Cystatin C and cathepsin B in CSF from patients with inflammatory neurologic diseases.

BACKGROUND: In CSF, proteolytic enzymes are believed to have crucial roles in the initiation and progression of inflammatory neurologic diseases (IND). Cystatin C, a major cysteine protease inhibitor in CSF, is tightly bound to cathepsin B and H. OBJECTIVE: To determine if cystatin C is involved in the disease process of IND, the authors measured the cystatin C concentration by ELISA method and cathepsin B and H activities in the CSF of patients with acute IND. METHODS: Cystatin C concentration and cathepsin B and H activities were measured in CSF samples taken from patients during the acute phase of their disease. Subjects studied were 8 patients with Guillain-Barré syndrome (GBS), 5 with chronic inflammatory demyelinating polyneuropathy (CIDP), 12 with MS, 16 with aseptic meningitis, 15 with neurodegenerative diseases as disease controls, and 35 healthy controls. RESULTS: A significant decrease in CSF cystatin C level was seen in the patients with GBS, CIDP, and MS compared to the control subjects. High cathepsin B activity, but not cathepsin H activity, was also observed in the patients with GBS, CIDP, and MS. CONCLUSION: Cystatin C levels in CSF measured by ELISA may help the physician recognize GBS, CIDP, and MS. Decreased levels of cystatin C may be related to the high levels of cathepsin B activity seen in the CSF of patients with GBS, CIDP, and MS.

Secretion of laminin alpha 2 chain in cerebrospinal fluid.

The absence of laminin alpha 2 chain causes muscle cell degeneration and peripheral dysmyelination in congenital muscular dystrophy patients and dy mice, suggesting its role in the maintenance of sarcolemmal architecture and peripheral myelinogenesis. Here we demonstrate the secretion of laminin alpha 2 chain in cerebrospinal fluid (CSF). Laminin alpha 2 chain was detected as a minor component of the total CSF proteins or glycoproteins. Laminin alpha 2 chain was localized in the cytoplasm of epithelial cells of choroid plexus, suggesting active secretion. Our results suggest that immunochemical analysis of CSF laminin alpha 2 chain could be useful as an aid for the diagnosis of congenital muscular dystrophy.

Cerebrospinal fluid proteins in muscular dystrophy patients.

We analyzed and quantified the microcomponents of protein fractions in the cerebrospinal fluid of patients with various types of muscular dystrophy. The degenerative pattern is characterized by an increase in the prealbumin fraction and a decrease in the gamma-globulin fraction as shown in the Duchenne and congenital muscular dystrophy. The increase in CSF IgG, gamma-globulin fraction, and myelin basic protein is shown in the myotonic dystrophy. In addition to the lowness of IQ, and the abnormality of EEG and brain CT, abnormal CSF proteins obviously suggest the presence of CNS involvement in muscular dystrophy.

[Degenerative type profile of cerebrospinal fluid electrophoresis in myopathies (author's transl)]. / Profil de type dégénératif de l'électrophorèse du liquide céphalo-rachidien au cours des myopathies.

Normal CSF proteins electrophoresis has been compared to 74 cases of progressive muscular dystrophies : 29 cases of Duchenne type, 3 cases of Becker type, 8 cases of limb girdle dystrophies, and 34 cases of severe muscular dystrophies with autosomal recessive heredity (Duchenne like). A degenerative profile type of electrophoresis was frequent, and it is characterized by a decrease of the total proteins and an increase of pre-albumins.

Isoelectric focusing and electrophoresis of cerebrospinal fluid proteins in muscular dystrophies and spinal muscular atrophies.

In the very few previous investigations of the CSF-proteins in muscular dystrophies the results have generally been reported as normal. In spinal muscular atrophies a barrier-damage pattern of CSF-proteins has been found in amyotrophic lateral sclerosis (ALS). In the present investigation the CSF-proteins were examined by isoelectric focusing and quantitative paper electrophoresis in 13 patients with muscular dystrophies and in 11 patients with spinal muscular atrophies. On isoelectric focusing, CSF-protein abnormalities were found in 85% of the cases with muscular dystrophies and in all patients with spinal muscular atrophies. Differences in the CSF-protein patterns were observed within the group of muscular dystrophies and between these and the cases of spinal muscular atrophies. In ALS and in myotonic dystrophy, abnormal CSF-protein fractions occurred mainly in the alkaline pH-range, while in limb-girdle dystrophy and the patient with facioscapulohumeral dystrophy, aberrant fractions appeared mainly in the acidic region. CSF-protein abnormalities were found in both the alkaline fractions (HAFs) with pI 9.2-9.6 and a fraction with PI 7.1 were found in half of the patients with myotonic dystrophy. The CSF electrophoresis in myotonic dystrophy showed increased levels of beta1-globulin in all cases examined. Signs of barrier-damage were commonly encountered in ALS in contrast to the muscular dystrophies, except for myotonic dystrophy. The results are discussed in terms of possible diagnostic value and with regard to pathogenetic significance, particularly in relation to the current hypothesis of a neural involvement in muscular disorders.