METHODS AND SYSTEMS FOR CELL SEPARATION USING MAGNETIC-AND SIZE-BASED SEPARATION

• US 20170268037A1
• Filed: 05/15/2015
• Published: 09/21/2017
• Est. Priority Date: 05/15/2014
• Status: Abandoned Application

• Current Assignee: Fluxion Biosciences Incorporated
• Original Assignee: Fluxion Biosciences Incorporated
• Inventors: IONESCU-ZANETTI, CRISTIAN, SCHWARTZ, MICHAEL, FU, CHRISTINE TING, FAN, RONG ANDREA
• Application Number:
  US15/310,083
• Publication Number:
  US 20170268037A1
• Time in Patent Office: Days
• CPC Class Codes: B01L 2200/0652 Sorting or classification of particles or molecules
• CPC Class Codes: B01L 2400/043 magnetic forces
• CPC Class Codes: B01L 3/502761 specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules investigating characteristics of particles G01N15/00
• CPC Class Codes: B03C 1/01 by addition of magnetic adjuvants
• CPC Class Codes: B03C 1/0332 using permanent magnets
• CPC Class Codes: B03C 1/288 disposed at the outer circumference of a recipient
• CPC Class Codes: B03C 1/30 Combinations with other devices, not otherwise provided for
• CPC Class Codes: B03C 2201/18 Magnetic separation whereby the particles are suspended in a liquid
• CPC Class Codes: B03C 2201/26 for use in medical or biological applications
• CPC Class Codes: C12M 47/02 Separating microorganisms from the culture medium; Concentration of biomass separating microorganisms from their culture media C12N1/02
• CPC Class Codes: C12N 11/14 Enzymes or microbial cells immobilised on or in an inorganic carrier
• CPC Class Codes: C12Q 1/6806 Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay C12Q1/6804 takes precedence
• CPC Class Codes: C12Q 2563/143 Magnetism, e.g. magnetic label
• CPC Class Codes: C12Q 2563/149 Particles, e.g. beads
• CPC Class Codes: G01N 33/54326 Magnetic particles

Abstract

A method is provided including coupling magnetic beads to a population of cells in a fluid sample to form magnetically-labeled cells, magnetically separating the magnetically-labeled cells from non-magnetically-labeled cells in the fluid sample, and separating target cells from non-target cells of the magnetically-labeled cells based on a size difference between the magnetically-labeled target cells and the magnetically-labeled non-target cells. A microfluidic device is provided including a fluidic pathway traversing a magnetic isolation region and a size-based isolation region. The magnetic isolation region includes a magnet positioned to separate magnetically-labeled cells from non-magnetically labeled cells in the magnetic isolation region. The size-based isolation region includes a separator configured to separate cells less than a threshold size from cells greater than a threshold size.

Claims

1. A method comprising:

coupling beads to a population of target cells based on antibody binding in a fluid sample to form target cell-bead aggregates having a larger size than a population of non-target cells in the fluid sample; and

separating the target cell-bead aggregates from the non-target cells based on a size difference between the target cell-bead aggregates and the non-target cells.

2. The method of claim 1, further comprising magnetically separating the target cell-bead aggregates from the non-target cells in the fluid sample.

3. The method of claim 2, further comprising sequencing DNA or mRNA from the target cell-bead aggregates.

16. The method of claim 1, wherein the target cells are tumor cells.

4. A method comprising:

coupling magnetic beads to a population of cells in a fluid sample to form magnetically-labeled cells, wherein certain of the magnetically-labeled cells are target cells and others of the magnetically-labeled cells are non-target cells;

magnetically separating the magnetically-labeled cells from non-magnetically-labeled cells in the fluid sample; and

separating the target cells from the non-target cells of the magnetically-labeled cells based on a size difference between the magnetically-labeled target cell-bead aggregates and the magnetically-labeled non-target cells.

5. The method of claim 4, further comprising sequencing DNA or mRNA from the magnetically-labeled target cells.

6. The method of claim 5, wherein the magnetic separation step comprises immobilizing the magnetically-labeled cells on an inner surface of a microfluidic device during flow of the fluid sample through a fluidic pathway of the microfluidic device.

7. The method of claim 6, further comprising flowing a portion of the fluid sample through a separator disposed downstream of the immobilized magnetically-labeled cells.

8. The method of claim 7, further comprising:

releasing the magnetically-labeled cells from the inner surface of the microfluidic device; and

flowing the magnetically-labeled cells toward the separator.

9. The method of claim 7, wherein the separating the target cells from the non-target cells step comprises capturing the magnetically-labeled target cells on an upstream surface of the separator.

11. The method of claim 6, wherein the immobilizing step comprises immobilizing the magnetically-labeled cells on a bottom surface of a removable section of the fluidic pathway of the microfluidic device.

12. The method of claim 11, further comprising:

removing the removable section with the immobilized magnetically-labeled cells from the microfluidic device; and

placing the magnetically-labeled cells on top of a separator.

13. The method of claim 12, wherein the separating the target cells from the non-target cells step comprises capturing the magnetically-labeled target cells on a top surface of the separator.

14. The method of claim 11, further comprising sequencing DNA or mRNA from the magnetically-labeled target cells.

15. The method of claim 4, wherein the fluid sample is a blood sample, and further comprising separating a buffy coat from the blood sample prior to coupling magnetic beads to the population of cells.

10. The method of 6, further comprising sequencing DNA or mRNA from the magnetically-labeled target cells.

17. A microfluidic device comprising:

an input;

an output; and

a fluidic pathway extending between the input and the output, the fluidic pathway traversing a magnetic isolation region and a size-based isolation region, wherein the magnetic isolation region includes a magnet positioned to separate magnetically-labeled cells from non-magnetically labeled cells in the magnetic isolation region, and wherein the size-based isolation region is downstream of the magnetic isolation region and includes a separator configured to separate cells less than a threshold size from cells greater than a threshold size, wherein the threshold size is greater than a size of some magnetically-labeled non-target cells but less than a size of some magnetically-labeled target cells.

18. The microfluidic device of claim 17, wherein the threshold size is greater than a size of a majority of the magnetically-labeled non-target cells but less than a size of a majority of the magnetically-labeled target cells.

19. The microfluidic device of claim 17, wherein the magnetic isolation region includes a removable wall section of the microfluidic device.

20. The microfluidic device of claim 17, wherein the separator extends across an entire cross section of the fluidic pathway.

21. The microfluidic device of claim 17, wherein the separator defines multiple apertures extending lengthwise parallel to a direction of fluid flow in the fluidic pathway.