The invention relates to a system and method for the separation and preparation of cells and/or tissue for microscopic examination. In particular, the invention relates to cell block preparation for immunocytochemistry studies of fine needle aspirates.
Fine needle aspiration (FNA) is a widely used screening diagnostic procedure. However, only a small and finite amount of material can be obtained by FNA. The current process in the clinical laboratory does not maximally use this limited amount of material. As a result, there is typically only enough material obtained to perform initial or screening tests. The limited amount of material collected through this procedure largely inhibits further classification of the disease, which results in more invasive procedures for a more conclusive diagnosis. This not only results in increased costs, but significantly delays the diagnosis as well.
The need remains for systems and methods which maximize the use of this limited material for different immunocytochemistry (ICC) studies to permit a more conclusive diagnosis to be made by a single FNA procedure alone and without the need for more invasive procedures.
An object of the invention is to provide a cytoblock preparation system that provides the necessary instrumentation to process a FNA for microscopic examination in a single piece of laboratory equipment. The system permits the preparation of multiple sections from a single FNA. Each section contains sufficient cells or material for staining or other studies. In one embodiment, the system provides a centrifuge, a vacuum device, a temperature incubation chamber, and a mixing device.
Another object of the invention is to provide a kit for use with the system which supplies the components required for processing of the specimen. In one embodiment, the kit provides a centrifuge tube containing a fixative, a matrix container containing a matrix material, a transfer tube with a tamping device, a tissue cassette, an embedding tray with a divider, and paraffin or other embedding material.
Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures.
The instrument 10 is designed for use with additional materials, including disposable and/or consumable components, required for processing of the specimen, which are desirably supplied in the form of a kit 20, as
The instrument 10 and associated kit 20 are particularly well-suited for use in preparing and processing specimens for immunocytochemistry (ICC) studies on the limited materials collected by FNA, biopsy, endoscopic procedures, washings, and lavages and therefore will be described in accordance with such use. It will be readily apparent, however, that the instrument 10 and kit 20 are also suitable for use in other studies, e.g., special stains, in situ hybridization, RNA and DNA studies, as well as in basic research requiring the collection and saving of treated cells.
Together, the instrument 10 and kit 20 provide a system that permits the preparation of multiple sections from a single FNA. Each section contains sufficient cells or material for staining or other studies.
In use, as shown in
It should be noted that it is also contemplated that the cellular material C could be added to a centrifuge tube 22 which does not already contain a predetermined quantity of fixative. In such an embodiment, an appropriate quantity of fixative would be added to the centrifuge tube 22 along with the cellular material C.
The tube 22 is then placed into the centrifuge 12 for separation. In a representative embodiment, the centrifuge 12 is a conventional low speed centrifuge 12 that permits the separation of the aspirate/fixative mixture into a supernatant S and a cell pellet P, as seen in
The supernatant S is then removed, as shown in
The matrix container 24 (which contains a viscous matrix mixture M is desirably pre-heated by placing the container 24 in the temperature incubation chamber 16. A variety of matrixes are available in the art, which include agar, agarose gel or “histogel” solid at ambient temperature, Methocell®, Matrix Gel®, OCT compounds, paraffin, denatured and non-denatured collagen, fibronectin, laminin, and mixtures thereof. Those skilled in the art will know of other suitable matrixes for cell immobilization, or will be able to ascertain such, without undue experimentation. The incubation chamber 16 may be a single chamber selectively adjustable over a broad range of temperature, e.g., between −50-100° C. Alternatively, the chamber 16 may include distinct heating and cooling chambers (e.g., a separate heating block and cold plate) that are independently adjustable within a defined temperature range, e.g., 50-100° C. and 2-8° C. respectively.
The matrix material M is pre-heated by selecting a temperature that permits liquefaction of the matrix. The incubation chamber 16 includes a well (not shown) or otherwise receives the matrix container 24 to heat the matrix material M to the desired temperature prior to adding the matrix material M to the cell pellet P. It will be readily apparent that the chamber may include a series of wells, which may be of the same or of different size and/or configuration, to accommodate multiple specimens and/or containers 24 of varying size or shape. In one embodiment, the temperature of the chamber 16 is first set to between 90-100° C. to liquefy the matrix material M. Once the matrix material M has been liquefied, the temperature is adjusted and lowered to 50° C. to maintain the matrix material M in the liquid state.
The pellet P is then removed from the centrifuge tube 22 by use of transfer tube 26 and tamp 28. The transfer tube 26 is a tube having a hollow core 42 and open end 44. The transfer tube 26 is placed into the centrifuge tube 22 and passed over the pellet P to retain the pellet within the hollow core 42, as shown in
The tube 26 and tamp 28 may be reusable, e.g., formed of metal, or may be suitable for disposal after a single use, e.g., formed of plastic. Additional embodiments of the transfer tube 26 and tamp 28 are shown in
b is similar to the embodiment of
c is similar to the preferred embodiment, however a spring mechanism is engaged between the transfer tube 326 and the tamp 328. In this embodiment, the tamp 328 is advanced by pushing on the tamp 328 to engage the spring. The tamp 328 is retracted from the tube 326 by again pushing on the tamp 328 to disengage the spring. This mechanism is similar to that utilized in a spring-retractable ball point pen. While the preferred embodiment discloses utilizing the transfer tube 26,126,226,326 and tamp 28,128,228,328 to transfer the cell specimen, it is also contemplated that the tube 26,126,226,326 and tamp 28,128,228,328 could have additional uses in the medical field, such as for taking dermatological biopsies.
The pellet P is then thoroughly resuspended and mixed within the matrix material M using the mixing device 18. In the illustrated embodiment, the mixing device 18 provides a mixing probe 48, which can be positioned within and near the bottom of the tube 24 and activated to provide mechanical stirring or mixing motion. It will be readily apparent that a variety of other mixing means may be provided, e.g., a vortex.
With reference now to
The matrix tube 24 desirably provides a tapered region 50 and reduced diameter chamber 52 similar to centrifuge tube 22. Chamber 52 serves to form and maintain the gelled specimen G in a desired shape or configuration. In a preferred embodiment, the chamber 52 is of a round or cylindrical configuration and results in the formation of an essentially round or circular gelled specimen G. It is to be understood that the chamber 52 may be variously configured to provide a gelled specimen G of a desired size and shape, e.g., square or oval.
After solidification, as shown in
In processing the specimen G by embedding, the specimen G is then placed into the tissue cassette 30. The cassette 30 may be formed of plastic or other any other suitable material, and may be adapted for multiple or single use. As shown in
The removable basket 56 preferably has at least one cylindrical chamber 54 integrally formed therein. However, it will also be readily apparent that the size, number, and configuration of the chambers 54 of the basket 56 may be varied to accommodate the procedures being performed and the number and types of specimens being processed. The removable basket 56 could be made of any suitable material, including, but not limited to plastic or foam.
After processing, the specimen G is transferred from the cassette 30 into a pre-bored hole or well 58 within the embedding block 34, as
In an alternative embodiment, block 34 may be provided in kit 20 without pre-bored wells 58. In this arrangement, transfer tube 26 is preferably formed of metal or otherwise adapted to bore through the block 34 to form a well 58 or series of wells 58 so that the number and placement of wells 58 may be determined by user.
The embedding tray 32, which is desirably complementary in size and shape to block 34, is placed over the block (
The tray 32, containing block 34 with specimen G, is then inverted and placed on the warming plate 60 (
In an alternative embodiment, wells 58 may be closed and the specimen G firmly embedded by pipetting or otherwise delivering heated, liquefied paraffin without use of the tray 32 (not shown). The paraffin may be pre-heated and liquefied by placing on warming plate 60, microwaving, or other suitable means.
In an additional alternative embodiment, the tray 32 may be provided with a partitioned insert 62 which includes multiple divisions 64, as shown in
The tray insert 62 may have any suitable number and configuration of divisions 64. The tray insert 62 may be made of any suitable material, including, but not limited to plastic or metal. This configuration would be particularly useful in creating a cell array containing cell samples from multiple origins, as is further described below.
The block 34 can then be placed on the cooling plate 19 or otherwise cooled to solidify the block 34 (
While the preferred embodiment of the invention utilizes cells obtained by fine needle aspiration, it should be clear to one of skill in the art that cellular material captured by other means could also be utilized to create a cytoblock. Cell material could also be collected by endoscopy, including but not limited to arthroscopy, bronchoscopy, colonoscopy, colposcopy, cystoscopy, ERCP (endoscopic retrograde cholangiopancreatograthy), EGD (esophogealgastroduodensoscopy), endoscopic biopsy, gastroscopy, laparoscopy, laryngoscopy, proctoscopy and thoracoscopy. Cells could also be obtained from lavage procedures, including but not limited to bronchoalveolar, breast ductal, nasal, pleural, peritoneal, gastrointestinal, arthroscopic, and urinary bladder lavages. It is also contemplated that cells could be collected from catheters such as those used in infusion, cardiovascular, rental, bladder, urothral, hemodynamic monitoring, neurological, and other procedures which would be obvious to one of skill in the art.
It is difficult to screen the expression level of a gene or molecule in different cell lines, especially for newly described ones. The current routine methods for this purpose include western blot, immunocytochemical study using fluorescence-labeled antibodies, real-time RT-PCR, northern blot, in-situ hybridization, etc.
The current sources of cells for research include commercial or privately-maintained sources of viable cells in culture, frozen viable cells of specific cell lines, and primary cultured cells derived from different organs/tissues from different organisms, plants, animals and/or human. It is very difficult and expensive to maintain these cells for scientists and researchers. A “Fixed or Permanent Cell Bank” may be provided to improve the current system and forms of cell sources. In this system, all cells from different possible sources (commercial companies, primary cultured cells derived from animals or other sources, etc.) are cultured, collected, fixed with a fixative (formalin, alcohol, et. al) and embedded in paraffin or other materials to form a long-lasting (permanent) form of cell source. Based on this principle, different cells can embedded individually like an individual account, and different cell cultures can be together to form a “Cell Bank”.
It is contemplated that a variety of cell lines can be collected and embedded in paraffin blocks 34. Cultured cells may first be embedded in paraffin by conventional or by the above-described methods.
A portion of the paraffin embedded cells may then be taken out by various methods (e.g., by use of transfer tube 26 and tamp 28) and re-embedded in a paraffin block 34 as above-described to generate paraffin-embedded cell blocks 34 in a fashion of tissue microarray. It is preferred that the method of embedding including the embedding tray and partitioned tray insert is utilized to create the cell array.
Various types of arrays could be created by the above described method. By way of example, and not limitation, these types of arrays include embryonic cell array, adult cell array, primary cell array, cell line array, tissue array, mammalian array, zoo array, personal cell array, genetically altered array, chemically treated array, or disease cell array. Further it is contemplated to create a cell array by the above described method wherein the different cell mixtures differ in one or more of the characteristics selected from the group consisting of genotypic characteristics, species, origin, developmental stage, developmental origin, tissue origin, chemical treatment, cell-cycle point and disease state.
The blocks 34 may contain different combinations of different cells from different systems and organs. By way of example and not limitation, different breast cancer cell lines can be provided in one block, different carcinoma cell lines in one block, different sarcoma cell lines in one block, different benign cell lines in one block, different epithelial cell lines in one block, and different mesenchymal cell lines in one block. It is also contemplated to create a cell array with cell populations from several different types of body tissues in one cell array, the tissues including but not limited to blood, muscle, nerve, brain, heart, lung, liver, pancreas, spleen, thymus, esophagus, stomach, intestine, kidney, testes, ovary, hair, skin, bone, breast, uterus, bladder, spinal cord, and body fluids.
Cells from many cell lines, including cells from primary cultures, cells from humans, rats, mice, and other animals, cells from different organisms, and cells from an organism at different stages of development, may thereby be provided in a single cell block. The cells may be treated with different conditions (different chemicals, different temperatures, different culture conditions, etc.) based on specific requirements, collected, and embedded in a single block 34.
A variety of cell lines may be maintained as a “cell bank” and blocks 34 containing specific cell lines may be pre-formed and provided as “ready to use” blocks 34 to researchers or others. Pre-made blocks 34 including the desired embedded specimens or cell lines may be customized (e.g., specific cell line(s) and number of wells) and manufactured according to the user's specific needs.
Sections can then be generated from different blocks 34 and slides containing the cells from these sections can be obtained and processed as desired, e.g., protein, DNA, RNA, or other studies.
The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/630,870, filed 24 Nov. 2004, and entitled “Cytoblock Preparation System and Methods of Use.”
Number | Date | Country | |
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60630870 | Nov 2004 | US |