Processes for the diagnosis, prognosis and monitoring of the progression of chronic lymphoid leukaemia (CLL) and/or of systemic lupus erythematosus (SLE) using membrane STIM 1

A method for determining if a human patient suffering from systemic lupus erythematosus (SLE) is at risk for disease progression, said method comprising:

• (a) providing a sample comprising B cells from the patient;
• (b) measuring the level of expression of stromal interaction molecule 1 (STIM1) comprising SEQ ID NO:
• 1 at the plasma membrane surface of the B cells of the sample;
• (c) comparing the measured level of expression of STIM1 to the level of expression of STIM1 expressed on the surface of B cells of a human subject not suffering from SLE;
• and
• (d) determining that the patient is at risk for disease progression if the measured level of expression of STIM1 is greater than the level of expression of STIM1 expressed on the surface of B cells of a human subject not suffering from SLE.