Methods of donor specific crossmatching

1. A method of cross-matching a donor and a recipient comprising:

(a) providing a donor sample containing, or suspected of containing, a precursor endothelial cell;

(b) contacting the donor sample with a detection reagent to isolate the endothelial cell under conditions where the precursor endothelial cell and the detection reagent are capable of forming a complex;

(c) separating said complex from the sample, thereby isolating said precursor endothelial cell from said biological sample;

wherein the isolated precursor endothelial cell is CD34 negative and CD14 positive; and

(d) screening a recipient sample for a reactivity with the isolated precursor endothelial cell wherein no reactivity of the recipient sample with the isolated precursor endothelial cell indicates compatibility between the donor and recipient.

2. The method of claim 1 , wherein the detection reagent is a ligand for an endothelial cell surface receptor.

3. The method of claim 2 , wherein said ligand is angiopoietin or VEGF.

4. The method of claim 1 , wherein the detection reagent is an antibody, or Fab or Fv fragment thereof.

5. The method of claim 4 , wherein the antibody is specific against an endothelial cell receptor.

6. The method of claim 5 , wherein the endothelial cell receptor is Tie-2 or VEGFR-1.

7. The method of claim 4 , wherein the antibody or Fab or Fv fragment thereof is attached to a solid support.

8. The method of claim 7 , wherein the solid support is a non-magnetic, magnetic or a paramagnetic bead.

9. The method of claim 1 , wherein the isolated endothelial cell is Tie-2 positive or VEGFR-1 positive.

10. The method of claim 1 , wherein the donor sample or recipient sample is selected from the group consisting of whole blood, sera, tissue, peripheral blood, mononuclear cells, and leucapherisate.