High throughput methods, systems and apparatus for performing cell based screening assays

• US 6,529,835 B1
• Filed: 06/26/2000
• Issued: 03/04/2003
• Est. Priority Date: 06/25/1998
• Status: Expired due to Term

• Current Assignee: Caliper Holdings Incorporated
• Original Assignee: Caliper Holdings Incorporated
• Inventors: Wada, H. Garrett, Sundberg, Steven A.
• Primary Examiner(s): Hilten, John S.
• Assistant Examiner(s): Washburn, Douglas N
• Application Number:
  US09/604,785
• Time in Patent Office: 981 Days
• Field of Search: 156/655.1, 204/182.8, 204/299.R, 204/450, 204/451, 204/454, 204/601, 210/198.2, 216/33, 356/344, 417/48, 422/63, 422/82.05, 422/102, 422/104, 435/4, 435/91.2, 436/514, 548/236, 702/19, 702/21
• US Class Current: 702/21
• CPC Class Codes: B01L 2200/14 Process control and prevention of errors
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: G01N 33/5005 involving human or animal cells immunoassay G01N33/56966; immunoassays of protozoa G01N33/56905; protozoa in screening assays C12Q1/025
• CPC Class Codes: G01N 33/56972 White blood cells

Abstract

Methods for determining a function of cells, which comprises a suspension of cells flowing along a first fluid channel. The cells have a first detectable property associated therewith, and wherein the cells produce a second detectable property upon activation of the function of the cells, the first and second detectable properties being distinguishable from each other. Levels of the first and second detectable properties are measured. The level of the second detectable property is compared to the level of first detectable property to determine the relative function of the cells.

Claims

1. A computer implemented method of determining a level of function of cells, comprising:

receiving first signals corresponding to a first detectable property of the cells in a suspension flowing along a fluid channel;

receiving second signals corresponding to a second detectable property produced by the cells upon activation of the function of the cells; and

determining the level of the function of the cells by comparing the first and second signals.

2. The method of claim 1, wherein comparing the first and second signals includes calculating a ratio of the first and second signals, the ratio being indicative of the level of function of the cells.

3. The method of claim 1, further comprising displaying the level of the function of the cells to a user.

4. The method of claim 1, wherein the first and second signals are received simultaneously.

5. The method of claim 1, wherein the fluid channel includes a test compound, wherein the level of function of the cells is determined in the presence of the test compound.

6. The method of claim 5, further comprising determining an effect of the test compound on the level of the function of the cells by comparing the level of the function of the cells to a reference level of function of the cells.

7. The method of claim 5, further comprising displaying the effect of the test compound to a user.

8. The method of claim 5, further comprising introducing the test compound into the fluid channel.

9. The method of claim 1, wherein the fluid channel includes a plurality of different test compounds, wherein the level of function of the cells is separately determined in the presence of each of the different test compounds.

10. The method of claim 9, further comprising determining an effect of each different test compound on the level of the function of the cells by comparing the level of the function of the cells to a reference level of function of the cells.

11. The method of claim 9, further comprising displaying the effect of each of the different test compounds to a user.

12. The method of claim 9, further comprising introducing the different test compounds serially into the fluid channel.

13. The method of claim 1, further comprising applying a pressure differential along the fluid channel to flow the suspension of cells along the fluid channel.

14. The method of claim 1, further comprising applying an electric field along a length of the fluid channel, the electric field being sufficient to cause electrokinetic flowing of the suspension of cells along the fluid channel.

15. The method of claim 1, further comprising applying an inertial force to the suspension of cells to cause the suspension of cells along the fluid channel.

16. The method of claim 1, further comprising measuring the first and second detectable properties of the cells.

17. The method of claim 16, wherein the first and second detectable properties of the cells are measured simultaneously.

18. The method of claim 1, wherein the function of the cells is selected from binding functions, transport functions, expression functions, and viability.

19. A computer program product for determining a level of function of cells, comprising:

computer code that receives first signals corresponding to a first detectable property of the cells in a suspension flowing along a fluid channel;

computer code that receives second signals corresponding to a second detectable property produced by the cells upon activation of the function of the cells;

computer code that determines the level of the function of the cells by comparing the first and second signals; and

a computer readable medium that stores the computer codes.

20. The computer program product of claim 19, wherein the computer readable medium is a CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, or data signal embodied in a carrier wave.

21. A system, comprising:

a microfluidic device having a fluid channel;

at least one detector for measuring at least one detectable property in the fluid channel; and

a computer system that controls the flow of a suspension of cells along the fluid channel and receives signals from the at least one detector, the computer system executing a program stored on a computer readable medium comprising;

computer code that receives first signals corresponding to a first detectable property of the cells in a suspension flowing along a fluid channel;

computer code that receives second signals corresponding to a second detectable property produced by the cells upon activation of the function of the cells; and

computer code that determines the level of the function of the cells by comparing the first and second signals.

22. The system of claim 21, wherein the computer readable medium is a CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, or data signal embodied in a carrier wave.

23. A computer implemented method of determining a binding function of cells, comprising:

receiving first signals corresponding to a detectable property of the cells in a suspension flowing along a binding region of a fluid channel in the presence of a test compound, the binding region having a binding moiety immobilized on an interior surface of the fluid channel and the cells including on their surfaces a moiety bound by the binding moiety;

calculating a velocity of the cells flowing through the binding region by analyzing the first signals; and

determining an effect of the test compound on the binding function of the cells by comparing the velocity to a reference velocity.

24. The method of claim 23, wherein the reference velocity is of the cells flowing along the binding region of the fluid channel in the absence of the test compound.

25. The method of claim 24, wherein the fluid channel includes a non-binding region having substantially no binding moiety immobilized therein.

26. The method of claim 25, further comprising:

receiving second signals corresponding to the detectable property of the cells in the suspension flowing along the non-binding region of the fluid channel in the presence of the test compound; and

calculating the reference velocity by analyzing the second signals.

27. The method of claim 23, further comprising flowing the suspension of cells along the fluid channel.

28. The method of claim 27, wherein flowing the suspension of cells along the fluid channel includes pulsing groups of cells through the fluid channel.

29. The method of claim 27, wherein flowing the suspension of cells along the fluid channel includes applying a pressure differential across the length of the fluid channel.

30. The method of claim 29, wherein applying the pressure differential includes applying a hydrostatic pressure to one end of the fluid channel.

31. The method of claim 29, wherein applying the pressure differential includes applying an electroosmotically driven pressure to one end of the fluid channel.

32. The method of claim 23, wherein calculating a velocity of the cells flowing through the binding region includes:

determining a time difference between when the first signals indicate the cells passed first and second points on the fluid channel, the first and second points being spaced apart along the fluid channel; and

calculating the velocity from the time difference and a distance along the fluid channel between the first and second points.

33. The method of claim 23, further comprising introducing the test compound into the fluid channel.

34. The method of claim 23, further comprising displaying the effect of the test compound on the binding function of the cells to a user.

35. The method of claim 23, wherein the effect is that the test compound is an inhibitor of the binding function of the cells if the velocity is less than the reference velocity and the effect is that the test compound is an enhancer of the binding function of the cells if the velocity is less than the reference velocity.

36. The method of claim 23, further comprising determining effects of a plurality of different test compounds on the binding function of the cells by analyzing velocities of cells flowing serially through the binding region in the presence of each of the different test compounds.

37. The method of claim 36, further comprising displaying the effect of each of the different test compounds to a user.

38. The method of claim 36, further comprising introducing the different test compounds serially into the fluid channel.

39. A computer program product for determining a binding function of cells, comprising:

computer code that receives first signals corresponding to a detectable property of the cells in a suspension flowing along a binding region of a fluid channel in the presence of a test compound, the binding region having a binding moiety immobilized on an interior surface of the fluid channel and the cells including on their surfaces a moiety bound by the binding moiety;

computer code that calculates a velocity of the cells flowing through the binding region by analyzing the first signals;

computer code that determines an effect of the test compound on the binding function of the cells by comparing the velocity to a reference velocity; and

a computer readable medium that stores the computer codes.

40. The computer program product of claim 39, wherein the computer readable medium is a CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, or data signal embodied in a carrier wave.

41. A system, comprising:

a microfluidic device having a fluid channel;

at least one detector for measuring at least one detectable property in the fluid channel; and

a computer system that controls the flow of a suspension of cells along the fluid channel and receives signals from the at least one detector, the computer system executing a program stored on a computer readable medium comprising;

computer code that receives first signals corresponding to a detectable property of the cells in a suspension flowing along a binding region of a fluid channel in the presence of a test compound, the binding region having a binding moiety immobilized on an interior surface of the fluid channel and the cells including on their surfaces a moiety bound by the binding moiety;

computer code that calculates a velocity of the cells flowing through the binding region by analyzing the first signals; and

computer code that determines an effect of the test compound on the binding function of the cells by comparing the velocity to a reference velocity.

42. The system of claim 41, wherein the computer readable medium is a CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, or data signal embodied in a carrier wave.