Change of elastase and cathepsin G content in polymorphonuclear leukocytes during hemodialysis

Previous studies have demonstrated an increment of polymorphonuclear (PMN) elastase plasma levels during hemodialysis, suggesting release of this proteinase during dialysis treatment. In order to gain further evidence that proteinases are liberated from PMN leukocytes during dialysis both plasma levels of PMN elastase and the content of elastase and cathepsin G in neutrophils were determined during 3 hours of hemodialysis with cellulosic membranes (Cuprophan) in 10 patients. In blood smears, obtained at different times during dialysis, neutrophils were classified into 3 groups according to their proteinase content. Thus, group I neutrophils contained low, group II moderate, and group III leukocytes contained high amounts of both proteinases. With regard to their elastase content, prior to the onset of dialysis, 6% of the circulating PMN leukocytes were classified as fraction I, 58% as fraction II, and 36% as fraction III neutrophils. After 15 minutes of dialysis, at the nadir of leukopenia, all fractions of PMN leukocytes were significantly reduced (fraction I: -9%, fraction II: -60%, and fraction III: -83%) as compared to initial values. 30 minutes into hemodialysis, there was a significant increase in fraction I (+ 78%), whereas fraction II (-28%) and fraction III (-70%) remained diminished. At 180 times of hemodialysis the increment of fraction I neutrophils was even more pronounced (+ 187%), fraction II was also increased (+ 16%), and fraction III neutrophils had almost reached initial values. The cathepsin G content of PMN leukocytes displayed a rather similar pattern during dialysis. As to plasma levels of PMN elastase, there was a steady and significant increase from baseline values of 107.3 +/- 11.5 ng/ml up to 388.1 +/- 51.6 ng/ml after 3 hours of hemodialysis.(ABSTRACT TRUNCATED AT 250 WORDS)