Therapeutic effect of ceftizoxime on severe infectious complications in blood disorders. Tohkai Research Group on Infections in Hematopoietic Disorders

Ceftizoxime (CZX) was given by intravenous injection in daily doses of 2-8 g to 103 patients with severe infections complicating hematopoietic disorders. The clinical effect was evaluated in 95 of the 103 patients. The causative organisms were identified in 22 patients but were unknown in the remaining 73. Infected sites were the respiratory tract, urinary tract, soft tissue, and blood. The overall effectiveness rate (inclusive of marked and moderate) was 61.1% (58/95). The effectiveness rate was 63.6% (14/22) in patients in whom the causative organisms were identified and 60.3% (44/73) in patients in whom the causative organisms could not be identified and 60.0% (18/30) in 30 patients with less than 100 neutrophils per mm3 before treatment. No side effects were noted except drug fever in 1 patient. Abnormal hepatic function was seen in 6 patients but was not attributed to the drug in any case. The results indicate that CZX is a safe and useful antibiotic for the treatment of severe infectious complications in hematopoietic disorders.     

Differential cell division history between neutrophils and macrophages in their development from granulocyte-macrophage progenitors

The appearance of monocytes before neutrophils in the blood during haematopoietic recovery in myelosuppressive patients is commonly observed, thus suggesting a difference in the cell division history between these two lineages in the differentiation from granulocyte-macrophage (GM) progenitors. We investigated the cell division histories of murine GM progenitors. When analysed by the dye dilution method, GM progenitors gave rise to Gr-1+Fms+ and Gr-1+Fms- cells that passed through similar rounds of cell division during initial 5 d of culture. The Gr-1+Fms+ cells showed morphological features of monocytes, while Gr-1+Fms- cells exhibited an immature morphology of neutrophils. In the subsequent culture, a decline in the number of Gr-1+Fms+ cells was observed, while Gr-1+Fms- cells increased. The proliferation of Gr-1+Fms- cells and no cell division of Gr-1+Fms+ cells were confirmed by DNA staining, Ki-67 expression, membrane dye staining and bromodeoxyuridine incorporation. These Gr-1+Fms- cells acquired mature neutrophil morphology, whereas Gr-1+Fms+ cells became macrophages. These results demonstrate that GM progenitors generate postmitotic monocytes earlier than mature neutrophils. Our data may also offer one explanation for the rapid recovery of monocytes in comparison with neutrophils in the early phase of haematopoietic regeneration.     

Gene expression profiling of diffuse large B-cell lymphoma supervised by CD21 expression

This study investigated the gene expression profiles of 40 cases of diffuse large B-cell lymphoma (DLBCL) according to CD21 expression, a favourable prognostic factor in DLBCL. Signature genes were analysed by Gene Ontology Tree Machine, and genes concerned with the immune system and related categories were significantly upregulated in CD21⁻ DLBCLs. Of 40 DLBCLs, four were germinal centre B cell-like (GCB) and 36 non-GCB. Of the 36 non-GCB DLBCLs, 14 CD21⁺ DLBCLs showed significantly better overall survival than the 22 CD21⁻ DLBCLs ( P  =   0·036). Hierarchical cluster analysis of signature genes related to CD21 was applied to previously published data sets, resulting in two groups for each data set, CD21⁺ type DLBCLs and CD21⁻ type DLBCLs. Survival of CD21⁺ type DLBCLs was significantly better than that of CD21^– type ( P  =   0·006 and P  =   0·004, respectively). In both data sets, CD21⁺ type DLBCLs predominantly included GCB DLBCLs compared with CD21⁻ type. The top classifier gene of CD21 expression was IGHM, and the five of nine Gene Ontology categories significant in CD21^– DLBCLs included IGHM . Immunohistochemical analysis of 216 DLBCLs confirmed that overall survival of surface (s) IgM⁺ DLBCLs was significantly poorer than that of sIgM^- DLBCLs ( P  =   0·013).     

Bax induction activates apoptotic cascade via mitochondrial cytochrome c release and Bax overexpression enhances apoptosis induced by chemotherapeutic agents in DLD-1 colon cancer cells.

Cancer cells express different levels of apoptosis-promoting Bax protein. The present study evaluated whether induction of Bax initiates apoptosis and whether Bax overexpression enhances apoptosis induced by several chemotherapeutic agents in DLD-1 colon cancer cells, which originally express a high level of endogenous Bax protein and a low level of Bcl-2 protein. To investigate these two points, parental DLD-1 cells were transfected with the Tet-On Bax induction system (pTet-On and pTRE-Bax plasmids), and stable transduced cells were obtained. Induction of Bax by the Tet-On system initiated cytochrome c release from mitochondria, caspase-3 activation, and apoptosis to some extent in DLD-1 cells. Apoptosis induced by a chemotherapeutic agent, 5-fluorouracil, mitomycin C, paclitaxel, doxorubicin, or cisplatin, was enhanced by Bax overexpression. These findings suggest that Bax-overexpression-based gene therapy combined with chemotherapy would be effective in the treatment of colon cancer.     

Plasma tissue factor and tissue factor pathway inhibitor levels in patients with disseminated intravascular coagulation

We measured the plasma levels of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with disseminated intravascular coagulation (DIC) to examine the relationship between TFPI and vascular endothelial cell injury. Plasma TF (273 ± 90 pg/ml) and TFPI (252 ± 125 ng/ml) levels were significantly increased in patients with DIC compared with non-DIC patients. Plasma TF antigen level was significantly increased in pre-DIC patients (285 ± 85 pg/ml), while the plasma TFPI level (152 ± 54 ng/ml) was not markedly increased in such a state. The plasma TF/TFPI ratio was high in the pre-DIC patients (2.10 ± 0.90), and low in the DIC patients (1.40 ± 0.87) and healthy volunteers (0.84 ± 0.26). There was no significant difference between the DIC patients with a good outcome and those with a poor outcome in terms of plasma TF levels, although the plasma TFPI level in the DIC patients with a good outcome (289 ± 133 ng/ml) was significantly higher than those with a poor outcome (187 ± 75 ng/ml). During the clinical course of DIC, plasma TF antigen was increased first, and an increase of the plasma TFPI level followed the increase in plasma TF level. These findings suggest that plasma TFPI is released from vascular endothelial cells and it may reflect vascular endothelial cell injury. It is conceivable that TF and TFPI may play an important role in the onset of DIC. Am. J. Hematol. 55:169–174, 1997. © 1997 Wiley-Liss, Inc.     

Tumor-specific crosslinking of GITR as costimulation for immunotherapy

Activation of murine glucocorticoid-induced tumor necrosis factor-related receptor (mGITR) by its natural ligand (GITRL) or antiGITR agonist mAb enhances T-cell responses, inhibits regulatory T-cell (Treg)-mediated suppression and induces tumor immunity in a variety of murine tumor models. However, systemic administration of these costimulatory agents can lead to global T-cell activation and autoimmunity. To specifically manipulate the T-cell compartment in the tumor microenvironment we propose to target the tumor infiltrating T cells with a bispecific mGITRL fusion protein. For that purpose, mGITRL is linked to a single-chain antibody targeting fibroblast activation protein (FAP) as FAP expression is restricted to cancer-associated fibroblasts (CAFs) found in the stroma of epithelial cancers. AntiFAP-mGITRL fusion protein forms dimers and binds to murine GITR with 1.2?μM affinity and to murine FAP with 4.5?nM. The construct is able to costimulate CD8+ and CD4+ effector T cells resulting in increased proliferation, IFN-γ and IL-2 production. This costimulatory effect is enhanced when the fusion protein is bound to a FAP-positive cell line mimicking FAP CAFs. In suppression assays, membrane-bound antiFAP-mGITRL is 100-fold more effective in overcoming Treg-mediated suppression than unbound fusion protein. These studies suggest that targeted tumor therapy with antiFAP-mGITRL fusion protein could induce tumor rejection while minimizing autoimmune side effects.     

Humoral immune responses in patients vaccinated with 1-146 HER2 protein complexed with cholesteryl pullulan nanogel

The CHP-HER2 vaccine, comprising truncated 146HER2 protein complexed with nanogels of cholesteryl pullulan (CHP), is a novel protein antigen vaccine that elicits 146HER2-specific CD8⁺ and CD4⁺ T-cell immune responses in patients with HER2-expressing tumors. We analyzed the humoral responses in patients vaccinated with CHP-HER2 and those with CHP-HER2 plus granulocyte-macrophage colony-stimulating factor (GM-CSF). The vaccine was injected subcutaneously at a dose of 300 µg protein. Nine patients received the vaccine alone over the first four injections, followed by CHP-HER2 with GM-CSF or OK-432, whereas six received CHP-HER2 plus GM-CSF from the first cycle. 146HER2-specific IgG antibodies were induced in 14 patients, who were negative at baseline. The antibodies became detectable after the second or third vaccination and reached plateau levels after the third or fourth cycle in patients vaccinated with CHP-HER2 plus GM-CSF. In contrast, the antibodies appeared only after the third to sixth vaccination and the plateau appeared after the fourth to eighth cycle in patients vaccinated with the CHP-HER2 vaccine alone over the first four cycles. The antibodies induced by the vaccine were not reactive with HER2 antigen expressed on the cell surface in any of the patients. Epitope analysis using overlapping peptides revealed a single region in the 146HER2 protein, amino acids 127–146, in eight patients who were initially vaccinated with CHP-HER2 alone. Similarly, the same HER2 region was recognized dominantly in patients vaccinated with GM-CSF. Our results indicate that CHP-HER2 induced HER2-specific humoral responses in patients with HER2-expressing tumors and that GM-CSF seems to accelerate the responses. ( Cancer Sci 2008; 99: 601–607)