Inhibition of C5a-induced actin polymerization, chemotaxis, and phagocytosis of human polymorphonuclear neutrophils incubated in a glucose-based dialysis solution.
Chemotaxis and phagocytosis are important functions of phagocytic cells, which are closely related to cytoskeletal reorganization. These functions may be abnormal in phagocytes of uremic patients undergoing continuous ambulatory peritoneal dialysis (CAPD). In order to examine whether these abnormalities result from treatment, we studied actin polymerization (AP), as an index of cytoskeletal alterations, chemotaxis, and phagocytosis in polymorphonuclear neutrophils (PMNs) of healthy subjects. Polymorphonuclear neutrophils were exposed to either a hepes buffer or a glucose-based dialysis solution (GBDS) of different pH's (5.2, 7.4) and different glucose concentrations (1.36%, 2.27%, 3.86%). After incubation for 0, 5, or 20 minutes, cells were activated with 10 nmol/L C5a-complement. AP was measured as filamentous (F) actin content by NBD phallacidin staining and FACS analysis. Chemotaxis of PMNs was measured in Boyden chambers. In addition, phagocytosis of zymosan particles was assessed. Prior exposure to GBDS pH 5.2 of each glucose concentration immediately and completely inhibited AP in response to 10 nmol/L C5a-complement, reduced chemotaxis (> 95%), and completely inhibited phagocytosis. The inhibition was pH-dependent, since GBDS pH 7.4 caused less inhibition of these functions. We conclude that glucose-based dialysis solutions are cytotoxic towards neutrophils and completely inhibit their ability to display responses requiring cytoskeletal reorganization.
Dobos
G J
GJ
Department of Nephrology, University Hospital Freiburg, Germany.
Andre
M
M
Böhler
J
J
Norgauer
J
J
Lubrich-Birkner
I
I
Steinhauer
H B
HB
Schollmeyer
P J
PJ
D000199:Actins / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte; D015936:Complement C5a / Q000502:physiology*; D015314:Dialysis Solutions / Q000737:chemistry / Q000633:toxicity*; D005947:Glucose / Q000633:toxicity*; D006801:Humans; D066298:In Vitro Techniques; D009504:Neutrophils / Q000502:physiology; D010531:Peritoneal Dialysis, Continuous Ambulatory; D010587:Phagocytosis; D011108:Polymers
D000199:Actins; D015314:Dialysis Solutions; D011108:Polymers; D015936:Complement C5a; D005947:Glucose