Impact of hemodialysis membrane and permeability on neutrophil transmigration in vitro.
OBJECTIVE
The impact of dialysis membrane permeability on neutrophil transmigration properties in vitro was examined in the present study. This issue has not been fully scrutinized before.


METHODS
We studied the capacity of neutrophils collected from a group of dialysis patients randomly treated with cuprophan, low- or high-flux polysulfone, to transmigrate in vitro through a membrane covered with fibronectin (a main constituent of the endothelial basement membrane). The hemodialysis-induced quantitative changes in expression of adhesion molecules were examined in parallel.


RESULTS
At the end of dialysis, neutrophils collected from patients treated with high-flux polysulfone dialyzers had a significantly higher transmigration index than neutrophils from patients treated with low-flux polysulfone membrane (p < 0.01) or cuprophan membrane (p < 0.01), and approached the level of transmigration observed in neutrophils collected from healthy controls. In the groups treated with low-flux polysulfone and cuprophan dialyzers, the transmigration capacity was significantly lower (p < 0.02) compared to neutrophils from healthy subjects. We also noted that differences between low- and high-flux polysulfone dialysis, in the context of transmigration properties, were not mirrored by changes in adhesion phenotype, which strengthens the view that there is no strict relationship between these two features.


CONCLUSIONS
The study demonstrates that high-flux polysulfone dialysis, as opposed to low-flux polysulfone and cuprophan treatment, improves the transmigration properties of circulating neutrophils, despite similar effects on adhesion molecule phenotypes. A plausible mechanism is that potentially toxic middle range molecules that inhibit neutrophil migration are more efficiently eliminated during high-flux polysulfone dialysis, but this explanation requires further support.
Moshfegh
Ali
A
Department of Medicine, Division of Clinical Immunology and Allergy, Karolinska Institutet, and Karolinska Hospital, Stockholm, Sweden. ali.moshfegh@ks.se
Jacobson
Stefan H
SH
Halldén
Gunilla
G
Thylén
Pia
P
Lundahl
Joachim
J
D039481:CD11b Antigen / Q000032:analysis; D002465:Cell Movement; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D019041:L-Selectin / Q000032:analysis; D018655:Lymphocyte Count; D008297:Male; D008567:Membranes, Artificial; D009504:Neutrophils / Q000166:cytology* / Q000276:immunology; D010539:Permeability; D006435:Renal Dialysis / Q000295:instrumentation*
D039481:CD11b Antigen; D008567:Membranes, Artificial; D019041:L-Selectin