Changes in the immune cell population and cell proliferation in peripheral blood after gemcitabine-based chemotherapy for pancreatic cancer.

PURPOSE: Regulatory T cells (Tregs) play a role in the immunosuppressive state in pancreatic cancer patients. We aimed to evaluate the changes of immune cells population including Tregs caused by gemcitabine (GEM)-based chemotherapy. METHODS: Fifty-three patients with pancreatic cancer were enrolled in this study, of which 32 received GEM- based chemotherapy. Blood samples were collected before and at least 2 weeks after the last dose of chemotherapy. The peripheral blood mononuclear cells (PBMCs) were subjected to flow cytometry analysis after labeling with anti-CD4, anti-CD25, and anti-Foxp3 antibodies. Other lymphocytes and NK cell markers were also measured. The proliferative capacity of PBMCs stimulated with anti-CD3 was analyzed using H(3) thymidine. RESULTS: The percentage and number of Tregs were significantly decreased after chemotherapy (p = 0.032, p = 0.003, respectively). The other immune cells and the proliferative capacity did not change. CONCLUSION: This study showed that GEM-based chemotherapy produced an immunomodulatory effect via the depletion of Tregs.

Direct effects of IL-4/IL-13 and the nematode Nippostrongylus brasiliensis on intestinal epithelial cells in vitro.

Nematode infections induce the upregulation of mucin- and glycosylation-related genes in intestinal epithelial cells in vivo. However, the factor(s) that induce these changes in epithelial cells have not been fully elucidated. In the present study, we analysed the effects of the Th2 cytokines IL-4 and IL-13 and the excretory-secretory (ES) product of the nematode Nippostrongylus brasiliensis on the gene expression of the major mucin core peptide MUC2, the sialyltransferase ST3GalIV (Siat4c) and the sulphotransferase HS3ST1 in intestinal epithelium-derived IEC-6 cells by quantitative reverse transcription (RT)-PCR. The administration of IL-4 and IL-13 resulted in a significant upregulation of ST3GalIV and HS3ST1 gene transcription, but had no effect on MUC2, in IEC-6 cells. RT-PCR studies also demonstrated the constitutive expression of IL-13Ralpha1 and IL-4R in IEC-6 cells. On the other hand, the ES product induced upregulation of ST3GalIV, but not HS3ST1 or MUC2, while coadministration of IL-13 and the ES product induced a slight but significant upregulation of MUC2. Co-incubation of live N. brasiliensis adult worms with IEC-6 cells resulted in the upregulation of ST3GalIV and MUC2. These results suggested that HS3ST1 gene expression is strictly regulated by IL-4/IL-13, while ST3GalIV and MUC2 gene expressions are regulated by redundant mechanisms.

Intrinsically bent DNA in replication origins and gene promoters.

Intrinsically bent DNA is an alternative conformation of the DNA molecule caused by the presence of dA/dT tracts, 2 to 6 bp long, in a helical turn phase DNA or with multiple intervals of 10 to 11 bp. Other than flexibility, intrinsic bending sites induce DNA curvature in particular chromosome regions such as replication origins and promoters. Intrinsically bent DNA sites are important in initiating DNA replication, and are sometimes found near to regions associated with the nuclear matrix. Many methods have been developed to localize bent sites, for example, circular permutation, computational analysis, and atomic force microscopy. This review discusses intrinsically bent DNA sites associated with replication origins and gene promoter regions in prokaryote and eukaryote cells. We also describe methods for identifying bent DNA sites for circular permutation and computational analysis.

Intrinsically bent DNA in replication origins and gene promoters

Intrinsically bent DNA is an alternative conformation of the DNA molecule caused by the presence of dA/dT tracts, 2 to 6 bp long, in a helical turn phase DNA or with multiple intervals of 10 to 11 bp. Other than flexibility, intrinsic bending sites induce DNA curvature in particular chromosome regions such as replication origins and promoters. Intrinsically bent DNA sites are important in initiating DNA replication, and are sometimes found near to regions associated with the nuclear matrix. Many methods have been developed to localize bent sites, for example, circular permutation, computational analysis, and atomic force microscopy. This review discusses intrinsically bent DNA sites associated with replication origins and gene promoter regions in prokaryote and eukaryote cells. We also describe methods for identifying bent DNA sites for circular permutation and computational analysis.

Monocyte adherence to Paracoccidioides brasiliensis, zymosan-C3b and erythrocyte-hemolysin in patients with paracoccidioidomycosis.

Independent and dependent (C3b/Fc receptors) opsonic adherence ability of monocytes from thirty-three patients with acute or chronic paracoccidioidomycosis and from 13 healthy individuals were studied in the presence of Paracoccidioides brasiliensis (Pb), Paracoccidioides brasiliensis opsonized by patient's serum (PbPS) or normal serum (PbNS), zymosan opsonized by fresh sera from healthy donors (ZyNS) and erythrocytes opsonized by hemolysin (EA). Statistically significant differences concerning the percentage of adhered monocytes to PbPS (number of adhered monocytes/total number of monocytes) were detected between control and chronic (active and inactive) groups. Significant differences in relationship to the mean number of PbPS (number of fungi in monocytes/total number of monocytes) were also observed between control and chronic active mycosis. Present data suggest that patients with chronic disease have more ability in the first step of phagocytic activity, considered as the main effector mechanism to control the dissemination and severity of paracoccidiodomycosis.