Rapidly progressive respiratory failure in mixed connective tissue disease: report of an autopsy case.

A 64-year-old woman presented with exertional dyspnea. The case was diagnosed as mixed connective tissue disease (MCTD) due to presence of swollen fingers, Raynaud's phenomenon, muscle weakness, positive anti-U1RNP antibody, pericarditis and interstitial pneumonia. Although the histology from a transbronchial lung biopsy (TBLB) indicated organizing pneumonia, corticosteroid therapy was postponed for two months at the patient's request. She died 8 weeks later from acute progressive interstitial pneumonia in spite of the administration of intravenous cyclophosphamide combined with prednisolone. The autopsy revealed exudative and organizing diffuse alveolar damage (DAD). Previous reports have shown that DAD is an extremely rare pulmonary complication in MCTD. This report presents a case of MCTD with acute respiratory failure. This case thus suggests that this therapy should be administered as soon as possible.

Comprehensive screening for antigens overexpressed on carcinomas via isolation of human mAbs that may be therapeutic.

Although several murine mAbs that have been humanized became useful therapeutic agents against a few malignancies, therapeutic Abs are not yet available for the majority of the human cancers because of our lack of knowledge of which antigens (Ags) can become useful targets. In the present study we established a procedure for comprehensive identification of such Ags through the extensive isolation of human mAbs that may become therapeutic. Using the phage-display Ab library we isolated a large number of human mAbs that bind to the surface of tumor cells. They were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. The Ags recognized by those clones were isolated by immunoprecipitation and identified by MS. We isolated 2,114 mAbs with unique sequences and identified 21 distinct Ags highly expressed on several carcinomas. Of those 2,114 mAbs 356 bound specifically to one of the 21 Ags. After preparing complete IgG(1) Abs the in vitro assay for Ab-dependent cell-mediated cytotoxicity (ADCC) and the in vivo assay in cancer-bearing athymic mice were performed to examine antitumor activity. The mAbs converted to IgG(1) revealed effective ADCC as well as antitumor activity in vivo. Because half of the 21 Ags showed distinct tumor-specific expression pattern and the mAbs isolated showed various characteristics with strong affinity to the Ag, it is likely that some of the Ags detected will become useful targets for the corresponding carcinoma therapy and that several mAbs will become therapeutic agents.