A 77-year-old patient was referred for progressive fatigue and dyspnea on exertion. Preoperative imaging evaluations including transthoracic echocardiography and computed tomography were suggestive of a chronic ascending aortic dissection with an intramural hematoma. Intraoperatively, the intramural structure was identified as an abscess cavity.

Anti-calretinin antibodies are useful to differentiate adenocarcinomas from malignant mesotheliomas of the lung. Therefore, calretinin expression is rarely reported for sarcomatoid mesotheliomas. Anti-podoplanin antibodies (eg D2-40) react with lymphatic endothelia, Kaposi's sarcoma, lymphangioma and mesotheliomas. For the interpretation of spindle cell lesions of the pleura, knowledge of calretinin and D2-40 expression frequencies in sarcomatoid mesothelioma is desirable. To systematically investigate the sensitivity of calretinin and D2-40 antibodies in epithelioid and sarcomatoid areas of malignant mesotheliomas, a tissue microarray with 341 malignant mesotheliomas, including 112 epithelioid, 46 sarcomatoid and 183 biphasic tumors was constructed. Epithelioid and sarcomatoid differentiated tumor areas were clearly separated within the tissue microarray. Expression of calretinin and D2-40 was separately studied in epithelioid and sarcomatoid areas by immunohistochemistry. Calretinin expression was found in 91% of epithelioid and 57% of sarcomatoid tumor areas. D2-40 immunostaining was present in 66% of the epithelioid and 30% of the sarcomatoid tumor areas. A combination of calretinin and D2-40 increased the sensitivity in epithelioid tumor areas to 0.96 and in sarcomatoid tumor areas to 0.66. These data indicate that a combination of calretinin and D2-40 will improve diagnostic accuracy for spindle cell lesions of the pleura, whereas almost all epithelioid mesotheliomas are identified by calretinin alone.

Background: CD26 is a T-cell co-stimulator, and interacts with adenosine deaminase, human immunodeficiency virus (HIV) Tat-1 protein and extracellular matrix. It possesses dipeptidylpeptidase 1V (DPP TV) catalytic activity, which is linked to its co-stimulatory efficacy. We investigated the effect of specific DPP IV systemic activity inhibition on acute pulmonary rejection.Methods: Rat single-lung transplantation (Tx) was performed (LBNF1/LEW donor/recipient) in two groups (n = 12). Group I (n = 6) received daily treatment with a Pro-Pro-diphenylphosphonate derivative (AB197), and Group II served as an untreated control. At Day 5 post-Tx, ventilatory parameters, cytotoxicity and mixed lymphocyte reaction were analyzed and staining for ISHLT rejection grade and proliferating cell nuclear antigen (PCNA) was performed.Results: Treatment with AB192 abrogated acute rejection and preserved pulmonary function up to Day 5 post-Tx for PO2 (Group II: 24.9 +/- 6.9 mm Hg; Group I: 149.5 +/- 24.3 min Hg; p < 0.001), P-CO2 Group II: 53.3 +/- 13.6 mm Hg; Group L 39.0 +/- 9.8 min Hg; p < 0.05) and peak airway pressure (Group II: 50.7 +/- 17.2 mm Hg; Group 1: 20.2 +/- 10.0 min Hg; p < 0.01). Controls showed moderate/severe rejection (ISHLT Grade A2 or 3), grafts from inhibited hosts revealed no/mild rejection (Grade A0 to 2: Group 11: 2.8 +/- 0.3; Group 1: 1.25 +/- 1.0; P < 0.005). Proliferating cell nuclear antigen (PCNA) staining of rejection-associated cellular infiltrates showed a significant reduction in positivity in perivascular infiltrates (34 +/- 11.5%; p < 0.05) and bronchial surface epithelium (31.7 +/- 10.6%; p < 0.05) in Group I vs Group 11 (55.9 +/- 8.4% and 57.2 +/- 4.5%).Conclusions: Irreversible enzymatic inhibition of DPP IV has been shown to abrogate acute pulmonary rejection, maintain pulmonary function, and preserve histomorphologic architecture. These results extend earlier findings and illustrate the role of CD26/DPP IV in alloantigen-mediated immune responses.