WO2017034940A1

WO2017034940A1 - Coverslip removal systems and methods

Info

Publication number: WO2017034940A1
Application number: PCT/US2016/047684
Authority: WO
Inventors: Rene Benson SKONE
Original assignee: Skone Rene Benson
Priority date: 2015-08-21
Filing date: 2016-08-19
Publication date: 2017-03-02

Abstract

Systems for removing coverslips preferably include a substantially planar base and at least one slide assembly that is disposed upon said substantially planar base. The substantially planar base comprises a sample of mammalian tissue that is disposed upon a substantially rigid support layer and a coverslip that is bound to the sample. The systems of the invention preferably also include a heat source that is in thermal communication with the slide assembly.

Description

COVERSLIP REMOVAL SYSTEMS AND METHODS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the priority of U.S. Provisional Patent Application No. 62/208,229 filed August 21, 2015, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The methods and systems described herein may have applications in the fields of Anatomic Pathology, Histology, and Immunohistochemistry (IHC). More specifically, the system and methods described herein may be used to facilitate the removal of coverslips from stained slides of, for example, human tissue specimens.

BACKGROUND

[0003] Before examining tissue under a microscope, it is a common practice to use stains, which make tissue components visible. In today's fast-paced fields of surgery and anatomic pathology, many labs have turned to automated staining systems to satisfy the need for high processing volume of microscope slides. In these automated slide staining systems, such as the Tissue-Tek Prisma Automated Slide Stainer from Sakura Finetek USA, Inc., Torrance, CA, stains are automatically applied to slides having tissue specimens on them.

[0004] Once slides have been stained, coverslips are applied to them so that they can be placed under the microscope. Coverslips can be applied manually, but this adds further delay. Hence, the coverslipping process is also becoming automated. Coverslip application machines, such as the Leica CV5030 Coverslipper from Leica Biosystems Inc., Buffalo Grove, IL, have been created to interface with automatic staining machines. Additionally, newer systems are combining the staining and coverslipping process into a single, automatic machine or system. An example of this can be seen in the Symphony System from Ventana Medical Systems, Inc., Tucson, AZ.

[0005] One difficulty with automatic coverslipping machines is that they cure the coverslips to the stained slides. This curing mounts the coverslip to the slide such that it cannot be removed either at all or without seriously damaging the tissue underneath. This is a problem for pathologists because coverslip removal is necessary in many situations, including when a pathologist needs to diagnose cancer in the tissue sample. Coverslip removal may also be necessary for other reasons, such as if a slide has been improperly stained. Additionally, a batch of coverslips may be misaligned when placed onto stained slides and, rather than discard the resulting slides, it might be easier to remove and re-apply the coverslips.

[0006] Before automatic coverslip machines started curing coverslips to slides, coverslip removal typically was accomplished by soaking the slides in xylene or other suitable solvent. Solvents, however, generally are not able to aid with the removal of cured coverslips. Accordingly, there exists a need to remove coverslips from slides after automatic staining and coverslipping has been accomplished.

SUMMARY

[0007] One aspect of the present invention is directed to methods for removing a coverslip from a sample of mammalian tissue such as, for example, a sample disposed on a slide. Representative methods involve providing at least one slide assembly comprising both a sample of mammalian tissue that is disposed upon a substantially rigid support layer and a coverslip that is bound to the sample. Heat is applied to the slide assembly for a time and under conditions effective to reduce adhesion between the sample and the coverslip, and the coverslip is removed from the sample.

[0008] The present invention also provides systems for removing a coverslip from a tissue sample that is disposed upon a substantially rigid support layer. Representative systems include a substantially planar base with at least one slide assembly disposed upon it. The slide assembly comprises a sample of mammalian tissue that is disposed upon a substantially rigid support layer, a coverslip that is bound to the sample, and a heat source that is in thermal communication with the slide assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Fig. 1 is

[0010] Fig. 2 is

[0011] Fig. 3 is

[0012] Fig. 4 is

[0013] Fig. 5 is

[0014] Fig. 6 is

coverslips;

[0015] Fig. 7 is a side view of the system shown in Fig. 6; and

[0016] Fig. 8 is a bottom view of the system shown in Fig. 6. DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0017] As illustrated in Fig. 2, a system for removing coverslips 10 includes a substantially planar base 12 and at least one slide assembly 14 that is disposed upon said substantially planar base 12. As shown in Figs. 1 and 3, the slide assembly 14 will comprise a sample of mammalian tissue 16 that is disposed upon a substantially rigid support layer 18 and a coverslip 20 that is bound to the sample 16. As shown in Figs. 2-3, system 10 includes heat source 22 that is in thermal communication with slide assembly 14 when activated. Once slide assembly 14 is in position, heat can be applied from heat source 22 to slide assembly 14 for a time and under conditions effective to reduce adhesion between sample 16 and coverslip 20. Afterwards, coverslip 20 may be removed from sample 16.

[0018] As shown in Figs. 2-3, housing 24 may at least partially contain the base 12, the slide assembly 14, and the heat source 22. Housing 24 can be made out of molded plastic, steel, or other material capable of housing heating elements. Hinge 26 is a movable surface that provides access to slide assembly 14. Hinge 26 also allows for housing 24 to be closed during the heating process, which provides increased safety. Slide assembly 14 preferably is loaded onto base 12 such that the side of support layer 18 with sample 16 on it is facing upwards. The base 12 can be adapted to make loading the slide assembly 14 into housing 24 easier. For example, the base 12 can be in the form of a tray or can be adapted to extend outside of housing 24. Further, as shown in Fig. 6, base 112 may have guides 128 that restrict movement of slide assembly 114 so that it is substantially immobile during the heating process.

[0019] Figs. 6-7 also show that slide assembly 114 can be loaded onto base 112 such that part 130 of slide assembly 114 remains outside of housing 124. In this case, heat source 122 would only be applied to part 132 of slide assembly 114, which is the part that is under housing 124. This will facilitate the removal of slide assembly 114 from heat source 122 because a user can handle part 130 manually without burning his fingers. However, in alternative embodiments, the slide assembly can be placed entirely under the housing so that heat is applied to the entire assembly. In that case, the removal of the slide assembly could be accomplished through the use of tongs, forceps, or any other laboratory equipment.

[0020] Referring to Figs. 1-3, once slide assembly 14 is removed from heat source 22, coverslip 20 can be removed by sliding it off of sample 16, or by any other technique detailed in a standard laboratory guide or by laboratory protocols. Care generally must be taken when removing coverslip 20 from sample 16, and one typically should not hastily pull, peel, or yank back coverslip 20. If the coverslip 20 is not removed from sample 16 properly, there is the potential for damage to the underlying mammalian tissue, which could reduce or eliminate the tissue's usefulness for further pathology studies. Once coverslip 20 is removed from sample 16, sample 16 should remain on support layer 18, and together they can be immersed in a solvent, such as xylene, to remove any remaining residue. Afterwards, sample 16 can be re-hydrated to remove any stain thereon. Alternatively, sample 16 can be covered with a new coverslip.

[0021] Support layer 18 and coverslip 20 may be made of glass or some type of suitable polymeric material. For example, coverslip 20 may by a Symphony Optisure Glass Coverslip from Ventana Medical Systems, Inc., Tucson, AZ. Coverslip 20 may be bound to sample 16 with an adhesive, such as one comprising cyanoacrylate. The sample 16 can be human tissue, cat tissue, dog tissue, or any other mammalian tissue. Sample 16 may also bear a stain (not shown) to help facilitate viewing it under a microscope. This stain can be a Haematoxylin stain, an Eosin stain, or a Special Stain. These Special Stains, identified by Current Procedural Terminology (CPT) codes 88312 and 88313, may include, for example, Gomori Methenamine Silver (GMS) stains, Acid-Fast Bacilli (AFB) stains, Periodic Acid-Schiff (PAS) stains, or Iron (Fe) stains.

[0022] Heat source 22 may be a direct heat source, a radiant heat source, a source of microware energy, a source of ultraviolet energy, an indirect heat source, or any other source capable of providing heat to thereby reduce adhesion between sample 16 and coverslip 20.

Further, heat source 22 may employ convective style heating, which will include the use of a fan (not shown).

[0023] Heat source 22 according to the present invention applies heat to slide assembly 14 for a time and under conditions effective to reduce adhesion between sample 16 and coverslip 20. In certain embodiments, temperatures at which slide assembly 14 can be heated range from about 54° C to about 109° C, preferably about 77° C to about 109° C, more preferably about 91° C to about 109° C. At these temperatures, slide assembly 14 typically is heated for about 15 seconds to about 75 seconds, preferably about 15 seconds to about 60 seconds, more preferably about 15 seconds to about 35 seconds. If slide assembly 14 contains a larger sample 16, it may need to be heated at a higher temperature for a longer time, whereas if slide assembly 14 contains a smaller sample 16, it may need to be heated at a lower temperature for a shorter time.

[0024] As shown in Figs. 3 and 6, heat source 22 or 122 may include a heated surface that is made from, for example, ceramic, tile, or metal. Further, heat source 22 may be powered by an electrically resistive element 34, as shown in Fig. 5. This element 34 may also be made from metal, plastic, or ceramic and may include heater coil 36. Element 34 may also be of the type that can heat the heated surface to a residual desired heat, such as the Minco 0121 HR5170- 107 Press Sensitivity Pad from Minco, Minneapolis, MN. Further, element 34 may be a Lexan plastic molded heating element, supplying 13 -watts of electricity. Fig. 8 shows an alternative arrangement for heater coil 136, which is disposed on element 134. Heater coil 136 may be made out of metal wire, such as nichrome, or other similar materials.

[0025] Heat source 122 may also communicate with a thermostat (not shown) and/or various displays. For example, in Fig. 6, system 110 includes indicator 138, which could be in the form of an LCD or LED display. The indicator 138 could be used to relay system information. For example, indicator 138 could be used to indicate the temperature of heat source 122, the temperature of slide assembly 114, or the time associated with exposure of slide assembly 1 14 to heat source 122. Additionally in Fig. 6, system 1 10 includes dial 140, which can be used to control the temperature of heat source 122.

[0026] As shown in Fig. 6, a light source 142 such as a light bulb or diode may also be in visual communication with slide assembly 1 14 such that a user can view the slide assembly 1 14 while heat source 122 is in thermal communication with it. Light source 142 may also be used to view slide assembly 1 14 while it is being placed onto base 1 12, or otherwise being arranged. Light switch 144 can be used to turn light source 142 on and off.

[0027] As seen in Figs. 6-7, system 1 10 may also include a power control 146 and a power cord 148. The power control 146 will turn heat source 122 on and off. Power cord 148 can include a standard plug such as, for example, a 110-volt plug. Power control 146 may also be in communication with a display 150 such that the display 150 indicates when the power is on or off, as shown in Fig. 6. This display 150 can be in the form of an LCD or LED display. Power control 146 can also be equipped with an automatic-off feature such that system 1 10 turns off after a predetermined amount of time to account for safety concerns and to conserve electricity.

[0028] The embodiments shown in the figures and described above illustrate aspects of the present invention. The present invention is not limited to the particular embodiments shown in the figures, but encompasses structures and methods broader than the disclosure and limited only by the claims.

Claims

What is Claimed:

1. A method comprising:

providing at least one slide assembly comprising a sample of mammalian tissue that is disposed upon a substantially rigid support layer and a coverslip that is bound to said sample; applying heat to said slide assembly for a time and under conditions effective to reduce adhesion between said sample and said coverslip; and

removing said coverslip from said sample.

2. The method of claim 1 wherein said mammalian tissue is human tissue.

3. The method of claim 1 wherein said mammalian tissue bears a stain.

4. The method of claim 3 wherein said stain is a Haematoxylin stain, an Eosin stain, or a Special Stain.

5. The method of claim 4 wherein said Special Stain is a Gomori Methenamine Silver stain, an Acid-Fast Bacilli stain, a Periodic Acid-Schiff stain, or an Iron stain.

6. The method of claim 1 wherein said substantially rigid support layer comprises glass.

7. The method of claim 1 wherein said sample and said coverslip are bound with an adhesive.

8. The method of claim 7 wherein said adhesive comprises cyanoacrylate.

9. The method of claim 1 wherein said heat is applied by exposing said slide assembly to a radiant heat source.

10. The method of claim 9 wherein said radiant heat source is an electrically resistive element.

1 1. The method of claim 1 wherein said heat is applied by exposing said slide assembly to a source of microwave energy.

12. The method of claim 1 wherein said heat is only applied to a part of said slide assembly such that there is an unheated portion.

13. The method of claim 12 further comprising removing said slide assembly from said heat by handling said unheated portion following said applying step.

14. The method of claim 1 further comprising removing said slide assembly from said heat through the use of tongs or forceps following said applying step.

15. The method of claim 1 wherein said coverslip is removed by sliding it off of said sample.

16. The method of claim 1 further comprising immersing said sample of mammalian tissue that is disposed upon said substantially rigid support layer in solvent after removing said coverslip step.

17. The method of claim 16 wherein said solvent is xylene.

18. The method of claim 1 further comprising re-disposing said coverslip on said sample following said removing said coverslip step.

19. The method of claim 1 wherein said time ranges from about 15 seconds to about 75 seconds and said heat is applied at a temperature ranging from about 54° C to about 109° C.

20. The method of claim 1 , wherein said time ranges from about 15 seconds to about 60 seconds and said heat is applied at a temperature ranging from about 77° C to about 109° C.

21. The method of claim 1 , wherein said time ranges from about 15 seconds to about 35 seconds and said heat is applied at a temperature ranging from about 91° C to about 109° C.

22. A system comprising:

a substantially planar base;

at least one slide assembly that is disposed upon said substantially planar base and, in turn, comprises a sample of mammalian tissue that is disposed upon a substantially rigid support layer and a coverslip that is bound to said sample; and

a heat source in thermal communication with said slide assembly.

23. The system of claim 22 further comprising a housing that at least partially contains said substantially planar base, said slide assembly and said heat source.

24. The system of claim 23 wherein said housing includes at least one movable surface that provides access to at least said slide assembly.

25. The system of claim 23 wherein said substantially planar base is adapted to extend outside said housing.

26. The system of claim 22 wherein said substantially planar base is a tray.

27. The system of claim 22 wherein said substantially planar base includes guides that restrict movement of said slide assembly.

28. The system of claim 22 wherein said mammalian tissue is human tissue.

29. The system of claim 22 wherein said mammalian tissue bears a stain.

30. The system of claim 29 wherein said stain is a Haematoxylin stain, an Eosin stain, or a Special Stain.

31. The system of claim 30 wherein said Special Stain is a Gomori Methenamine Silver stain, an Acid-Fast Bacilli stain, a Periodic Acid-Schiff stain, or an Iron stain.

32. The system of claim 22 wherein said substantially rigid support layer comprises glass.

33. The system of claim 22 wherein said sample and said coverslip are bound with an adhesive.

34. The system of claim 33 wherein said adhesive comprises cyanoacrylate.

35. The system of claim 22 wherein said heat source is a direct heat source, a radiant heat source, a source of microwave energy, a source of ultraviolet energy, or an indirect heat source.

36. The system of claim 22 wherein said heat source is an electrically resistive element.

37. The system of claim 36 wherein said element comprises metal, plastic, or ceramic.

38. The system of claim 22 wherein said heat source is in communication with a fan.

39. The system of claim 22 wherein said heat source is in communication with a thermostat.

40. The system of claim 22 wherein said heat source is in communication with a display.

41. The system of claim 40 wherein said display reports system information comprising a temperature associated with said heat source, a temperature associated with said slide assembly, or a time associated with exposure of said slide assembly to said heat source.

42. The system of claim 22 further comprising a light source in visual communication with said slide assembly.

43. The system of claim 22 further comprising a power control in communication with said heat source.

44. The system of claim 22 further comprising said heat source in thermal communication with said slide assembly for about 15 seconds to about 75 seconds at a temperature ranging from about 54° C to about 109° C.

45. The system of claim 22 further comprising said heat source in thermal communication with said slide assembly for about 15 seconds to about 60 seconds at a temperature ranging from about 77° C to about 109° C.

46. The system of claim 22 further comprising said heat source in thermal communication with said slide assembly for about 15 seconds to about 35 seconds at a temperature ranging from about 91° C to about 109° C.