obtained by centrifugation, and is connected to the cassettethrough a tubee. The red blood cell bagis a bag configured to contain the red blood cells obtained by centrifugation, and is connected to the cassettethrough a tubeh.

In, the cassetteincludes a cassette main bodyhaving a plurality of flow paths. The cassette main bodyhas a first sheetand a second sheet, these sheets being made of a soft material to which autoclave sterilization is applicable. The first sheetand the second sheetoverlap with each other in a thickness direction, and are bonded to each other.

The soft material which forms the first sheetand the second sheetand to which autoclave sterilization is applicable means that the soft material exhibits heat resistance against heat (e.g. 121° C.) of autoclave sterilization for equal to or longer than a predetermined period of time and exhibits water vapor permeability allowing introduction of water vapor as processing gas to the flow paths in the cassette. Such a soft material includes, for example, vinyl chloride and polyolefin.

The plurality of flow paths are formed between the first sheetand the second sheet. The way of bonding the first sheetand the second sheetincludes, for example, fusion (high-frequency fusion, thermal fusion, and the like) and adhesion. Further, the cassettehas a plurality of port membersarranged at a peripheral edge portion of the cassette main body, and tubes (the tubesand the like) are each connected to these port members.

As illustrated in, the plurality of flow paths formed at the cassette main bodyat least include an introduction lineconfigured to introduce the blood sampled from the blood donor, a blood component transfer lineconfigured to transfer, to sampling containers (the PPP bag, the platelet bag, the red blood cell bag), the blood components obtained by the processing of separating the blood, and a retransfusion lineconfigured to transfer, to the blood donor, the blood components not to be sampled. In the present embodiment, the plurality of flow paths further include an ACD solution lineconfigured to transfer the ACD solution to the blood sampling/retransfusion section.

An inflow side (a flow path elementa) of the introduction lineis connected to a tube of the blood sampling/retransfusion section. An outflow side (a flow path elementb) of the introduction lineis connected to the introduction tubeconnected to the channel. Thus, the blood sampling/retransfusion sectionand the channelare connected through the introduction line. Moreover, an expandable/contractable balloon sectionis provided on the introduction line. The balloon sectionis a portion configured to press a later-described centrifugal pressure sensor(see) provided at the centrifuge. The first sheetand the second sheetpartially form a wall of the balloon section. A lumen of the balloon sectioncommunicates with the flow path elementa and the flow path elementb.