A novel autoantibody to a 155-kd protein is associated with dermatomyositis

OBJECTIVE

In polymyositis and dermatomyositis (DM), identified autoantibodies occur in <50% of adult patients and in a smaller proportion of children. This study was undertaken as part of a larger effort to define novel autoantibodies that assist in the clinical evaluation of myositis.

METHODS

Sera from children and adults satisfying criteria for idiopathic inflammatory myopathies and from patients with other connective tissue diseases (CTDs), patients with noninflammatory myopathies, and healthy individuals were tested for autoantibodies by immunoprecipitation (IP). A previously unrecognized autoantibody that immunoprecipitated a 155-kd protein along with a weaker 140-kd protein was seen. When the presence of this anti-p155 autoantibody in test sera was suggested based on IP results, it was confirmed by immunoblotting of immunoprecipitates.

RESULTS

Sera from 51 of 244 myositis patients (21%), including 30 with juvenile DM (29%), 5 with juvenile CTD-associated myositis (33%), 8 with adult DM (21%), 6 with cancer-associated DM (75%), and 2 with adult CTD-associated myositis (15%), were found to have anti-p155 autoantibody. One of 49 patients with lupus, and none of 89 others without myositis, had anti-p155. Caucasian patients with anti-p155 had a unique HLA risk factor, DQA1*0301 (odds ratio 5.4, corrected P = 0.004). In adults with anti-p155, of several clinical features assessed only the frequency of V-sign rash was increased, but patients with this antibody were clinically distinct from those with autoantibodies to aminoacyl-transfer RNA synthetases.

CONCLUSION

A newly recognized autoantibody, anti-p155, is associated with DM and cancer-associated DM, and is one of the most common autoantibodies in this condition, occurring as frequently in children as in adults. The clinical features and immunogenetics associated with anti-p155 differ from those associated with antisynthetases.

Modern therapeutic approach for high grade astrocytoma: intracranial Ir-192 brachytherapy

Prognosis of high-grade astrocytoma has been extremely disappointing and the median survival of patients with this tumor is less than 10 months at best. The most common cause of failure is local persistence of the tumor. Many neuro-oncologists have now turned to an alternative therapeutic approach involving brain brachytherapy (interstitial implantation) for the treatment of high-grade astrocytomas because in this manner a higher dose can be delivered to the tumor bed without excessively irradiating the surrounding normal brain tissue. Brachytherapy has shown some evidence of superior results in survival of malignant astrocytomas if properly performed by a qualified brachytherapy team. The objective of this report is to discuss the rationale and technique of brachytherapy in the management of high-grade astrocytoma as well as future prospects concerning this particular treatment modality.

Lysophospholipase activity in rabbit skeletal muscle

Skeletal muscle contains appreciable lysophospholipase activity which is differentiated by muscle type with red muscle subcellular fractions having greater activity than the corresponding white ones.