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Subcutaneous Inoculation (subcutaneous + inoculation)
Selected AbstractsEffects of age and viral determinants on chronicity as an outcome of experimental woodchuck hepatitis virus infectionHEPATOLOGY, Issue 1 2000Paul J. Cote Ph.D. Acute hepadnavirus infections either resolve or progress to chronicity. Factors that influence chronicity as an outcome of hepatitis B virus (HBV) infection in humans can be studied experimentally in the woodchuck model. Accordingly, several woodchuck hepatitis virus (WHV) inocula were characterized. Representative inocula had high titers of infectious virus (approximately 107.7 -109.5 woodchuck 50% infectious doses per milliliter [WID50% /mL] by subcutaneous inoculation), with 1 WID50% ranging between 21 and 357 physical virion particles. WHV7P1 (standard high dose, 5 × 106WID50%) produced a 72% chronicity rate (i.e., percent chronic of total infected) in neonatal woodchucks (1-3 days old). Comparable doses of WHV8P1 resulted in a lower chronicity rate in neonates (34% chronic) indicating that it represented a strain different from WHV7P1. Neonatal woodchucks were more susceptible to chronic infection by high doses of WHV7P1 (range, 65%-75% chronic) compared with 8-week-old weanlings (33% chronic) and adult woodchucks (0% chronic; i.e., all resolved). High doses of cloned wild-type viruses also induced high rates of chronicity in neonates (70%-80% chronic). Chronicity rates in neonates were decreased for low doses of WHV7P1 (500 WID50% , 9% chronic) and for high doses of a precore WHeAg-minus mutant WHV8 clone (17% chronic). Thus, both age and viral determinants can influence chronicity as an outcome of experimental WHV infection. Standardized inocula will enable the study of mechanisms that initiate and maintain chronic hepadnavirus infection and also provide a means for developing WHV carriers for therapeutic studies. [source] Cytotoxic action of phorbol esters on human pancreatic cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 7 2007Jane A. Bond Abstract We previously showed that phorbol esters are cytotoxic to human thyroid epithelial cells expressing a mutant RAS oncogene. Here we explore the generality of this finding using cells derived from pancreatic cancer, which, like thyroid, shows a high frequency of RAS mutation, but is a much greater cause of cancer mortality. The response to phorbol myristate acetate (PMA) and related agents was assessed on a panel of 9 pancreatic cancer cell lines, using a range of assays for cell growth and death in vitro and in vivo. In most lines, PMA induced non-apoptotic cell death which was, surprisingly, independent of its "classic" target, protein kinase C. With 24 hr exposure, the IC50 in the most sensitive line (Aspc-1) was <1 ng/ml (1.6 nM), with survival undetectable at concentrations ,,16 nM, and after only 1 hr exposure the IC50 was still ,,16 nM. Interestingly, the efficacy of a second phorbol ester, phorbol dibutyrate, was much lower, and the PMA analogue bryostatin-1, which is in clinical trials against other tumour types, was totally inactive. Pre-treatment of Aspc-1 cells with PMA before subcutaneous inoculation into nude mice prevented, or greatly retarded, subsequent xenograft tumour growth. Furthermore, treatment of established tumours with a single peri-tumoral injection of PMA induced extensive cell death and arrested tumour development. Taken together with recent Phase 1 clinical studies, these data suggest that activity against pancreatic cancer will be attainable by systemic administration of PMA, and point to potential novel therapeutic targets for this highly aggressive cancer. © 2007 Wiley-Liss, Inc. [source] Expression of IL-27 in murine carcinoma cells produces antitumor effects and induces protective immunity in inoculated host animalsINTERNATIONAL JOURNAL OF CANCER, Issue 3 2005Masako Chiyo Abstract A novel cytokine interleukin-27 (IL-27), composed of p28 and Epstein-Barr virus-induced gene 3 (EBI3), is produced from activated dendritic cells and is involved in an early phase of T-helper type I differentiation. We examined whether Colon 26 murine colon carcinoma cells that were retrovirally transduced with the p28 -linked EBI3 gene (Colon 26/IL-27) could produce antitumor effects in inoculated mice. Although proliferation in vitro of Colon 26/IL-27 cells was not different from that of parent cells, syngeneic BALB/c mice rejected Colon 26/IL-27 tumors inoculated and subsequently acquired tumor-specific protective immunity. In contrast, mice inoculated with Colon 26 cells transduced with either the p28 or EBI3 gene developed tumors and survival of the mice remained the same as that of the mice inoculated with parent cells. Syngeneic nude mice developed Colon 26/IL-27 tumors, but the growth was retarded compared to that of parent tumors. Depletion of natural killer cells from nude mice with anti-asialo GM1 antibody diminished the growth retardation of Colon 26/IL-27 tumors. Survival of severe combined immunodeficient mice that received subcutaneous inoculation of Colon 26/IL-27 cells was not different from that of the immunodeficient mice inoculated with parent cells. Interferon-, was produced from CD4+ and CD8+ T, and natural killer cells of the mice that rejected Colon 26/IL-27 tumors and cytotoxic activity against Colon 26 cells were also detected from the mice. These data collectively suggest that expressed IL-27 in tumors produces T cell-dependent and-independent antitumor effects and is a possible therapeutic strategy for cancer. ©2005 Wiley-Liss, Inc. [source] Screening of gastric cancer cell sublines using the adhesion methodJOURNAL OF DIGESTIVE DISEASES, Issue 3 2001Xiangrong Chen OBJECTIVE: To screen subpopulations of gastric cancer cell lines with different malignant phenotypes. METHODS: Two subpopulations from the human gastric cancer cell line MKN-45 were separated by using the laminin adhesion method. One subpopulation was less invasive and non-metastatic, whereas the other was more invasive and metastatic. The relative invasiveness and migratory capacities of the two subgroups were observed by using the Boyden chamber and by inoculating the cells into nude mice. RESULTS: The two subgroups, the laminin-adherent cells (Lm+) and the laminin non-adherent cells (Lm,), were separated. During in vitro experiments, the Lm+ cells were more invasive and their migratory ability was greater relative to the Lm, cells. The rates of tumor formation after subcutaneous inoculation in nude mice and of lung tumor foci formation after tail vein inoculation were higher in Lm+ cells than those in Lm, cells. In vivo, Lm+ cells were found to have higher metastatic potential and to be more invasive. CONCLUSIONS: In vitro, the adhesion method is a simple and time-saving way to screen a particular phenotypic cell subpopulation with a high success rate. There are discrepancies in invasiveness and migratory ability between in vitro Lm+ and Lm, cells, which suggests that these properties of gastric cancer cells are closely related to their adhesiveness to the basement membrane and extracellular matrix. [source] Vaccination with selected synovial T cells in rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 2 2007Guangjie Chen Objective This pilot clinical study was undertaken to investigate the role of T cell vaccination in the induction of regulatory immune responses in patients with rheumatoid arthritis (RA). Methods Autologous synovial T cells were selected for pathologic relevance, rendered inactive by irradiation, and used for vaccination. Fifteen patients received T cell vaccination via 6 subcutaneous inoculations over a period of 12 months. Results T cell vaccination led to induction of CD4+ Tregs and CD8+ cytotoxic T cells specific for T cell vaccine. There was selective expansion of CD4+,V,2+ Tregs that produced interleukin-10 (IL-10) and expressed a high level of transcription factor Foxp3, which coincided with depletion of overexpressed BV14+ T cells in treated patients. CD4+ IL-10,secreting Tregs induced by T cell vaccination were found to react specifically with peptides derived from IL-2 receptor ,-chain. The expression level of Foxp3 in CD4+ T cells and increased inhibitory activity of CD4+,CD25+ Tregs were significantly elevated following T cell vaccination. The observed regulatory immune responses collectively correlated with clinical improvement in treated patients. In an intent-to-treat analysis, a substantial response, defined as meeting the American College of Rheumatology 50% improvement criteria, was shown in 10 of the 15 patients (66.7%) and was accompanied by a marked improvement in RA-related laboratory parameters. Conclusion These findings suggest that T cell vaccination induces regulatory immune responses that are associated with improved clinical and laboratory variables in RA patients. [source] | ||||||||||