Altered expression of T cell Immunoglobulin-Mucin (Tim) molecules in peripheral blood mononuclear cells in aplastic anemia

To evaluate the balance between T-cell immunoglobulin and mucin domain (Tim) molecules(Tim)-1 and Tim-3 in patients with aplastic anemia (AA), plasma IFN-γ and IL-4 levels were measured in patients with active AA (n = 41), AA in remission (n = 29) and in healthy subjects (n = 40) by enzyme linked immunosorbent assay (ELISA). Using real-time quantitative polymerase chain reaction (RT-PCR), the mRNA expression of IFN-γ, IL-4, Tim-1 and Tim-3 were studied in all subjects. The results showed that the expression of Tim-3 in newly diagnosed patients was significantly deceased, compared with the controls. Meanwhile, Tim-1 mRNA expression in the active AA group was not significantly reduced, which resulted in a declined ratio of Tim-3/Tim-1 in patients with active disease. During the remission stages, the levels of these transcription factors were comparable with those observed in the healthy controls. These findings are the first data on the expression of the Tim-1 and Tim-3 molecules in AA. The reduced levels of Tim-3/Tim-1 in PBMCs during the active stages of disease suggest that they may play a possible role in the pathogenesis and course of AA.