Mass spectral tissue analysis
The invention generally relates to mass spectral analysis. In certain embodiments, methods of the invention involve analyzing a lipid containing sample using a mass spectrometry technique, in which the technique utilizes a liquid phase that does not destroy native tissue morphology during analysis. Due to the use of a liquid phase that does not destroy native tissue morphology during analysis, a subsequent staining technique can be performed on the tissue sample and an overlaid image can be produced of a mass spectral image and a staining image.
1. A method for assessing a tissue sample for presence of cancerous cells, the method comprising:
receiving mass spectral data of a tissue sample produced in part via use of a solvent that when in contact with the tissue sample does not destroy native morphology of the tissue sample;
producing a mass spectral image of the tissue sample based on the mass spectral data;
receiving histochemical data of the tissue sample;
producing an optical image of the tissue sample from the histochemical data;
overlaying the mass spectral image of the tissue sample with the optical image of the tissue sample to produce an overlaid image; and
assessing the overlaid image for presence of cancerous cells.
2. The method according to claim 1 , wherein assessing comprises determining a distribution of one or more compounds in the tissue sample based on an analysis of the overlaid image.
3. The method according to claim 1 , wherein the mass spectral data is produced using a desorption electrospray ionization (DESI) technique that comprises directing a liquid phase that does not destroy native tissue morphology from a DESI probe onto the tissue sample to thereby desorb one or more compounds from the tissue sample that are analyzed by a mass spectrometer.
4. The method of claim 3 , wherein the liquid phase is the solvent and the solvent comprises dimethylformamide (DMF), acetonitrile (ACN), or tetrahydrofuran (THF).
5. The method according to claim 4 , wherein the liquid phase comprises at least one other component.
6. The method according to claim 5 , wherein the at least one other component is selected from the group consisting of ethanol (EtOH), water (H 2 O), acetonitrile (ACN), and a combination thereof.
7. The method according to claim 3 , wherein the liquid phase is selected from the group consisting of: acetonitrile (ACN):ethanol (EtOH); methanol (MeOH):chloroform (CHCl 3 ); and acetonitrile (ACN):chloroform (CHCl 3 ).
8. The method according to claim 1 , wherein the histochemical data is produced by H&E staining.
9. The method according to claim 3 , wherein the one or more compounds comprises one or more lipids.
10. The method according to claim 2 , further comprising grading the cancerous cells based on the distribution of the one or more compounds in the tissue sample.
11. The method according to claim 10 , wherein the cancerous cells are indicative of brain or bladder cancer.
12. A method for assessing a tissue sample for presence of cancerous cells, the method comprising:
receiving mass spectral data of a tissue sample comprising a cancerous section produced in part via use of a solvent that when in contact with the tissue sample does not destroy native morphology of the tissue sample;
producing a mass spectral image of the tissue sample comprising the cancerous section based on the mass spectral data;
receiving histochemical data of the tissue sample comprising the cancerous section;
producing an optical image of the tissue sample comprising the cancerous section from the histochemical data;
overlaying the mass spectral image of the tissue sample comprising the cancerous section with the optical image of the tissue sample comprising the cancerous section to produce an overlaid image;
identifying the cancerous section within the overlaid image; and
assessing the overlaid image to determine a grade of the cancerous section.
13. The method according to claim 12 , wherein the mass spectral data is produced using a desorption electrospray ionization (DESI) technique operated in imaging mode.
14. The method according to claim 13 , wherein the mass spectral data is produced using a DESI technique that comprises directing a liquid phase that does not destroy native tissue morphology from a DESI probe onto the tissue sample to thereby desorb one or more compounds from the tissue sample that are analyzed by a mass spectrometer.
15. The method of claim 14 , wherein the liquid phase is the solvent and the solvent comprises dimethylformamide (DMF), acetonitrile (ACN), or tetrahydrofuran (THF).
16. The method according to claim 15 , wherein the liquid phase comprises at least one other component.
17. The method according to claim 16 , wherein the at least one other component is selected from the group consisting of ethanol (EtOH), water (H 2 O), acetonitrile (ACN), and a combination thereof.
18. The method according to claim 14 , wherein the liquid phase is selected from the group consisting of: acetonitrile (ACN):ethanol (EtOH); methanol (MeOH):chloroform (CHCl 3 ); and acetonitrile (ACN):chloroform (CHCl 3 ).
19. The method according to claim 12 , wherein the histochemical data is produced by H&E staining.
20. The method according to claim 14 , wherein the one or more compounds comprises one or more lipids.