Cell preserving solution
The disclosure relates to devices, solutions and methods for collecting and processing samples of bodily fluids containing cells (as well as embodiments for the collection, and processing and/or analysis of other fluids including toxic and/or hazardous substances/fluids). In addition, the disclosure relates generally to function genomic studies and to the isolation and preservation of cells from saliva and other bodily fluids (e.g., urine), for cellular analysis. With respect to devices for collection of bodily fluids, some embodiments include two mating bodies, a cap and a tube (for example), where, in some embodiments, the cap includes a closed interior space for holding a sample preservative solution and mates with the tube to constitute the (closed) sample collection device. Upon mating, the preservation solution flows into the closed interior space to preserve cells in the bodily fluid. The tube is configured to receive a donor sample of bodily fluid (e.g., saliva, urine), which can then be subjected to processing to extract a plurality of cells. The plurality of cells can be further processed to isolate one and/or another cell type therefrom. The plurality of cells, as well as the isolated cell type(s), can be analyzed for functional genomic and epigenetic studies, as well as biomarker discovery.
1. A method for preserving and analyzing cells in saliva, the method comprising:
(a) contacting saliva with a solution, wherein the solution comprises paraformaldehyde, sodium azide, and fetal bovine serum, buffered at a pH from about 6.4 to about 8.4;
(b) mixing the saliva and the solution to form a mixture;
(c) storing the mixture at room temperature, wherein the cells retain their antigenicity and cellular architecture during said storage;
(d) separating the cells into cell types; and
(e) subsequently subjecting the separated cells to downstream epigenetic analysis,
wherein the cells are preserved for downstream epigenetic analysis.
2. The method of claim 1 , wherein the solution further comprises at least one antimicrobial agent.
3. The method of claim 1 , wherein paraformaldehyde is present in the solution at a concentration of about 1% (v/v).
4. The method of claim 2 , wherein the antimicrobial agent is selected from the group consisting of antibacterial and antifungal antibiotics.
5. The method of claim 1 , wherein the solution is buffered at a pH of from about 7.2 to about 7.6.
6. The method of claim 1 , wherein the buffer is selected from the group consisting of: barbital, trisphosphate, citrate, cacodylate, other non—phosphate buffers, and any combination of the foregoing.
7. The method of claim 1 , wherein the buffer is a phosphate buffer.
8. The method of claim 1 , wherein the solution comprises about 1% (v/v) of fetal bovine serum.
9. The method of claim 1 , wherein the solution comprises about 1% (v/v) of paraformaldehyde, about 1% (v/v) of fetal bovine serum, and about 0.01% (w/v) of sodium azide.
10. The method of claim 1 , wherein the saliva is in contact with the solution at a ratio of 1:1 (v/v).
11. The method of claim 1 , wherein the saliva is in contact with the solution at room temperature for at least one week.
12. The method of claim 1 , wherein the method crosslinks histones to the DNA in the saliva.
13. A method for preserving and analyzing cells in saliva, the method comprising:
(a) contacting saliva with a solution consisting essentially of paraformaldehyde, sodium azide, fetal bovine serum, a buffer, and an optional antimicrobial agent, wherein the solution has a pH from about 6.4 to about 8.4;
(b) mixing the saliva and the solution to form a homogeneous mixture;
(c) storing the mixture at room temperature, wherein the cells retain their antigenicity and cellular architecture during said storage;
(d) separating the cells into cell types; and
(e) subsequently subjecting the separated cells to downstream epigenetic analysis,
wherein the cells are preserved for downstream epigenetic analysis.