Methods and devices for complexing target entities
A method of recovering a population of extracellular vesicles from a biological sample comprising extracellular vesicles and contaminants is described. In one embodiment, the method comprises: a) removing contaminants from the sample, wherein the contaminants are relatively larger or more dense than the extracellular vesicles; b) contacting the sample of step a) with a plurality of binding compositions, each binding composition having first and/or second moieties capable of binding a recognition motif of the target entities under conditions to allow complexing of the extracellular vesicles with the plurality of binding compositions to form a complexed population of extracellular vesicles, the complexed population of extracellular vesicles having an increased volume and/or higher density in comparison to the extracellular vesicles in individual form; and c) recovering the complexed population of extracellular vesicles.
1. A method of recovering a population of extracellular vesicles from a biological sample comprising extracellular vesicles and contaminants, the method comprising:
a) removing contaminants from the sample, wherein said contaminants are larger or more dense than the extracellular vesicles;
b) contacting the sample of step a) with a plurality of binding compositions, each binding composition having first and/or second moieties linked by third and fourth moieties, wherein the first and/or second moieties bind a recognition motif of extracellular vesicles under conditions to allow aggregation of the extracellular vesicles and the plurality of binding compositions to form a complexed population of extracellular vesicles, the complexed population of extracellular vesicles having an increased volume and/or higher density in comparison to the extracellular vesicles in individual form and wherein the complexed population of extracellular vesicles is formed without reliance on physical components other than the plurality of binding compositions; and
c) recovering the complexed population of extracellular vesicles, wherein the recognition motif is one or more of CD9, CD63, and CD81 and wherein the first, second, third, and fourth moieties are antibodies or fragments thereof.
2. The method according to claim 1 , wherein the population of extracellular vesicles is homotypic.
3. The method according to claim 2 , wherein the first and second moieties bind the same or different recognition motif.
4. The method according to claim 1 , wherein the plurality of binding compositions are at below-saturation levels.
5. The method according to claim 1 , wherein the sample further comprises non-target entities.
6. The method according to claim 5 , further comprising after step c) fractionating the complexed population of extracellular vesicles from non-target entities.
7. The method according to claim 6 , further comprising recovering specifically the fractionated non-target entities.
8. The method according to claim 7 , wherein recovering specifically the fractionated non-target entities comprises complexing the fractionated non-target entities with a second plurality of binding compositions to form a complexed population of non-target entities, the complexed population of non-target entities having an altered physical property in comparison to the target-entities in individual form.
9. The method according to claim 7 , wherein the non-target entities are microvesicles or exosomes not presenting the one or more recognition motifs.
10. The method according to claim 1 , wherein the contaminants comprise one or more of cells, cellular debris, organelles, macromolecules, or breakdown products of any of the foregoing.
11. The method according to claim 1 , wherein the extracellular vesicles are microvesicles or exosomes.
12. The method according to claim 1 , wherein the physical components are particle, beads, or polymers.