Cystic Fibrosis: Lysosomal and Mitochondrial Enzyme Activities of Lymphoid Cell Lines

Abstract

ExtractSeven lysosomal enzymes and three mitochondrial enzymes were studied in cultured lymphoid cells from four patients with cystic fibrosis, three heterozygotes, one borderline patient, and six healthy controls. The lysosomes and mitochondria were isolated by differential and density gradient centrifugation. The activity of a-glucosidase, which is a lysosomal enzyme degrading glycogen, showed a marked increase in activity in the lysosomes of cultured lymphoid cells obtained from patients with cystic fi brosis as compared with the healthy controls. Two substrates were used for measuring the activity of this enzyme, the synthetic jfr-nitrophenyl-a-glucoside (p-NP-aglucoside), and the physiologic substrate glycogen. The values obtained with/>-NP-aglucoside were 32.6 (SD ± 8.6) and 13.8 (SD ± 12.2) ^moles/g lysosomal protein/hr and with glycogen 543.5 (SD ± 163.3) and 188.6 (SD ± 156.3) yumoles/g lysosomal protein/hr for patients with cystic fibrosis and controls, respectively. The values of a-glucosidase in the heterozygotes were also elevated, 17.2 (SD ± 5.5), controls 13.8 (SD ± 12.2) using/)-NP-a-glucoside as substrate. When glycogen was used as substrate, the values were 226.7 (SD =1= 85.3) in the heterozygote and 188.6 (SD ± 156.3) ^moles/g lysosomal protein/hr in the control.

Serum Neutral α-D-Glucosidase from Patients with Cystic Fibrosis and Chronic Pulmonary Disease

“…For each parameter, the day 2 range was lower, the slope of the day 2 versus day 1 regression line was significantly less than 1 ( p < 0.01) and the y-intercept was significantly greater than zero ( p < Two-channel recordings of ECG and thoracic impedence (pneumograms) are commonly performed in infants with symptomatic apnea and in asymptomatic infants considered to be at increased risk for SIDS. Based primarily on single 24-h recordings, Kelly and coworkers (3,4) documented significantly greater periodic breathing in A01 infants and in subsequent siblings compared to control infants. In earlier reports, we confirmed the presence of pneumogram abnormalities in A01 compared to control infants (2), and documented improvement in these abnormalities with theophylline (1).…”

“…Numerous studies have been done on lysosomal glycosidases but few consistent findings have been reported. Among the most reproducible of the findings on glycosidases is the significant elevation of a-D-glucosidase activity in CF tissues (2)(3)(4)(5)(6)(7). In a previous study we confirmed the fact that neutral a-D-glucosidase activity is significantly elevated in CF sera (2).…”

Lysozyme Activity in Cystic Fibrosis

“…In 1970 Bartman et al (2), with ultrastructure studies, observed an increase in the number patients. ~l s o , the activity of a-glucosidase, a lysosomal enzyme that degrades glycogen, has been found to be increased in the lysosomes of cultured lymphoid cells obtained from patients with cystic fibrosis as compared with normal controls (1). More recent studies with skin fibroblasts suggest that leakage from intracellular to extracellular sites occurs with multiple lysosomal enzymes (15).…”

Studies in Meconium in Cystic Fibrosis: the Activities of alpha-<i>D</i>-Mannosidase, beta-Glucuronidase, beta-<i>D</i>-Fucosidase Acid and Alkaline Phosphatase

“…The determination of 0-glucuronidase (EC 3.2.1.31) and acid phosphatase (EC 3.1.30) were performed as previously described (5). Alkaline phosphatase (EC 3.1.31) was measured using the method of Unhardt and Walter (24) modified for microdetermination.…”