Compositions and methods for sjögren's syndrome

1. A method of identifying a subject as having Sjögren's syndrome (SS), or as having an increased risk of developing SS, comprising:

a) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject;

b) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject;

c) measuring the levels of long interspersed nuclear elements (LINEs) and the protein encoded by LINE1 (ORF1(p40)) in a saliva sample from the subject;

d) comparing the mRNA transcript levels of (a), the DNA methylation status of (b) and the levels of LINEs and the protein encoded by LINE1 of (c) with a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 correlated with SS, DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 correlated with SS and levels of LINEs and the protein encoded by LINE1 correlated with SS, wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 of the subject having similarity with mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 correlated with SS identifies the subject as having SS or as having an increased risk of developing SS; and

e) treating the subject for SS.

2. A method of identifying a subject having SS as having an increased likelihood of a poor prognosis, comprising:

a) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject;

b) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject;

c) determining the levels of long interspersed nuclear elements (LINEs) and the protein encoded by LINE1 in a saliva sample from the subject;

d) comparing the level of mRNA transcripts of (a), the DNA methylation status of (b) and the levels of LINEs and protein encoded by LINE1 of (c) with mRNA transcript levels of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 correlated with severe or advanced SS, the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 correlated with severe or advanced SS, and the levels of LINEs and the protein encoded by LINE1 correlated with severe or advanced SS,

wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINEs of the subject having similarity with the mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 correlated with severe or advanced SS identifies the subject having SS as having an increased likelihood of a poor prognosis; and

e) treating the subject for severe or advanced SS.

3. A method of monitoring a subject's response to treatment for SS, comprising:

a) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject prior to treatment of the subject for SS;

b) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject prior to treatment of the subject for SS;

c) determining levels of long interspersed nuclear elements (LINEs) and protein encoded by LINE1 in a saliva sample from the subject prior to treatment of the subject for SS;

d) initiating treatment of the subject for SS;

e) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for SS;

f) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, TIMP1 and TLR7 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for SS;

g) determining levels of long interspersed nuclear elements (LINEs) and protein encoded by LINE1 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for SS;

h) comparing the mRNA transcript levels of (a) and (e), the DNA methylation status of (b) and (f) and the levels of LINEs and the protein encoded by LINE1 of (c) and (g), wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 determined after initiation of treatment for SS having less similarity with the mRNA transcript levels, DNA methylation status and levels of LINES and the protein encoded by LINE1 correlated with SS identifies the subject as having a positive response to the treatment and wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 determined after initiation of treatment for SS having no change or more similarity with mRNA transcript levels, DNA methylation status and levels of LINES and the protein encoded by LINE1 correlated with SS identifies the subject as having no response or a negative response to treatment; and

i) continuing treatment and/or initiating a modified treatment and/or a different treatment for SS of the subject that has no response or a negative response to treatment and discontinuing or reducing treatment for SS of the subject that has a positive response to treatment.

4. A method of monitoring a subject's response to treatment for severe or advanced SS, comprising:

a) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject prior to treatment of the subject for severe or advanced SS;

b) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject prior to treatment of the subject for severe or advanced SS;

c) determining levels of long interspersed nuclear elements (LINEs) and protein encoded by LINE1 in a saliva sample from the subject prior to treatment of the subject for severe or advanced SS;

d) initiating treatment of the subject for severe or advanced SS;

e) measuring a level of messenger RNA (mRNA) transcripts for the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, MMP9 and TLR7 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for severe or advanced SS;

f) determining the DNA methylation status of the genes ETS1, LEF1, TIMP1, CHEK1, CXCL10, TIMP1 and TLR7 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for severe or advanced SS;

g) determining levels of long interspersed nuclear elements (LINEs) and protein encoded by LINE1 in a saliva sample from the subject at one or more time points after initiation of treatment of the subject for severe or advanced SS;

h) comparing the mRNA transcript levels of (a) and (e), the DNA methylation status of (b) and (f) and the levels of LINEs and the protein encoded by LINE1 of (c) and (g), wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 determined after initiation of treatment for severe or advanced SS having less similarity with the mRNA transcript levels, DNA methylation status and levels of LINES and the protein encoded by LINE1 correlated with severe or advanced SS identifies the subject as having a positive response to the treatment and wherein mRNA transcript levels, DNA methylation status and levels of LINEs and the protein encoded by LINE1 determined after initiation of treatment for severe or advanced SS having no change or more similarity with mRNA transcript levels, DNA methylation status and levels of LINES and the protein encoded by LINE1 correlated with severe or advanced SS identifies the subject as having no response or a negative response to the treatment; and

i) continuing treatment and/or initiating a modified treatment and/or a different treatment for SS of the subject that has no response or a negative response to treatment and discontinuing or reducing treatment for SS of the subject that has a positive response to treatment.