Production of Antibodies against Multipass Membrane Proteins Expressed in Human Tumor Cells Using Dendritic Cell Immunization

Antibody mediated therapeutic strategies against human malignant tumors have been widely authorized and clinically applied to cancer patients. In order to develop methods to generate antibodies reactive to the extracellular domains of multipass plasma membrane proteins specifically expressed in malignant tumors, we examined the use of dendritic cells (DCs) for immunization. DCs were transduced with genes encoding the human six transmembrane epithelial antigen of prostate 1 (STEAP1), STEAP4, and seven transmembrane prostate specific G-protein coupled receptor (PSGR). Mice were immunized with these DCs and followed by repeated booster immunization with plasmids expressing each protein. The immunized mice produced significant amounts of antibodies against these proteins. Our results suggest that DC immunization is an effective method to produce antibodies reactive to extracellular regions of plasma membrane proteins with multiple-transmembrane domains, and may be useful to develop antibody mediated antitumor therapies

Prolongation of total permissible circulatory arrest duration by deep hypothermic intermittent circulatory arrest

AbstractObjective: We determined whether the duration of permissible circulatory arrest could be prolonged by deep hypothermic intermittent circulatory arrest. Methods: Twenty-five beagles were cooled on bypass to 18° C to initiate deep hypothermia that was maintained for 3 hours. Five protocols were then studied: group 1, uninterrupted bypass during hypothermia; group 2, arrest for 40 minutes during hypothermia; group 3, arrest for 60 minutes during hypothermia; group 4, arrest for 80 minutes during hypothermia; and group 5, intermittent circulatory arrest, consisting of six cycles of 20 minutes of arrest followed by 10 minutes of systemic recirculation during hypothermia (total, 120 minutes of arrest). The oxyhemoglobin concentration in the brain was measured with near infrared spectrophotometry. Results: In groups 2, 3, and 4, the oxyhemoglobin concentration in the brain decreased continuously after arrest, finally reaching a plateau after 24.9 ± 1.2 minutes. This finding suggested that the available cerebral oxyhemoglobin was depleted. In contrast, the available cerebral oxyhemoglobin was not depleted during hypothermic intermittent arrest in group 5. The mitochondrial respiratory control index was significantly lower in group 4 than in the other groups (p < 0.05). However, there were no significant differences in the respiratory control index for groups 1, 2, 3, and 5. Moreover, the formation of brain edema was significantly lower in group 5 than in the other groups (p < 0.05). Conclusions: These results indicate that deep hypothermic intermittent arrest can increase the duration of total permissible circulatory arrest and will be a useful modality when prolonged arrest is anticipated. (J Thorac Cardiovasc Surg 1998;116:163-70

STEAP4 regulates focal adhesion kinase activation and CpG motifs within STEAP4 promoter region are frequently methylated in DU145, human androgen-independent prostate cancer cells

The possible roles of STEAP4 in cancer progression have not been reported. In this study, we report that STEAP4 expression is able to inhibit anchorage-independent cell growth. We also demonstrate that STEAP4 associates with focal adhesion kinase (FAK) and regulate the activity of FAK through Y397 phosphorylation. Furthermore, we show that CpG sequences in STEAP4 promoter region were frequently methylated in DU145, androgen-independent prostate cancer cells. Demethylation treatment induced STEAP4 expression in DU145, suggesting the possibility that STEAP4 expression in cancer cells is in part epigenetically regulated. Collectively, these data demonstrate a novel function of STEAP4 and that STEAP4 may play an important role in tumor malignancy

Refractoriness of intestinal Behçet's disease with myelodysplastic syndrome involving trisomy 8 to medical therapies - our case experience and review of the literature.

Background/Aims: Gastrointestinal lesions of Behçet's disease (BD) are often refractory to medical therapy and sometimes result in serious comorbidities such as gastrointestinal perforation and massive bleeding. There are several reports of patients with BD comorbid with myelodysplastic syndrome (MDS) involving trisomy 8 that frequently have intestinal lesions refractory to conventional medical therapy. Little is known about the efficacy of infliximab (IFX) for these intestinal lesions. Methods: We present 2 cases of intestinal BD with MDS involving trisomy 8 who did not respond to IFX, and review previous reports of BD with MDS involving trisomy 8 concerning their responsiveness to conventional medical therapy. Results: Among 31 previously reported cases that received medical treatment for BD, 19 (61.3%) showed temporary improvement of the BD symptoms, 9 (29.0%) deteriorated, and 3 (9.7%) showed no change. All of the 9 cases that showed deterioration had intestinal lesions. Our 2 cases failed to respond to IFX, resulting in a poor prognosis. Conclusions: IFX might not be effective for improving intestinal BD comorbid with MDS involving trisomy 8. Trisomy 8 is associated with the BD prognosis and refractoriness to conventional medical therapy

Leukocyte and platelet depletion with a blood cell separator: Effects on lung injury after cardiac surgery with cardiopulmonary bypass

AbstractThis study was undertaken to assess the effects of leukocyte and platelet depletion on postoperative lung injury in 42 patients who underwent heart operations. Blood was serially sampled before, during, and after cardiopulmonary bypass, and leukocyte count, platelet count, and thromboxane B2 6-keto-PGF1α, leukocyte elastase, thrombin–antithrombin III complex, and D-dimer levels were determined. Postoperative respiratory function was assessed based on analyses of oxygenation and carbon dioxide elimination. Leukocyte and platelet depletion was performed in 21 patients (experimental group) but not in another (control group). In the experimental group, leukocytes and platelets were removed continuously by means of the blood cell separator CS-3000, beginning immediately after the start of the operation and ending 1 hour after the release of aortic occlusion. Leukocyte elastase, thromboxane B2, ratio of thromboxane B2 to 6-keto-PGF1α, thrombin–antithrombin III complex, and D-dimer were significantly lower in the experimental group than in the control group. Of the various indexes of oxygenation, arterial oxygen tension was significantly higher in the experimental group and the alveolar-arterial oxygen pressure difference and respiratory index were significantly lower in the experimental group. The positive end-expiratory pressure needed to achieve an appropriate arterial oxygen tension was significantly lower in the experimental group. The elimination of carbon dioxide was lower in the experimental group. Depletion of leukocytes and platelets reduced respiratory dysfunction after heart operations with cardiopulmonary bypass. It was particularly effective in patients with a low preoperative oxygenation capacity and in those for whom an extended period of cardiopulmonary bypass was required. (J THORAC CARDIOVASC SURG 1996;111:45-54