Kits, compositions and methods for cell enrichment

1 . A kit for one-step enrichment of myeloid-derived suppressor cells (MDSCs) from a sample comprising target cells and MDSCs, the kit comprising:

a plurality of antibodies or fragments thereof that bind target cells;

a blocking agent that blocks unintended binding of the antibodies or fragments thereof by Fc receptors expressed on the target cells; and

a plurality of particles, wherein the plurality of particles are linked or linkable to at least one of the antibodies or fragments thereof,

wherein the kit recovers at least 40% of the MDSCs in the sample at a purity of about 70% or higher of the MDSCs, as assessed by flow cytometry,

wherein the target cells comprise B cells, T cells, NK cells, dendritic cells, mast cells, granulocytes, red blood cells, and hematopoietic progenitors, and

wherein the plurality of antibodies comprise

a) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-F480 antibody,

b) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, and an anti-cKit antibody,

c) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody,

d) an anti-CD8 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody, or

e) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody.

2 . A kit for one-step enrichment of myeloid-derived suppressor cells (MDSCs) from a sample comprising target cells and MDSCs, the kit comprising:

a plurality of antibodies or fragments thereof that bind target cells;

a blocking agent that blocks unintended binding of the antibodies or fragments thereof by Fc receptors expressed on the target cells; and

a plurality of particles, wherein the plurality of particles are linked or linkable to at least one of the antibodies or fragments thereof,

wherein the kit recovers at least 40% of the MDSCs in the sample at a purity of about 70% or higher of the MDSCs, as assessed by flow cytometry,

wherein the target cells comprise B cells, T cells, NK cells, dendritic cells, monocytes/macrophages, mast cells, endothelial cells, granulocytes, red blood cells, and hematopoietic progenitors, and

wherein the plurality of antibodies comprise

a) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-F480 antibody,

b) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, and an anti-cKit antibody,

c) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody,

d) an anti-CD8 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody, or

e) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody.

3 . The kit according to claim 1 , wherein the plurality of antibodies or fragments thereof bind one or more antigens or epitopes thereof on the target cells, and wherein:

i) the B cell antigens are selected from B220, CD19, CD2, CD5, and CD31;

ii) the T cell antigens are selected from CD8, TCRγ/δ, TCRα/β, CD4, CD5, CD2, and CD31;

iii) the NK cell antigens are selected from CD49b and CD2;

iv) the dendritic cell antigens are selected from CD11c and CD31;

v) the mast cell antigen is cKit;

vi) the granulocyte antigen is CD31; and

vii) the red blood cell antigens are selected from Ter119 and CD24.

4 . The kit according to claim 1 , wherein the plurality of antibodies comprise a first linkage moiety.

5 . The kit according to claim 4 , wherein the plurality of particles comprise a second linkage moiety directly or indirectly linked or linkable to the first linkage moiety.

6 . The kit according to claim 5 , wherein the first linkage moiety is biotin, or any modification, derivative, or analogue thereof, and the second linkage moiety is streptavidin, or any modification, derivative, or analogue thereof.

7 . The kit according to claim 5 , wherein the kit further comprises a tetrameric antibody complex (TAC), wherein the TAC comprises a first antibody that binds to the first linkage moiety and a second antibody that binds to the second linkage moiety and the first antibody and the second antibody are indirectly linked.

8 . The kit according to claim 1 , wherein the plurality of particles are magnetic or magnetizable.

9 . A method for one-step enrichment of myeloid-derived suppressor cells (MDSCs) from a sample comprising target cells and MDSCs, the method comprising:

blocking unintended binding of a plurality of antibodies or fragments thereof by Fc receptors on the one or more target cells with a blocking agent;

contacting the sample with the plurality of antibodies or fragments thereof that bind one or more target cells, and a plurality of particles, wherein the plurality of particles are linked or linkable to at least one of the antibodies or fragments thereof;

incubating the target cells, antibodies or fragments thereof, and particles to form target cell:particle complexes; and

separating the target cell:particle complexes from the sample to enrich the MDSCs,

wherein the kit recovers at least 40% of the MDSCs in the sample at a purity of about 70% or higher of the MDSCs, as assessed by flow cytometry,

wherein the target cells comprise B cells, T cells, NK cells, dendritic cells, mast cells, granulocytes, red blood cells, and hematopoietic progenitors, and

wherein the plurality of antibodies comprise

a) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-F480 antibody,

b) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, and an anti-cKit antibody,

c) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody,

d) an anti-CD8 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-CD24 antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody, or

e) an anti-CD8 antibody, an anti-B220 antibody, an anti-Ter-119 antibody, an anti-CD49b antibody, an anti-CD19 antibody, an anti-CD11c antibody, an anti-TCRγ/δ antibody, an anti-TCRα/β antibody, an anti-CD4 antibody, an anti-CD5 antibody, an anti-CD2 antibody, an anti-cKit antibody, and an anti-CD31 antibody.

10 . The method according to claim 9 , wherein the target cells further comprise one or more of monocytes/macrophages, basophils, platelets, and endothelial cells.

11 . The method according to claim 10 , wherein the plurality of antibodies or fragments thereof bind one or more antigens or epitopes thereof on the target cells, and wherein:

i) the B cell antigens are selected from B220, CD19, CD2, CD5, and CD31:

ii) the T cell antigens are selected from CD8, TCRγ/δ, TCRα/β, CD4, CD5, CD2, and CD31;

iii) the NK cell antigens are selected from CD49b and CD2;

iv) the dendritic cell antigens are selected from CD11c and CD31:

v) the mast cell antigen is cKit;

vi) the granulocyte antigen is CD31; and

vii) the red blood cell antigens are selected from Ter119 and CD24.

12 . The method according to claim 9 , wherein the plurality of antibodies comprise a first linkage moiety.

13 . The method according to claim 12 , wherein the plurality of particles comprise a second linkage moiety directly or indirectly linked or linkable to the first linkage moiety.

14 . The method according to claim 13 , wherein the first linkage moiety is biotin, or any modification, derivative, or analogue thereof, and the second linkage moiety is streptavidin, or any modification, derivative, or analogue thereof.

15 . The method according to claim 9 , further comprising pre-linking the antibodies and particles before contacting the sample.

16 . The method according to claim 9 , wherein the plurality of particles are magnetic or magnetizable.

17 . The method according to claim 16 , further comprising exposing the target cell:particle complexes to a magnetic field.

18 . The method according to claim 9 , wherein the sample is a cell suspension.

19 . The method according to claim 18 , wherein the cell suspension is obtained from a tumour, spleen tissue, bone marrow tissue, or blood.

20 . The kit of claim 1 , wherein the target cells further comprise monocytes/macrophages and endothelial cells, and optionally one or more of basophils, and platelets.