Fluids, such as biological fluids are suspensions and can be separated into their constituent parts or fractions. For example, digested adipose tissue contains a stromal cell component and an adipocyte component that can be separated based upon the different densities of different cells and other particles in suspension in a device such as a centrifuge.
Devices for the separation of biological fluids into their constituent parts that utilize centrifugation have been described. For example, U.S. Pat. Nos. 7,390,484, 7,571,115, 7,585,670, and 7,687,059 describe exemplary devices that are useful for the processing of adipose tissue and separation and concentration of regenerative cell populations therefrom. U.S. Patent Application Publication No. 2008/0014181 describes an apparatus for separation of cells from a tissue sample. The device described in U.S. Patent Application Publication No. 2008/0014181 includes a centrifuge bowl, having an inner chamber with two lobes that protrude on opposite sides of the center of the bowl. In operation, centrifugal forces “pack” the cells into the lobes, while undesired fluid and components flow down the walls of the bowl to the center of the bowl via gravity. After removal of the undesired fluid components from the bottom of the bowl, fluid is jetted towards the lobes via spray nozzle located in the center of the centrifuge bowl, in order to dislodge and break up the cell pellets. The dislodged, broken up cells then flow to the bottom of the centrifuge bowl via gravity, where they are subsequently harvested.
Cell yield and viability, sterility, and processing time are parameters of utmost importance in the context of isolation of cellular components from biological tissues or fluids, e.g. for downstream use in either clinical or research settings. The need for devices designed to maximize cell viability, sterility, processing time, and ease-of operation while minimizing the device footprint is manifest.
The embodiments described herein relate to herein are improved centrifuge chambers and methods of using the same, which include features that advantageously improve upon sterility, processing time, cell viability, usability and footprint of other separation devices.
The embodiments disclosed herein relate to an improved centrifuge chamber, kits including a centrifuge chamber as described herein, and methods of separating desired particles from a suspension using a centrifuge chamber as described herein.
The container can be made of different types of materials. Preferably, the container is manufactured using medical grade materials. Preferably, the container is manufactured of a hydrophobic material, so that particles in the suspension do not stick to or adhere to the inner surfaces of the inner chamber.
As shown in
Each of the left 230 and right 240 sides of the bottom portion 200 is further defined by a center portion 291 that adjoins the left 230 and right sides 240, and distally located tapered pellet area ends 280, adjoining the center portions 291. Each center portion 291 is defined by a bottom surface and sidewalls 309. The bottom surface of each central portion is generally sloped at a first angle, θ1, that is less than 90° relative to the axis. The first angle Oladvantageously enables desired particles to travel up the sloped center portion and into the distal ends 281 of the container during centrifugation. Preferably, θ1 is between about 45° and 70°, relative to the axis 260, e.g., 45°, 46°, 47°, 48°, 49°, 50°, 51°, 52°, 53°, 54°, 55°, 56°, 57°, 58°, 59°, 60°, 61°, 62°, 63°, 64°, 65°, 66°, 67°, 68°, 69°, 70°, or any number in between. The sloped bottom surface 290 may have a curve, i.e., it may have a convex shape, or it may have a straight or substantially straight slope towards the center point 250. Regardless, the apex 292 of the sloped bottom surface 290 is distal to the center point 250, where the center portion 291 adjoins the respective tapered pellet area end portion 280. The nadir of the sloped bottom surface 290 is the center point 250. In some embodiments, the sidewalls 309 of the center portions 291 are vertical or substantially vertical (i.e., parallel or substantially parallel to the axis 260).
The tapered pellet area end portions 280 of the bottom portion 200 are each formed from sidewalls 309 and a bottom surface 290. The bottom surface 290 of the tapered pellet area ends 280 are also generally sloped at a second angle, θ2, that is greater than 90° relative to the axis 260. The second angle advantageously enables the retention of particles resuspended in the distal ends 481 following centrifugation, as discussed in further detail below. θ2 also advantageously allows for retention of resuspension fluid (e.g., fluid from the initial suspension, or the like) in the tapered pellet area portions 280 following centrifugation, while pelleted material remains packed/pelleted in the distal ends 481 of the tapered pellet area portions. θ2 also advantageously allows for transfer of resuspended material (e.g., resuspended particles such as cells), into the center portion 291 of the interior chamber, e.g. by implementing a vortex motion around the axis 260, as discussed in further detail below. Preferably, θ2 is between about 105° and 140°, relative to the axis 260. For example, θ2 can be 105°, 106°, 107°, 108°, 109°, 110°, 111°, 112°, 113°, 114°, 115°, 116°, 117°, 118°, 119°, 120°, 121°, 122°, 123°, 124°, 125°, 126°, 127°, 128°, 129°, 130°, 131°, 132°, 133°, 134° 135°, 136°, 137°, 138°, 139°, 140°, or any number in between. The apex 292 of the sloped bottom surface 290 of the tapered pellet area end 280 is proximal to the center point 250, and defines the location where the tapered pellet area end portion 280 adjoins the center portion 291. As can be seen in
The sidewalls 309 (e.g., of the central portions and the tapered pellet area end portions) have a top 310 and a bottom end 320, wherein the bottom end 320 of the sidewalls 309 adjoin the bottom surface 290 of the bottom portion 200, and wherein the top end 310 of the sidewalls 309 form a first mating surface 330. The first mating surface 330 formed by the top end 310 of the sidewalls has the same shape and has complementary angles and slopes to a second mating surface 340 defined by the sidewalls of the top portion 400, as discussed below. The top end 310 of the sidewalls of the center portion 291 can be perpendicular to the axis 260, while the top end 310 of the sidewalls of the tapered pellet area end portions 280 can be angled, e.g., sloped at the angle θ2 relative to the axis 260. The top portion 400 and bottom portion 200 of the container 110 can be fixably attached by coupling the first 330 and second 340 mating surfaces.
In some embodiments, the bottom portion 200 forms part of a locking means that secures the container into a cradle that forms part of a centrifuge. For example, in some embodiments, the exterior surface 202 of the bottom portion 200 can include two or more symmetrical legs 350, as depicted in
An exemplary cradle 800 useful in the embodiments disclosed herein is depicted in
The exemplary cradle 800 shown in
In some embodiments, the exterior surface 202 of the bottom portion 200 can include one or more symmetrical locking pins 370, e.g., as depicted in
An embodiment showing a locking mechanism that comprises a locking pin 370 coupled with a cradle 800 is depicted in
In some embodiments, the exterior surface 202 of the bottom portion 200 can include an indicator means, which functions to generate detectable signal when the centrifuge chamber is properly loaded and locked in a centrifuge chamber. In some embodiments, the indicator means can be one or more symmetrical ribs 390 located on the exterior surface 202 of the bottom portion 200. For example, when the centrifuge chamber 100 is positioned correctly and locked into the centrifuge cradle, the one or more symmetrical ribs 390 can push on an indicator pin 850 within the cradle, causing the pin to change position and actuate an inductive sensor, as discussed in further detail below. The change in position can be detected, e.g., by an electrical, optical, or other means, thereby indicating that the centrifuge chamber 100 is properly loaded and locked within the cradle.
Various views an exemplary top portion 400 of a container 110 as described herein are shown in
The sidewalls 450 of the top portion 400 have a top end 530 and a bottom end 540. The top end 530 adjoins the top surface 460 of the top portion 400, and the bottom end 540 forms the second mating surface 340 discussed above. The second mating surface 340 has the same shape as, and complementary angles to, the first mating surface 330 of the bottom portion 200. The first 330 and second mating surfaces 340 can be joined together using any art-accepted means (e.g., glue, screws, clips, nails, bonds, or the like, including combinations thereof), thereby forming the container 110.
In some embodiments, the top portion 400 can optionally include one or more vents 510, e.g., sterile vents, coaxial and symmetrically positioned around the axis 260, e.g., as depicted in
In some embodiments, the top portion 400 also optionally includes one or more ports 520 that allow sterile access into and out of the interior chamber 101, thereby providing for sterile ingress and egress of material into and out of the interior chamber 101. By way of example only, each of the left 410 and right 420 sides of the top portion 400 can include symmetrical ports 520. Exemplary ports 520 located in the tapered pellet area ends 440 of the right and left sides of the top portion 400 are shown in the top portion depicted
As discussed above, the bottom surface 290 and optionally the top surface 460, of the tapered pellet area ends 280/440, respectively, of the container 110 slope downwards and away from the axis 260, e.g., at the angle θ2. The angle of the tapered pellet area ends 280/440 of the interior chamber 110 advantageously enable the retention of unpelleted material within the tapered pellet area ends. Due to the slope of the tapered pellet area end, gravitational forces provide for the retention of a volume of unpelleted material within the tapered pellet area end portions of the interior chamber 101 following centrifugation. As explained in further detail below, the unpelleted material within the tapered pellet area end portions can advantageously be used to resuspend material pelleted in the distal ends, e.g., by rotating or shaking the chamber (vortexing mode) about the axis, as discussed in further detail below.
The contour of the distal ends of the tapered portions of the interior chamber can be substantially U-shaped or V-shaped, e.g., as shown in
The centrifuge chambers provided herein can also optionally include a fluid transfer assembly, configured to permit ingress and egress of material in and out of the interior chamber of the container. An exemplary fluid transfer assembly 600 is shown in
The fluid transfer assembly can include a ball bearing 660 that fits around the exterior surface of the outer straw 690 between the fluid transfer coupling 630 and the center point aperture 500 of the top surface 460 of the top portion 400 of the container. The ball bearing 660 is configured to allow for rotation of the container 110 around the fluid transfer assembly 600 and coaxial axis 260, while the outer and inner straws (610, 620), as well as the fluid transfer coupling 630 remain stationary. The exemplary ball bearing 660 depicted in
In some embodiments, the exterior surface 480 of the top portion 400 has radially symmetrical protrusions 481 around the center point aperture 500, e.g., as depicted in
Methods of Isolating Desired Particulates from Suspensions
Provided herein are methods of isolating desired particles from suspensions, using the centrifuge chamber described herein. For example, some embodiments provide for the isolation of a desired cell population from a cell suspension, e.g., the isolation of stromal vascular cells from disaggregated adipose tissue, stromal cells from bone marrow, and the like.
To separate desired particles from a suspension, a centrifuge that has a cradle with which the centrifuge chamber described elsewhere herein mates, and which also includes a driver that provides rotational force around the axis of the container, is provided. The centrifuge chamber can be inserted and locked into position in the cradle. For example, insertion and locking of the centrifuge chamber into the centrifuge can be accomplished by mating a patterned surface located on the exterior surface 202 of the bottom portion 200 of the container 110 (e.g., on at least two symmetrical legs 350 as described above), with a complementary patterned surface present on a cradle for the centrifuge chamber 100. In some embodiments, the patterned surface of the symmetrical legs 350 can function to strengthen the container 110. Alternatively, or in addition to, the patterned surface (e.g., on legs extending from the exterior surface of the bottom portion 200), the insertion and locking in position of the centrifuge chamber 100 into a cradle can include locking a pin 370, e.g., that extends from the center point 250 of the bottom portion 200, described above, into a complementary structure (e.g., such as a spring-loaded structure) in the cradle. As discussed above, in some embodiments the cradle of the centrifuge and the container 110 together provide an indicator means (e.g., by movement of a pin or the like in the cradle as described above). In such embodiments, the methods can include the step of receiving an indication that the container 110 is correctly positioned and locked within the cradle.
In some embodiments, the bottom portion 200 can optionally include flanges 361 that extend from each symmetrical leg 350 to the exterior surface of the tapered pellet area end 280, e.g., as depicted in
The suspension can be transferred into the interior chamber 101 of the container 110. In some embodiments, transfer of the suspension to the interior chamber 101 of the container can be achieved using one or both ports 520 in the tapered pellet area ends 440 of the top portion 400 of the container 110, if present. Alternatively, or in addition to, use of ports 520 in the tapered pellet area ends 440, material can be transferred to the interior chamber 101 of the container 110 via a fluid transfer assembly 600, e.g., via a outer straw port 650 that provides access to the interior portion of the outer straw 680 of a fluid transfer assembly 600 as described herein. As such, ports 520 located on the tapered pellet area ends 440 of the top portion, or a fluid transfer assembly 400 as described herein, can be used to introduce material (e.g., cell suspensions or the like), into the interior chamber 101 of the container 110.
Once the fluid suspension is transferred into the interior chamber 101 of the container, a separation step is then performed, by causing the container 110 to rotate around the axis 260 (e.g., via any art-accepted drive in the centrifuge). The rotation generates a centrifugal force within the chamber 110 causing particles to move radially outward from the center point 250 in a density-dependent manner. The speed at which the container is rotated about the axis 260 for separation of desired materials is readily apparent to the skilled person. By way of example only, stromal vascular cells can separated from undesired material by centrifugation at 1000g. Due to the sloped configuration of the bottom surface 290 of the center portion 291 of the interior chamber 101, particles (e.g., desired cell populations or the like) will be forced against and up the slope to the apex, and will then migrate downwards to the distal ends 281 of the tapered portions 280 of the chamber, where the particles (e.g., desired cell populations or the like) pellet. As discussed above, due to the downward and outward—facing slope of tapered pellet area ends, gravitational forces cause a portion of fluid to be retained within the tapered pellet area ends along with the pelleted material following centrifugation. The less dense portion of the suspension will substantially remain in the center portion 291 of the interior chamber 101. As such, the desired particles are separated from less-dense portions of the suspension. Thereby, the method provides for the separation of a population of cells from undesired components within a cell suspension.
In some embodiments, the methods include the step of removing the desired particles pelleted in the distal, tapered pellet area ends 281 of the container. In embodiments wherein the centrifuge chamber 100 includes ports 520 providing sterile access to the tapered pellet area ends 440280 of the top portion, a capture device (e.g., a syringe, or the like) connected to the port 520 can be used to introduce material into and/or remove material out of the tapered pellet area end of the interior chamber. Accordingly, some embodiments include the step of introducing a resuspension material into one or both of the tapered pellet area ends of the interior chamber, and resuspending pelleted material located in the distal ends 281 of the tapered portions with the resuspension material. In some embodiments, the pelleted material is merely resuspended in the residual fluid retained within the tapered portion 280/440 following centrifugation. In some embodiments, the removing step involves collecting resuspended material through one or both of the ports 520 located in the top portion 400 of the chamber 100.
In some embodiments, the methods include the step of resuspending material pelleted in the tapered pellet area ends, and transferring the resuspended material to the center extraction well 270 in the center of the bottom portion 200, where it is subsequently removed. In these embodiments, the methods include the step of removing undesired material in the suspension, e.g., undesired components that have been separated from the desired particles (e.g., desired cell populations, or the like), from the center portion 291 of the interior chamber 101, prior to transferring the resuspended material (comprising the desired particles) to the center portion 291of the interior chamber 101. Accordingly, some embodiments the methods provide a step of removing undesired components and/or material via an outer straw 610 in a fluid transfer apparatus 600 as described herein. Removal of undesired components through the outer straw port 650 connecting to the interior 680 of the cylindrically shaped outer straw of the fluid transfer system can be accomplished by virtue of applying a vacuum (manual or automatic) to draw fluid from the center extraction well 270 up into and through the interior of the outer straw, through the outer straw port 650 in the fluid transfer coupling 630.
Once undesired material is removed from the center portion 291 of the interior chamber 101, the pelleted material present in the tapered pellet area end portions 280/440 of the container 110 can be resuspended. As discussed above, resuspension of the pelleted material can be resuspended in fluid introduced into the tapered pellet area ends 280/440 through ports 520 located in the tapered pellet area ends 440 of the top portions 400 following centrifugation, or the pelleted material can be resuspended in residual fluid present in the tapered pellet area ends 280/440 following centrifugation. Regardless, resuspension of the pelleted material can be manual or automated. For example, in some embodiments, a syringe coupled to a port 520 in the tapered pellet area end of the top portion 400 can be used to manually resuspend pelleted material. Alternatively, material can be resuspended in an automated fashion via a syringe or other means coupled to a port in the tapered pellet area end 440 of the top portion 400. In yet other embodiments, the methods include the step of automatically resuspending material in the tapered pellet area ends by engaging the centrifuge chamber in a vortex mode, in which the centrifuge chamber is rotated and/or moved about the axis in such a way as to cause pelleted material to be dislodged and separated in resuspension fluid present in the tapered pellet area ends.
Resuspended material in the tapered pellet area ends 280/440 can be transferred to the center portion, i.e., to the center extraction well 270 in the bottom surface of the bottom portion 200 following resuspension. In some embodiments, transfer of the resuspended material involves engaging the centrifuge chamber 100 in a transfer mode, in which the centrifuge chamber 100 is rotated and/or moved about the axis 270 in such a way as to cause resuspended material to travel from the tapered pellet area ends down into the central portion of the container, where it settles in the center extraction well 270 of the bottom portion 200. For example, in some embodiments, the transfer mode involves causing the centrifuge chamber to decelerate rapidly, or alternatively abruptly. In some embodiments, the rapid deceleration is achieved via a braking system in the centrifuge.
Resuspended material located in the center extraction well 270 of the bottom portion 200 can be removed, in some embodiments, using the fluid transfer assembly 270. In some embodiments, a vacuum is used to pull the resuspended material up through the interior 670 of the cylindrically shaped inner straw, where it can be removed through the inner straw port 640.
Embodiments provided herein also relate to kits that include the centrifuge chambers discussed herein above. For example, some embodiments relate to a kit that consists of, or comprises, a container as described herein. The kits can also optionally include a fluid transfer assembly as described herein, one or more syringes configured to couple to a port of the centrifuge chamber, or both. Some kits optionally include conduits capable of being coupled e.g., in a manner to provide a sterile fluid pathway, to the inner straw and outer straw ports of a fluid transfer assembly, and/or to one or more ports located in the top portion of the container, thereby providing a sterile fluid pathway/closed system.
The above description and figures are illustrative of preferred embodiments which achieve the objects, features, and advantages of the present invention, and it is not intended that the present invention be limited thereto.
The present invention was made with government support under the following grants: HHSθ100201200008C awarded by the Department of Health and Human Services. The government has certain rights in the invention.
Filing Document | Filing Date | Country | Kind |
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PCT/US2015/039250 | 7/6/2015 | WO | 00 |
Number | Date | Country | |
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62022131 | Jul 2014 | US |