The present invention relates generally to the field of cell culture and, in particular, to a cell cultivating apparatus for the co-culture of multiple cell types in a single apparatus.
In vitro culturing of cells provides material necessary for research in pharmacology, physiology, and toxicology. Recent advances in pharmaceutical screening techniques allow pharmaceutical companies to rapidly screen vast libraries of compounds against therapeutic targets. These large-scale screening techniques require large numbers of cells grown and maintained in vitro. Growing and maintaining these large numbers of cells requires large numbers of cells as well as large volumes of cell growth media and reagents and large numbers and types of laboratory cell culture containers and laboratory equipment. This activity is expensive and labor intensive. Large-scale screening techniques provide market pressure for the development of new and improved cell culture techniques to provide more efficient and less expensive large-scale cell culture equipment.
In addition to the challenges of large-scale culture, particular cell types can represent special problems. For example, growing stem cells in culture can be quite difficult. A successful stem cell culture provides conditions that keep stem cells either dividing but not differentiating or differentiating into a defined cell type. It is desirable to be able to maintain stem cells in an undifferentiated state, and to control the transition of stem cells in culture from an undifferentiated to a differentiated state. These cells may not be robust in culture, and may require very specific cell culture conditions in order to thrive. Each of these conditions represent significant challenges for cell culture, especially large-scale cell culture.
Currently, many researchers find that successful conditions for stem cell growth require the presence of a layer of non-stem cells in the same culture environment as the stem cells. These non-stem cells are called “feeder cells” and are often grown as a first layer of cells in a stem cell culture. These feeder cells are often mouse cancer cells, but they may also be derived from human or other animal sources. The feeder layer provides a source of biologically active components that nourish the stem cells. They may also provide an extracellular environment for the stem cells that allows the stem cells to adhere to a surface in culture. The feeder cells may be irradiated to prevent them from growing. However, it is often difficult to separate stem cells from the feeder cells that are co-cultured in a single cell culture vessel. The process of purifying one cell type from the other is fallible, and the stem cell culture can become contaminated with feeder layer cells. It is desirable to provide devices and methods for growing multiple cell types together in culture, for example to allow feeder cells to share biologically active components with stem cells (“paracellular communication”), but yet allow for the cell types to be reliably separated from each other.
Feeder cells can be used to “condition” cell culture media. For example, feeder cells can be grown in media for a time, and that conditioned media can be harvested and used, processed or unprocessed, as growth media for stem cells. This step of conditioning cell culture media is time consuming and introduces added risk of contamination by introducing additional handling steps.
In addition, oxygen tension is a cell culture parameter that has been found to have a regulatory function in the differentiation of stem cells. For example, stem cells may grow in an undifferentiated state better in a relatively low oxygen environment, while feeder cells may prefer a relatively high oxygen environment. A vessel that permits better control of cell culture parameters such as oxygen content for co-cultured cells would also be beneficial.
In addition, cell-based high throughput applications have become automated. Automation permits manipulation of the cell culture vessel, such as roller bottles, cell culture dishes and plates, multiwell plates, microtiter plates, common flasks and multi-layered cell growth flasks and vessels, much like the manipulations performed by the manual operator. It is desirable to provide cell culture vessels which are amenable to automation systems that are currently available and to automation systems that are in development. Additionally, it is desirable that the cell culture apparatus will be suitable for use in the performance of high throughput assay applications that commonly employ robotic manipulation.
Further, flask vessels having multiple layers of cell growth are capable of producing a greater cell yield than commonly known flasks that permit growth of cells on a single bottom wall. There is a need for multi-layered cell culture flasks or vessels that provide for the co-culture of cells and the effective separation of co-cultured cells one from the other, while still providing adequate gas exchange.
In embodiments, the present invention provides a cell culture apparatus for the co-culture of at least two cell types. The cell culture apparatus has a plurality of cell culture chambers each having a top surface, a bottom surface and sidewalls. These cell culture chambers are structured and arranged to provide a container for growing cells in culture. In embodiments, at least two of the cell culture chambers share a common top surface and a bottom surface. This shared surface may be a microporous or track-etched membrane. One of the top surface and bottom surface may be a gas permeable, liquid impermeable surface. In embodiments, the cell culture apparatus may have at least one tracheal chamber in communication with the at least one gas permeable, liquid impermeable surface of at least one cell growth chamber. In embodiments, at least one of the top surfaces or bottom surfaces is rigid or deformable. In embodiments, the cell culture apparatus provides an integral multi-layer cell culture apparatus which allows air flow to the chambers by means of the tracheal chambers, and has cell culture chambers that can be used to co-culture cells, where the cells can share biologically active compounds through a gas permeable, liquid permeable membrane, but where the cells themselves are cultured in separate chambers. In embodiments of this apparatus, separate populations of cells can share media but remain pure uncontaminated cell types in culture. For example, embodiments of the present invention can be used to co-culture stem cells and feeder cells so that the two populations of cells can share biologically active compounds, but remain separate from each other in culture.
In further embodiments, the tracheal chamber can be filled with a porous material, or a filter or fibrous material. In additional embodiments, at least one of the top surface or bottom surface can be a liquid and gas-impermeable material.
In embodiments, the cell culture apparatus of the present invention may also have a port connected to a manifold to provide access to the interior spaces of the cell culture chambers. For example, two ports can be separated from each other in a manifold, and can be structured and arranged to provide separate access to the interior spaces of cell culture chambers containing separate cell types in culture. The manifold may also have liquid control devices such as valves to assist with the introduction and evacuation of cells and media into and out of cell culture chambers.
In embodiments, two cell growth chambers alternate with a tracheal chamber in successive orientation to create a multi-layer cell culture apparatus. For example, two cell growth chambers and a tracheal chamber may be considered a co-culture unit, and multiple co-culture units can be combined together to form an integral multi-layer co-culture apparatus.
In additional embodiments, the present invention provides a cell culture apparatus for the co-culture of at least two cell types structured and arranged so that adjacent cell culture chambers share a common top or bottom surface and that surface is a microporous or liquid permeable membrane, and so that one cell culture chamber has a gas permeable, liquid impermeable surface in adjacent to an air space or a tracheal space and the other cell culture chamber is not in communication with air through a gas permeable, liquid impermeable surface. In this embodiment, the multi-layer co-culture vessel provides co-culture units each having a high oxygen chamber and a low oxygen chamber.
Embodiments of the present invention also include a multi-layer cell culture vessel manifold having at least two apertures wherein the apertures provide separate access to at least two groups of cell culture chambers.
These, as well as other aspects and advantages of the present invention will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof in conjunction with the accompanying drawings.
The invention can be understood from the following detailed description when read with the accompanying figures. It is emphasized that the various features are not necessarily drawn to scale. In fact, the dimensions may be arbitrarily increased or decreased for clarity of discussion.
In embodiments, the present invention provides a multi-layer cell co-culture vessel which allows for the co-culturing of at least two different types of cells. The cell culture vessel allows for co-cultured cells to be in liquid contact with each other, to share biologically active molecules, without requiring that the different types of cells occupy the same cell culture chamber. In other words, in embodiments, the present invention allows for different cell types to share media without contaminating essentially pure populations of cells. In addition, embodiments of the present invention provide mechanisms to independently control some of the parameters of cell culture including exposure to oxygen. Embodiments also include mechanisms to allow for separate access to cell culture chambers containing different cell types, to prevent contamination of cells in culture as cells and media are introduced into and removed from the cell culture vessel.
In the following detailed description, for purposes of explanation and not limitation, exemplary embodiments disclosing specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one having ordinary skill in the art that the present invention may be practiced in other embodiments that depart from the specific details disclosed herein. In addition, specific features disclosed in exemplary embodiments may be combined in ways not specifically shown in the following figures. In other instances, detailed descriptions of well-known devices and methods may be omitted so as not to obscure the description of the present invention.
Turning now to the figures,
In an embodiment, the gas permeable liquid impermeable surfaces of the cell culture chambers can be any gas permeable liquid impermeable material. The material can be rigid or deformable. Gas permeable liquid impermeable surfaces may be made of one or more materials known in the art. The membrane allows for the free exchange of gases between the interior of the flask and the external environment and may take any size or shape, so long as the membrane is supportive of cellular growth. A preferred embodiment would include a membrane that is additionally durable for manufacture, handling, and manipulation of the apparatus.
Gas permeable liquid impermeable membranes typically are made of suitable materials that may include for example: polystyrene, polyethylene, polycarbonate, polyolefin, ethylene vinyl acetate, polypropylene, polysulfone, polyethylene terephthalate, polytetrafluoroethylene (PTFE) or compatible fluoropolymer, poly(styrene-butadiene-styrene) or combinations of these materials. As manufacturing and compatibility for the growth of cells permits, various polymeric materials may be utilized. For its known competency, then, polystyrene may be a preferred material for the membrane (of about 0.003 inches in thickness, though various thicknesses are also permissive of cell growth). As such, the membrane may be of any thickness, preferably between about 25 and 250 microns, but ideally between approximately 25 and 125 microns. 25.4 microns=0.001 inch.
Suitable gas permeable liquid impermeable membranes are available commercially and include POLYFLEX® (0.002 inch thick polystyrene film manufactured by Plastics Suppliers, Inc., Columbus, Ohio), BREATHE-EASY™ (non-porous polyurethane from Diversified Biotech, Boston, Mass.), SBS/EVA/SBA, a three-layered co-extruded film of styrene-butadiene-styrene/ethyl vinyl acetate/styrene/butadiene/styrene, non-porous film from BASF, Germany), SBS/PE, a two-layered co-extruded film of styrene-butadiene-styrene/polyethylene from Cypress Cryovac/Sealed Air Corp., Rochester, N.Y.), polyester (Perfec-seal Inc., Philadelphia, Pa.), TYVEK® 1073 (polyolefin microporous non-woven membrane from E.I. du Pont Wilmington, Del.), polyethylene (from 3M, Inc, Minneapolis, Minn.), POLYSEP® (microporous polypropylene sheet manufactured by Micron Separations, Westborough, Mass.), and microporous poly(tetra)fluoroethylene (PTFE) and HYRDULON® (microporous hydrophobized nylon 6,6, both manufactured by Pall Corporation, Port Washington, N.Y.).
When these materials are thinner, they are deformable. That is, at a thickness of approximately 0.001-0.005 inches, these materials can bend without breaking. These materials are not elastic, in that they cannot be stretched and then return to their original shape. However, they are deformable. They can bend. They can take on shapes defined by frames or containers or external supports that they are placed into. Thicker layers of these materials are generally more rigid. For example, polystyrene at a thickness of 0.01 is a deformable material. The same material at a thickness of greater than approximately 0.015 is a rigid material. The gas permeability of these materials is also related to the thickness of the material. Thicker materials are less gas permeable.
Suitable material for gas permeable liquid permeable membranes, or microporous membranes include but are not limited to polymeric material such as polyethylene terephthalate, polycarbonate and the like with open pores extending through the membrane. The membrane may be about 8-120 micrometers thick and pores may be between about 0.01 micrometers to about 10 microns in diameter with a pore density between about 1.0×105 to about 1.0×109 pores per square centimeter. Microporous membranes include track-etched membranes sold as “CYCLOPORE™” (Avenue Einstein, Louvain-la Neuve, Belgium) and “PORETICS™ (Livermore, Calif.). The gas permeable liquid permeable microporous membrane allows fluid communication between the cell culture chambers in the co-culture apparatus, but does not allow physical contact or migration of cells from one cell culture chamber to another.
The optimal pore size of gas permeable liquid permeable materials, or microporous materials, may vary depending upon the cell culture conditions, the cells in culture, and the purpose of the cell culture. For example, if a chemotactic compound is added to the media of one cell culture chamber separated by a microporous membrane from a second cell culture chamber, the pore size necessary to keep the cell types separated may be significantly smaller than the pore sizes necessary to separate cells that are not induced to migrate. Similarly, if the induction of migration is a goal of cell culture, microporous membranes having larger pore sizes may be advantageous. For example, if it is desired to mix cells in co culture, a chemotactic agent can be added to one cell culture chamber to induce the cells in the adjacent cell culture chamber to migrate through the microporous membrane. The timing and conditions of such cell mixing may be controllable by changing the media in one or both cell cultures.
Although not shown in
Cells can be grown in the cell culture chambers 1 shown in
Distinct cell types can be cultured in cell culture chambers 1. That is, in an embodiment of the present invention, one cell type can be cultured in one cell culture chamber, and another cell type can be cultured in a second cell culture chamber. Because gas exchange is achieved via the gas permeable membranes, it is not necessary to leave an air gap within the cell culture chambers, and it is possible to completely fill the cell culture chambers with cells and media. However, it may be desirable to provide an air gap.
Where the cell culture chambers are separated by a liquid permeable membrane, the two cell types can communicate bioactive compounds to each other through the membrane, while the distinct populations of cells remain separate from each other. In this way, cell culture media can be “conditioned” by one cell type which contributes bioactive compounds to the media, so that a second cell type can grow in the conditioned media, without contaminating the populations of cells in culture, and without the added steps of separately culturing the “feeder” cells in culture, harvesting the supernatant from those cells, and providing that conditioned media to a second cell type.
Also shown in
The gas permeable membrane may also serve as a growth surface for cells. While others have disclosed the use of elastic materials, specifically elastic materials which can stretch to be at least 100 times the starting volume (U.S. Pat. No. 6,468,792) as a support surface for cells in culture, elastic surfaces are not preferable for cell culture, especially with regard to cells which adhere to a surface in culture. When cells that adhere to a surface are grown in culture, and the surface is elastic and stretches, this stretching of the cell culture surface may dislodge the cells from the substrate and disrupt the cell culture.
As shown in
Below the tracheal chamber 15, cell culture chamber 18 will also be a well-oxygenated cell culture chamber because its top most surface is a gas permeable membrane adjacent to a tracheal chamber 15. Cell culture chamber 19 is bounded on its top most surface by a GPLP membrane and is in liquid communication with cell culture chamber 18. Cell culture chamber 19 is bounded on its bottom surface by a GILI membrane 7. Cell culture chamber 19 will experience reduced oxygen tension because it is not in communication with an air pocket or tracheal chamber. Oxygen will diffuse into cell culture chamber 19 through cell culture chamber 18, which is separated from a tracheal air chamber by a gas permeable membrane 9. The concentration of oxygen in any of these cell culture chambers can be described by Fick's law, and is a function of the depth of the media, or the distance from the gas layer to the cells in culture. In cell culture chamber 18, for example, the top of the cell culture chamber is in contact with a gas layer (the tracheal chamber), through the gas permeable membrane. Cells growing in culture chamber 19, however, are further from the gas layer. Therefore, cells growing in culture chamber 19, will experience less oxygen than cells growing in culture chamber 18.
Co-culture units 22 can be in many different configurations, depending upon the conditions that best meet the needs of the cells in culture.
In the embodiments represented in
While the cell culture chambers shown in
As can be seen from
Disposed within the flask 100 are individual cell growth chambers 1. The embodiment illustrated in
For example, shown in
Cell growth chamber 16 is bounded on its top surface by a gas impermeable layer and on its bottom surface by a gas and liquid permeable layer. Cell growth chamber 16 is in liquid communication with cell growth chamber 17, through the liquid and gas permeable membrane 5 between growth chamber 16 and growth chamber 17, allowing biologically active compounds to flow from growth chamber 17 to growth chamber 16, and from growth chamber 16 to growth chamber 17. In this configuration, cell growth chamber 16 is appropriate for growing cells which prefer low oxygen content, and which require the support of biologically active compounds released from a second type of cell, such as stem cells. Cell culture chamber 17 with its access to oxygen via the tracheal chamber, is appropriate for growing cells which require relatively higher oxygen content, and which supply biologically active compounds to a second type of cells, such as feeder cells.
Also shown in
As shown in
Likewise, high oxygen content cell culture chambers which might house feeder cells, such as cell culture chamber 18, may connect together in serial into opening 125 to allow unitary access to all of the high oxygen content cell culture chambers. Said another way, all of the stem cell culture chambers can be accessed together through a single aperture or opening, separate from the feeder cell chambers and feeder cell chamber opening. Or, the cell culture chambers of the present invention may be structured and arranged to all have equivalent access to oxygen, thereby providing equivalent growth chambers. In this case, cell culture chambers containing like cells can be accessed together through one aperture while cell culture chambers containing a second type of cells can be accessed together through another aperture.
Although two apertures on one end wall are illustrated in
Although not shown in
The apparatus of the present invention may be made by any number of acceptable manufacturing methods well known to those of skill in the art. In a preferred method, the apparatus is assembled from a collection of separately injection molded or extruded parts. Though any polymer suitable for molding and commonly utilized in the manufacture of laboratory ware may be used, polystyrene is preferred.
The gas permeable membranes 9 and 5 may be properly affixed to the supports 119 by any number of methods including but not limited to adhesive or solvent bonding, heat sealing or welding, compression, ultrasonic welding, laser welding and/or any other method commonly used for generating seals between parts. Laser welding around the circumference of the membranes 9 and 5 is preferred to establish a hermetic seal around the membrane region such that the membrane is flush with and fused to the face of the supports 119 and becomes an integral portion of the interior surface of the apparatus. Once the gas permeable membranes 9 and 5 are adhered, then layers of gas and liquid impermeable material may be joined, including the top plate 110 and bottom tray 120. The parts are held together and are adhesive bonded along the seam, ultrasonically welded, or laser welded. Preferably, laser welding equipment is utilized in a partially or fully automated assembly system. The top plate and bottom tray are properly aligned while a laser weld is made along the outer periphery of the joint. Advantageously and in order to enhance cell attachment and growth, the surfaces internal to the apparatus 100 may be treated to enable cell growth. Treatment may be accomplished by any number of methods known in the art which include plasma discharge, corona discharge, gas plasma discharge, ion bombardment, ionizing radiation, and high intensity UV light. Finally, a manifold 104 is aligned and fitted onto the port-end of the apparatus 100 and adhered to the apparatus.
In use, the apparatus 100 of the current invention is employed according to accepted and well known cell growth methods. Cells are introduced to the apparatus 100 though the aperture via the necked opening. Media is introduced such that the cells are immersed in the media. The apparatus is arranged such that the cell containing media fill the cell growth chambers. Advantageously, the apparatus 100 is capable of being completely filled with media since the gas permeable membranes 9 in combination with the tracheal spaces 15 provide uniform gas distribution to the cell growth chambers. This will further ensure the flow and exchange of gases between flask interior and the external environment. The apparatus is then placed within an incubator and may be stacked together with similar vessels such that a number of cell cultures are simultaneously grown. The apparatus is situated such that the bottom tray 120 assumes a horizontal position (or vertical position depending on the cell culture application). Another advantage of the apparatus 100 of the present invention is its enhanced capacity to grow cells on an opposing surface when the apparatus is rotated 180°.
The embodiments of the present invention may be modified to take the shape of any device, container, apparatus, vessel, or flask currently used in industry. Specifically, cylindrical or alternative vessels may utilize gas permeable substrates (internal to the vessel) in combination with tracheal chambers or spaces to provide an improved culturing environment for the growth of cells. A spiral or alternative approach inclusive of a tracheal chamber would therefore be possible.
In one embodiment, the present invention has a footprint conforming to industry standard for microplates (5.030+/−0.010 inches by 3.365+/−0.010 inches). For this reason, the neck portion is preferably recessed within the overall rectangular footprint. The advantage of providing an apparatus with such a footprint is that automated equipment designed specifically for the manipulation of microplates may be utilized with this apparatus with very little customized modification. Similarly the height, or the distance between the outer most portion of the bottom tray and the outer portion of the top plate, is approximately 0.685+/−0.010 inches. At any rate, the present invention is not intended to be limited in any way by the aforementioned preferred dimensions and in fact may be constructed to any dimension.
As presented, the multiple embodiments of the present invention offer several improvements over standard vessels currently used in industry. The improved co-culture device enhances the volume of cells that are capable of being cultured in the volume enclosed by traditional cell culture vessels. In addition, embodiments of the present invention allow for the construction of cell culture chambers for co-culturing different cell types that have different cell culture characteristics, including different exposures to oxygen. Successive layering of individual growth chambers and tracheal chambers inclusive of the gas permeable membranes makes oxygen and other gases from the external environment selectively available to the internal contents of the apparatus. Specifically, gaseous exchange with the nutrient media is conducive to an even distribution of cell growth when gas permeable membranes are utilized on at least one potential growth surface. The cell growth apparatus is capable of fully utilizing its capacity by allowing cells access to optimal volumes of nutrient media and direct oxygenation via the tracheal spaces. Additional benefits are afforded to the cell culturing apparatus in which the exterior framework is rigidly constructed, conveniently offering easy handling, storage, and accessibility.
A multilayered cell culture apparatus for the co-culturing of at least two cell types is disclosed. The cell co-culture apparatus is an integral structure having a plurality of cell culture chambers in combination with tracheal space(s). The body of the apparatus has imparted therein gas permeable membranes in combination with tracheal spaces that will allow the free flow of gases between some cell culture chambers and the external environment. In addition, some cell culture chambers may have limited access to air creating relatively lower oxygen content cell culture chambers. The size of the apparatus, and location of an optional neck section, allows for its manipulation by standard automated assay equipment, further making the apparatus amenable to high throughput applications.
As exemplified, the apparatus may include any unitary structure, vessel, device or flask with the capacity to integrally incorporate substrates in successive orientation. The invention being thus described, it would be obvious that the same may be varied in many ways by one of ordinary skill in the art having had the benefit of the present disclosure. Such variations are not regarded as a departure from the spirit and scope of the invention, and such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims and their legal equivalents.
The foregoing description of the specific embodiments reveals the general nature of the invention that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation and without departing from the general concept of the present invention. Such adaptations and modifications, therefore, are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance presented herein, in combination with the knowledge of one of ordinary skill in the art.
This application is a continuation of and claims the benefit of priority to U.S. application Ser. No. 11/807,442 filed on May 29, 2007, the content of which is relied upon and incorporated herein by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
4225671 | Puchinger et al. | Sep 1980 | A |
4296205 | Verma | Oct 1981 | A |
4661455 | Hubbard | Apr 1987 | A |
4734373 | Bartal | Mar 1988 | A |
4748124 | Vogler | May 1988 | A |
4770854 | Lyman | Sep 1988 | A |
4839292 | Cremonese | Jun 1989 | A |
4938196 | Hoshi et al. | Jul 1990 | A |
4945203 | Soodak et al. | Jul 1990 | A |
5026650 | Schwarz et al. | Jun 1991 | A |
5047347 | Cline | Sep 1991 | A |
5079168 | Amiot | Jan 1992 | A |
5139946 | Howell et al. | Aug 1992 | A |
5149649 | Miyanori et al. | Sep 1992 | A |
5153131 | Wolf et al. | Oct 1992 | A |
5190878 | Wilhelm | Mar 1993 | A |
5240854 | Berry et al. | Aug 1993 | A |
5310676 | Johansson et al. | May 1994 | A |
5330908 | Spaulding | Jul 1994 | A |
5416022 | Amiot | May 1995 | A |
5437998 | Schwarz et al. | Aug 1995 | A |
5476573 | Hirose et al. | Dec 1995 | A |
5523236 | Nuzzo | Jun 1996 | A |
5527705 | Mussi et al. | Jun 1996 | A |
5565353 | Klebe et al. | Oct 1996 | A |
5589112 | Spaulding | Dec 1996 | A |
5597731 | Young et al. | Jan 1997 | A |
5602028 | Minchinton | Feb 1997 | A |
5627070 | Gruenberg | May 1997 | A |
5658797 | Bader | Aug 1997 | A |
5686301 | Falkenberg et al. | Nov 1997 | A |
5686304 | Codner | Nov 1997 | A |
5693537 | Wilson et al. | Dec 1997 | A |
5702941 | Schwarz | Dec 1997 | A |
5714384 | Wilson et al. | Feb 1998 | A |
5763261 | Gruenberg | Jun 1998 | A |
5763275 | Nagels et al. | Jun 1998 | A |
5763279 | Schwarz et al. | Jun 1998 | A |
5783440 | Stevens | Jul 1998 | A |
5786215 | Brown et al. | Jul 1998 | A |
5801054 | Kiel et al. | Sep 1998 | A |
5912177 | Turner et al. | Jun 1999 | A |
5924583 | Stevens et al. | Jul 1999 | A |
6107085 | Boughlin et al. | Aug 2000 | A |
6114165 | Cai et al. | Sep 2000 | A |
6190913 | Singh | Feb 2001 | B1 |
6228607 | Kersten et al. | May 2001 | B1 |
6297046 | Smith et al. | Oct 2001 | B1 |
6410309 | Barbera-Guillem et al. | Jun 2002 | B1 |
6455310 | Barbera-Guillem | Sep 2002 | B1 |
6465243 | Okada et al. | Oct 2002 | B2 |
6468792 | Bader | Oct 2002 | B1 |
6518035 | Ashby et al. | Feb 2003 | B1 |
6548263 | Kapur et al. | Apr 2003 | B1 |
6555365 | Barbera-Guillem et al. | Apr 2003 | B2 |
6569675 | Wall et al. | May 2003 | B2 |
6576458 | Sarem et al. | Jun 2003 | B1 |
6588586 | Abasolo et al. | Jul 2003 | B2 |
6593136 | Geiss | Jul 2003 | B1 |
6653124 | Freeman | Nov 2003 | B1 |
6673595 | Barbera-Guillem | Jan 2004 | B2 |
6759245 | Toner et al. | Jun 2004 | B1 |
6794184 | Mohr et al. | Sep 2004 | B1 |
6811752 | Barbera-Guillem | Nov 2004 | B2 |
6821772 | Barbera-Guillem et al. | Nov 2004 | B2 |
6841384 | Robbins, Jr. | Jan 2005 | B2 |
6844187 | Wechsler et al. | Jan 2005 | B1 |
6855542 | DiMilla et al. | Feb 2005 | B2 |
6908767 | Bader | Jun 2005 | B2 |
7022518 | Feye | Apr 2006 | B1 |
7078228 | Lacey et al. | Jul 2006 | B2 |
7160687 | Kapur et al. | Jan 2007 | B1 |
7192769 | Pykett et al. | Mar 2007 | B2 |
7195758 | Schultze et al. | Mar 2007 | B2 |
20020039785 | Schroeder et al. | Apr 2002 | A1 |
20020110905 | Barbera-Guillem et al. | Aug 2002 | A1 |
20030008388 | Barbera-Guillem et al. | Jan 2003 | A1 |
20030008389 | Carll | Jan 2003 | A1 |
20030040104 | Barbera-Guillem | Feb 2003 | A1 |
20030143727 | Chang | Jul 2003 | A1 |
20040029266 | Barbera-Guillem | Feb 2004 | A1 |
20040043481 | Wilson | Mar 2004 | A1 |
20040132175 | Vertillard et al. | Jul 2004 | A1 |
20050009179 | Gemmiti et al. | Jan 2005 | A1 |
20050032208 | Oh et al. | Feb 2005 | A1 |
20050077225 | Usher et al. | Apr 2005 | A1 |
20050101009 | Wilson et al. | May 2005 | A1 |
20050106717 | Wilson et al. | May 2005 | A1 |
20050169962 | Bhatia et al. | Aug 2005 | A1 |
20050260745 | Domansky et al. | Nov 2005 | A1 |
20060003436 | DiMilla et al. | Jan 2006 | A1 |
20060019361 | Ng et al. | Jan 2006 | A1 |
20060031955 | West et al. | Feb 2006 | A1 |
20060112438 | West et al. | May 2006 | A1 |
20060121606 | Ito et al. | Jun 2006 | A1 |
20060136182 | Vacanti et al. | Jun 2006 | A1 |
20060141617 | Desai et al. | Jun 2006 | A1 |
20060252150 | Cheng | Nov 2006 | A1 |
20070026516 | Martin et al. | Feb 2007 | A1 |
20090100873 | Allan et al. | Apr 2009 | A1 |
20090250497 | Cox et al. | Oct 2009 | A1 |
20100043495 | Kirby et al. | Feb 2010 | A1 |
20100126226 | Zhou et al. | May 2010 | A1 |
Number | Date | Country |
---|---|---|
19844708 | Mar 2000 | DE |
0112155 | Dec 1983 | EP |
0155237 | Mar 1985 | EP |
0725134 | Aug 1996 | EP |
0890636 | Jan 1999 | EP |
1539263 | Jan 1979 | GB |
1990005179 | May 1990 | WO |
1991015570 | Oct 1991 | WO |
2001092462 | Dec 2001 | WO |
2003085080 | Oct 2003 | WO |
2004106484 | Dec 2004 | WO |
Entry |
---|
E. Metzen, M. Wolff, J. Fandrey, and W. Jelkmann, Pericellular PO2 and O2 consumption in monolayer cell cultures, Respiration Physiology 100 (1995) 101-106. |
Kamel Mamchaoui and Georges Saumon, A method for measuring the oxygen consumption of intact cell monolayers, American Journal of Physiology Lung Cellular and Molecular Physiology (2000) 278: L858-L863. |
Derwent Abstract for EP155236. |
E. Barbera-Guillem, “Overcoming cell culture barriers to meet the demands of cell biology and biotechnology”, Reprinted from American Biotechnology Laboratory, May 2001. |
“Cell Culture Equipment (Hardware & Devices)”, Lab Times, Products, Jan. 2006, pp. 52-58. |
International Search Report and Written Opinion PCT/US2008/006693 Dated Oct. 16, 2008. |
Number | Date | Country | |
---|---|---|---|
20160186113 A1 | Jun 2016 | US |
Number | Date | Country | |
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Parent | 11807442 | May 2007 | US |
Child | 15063040 | US |