Alterations in soluble and leukocyte surface L-selectin (CD 62L) in hemodialysis patients.

Hemodialysis (HD) patients can develop acute reactions during treatment as well as increased long-term susceptibility to infections and malignancy. Leukocyte-membrane interactions may contribute to these processes. The effects of a single HD session on iselectin, a leukocyte adhesion molecule for endothehum, were examined. Serum levels of soluble i-selectin were measured in 23 patients by enzyme-linked immunosorbent assay before and after a 3-h dialysis session. There was a statistically significant increase in soluble L-selectin from 1.36 ± 0. 1 2 (SE) to 1 .57 ± 0.18 .tg/mL (P < 0.01). An increase in shed L-selectin was observed for the “venous” compared with the “arterial” port of the dialyser (P < 0.01) 15 mm into HD. Soluble L-selectin levels were found to remain increased at 3 h after treatment. Leukocyte-bound iselectin and CD1 1b was examined by the use of flow cytometry. Neutrophil i-selectin decreased to 69 ± 7% at 15 mm (P < 0.01) and then rebounded to 98 ± 7% at 180 mm. Monocyte and lymphocyte i-selectin did not decrease. Because L-selectin is important for leukocyte attachment to endothelium at sites of inflammation, alterations of shed L-selectin and cell-surface L-selectin levels may play a role in the immunologic consequences of HD treatment.