Cytokines in tear fluid of patients with ocular graft-versus-host disease after allogeneic stem cell transplantation

Purpose: To investigate the profile of cytokines in tear fluid of patients after allogeneic stem cell transplantation (allo-SCT) and determine their relation to the presence and manifestations of ocular graft-versus-host disease (GvHD). Methods: In this cross sectional study tear fluid was collected in 34 consecutive adult patients that previously underwent allo-SCT (16 with ocular GvHD and 18 without) and 16 age- and gender-matched healthy controls using the Schirmer test under local anesthesia. Tear fluid was analyzed by multiplex immunoassay for the presence of interleukin (IL)-2, IL-4, IL-6, IL-10, IL-17, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. Levels of measured cytokines were correlated with the find Results: The levels of IL-6 and IFN-gamma in tear fluid in ocular GvHD patients were significantly elevated in comparison to patients without ocular GvHD and healthy controls (p<0.005 for each) The levels of IFN-gamma correlated with the Schirmer score (r=-0.48, p<0.0001) and tear break up time (TBUT; r=-0.38, p=0.03). Tear IL-6 levels correlated with complaints of dry eyes (r=0.39, p=0.02), tear production (r=-0.59, p