JPS63150668A - Method and device for separating leukocyte from platelet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to -m for sealing against blood and blood components;
In particular, it relates to a mixture of white blood cells (WBC) and platelets, 'collected platelet containers designed specifically for the fine separation of unwanted white blood cells from the collected platelets.

Blood gold is separated into various components or sub-components, which are then divided into 1
It is well known to administer drugs to patients who are deficient in one or more components. It is well known that the main components of whole blood include red blood cells, white blood cells, platelets, and plasma, and that this plasma component is further separated into subcomponents that have therapeutic uses.

Whole blood is typically collected through conduits into a flexible plastic donor bag to which one or more auxiliary bags are connected. Typically, whole blood collected in a donor bag is centrifuged to obtain a lower layer of sedimented red blood cells and an upper layer of platelet-rich plasma. The platelet-rich plasma is then routed through the connecting conduit to the auxiliary bag. This is sequentially centrifuged and then centrifuged using known means (e.g. cohn).
) Separation of platelets from plasma which can be further separated into useful products by fractionation).

A blood bag designed to separate new red blood cells (neocytes) from old red blood cells (herocytes) was recently disclosed in US Pat. No. 4,416,778. The bag consists of two separate chambers connected by a conduit provided with valve means. There does not appear to be any suggestion in this patent that the chambers should be connected in series or that this type of device would be useful without intermediate valve means. Turner
), U.S. Pat.
A blood collection bag is shown that facilitates separation of plasma into the upper portion and platelets into the upper portion. The U.S. patent of Persiclsky et al. discloses an apparatus for the centrifugal separation of platelet-rich plasma, including the use of a B-B valve; however, to date, relatively simple and inexpensive devices have been developed. We do not know how to reliably separate WBCs (and any remaining RBCs) from other blood components, especially platelets, while using conventional separation techniques (eg, centrifugation).

Residual RBCs here refer to RBCs that remain in the platelet-rich plasma after the initial global separation of RBCs and plasma. These RBCs are carried along with platelets when they are separated from platelet-rich plasma.

The platelet content from a single blood donation is only a fraction (usually 1/6) of the amount used for administration in conventional therapy; for this reason, it is obtained from several supplementary bags. It is common practice to deliver platelets into one platelet collection bag that holds platelets from approximately six separate blood donations. Such a platelet collection bag is then used to administer the platelet concentrate directly to the patient.

It is known that when platelets are separated from platelet-rich plasma, white blood cells (WBCs) and sometimes residual RBCs are included as contaminants in the platelet concentrate. Obviously, it would be advantageous to exclude both RBC and WBC contaminants from platelet preparations. Additionally, the presence of leukocytes has been associated with febrile transfusion reactions and abnormal immune responses. For example, J.

G, E crn 1sse and A.
Brand (Brand)
p, I-1<em>otol , ), January 1981;
Please refer to the literature in Vol. 9, No. 1, pp. 77-83.
Although it is not common to carry out the step of separating BC from platelet concentrate and there are no simple, inexpensive commercially available products intended to do this, in cases where this is done (less than 10%) , the platelets in a standard platelet concentrate bag are simply centrifuged in a regular auxiliary bag, and the resulting WBC is compared to the top layer of incompatible platelets and the WB.
The lower layer of C is obtained. This separation technique was developed by R.H. He-rzig et al., Blood.
, Vol. 46, No. 5, pp. 743-749, November 1975, approximately 96% of the contaminating WBC are removed (with a 21% loss of platelets). This is believed to be because the interface between centrifuged platelets and WBCs is relatively large and cannot be clearly defined. In the ultimate separation of platelets from the original container, a relatively large interface and its poor confinement, in conjunction with the use of a flexible bag, will (1) obtain the maximum amount of platelets and (2) platelet product. Minimizing the WBC in the membrane makes fine separation difficult. In other words, with existing bag configurations, it is very difficult to obtain a clear boundary between the upper platelets and the lower WBCs (and remaining RBCs) that occupy the lower portion of a typical platelet collection bag. It becomes difficult. It would thus be highly advantageous to provide a separation system that allows simple and effective separation while providing a practical means of preserving the platelet/WBC interface. - A separation method and device have now been devised that avoid the above-mentioned problems. Unlike the relatively complex, expensive and totally interfacially disturbed separations used in the past, the method of the present invention is considerably simpler. The details are described below.

A method that ensures separation of WBC and platelets is that when the contents of the container (WBC, a mixture of remaining RBC and platelets) are separated (e.g. by centrifugation or other methods), a given volume of WBC and remaining Using a single flexible plastic bag having a series of interconnected receptacles suitable for receiving and confining RBCs at a visible and easily separable interface. It consists of things. In a preferred embodiment, the container used is a flexible bag having a sloped section adjacent to the receiver to aid in the transfer of a given component or subcomponent to the receiver during the separation process. In a further preferred embodiment, and during the M operation, at least a portion of the container is supported by a cup-like device. This inner surface matches at least a portion of the outer surface of the receptacle that is continuous with the +mM bag. Opportunity for platelet loss and interface disturbance f! A method to ensure separation of WBCs while reducing
e) Including the use of tools. In a preferred embodiment, the clip-spline combination is applied slowly and gently in a controlled manner at the interface to avoid disturbing the interface. An advantage to this method is that even if the clip-spline is inadvertently applied in the wrong location or inadvertently disturbs the interface, it can be easily removed. i.e. the seal is plastic),
3a can be used again (correctly) after recentrifugation.

The methods and devices of the present disclosure also ensure removal of residual RBCs from platelets. The exact location of the interface (WBC and RP
Adjustment of the position of the clip-on blister-in above or below the receiver is an important feature of the invention, as it varies depending on the volume of contaminant (C).

FIG. 1 shows one embodiment of a top view of a blood bag useful in the present method.

2 is a perspective view of the clip-spline device for the bag of FIG. 1; FIG.

Figure 3 shows WBC, one of the locations in area 3-3 of Figure 1.
Figure 2 shows a top view of the two clip-spline devices used to separate the bag from the platelets.

4 is a cross-sectional view of the clip-spline device of FIG. 2 at the location of FIG. 3 and taken along line 4--4 of FIG. 3;

EXAMPLE 1 Containers useful in the present disclosure are preferably flexible bags made of medical grade plastic material, such as polyvinyl chloride. Related patent application No. 585,793 cited as reference
detailed in the issue. The bag is fitted with a receptacle and the receptacle wall is continuous with the remaining walls of the bag.

Although such a container may be manufactured using conventional blood bag manufacturing techniques, in a preferred embodiment, the container itself (of a given large volume) and its A connected receiver (of smaller capacity), preferably a separation step and a WBC and a residual R[3C
The middle sloped (
It can be manufactured by simply end-sealing two opposing plastic sheets suitable to define the upper part of the receptacle connected by a section (at an angle of about 115-155°C to the interface). can. In the case of a platelet collection bag, the total volume of this bag is preferably approximately 450 n1, of which approximately 5-10 m1 constitutes a connection receptacle. This 5-1
0m1 receiver capacity is virtually all W13C/RB
To provide a bag in which C contaminants are collected and contained below an easily visible and separable interface, ie ensuring clean separation. Unlike prior art bags that have more than one compartment or chamber (e.g. U.S. Pat. Nos. 4,416,778 and 3,911,918), the connection between the receiver and the rest of the container is continuous. and fairly small boundary walls (i.e., the conduit does not isolate the receptacle;
Also, no valve means are required to open and close the receiver during centrifugation). As used herein, a continuous connection as applied to the bags of the present disclosure means that the receptacle wall is continuous with the remaining walls of the container and that the interior of the smaller receptacle (and its contents) ) is connected to the remaining or larger part of the bag at any time during the separation process. The successive receptacles are significantly smaller than the rest of the bag (approximately 1-2
% v/v) ensures a clear, separable, and visible interface between WBCs and platelets. Separation here means that the bag must be in such a shape that it can be easily sealed from the rest of the bag in a simple manner that does not disturb the contents of the receptacle or the platelet-WBC interface. do. Such decoupling is ensured by requiring that the volume of the receptacle is no more than about 1-2v/v% of the total bag volume and that the cross-sectional area of the receptacle is less than that on the remaining interface of the bag. . In use, the platelet collection bag containing both the platelets and unwanted WBCs and residual RPCs (if present) is centrifuged (e.g., 120 Orpm or 400 g for 10 minutes) and the WB
The C and RBCs are allowed to settle (migrate) into the receiver, where they create a distinct, divisible, visible and relatively small cross-sectional platelet/WBC interface. After such centrifugation and prior to transferring the platelets from the bag, clip-spline means of the present disclosure are placed over the interface (on the platelet side of the interface).
during platelet removal and/or management.
transfer from the receiver can be eliminated.

Variations of the bags of the present disclosure may be used with respect to conventional centrifuge equipment. However, the non-traditional bag shape does not match the centrifuge cups typically used to centrifuge the contents of blood bags. Such incompatibility would hinder the separation contemplated by the present disclosure by preventing the creation of a distinct and divisible platelet/WBC interface towards the top of the receptacle due to the flexible nature of the plastic bag. . The great flexibility of the bag allows centrifugal force or even just gravity to fold the receptacle part of the bag over the rest of the bag, at least the lower part of the bag whose inner surface is subjected to centrifugation if necessary. This can easily be avoided by fitting an insert into the centrifuge cup that best matches the outer surface of the centrifuge (including the receiver). Such an insert will remove at least the lower part (preferably all or most of the total bag) during centrifugation.
It should be made of any hard and durable material (eg, a structural foam such as polyurethane, polyolefin, polystyrene, etc.) that supports the. The outer surface of such a support does not matter as much as the inner surface, it is sufficient that the outer shape permits insertion into the centrifuge cup.

However, in an ideal situation, the outer portion of the support insert should mate flush with the inner surface of a conventional centrifuge cup, ensuring a snug and straight fit. Although the bags of the present disclosure are single-use, the inserts used to support the bags need not be.

The bottom of such an insert includes a slot through which a handle 6 (see Figures 1 and 3) extending from the receptacle may be pulled to properly position the bag prior to centrifugal sorting. Such inserts are manufactured by Miles Laboratories, Inc.
cutter group (cutte s, inc,)
rG roup ) to [Leukotrap Plateref 1--Pooling System (Leukotrap
P 1aLe-1eL Pooling System
) It is shown in the booklet published under the name J 1985. Various centrifuge cup inserts suitable for supporting bags before, during and after centrifugation are also shown in related patent application Ser. No. 585.793. Other insert shapes will occur to those skilled in the art in view of the above disclosure.

- see also the booklet mentioned above.

The separation methods of the present disclosure can be better understood from the drawings and detailed description and data below. FIG. 1 illustrates a blood bag, such as a platelet collection bag, useful with the principles of this disclosure. As can be seen, the bag 1 includes the usual outlet/inlet sections (any number of ports) and a backflow tube 4 for introducing or removing the contents of the bag. The upper part of the bag shown has substantially parallel sides, whereas the lower part of the bag l (
The right part) is inclined with an inclination angle 8 of approximately 135° and includes an imaginary interface area 9 as it approaches the receiver 7.

The interface area 9 between the receiver 7 and the remaining part of the bag (the upper (left) part 6 in FIG. 1 including the sloping portion) is the area between the dotted lines 9a and 9b in FIG. In use, it is preferred to keep this as small as possible to ensure fine separation. For platelet collection bags, approximately 5-1
A preferred interface separating the volume of the Company 0 receiver 7 and the upper contents volume of approximately 450 m1 is approximately 5 CI112. Because the interfacial area is visible and designed to be separable, the bag can be disassembled in a slow and deliberate manner that minimizes mixing of separated contents at the interface during transfer, removal, or management of the upper contents. It is suitable for receiving the clip-spline device of the present disclosure at approximately the location of interface 9.

FIG. 2 shows the clip 15 and spline insert 17 in perspective. Spline 17 is interfacial region 9a-9b
It is suitable for fixing the interface area of FIG. 1 in the clip 15 by snapping it over the entire length. In a typical embodiment, the clip 15 is made from a relatively hard polypropylene copolymer material and the spline 17 is made from a less stiff but firm and flexible polyvinyl chloride material. Other materials may be used as long as they permit the required clip-spline seal at interface 9 of bag 1. In a preferred embodiment, the splines can be deformed and the pvc bags and PV
The cold plastic flow of the C-spline is utilized to ensure a good seal near the top of the interface. Preferred dimensions for the clip-spline device (when used in the platelet bag described above) require that the spline 17 be longer than the clip 15. When using this simple spline-clip scissors device, the (interface 9) Spline 17
and the spline 17 is inserted into the clip 15 by pushing the bag l across the mouth 15a of the clip as shown in FIG.
Can be inserted into the middle. In one embodiment, the cylindrical P■C spline has a length of about 21/2 inches and a diameter of about 1/8 inch. This is at the interface 9,
Suitable for friction-tightly sealing the bag 1 into a clip having a length of about 2 inches and a horseshoe-shaped cross-section having a mouth 15a suitable for holding the bag 1 and splines 17 firmly and securely in place. ing.

FIG. 3 is a plan view of the clip-spline in place.

FIG. 4 is a side sectional view. Although the clip-spline combination described above is intended to be disposable, it may be reused if necessary or the protruding end of spline 17 may simply be pulled out and its position corrected. The spline 17 can be inserted into the clip 15 manually or, more preferably, this can be done using pliers-like tools specifically designed for this purpose. See brochure mentioned above. Such scissor jaws can be easily made given the geometrical factors in the clip-spline and interface.

In a typical embodiment, a platelet collection bag, such as that shown as 1 in FIG. 1, is made from a flexible plasticized material using conventional PVC bag production techniques.

The bag must be substantially transparent so that the interfacial area is visible. In a preferred embodiment, the bag is manufactured by U.S. Pat. No. 4,280,497.
- Consists of a plastic particularly suitable for the storage of platelets, such as plasticized pvC. The total capacity of the bag is approximately 450 + Ilj
! The capacity of the receiver is approximately 5 to 10 m1. The inclined section 5 has a volume of 70 m1 and the cross-sectional area of the interface 9 is approximately 5 CI112. The preferred support insert is made of polyurethane and supports approximately 80% of the outer surface of the total bag. Data demonstrating the effectiveness of the 6-line separation technique is provided in related patent application no.
No. 5,793.

Based on the concept of ``totanmema'', it seems that a person who is a ``masha'' will be able to recall many different meanings. Accordingly, the scope of the invention disclosed herein should be limited only by the claims.

[Brief explanation of the drawing]

FIG. 1 shows one embodiment of a plan view of a blood bag useful in the present method, FIG. 2 shows a perspective view of a clip varnish spline device relative to the bag of FIG. 1, and FIG. Location and WBC in area 3-3
4 shows a plan view of the clip-spline device on the bag used to separate the platelets from the platelets, and FIG. 4 shows the clip of FIG. 2 at the location of FIG. 3 and along line 4--4 of FIG. - a sectional view of the spline tool; Patent Applicant: Miles Laboratories Procedural Amendment Group Date: March 18, 1986

Claims (1)

[Scope of Claims] 1. (a) When dividing a mixture of platelets and leukocytes into platelet and leukocyte components, a device suitable for defining a given volume of leukocytes at an interface area that receives and is visible; introducing the mixture into a flexible container having receivers connected in series; (b) separating leukocytes from the mixture; and (c) establishing a seal between the contents of the receiver and the remainder of the bag. A method for reliably separating leukocytes from a mixture of leukocytes and platelets, comprising applying a clip-spline device to a visible interface under conditions sufficient to ensure at the visible interface area. 2. The clip-spline device comprises a generally long concave clip seat comprising a relatively hard plastic material at least as long as the visible interface, and clips the clip and spline at the visible interface area on the bag. 2. The method of claim 1, further comprising a relatively stiff plastic spline suitable for retention by frictionally fitting into the concave portion of the elongate clip when placed in mounting relationship. . 3. The method according to claim 1, wherein the part of the bag placed in front of the receiver is inclined. 4. The method of claim 1, wherein the container includes suitable means for supporting at least part of the outer surface of the container and receiver during separation. 5. The support portion contains a cup-like device, the inner surface of which matches the external dimensions of at least a portion of the receptacle, and the contents to be separated and for positioning the receptacle in the cup-like device. 5. A method according to claim 4, comprising a container comprising useful opening means at its bottom. 6. An internal cross-sectional area in which the receiver is in continuous communication with the container and is suitable for receiving leukocytes when the mixture in the container is subjected to centrifugal or sedimentation forces; Claims comprising means for reducing the interface between the leukocytes in the receiver and the platelets remaining in the container to be smaller than the inner cross-sectional area beyond the connecting region and towards the main part of the container. The method described in item 1. 7. Both the container and the receiver are made of flexible polymeric material;
2. A method as claimed in claim 1, in which the container portion preceding the receptacle is inclined towards the receptacle so as to form an angle of inclination with an imaginary line defining the entrance to the receptacle. 8. The method of claim 1, wherein the container is part of a multiple blood bag system comprising a blood donor bag connected to one or more auxiliary containers through conduit means. 9. The method of claim 7, wherein the angle is in the range of about 115 to 155 degrees. 10. The method of claim 1, wherein the container is a platelet storage bag and the clip-spline device is removable. 11. (a) A mixture comprising platelets, white blood cells and red blood cells in a flexible, substantially transparent plastic bag comprising a major portion of a given volume and a sub-portion of a given smaller volume. and the sub-section includes a receptacle whose interior is continuous with the interior of the main section;
This receiver is suitable for receiving both white blood cells and red blood cells when the mixture in the bag is centrifuged and for defining a visible interface at the junction between the platelets and the white blood cells and red blood cells in the receiver. and this interface has a cross-sectional area that is smaller than the cross-sectional area of any of said main parts of the bag and at least as large as the largest cross-sectional area of the receptacle; (b) and (c) centrifuging the bag under conditions sufficient to ensure that the bag is produced; and (c) subjecting the bag to visible A method for removing white blood cells and red blood cells from said mixture comprising the steps of: sealing at an interface. 12. The method of claim 11, wherein the seal uses a clip-spline forming a constricting seal of the bag at a visible interface.