Diagnostic markers for platelet function and methods of use
Disclosed herein are biomarkers of platelet function and methods for assessing platelet function in response to antiplatelet therapy and for determining a prognosis, diagnosis, or risk identification in a patient by detecting at least one biomarker of platelet function in the patient as well as determining amounts thereof. The biomarkers may be used to identify a patient as a candidate for treatment with an antiplatelet agent and to monitor and adjust antiplatelet therapy in a patient.
1. A method for determining risk of death and/or myocardial infarction in a human patient, the method comprising:
(a) determining the gene expression level of at least one biomarker of platelet function selected from the group consisting of FSTL1, CTDSPL, TREML1, SPARC, ITGA2B, CMTM5, SLC24A3, CLU, CPNE5, CLEC1B, SELP, IGF2BP3, SH3BGRL2, PROS1, ALOX12, ITGB3, PPBP, MGLL, THBS1, MYL9, PF4, GP1BB, TGFB1I1, PCSK6, CALD1, PDE5A, TTC7B, PARVB, TUBB1, GNG11, PRKAR2B, PBX1, ENDOD1, FRMD3, ELOVL7, CLEC4D, C12ORF39, PCGF5, HIST1H3H, HIST1H2BG, LGALSL, HIST1H2AG, ARHGAP18, RAB4A, TPM1, and TRBV27 in a blood sample from the human patient, wherein the gene expression level is determined by measuring the mRNA level;
(b) calculating a normalized expression level of each biomarker in the blood sample from the human patient;
(c) calculating a patient factor score that is greater than a reference factor score, by entering the normalized expression level of each biomarker in the blood sample from the human patient into a model;
(d) identifying the human patient as being at risk of death and/or myocardial infarction based on the patient factor score calculated in step (c); and
(e) administering an antiplatelet agent to the human patient identified in step (d) as being at risk of death and/or myocardial infarction.
2. The method of claim 1 , wherein the normalized expression level of each biomarker in the blood sample from the human patient is determined by subtracting the geometric mean of the expression levels of 3 or 4 genes selected from PPIB, TRAP1, GAPDH, and ACTB in the blood sample from the human patient, from the determined gene expression level of each biomarker in the blood sample from the human patient.
3. The method of claim 1 , wherein the gene expression level of at least five biomarkers of platelet function is determined in step (a).
4. The method of claim 1 , wherein the gene expression level of each biomarker of platelet function selected from FSTL1, CTDSPL, TREML1, SPARC, ITGA2B, CMTM5, SLC24A3, CLU, CPNE5, SELP, IGF2BP3, SH3BGRL2, ALOX12, ITGB3, PPBP, THBS1, MYL9, PF4, GP1BB, TGFB1I1, PCSK6, CALD1, PDE5A, TTC7B, TUBB1, GNG11, PRKAR2B, PBX1, FRMD3, and ELOVL7 are determined in step (a).
5. The method of claim 1 , wherein the reference factor score of step (c) is determined by:
(i) determining the gene expression level of at least one biomarker of platelet function selected from the group consisting of FSTL1, CTDSPL, TREML1, SPARC, ITGA2B, CMTM5, SLC24A3, CLU, CPNE5, CLEC1B, SELP, IGF2BP3, SH3BGRL2, PROS1, ALOX12, ITGB3, PPBP, MGLL, THBS1, MYL9, PF4, GP1BB, TGFB1I1, PCSK6, CALD1, PDE5A, TTC7B, PARVB, TUBB1, GNG11, PRKAR2B, PBX1, ENDOD1, FRMD3, ELOVL7, CLEC4D, C12ORF39, PCGF5, HIST1H3H, HIST1H2BG, LGALSL, HIST1H2AG, ARHGAP18, RAB4A, TPM1, and TRBV27 in a plurality of reference blood samples, each reference blood sample from a different reference subject, wherein the gene expression level is determined by measuring the mRNA level;
(ii) calculating a normalized expression level of each biomarker in each reference blood sample; and
(iii) calculating a reference factor score by entering the normalized expression level of each biomarker in each reference blood sample into a model.
6. The method of claim 5 , wherein the normalized expression level of each biomarker in each reference blood sample is determined by subtracting the geometric mean of the expression levels of 3 or 4 genes selected from PPIB, TRAP1, GAPDH, and ACTB in each reference blood sample, from the determined gene expression level of each biomarker in each reference blood sample.
7. The method of claim 5 , wherein the reference subjects are healthy subjects, or subjects without cardiovascular disease, or subjects having cardiovascular disease but who have not suffered death or myocardial infarction, or a combination thereof.
8. The method of claim 5 , the method further comprising validating the reference factor score against a known dataset.
9. The method of claim 1 , wherein the at least one biomarker of platelet function is selected from the group consisting of FSTL1, TREML1, SPARC, ITGA2B, CMTM5, CLU, CPNE5, CLEC1B, SELP, IGF2BP3, SH3BGRL2, PROS1, ITGB3, PPBP, MGLL, THBS1, MYL9, GP1BB, TGFB1I1, TTC7B, PARVB, PRKAR2B, PBX1, ENDOD1, FRMD3, ELOVL7, CLEC4D, C12ORF39, PCGF5, HIST1H3H, HIST1H2BG, LGALSL, HIST1H2AG, RAB4A, TPM1, and TRBV27 in step (a).