Gap in scientific knowledge: Researchers have shown that proinflammatory cytokines are elevated in tears of humans with dry eye; many of these may be secreted by immune cells. They found in preliminary flow cytometric studies that CD4+ T cells, CD19+ B cells, CD14+ monocytes, CD1c dendritic cells can be quantified using minimally invasive impression membranes (Eyeprim)[31]. The full subset of immune cells activated in the ocular surface in dry eye, and in various rheumatological conditions, is not known. The proportions of these cells in different severity of dry eye and different systemic activity of autoimmune disease have not been evaluated. Furthermore, it is uncertain whether the integrity of cornea innervation is also a determinant of tear function in patients with autoimmune systemic disease.