A dermatomyositis and scleroderma overlap syndrome with a remarkable high titer of anti-exosome antibodies.

An overlap syndrome of dermatomyositis and scleroderma is reported. The case corresponded to a 27-year-old female with a clinical picture of 14 months evolution, characterized by proximal muscles weakness, erythematous rash in wrists, knees, ankles, Gottron sign, heliotrope periorbital rash and dysphagia. A muscle biopsy was compatible with dermatomyositis; meanwhile the skin biopsy was compatible with scleroderma. Muscle enzymes were increased. Interestingly, the antinuclear antibody determination in HEp-2 cells was positive with a remarkable titer of 81,920 exhibiting a nucleolar pattern. Anti-Jo1 antibody was negative, but anti-PM/Scl-100 positive. The patient received methylprednisolone and cyclophosphamide pulses, with gradual improvement. Present report constitutes a case of overlap dermatomyositis-scleroderma syndrome, with anti-PM/Scl autoantibodies (anti-exosome). The remarkable of this case was the exceptional high antinucleolar antibody titer.

Phosphorylation profiles of 60 kD Ro antigen in synchronized HEp-2 cells.

The purpose of this study was to determine whether phosphorylation has an effect on the characteristics of the 60 kD Ro antigen throughout the cell cycle. Cell extracts of synchronized HEp-2 cells were phosphorylated in vitro with exogenous ATP, examined by SDS-PAGE and Western blot, and probed with specific anti-Ro sera. In addition, cellular ATP pools were radiolabelled in vivo with 32P. The presence of the Ro protein was detected with a molecular weight of 60 kD during all phases of the cell cycle, except at the M phase, where it was increased to 65 kD. Phosphorylation of the in vitro and in vivo cell extracts increased the molecular mass to 65 kD. Moreover immunoprecipitation assays demonstrated that Ro is hyperphosphorylated in the M phase. Phosphorylation did not change the recognition pattern of the anti-Ro sera.