Methods of capturing sperm nucleic acids

Patent metadata

Field	Value
Publication number	US-9957548-B2
Application number	US-201514672358-A
Country	US
Kind code	B2
Filing date	Mar 30, 2015
Priority date	Mar 30, 2015
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A method of capturing a sperm deoxyribo nucleic acid (DNA) in a sample is disclosed. The method includes a step of contacting a lysis solution to the sample that includes at least a sperm cell or a sperm cell lysate to lyse the sperm cell. The sperm cell or sperm cell lysate includes a protamine-DNA complex. The method further includes applying at least a protamine-specific antibody to the lysed sperm cell, wherein the protamine-specific antibody binds to the protamine-DNA complex of the lysed sperm cell to form an antibody-protamine-DNA complex. The method further includes capturing the antibody-protamine-DNA complex; and isolating and detecting the sperm DNA from the captured antibody-protamine-DNA complex.

First claim

What is claimed is:

1. A method of detecting a sperm deoxyribo nucleic acid (DNA) in a biological sample, comprising:
contacting a lysis solution to the biological sample comprising at least a sperm cell or a sperm cell lysate comprising a protamine-DNA complex to lyse the sperm cell, wherein the lysis solution comprises a detergent, and wherein the protamine-DNA complex remains intact after contacting the lysis solution;
applying a sequestration agent after the sperm cell lysis to sequester an excess detergent of the lysis solution;
applying at least a protamine-specific antibody to the lysed sperm cell after the sequestration of the excess detergent, wherein the protamine-specific antibody binds to the protamine-DNA complex of the lysed sperm cell to form an antibody-protamine-DNA complex;
capturing the antibody-protamine-DNA complex; and
detecting the sperm DNA from the captured antibody-protamine-DNA complex.

2. The method of claim 1 , further comprising removing or sequestering the lysis solution prior to applying the protamine-specific antibody.

3. The method of claim 1 , wherein the lysis solution comprises a reducing agent, and wherein the reducing agent is selected from dithiothreitol (DTT), tris(2-carboxyethyl)phosphine (TCEP), or a combination thereof.

4. The method of claim 1 , wherein the detergent is sodium dodecyl sulfate (SDS).

5. The method of claim 1 , wherein the lysis solution comprises 40 mM dithiothreitol (DTT), 0.5% to 2% sodium dodecyl sulfate (SDS), or combinations thereof.

6. The method of claim 1 , wherein the sequestration agent comprises ligand-activated core beads coated with size exclusion shell, alpha-cyclodextrin, size exclusion resin, or combinations thereof.

7. The method of claim 1 , wherein the protamine-specific antibody binds to the protamine-DNA complex during incubation in a temperature range from 4° C. to 37° C.

8. The method of claim 1 , wherein the protamine-specific antibody binds to the protamine-DNA complex during incubation at 4° C. for a time in a range from 10 minutes to 4 hrs.

9. The method of claim 1 , wherein the capturing of the antibody-protamine-DNA complex is achieved by a capturing agent, wherein the capturing agent is pre-coupled with the protamine-specific antibody.

10. The method of claim 9 , wherein the capturing agent comprises a secondary antibody, agarose beads, paramagnetic beads, protein A, streptavidin, sephadex, glass bead, or combinations thereof.

11. The method of claim 1 , wherein the capturing of the antibody-protamine-DNA complex is achieved by further adding a capturing agent, wherein the capturing agent binds to the protamine-specific antibody.

12. The method of claim 11 , wherein the capturing agent comprises a secondary antibody, agarose beads, paramagnetic beads, protein A, streptavidin, sephadex, glass bead, or combinations thereof.

13. The method of claim 11 , wherein the capturing agent is a secondary antibody specific to the protamine-specific antibody.

14. The method of claim 11 , wherein the captured antibody-protamine-DNA complex is washed to remove unbound material and purify the sperm DNA.

15. The method of claim 14 , further comprising incubating the captured antibody-protamine-DNA complex in an ion exchange resin.

16. The method of claim 15 , wherein the captured antibody-protamine-DNA complex is incubated at 95° C. for at least 10 minutes.

17. The method of claim 1 , wherein a reporter moiety is coupled to the protamine-specific antibody and wherein a detection of the reporter moiety indicates the presence of the sperm DNA in the biological sample.

18. The method of claim 17 , wherein the reporter moiety comprises a chromophore moiety, a fluorescent moiety, a phosphorescence moiety, an affinity probe, a magnetic probe, a paramagnetic probe, a metallic probe, or combinations thereof.

19. The method of claim 1 , wherein the detection of the sperm DNA comprises one or more amplification reactions of the sperm DNA to form an amplified DNA.

20. The method of claim 19 , further comprising analyzing the amplified DNA.

21. The method of claim 1 , wherein the biological sample further comprises epithelial cells, somatic cells, blood cells, or combinations thereof.

22. The method of claim 1 , wherein the biological sample is selected from a forensic sample comprising sperm cells.

23. A method of detecting sperm deoxyribonucleic acid (DNA) in a biological sample, comprising:
providing the biological sample comprising at least a sperm cell, a partially lysed sperm cell or a sperm cell lysate, wherein the sperm cell, partially lysed sperm cell or sperm cell lysate comprises a protamine-DNA complex;
contacting a lysis solution to the biological sample to lyse the sperm cell or partially lysed sperm cell, wherein the lysis solution comprises at least one of a reducing agent and a detergent, wherein the protamine-DNA complex remains intact after contacting the lysis solution;
applying a sequestration agent after the sperm cell lysis to the sample comprising the lysed sperm cells, or the partially lysed sperm cells and an excess of the lysis solution to sequester an excess detergent of the excess of the lysis solution;
applying at least a protamine-specific antibody to the lysed sperm cell after the sequestration of the excess detergent, wherein the protamine-specific antibody binds to the protamine-DNA complex of the lysed sperm cell to form an antibody-protamine-DNA complex;
capturing the antibody-protamine-DNA complex by adding a capturing agent; and
detecting the sperm DNA from the captured antibody-protamine-DNA complex by a DNA amplification reaction.

Assignees

• Gen Electric

Inventors

• Gerdes Michael John
• Nelson John Richard
• Spooner Patrick Mccoy
• Lenigk Ralf

Classifications

• C12Q2522/101

  Single or double stranded nucleic acid binding proteins · CPC title

• C12N15/1003

  Extracting or separating nucleic acids from biological samples, e.g. pure separation or isolation methods; Conditions, buffers or apparatuses therefor · CPC title

• G01N33/689

  related to pregnancy or the gonads · CPC title

• C12Q1/6804 Primary

  Nucleic acid analysis using immunogens (immunoassay G01N33/53) · CPC title