[Regulatory T cells in the treatment of autoimmune myositis in mice: efficacy and mechanism].

OBJECTIVE: To investigate effect of CD4(+) CD25(+) Foxp3(+) Tregs in the treatment of autoimmune myositis (EAM) in mice and explore the possible mechanisms. METHODS: Mouse models of EAM were divided randomly into model group and treatment group, and the latter received infusion of CD4(+) CD25(+) Foxp3(+) Tregs separated from normal mouse spleen by magnetic activated cell sorting. The changes of muscle pathology was observed, and the expression of PD-1 and CTLA-4 in spleen CD4(+) CD25(+) Foxp3(+) Tregs was analyzed using flow cytometry; peripheral blood IL-10 and TGF-ß levels were tested using double antibody sandwich ELISA. RESULTS: Compare with the model group, the mice in the treatment group showed significantly reduced muscular inflammatory cell infiltration, increased blood levels of IL-10 and TGF-ß (P<0.05), and increased expression of PD-1 and CTLA-4 in spleen CD4(+) CD25(+) Foxp3(+) Tregs (P<0.05). CONCLUSION: CD4(+) CD25(+) Foxp3(+) Tregs reinfusion produces therapeutic effect in mice with EAM by increasing peripheral blood IL-10 and TGF-ß levels and PD-1 and CTLA-4 expressions in spleen CD4(+) CD25(+) Foxp3(+) Tregs.

Clinical and pathological features of patients with nemaline myopathy.

Nemaline myopathy (NM) is a rare congenital myopathy of great heterogeneity, characterized by the presence of rods in the cytoplasm of muscle fibers. This study aimed to summarize and analyze retrospectively the clinicopathological features of 28 patients with NM. Among the 28 patients, 15 were classified as of the typical congenital type, manifested as lower- or four-limb weakness as the first symptom and slowly progressive course. Six patients were classified as of childhood onset type, with lower-limb weakness and progressive course. Seven patients were classified as of the adult onset type, with rapidly progressive course and obvious muscle atrophy. Patient's 1, 16 and 23 had rapid clinical progression. On follow up, the three patients showed respiratory failure. Limb weakness in all patients was proximal­dominant. Hypotonia was observed in most patients. High arched feet were also observed as dysmorfic features. In all patients, the creatine kinase (CK) level was normal or mildly elevated, and electromyography revealed myogenic changes. Nemaline bodies were observed under a light microscope in more than half of the patients' muscle fibers, and especially in type I fibers. All patients showed fiber type I predominance and atrophy. Modified Gömöri trichrome staining showed characteristic purple­colored rods. Muscle electron microscopy revealed the presence of high electron­dense nemaline bodies around the nucleus, and of a disorganized myofibrillar apparatus, with broken myofilaments and irregular myofibrils and Z lines. The 28 patients with NM shared a number of clinical features, such as proximal limb weakness, reduced deep tendon reflex and dysmorfic features. Differences were also observed between the three types of patients, with regards to course progression, disease severity and respiratory failure. In conclusion, patients with NM showed great clinical heterogeneity. The diagnosis of NM was mainly based on the muscle biopsy.

Electrophysiological characteristics of polyneuropathy in POEMS syndrome: comparison with CIDP.

OBJECTIVE: The purpose of this study was to evaluate the electrophysiological characteristics of polyneuropathy in POEMS syndrome. METHODS: A total 46 patients with POEMS syndrome and 46 patients with chronic inflammatory demyelinating polyneuropathy (CIDP) were included in this study. Six nerve conduction parameters including (1) motor conduction velocity, distal compound muscle action potential; (2) conduction block and temporal dispersion; (3) motor distal latency; (4) F wave; and (5) sensory conduction velocity were reviewed for the subjects in both POEMS and CIDP groups. RESULTS: The frequency of nerve unresponsiveness in the lower limbs of the POEMS group (motor responses were absent in 37.7% and sensory was absent in 41.7% of the patients) was higher than that of the CIDP group (motor responses were absent in 18.4% and sensory was absent in 24.4% of the patients). The peroneal motor conduction velocity was slowed, compound muscle action potential was lower, and distal latency was longer in POEMS groups than those in CIDP group. The percentage of prolonged distal compound muscle action potential duration, conduction velocities, distal latencies, and the absent F waves compatible with demyelination were significantly different between the two groups. Abnormal temporal dispersion was rarely seen, and conduction block was not observed in the patients with POEMS syndrome. CONCLUSIONS: The findings suggest that peroneal nerves are more severely involved, temporal dispersion of the distal compound muscle action potential and conduction block are less common, and there are less alterations of conduction (less demyelination) as evidenced by more normal distal latencies, conduction velocities, and F-wave latencies in POEMS syndrome. These features may be useful for the differentiation between POEMS syndrome and CIDP.

[Familial and sporadic distal myopathy with rimmed vacuoles: comparison of the clinical, pathological, laboratory test and follow-up data].

OBJECTIVE: To compare the clinical, pathological, laboratory test and follow-up data between familial and sporadic patients with distal myopathy with rimmed vacuoles (DMRV) and discuss the characteristics of this disorder in Chinese population. METHODS: The clinical and pathological features, laboratory data and follow-up results of 33 sporadic and 4 familial cases of pathologically confirmed DMRV were summarized and compared retrospectively. RESULTS: The patients age, onset age, or disease duration showed no significant difference between sporadic and familial cases; the onset pattern and affected muscle groups were also similar, but the sporadic cases showed more frequent dysmorphic features than the familial cases. The patients showed mild to moderate elevation of the muscle enzymes by one to three folds, and the familial patients had more significant elevation than the sporadic ones. No correlation was found between the disease duration and the level of muscle enzymes. The pathological findings were similar between the cases, and Gomori staining showed rimmed vacuoles and inclusion bodies without inflammatory cell infiltration. Follow-up results of 29 cases showed no significant difference between the two groups. The disease was slowly progressive and severely affected the quality of life of the patients, but did not produce obvious effect on the life expectancy. CONCLUSION: The clinical, pathological and laboratory data of Chinese DMRV patients are basically similar to those of Japanese cases. Sporadic cases tend to show more dysmorphic features than the familial ones, and occasional sporadic cases have early disease onset in early childhood.

[MyoD mRNA expression in skeletal muscle of patients with myotonic dystrophy].

OBJECTIVE: To explore the mRNA expression of MyoD gene in the skeletal muscles of myotonic dystrophy (MD) patients. METHODS: Muscle biopsy specimens were obtained from the biceps muscles of arm of 4 MD patients and 4 healthy controls. Semi-quantitative reverse transcription polymerase chain reaction was performed to evaluate the mRNA expression of MyoD in the specimens. RESULTS: The mRNA expression index of MyoD of the MD patients was (0.267 +/- 0.114), significantly lower than that of the healthy controls [(0.788 +/- 0.136), P = 0.001]. CONCLUSION: Down-regulated mRNA expression of MyoD gene is involved in the mechanism of DM.