New potential therapy for orthotopic bladder carcinoma by combining HVJ envelope with doxorubicin.

PURPOSE: To establish a new therapeutic method to treat bladder carcinoma, we investigated the therapeutic potential of doxorubicin hydrochloride (DXR) combined with hemagglutinating virus of Japan-envelope vector (HVJ-E) in an orthotropic mouse bladder cancer model. METHODS: DXR and/or HVJ-E were instilled into the bladder after implantation of MB49 cells. Antitumor effects of combination therapy were evaluated by histological analysis of the bladder on day 14 after tumor implantation. The survival rate of MB49-disseminated mice was examined for 60 days after single or double administration of DXR alone or DXR/HVJ-E. The surviving mice were re-challenged with intravesical injection of MB49 cells, and the bladder was observed after 3 weeks. RESULTS: Combined intravesical instillation of HVJ-E and DXR resulted in a significantly higher rate of tumor-free mice (11/21) compared with mice treated using DXR alone (3/19, P<0.05). Median survival was >60 days for intravesical instillation of HVJ-E and DXR, compared with the 29 days for DXR instillation alone (P<0.05). After combination therapy, surviving mice formed no tumors in the bladder following intravesical re-instillation of MB49. CONCLUSIONS: HVJ-E increased antitumor effects in combination with chemotherapeutic agent (DXR). Antitumor immunity appeared to be enhanced using HVJ-E.

PAR-2 deficient CD4+ T cells exhibit downregulation of IL-4 and upregulation of IFN-gamma after antigen challenge in mice.

BACKGROUND: To investigate the functional role of protease activated receptor (PAR) -2 in T lymphocytes, we analyzed TCR-mediated inflammatory cytokine production using PAR-2 deficient (KO) and wild type (WT) mice. METHODS: Production of serum IgE and cytokines by spleen CD4+ T cells was determined in OVA-sensitized and OVA-challenged mice of PAR-2 KO in contrast to WT mice. Phosphorylation of JNK1 and 2 was determined by Western blotting. RESULTS: A reduction in serum levels of IgE and IL-4 production by splenic CD4+ T cells from OVA-sensitized and OVA-challenged KO mice compared to WT mice was observed. By contrast, IFN-gamma production was upregulated after antigen stimulation in KO mice. Anti-CD3-mediated phosphorylation of JNK1 was upregulated in splenic CD4+ T cells from KO mice compared to WT mice. CONCLUSIONS: PAR-2 participates in the regulation of T cell cytokine production that may be caused by modulation of JNK1 phosphorylation.

Cold response of the bladder in guinea pig: involvement of transient receptor potential channel, TRPM8.

OBJECTIVES: To address the physiologic role of TRPM8, one of the transient receptor potential channels, we investigated the bladder cooling reflex and the effect of menthol on it in the guinea pig. METHODS: Single cystometry in female Hartley guinea pigs was performed with high-speed infusion (60 mL/hr) under urethane anesthesia (1 g/kg intraperitoneally). The volume threshold for micturition (VT) and micturition pressure were determined. The distribution of TRPM8 in the S1 dorsal root ganglion (DRG) was also examined by immunostaining. RESULTS: Intravesical infusion of saline containing menthol (0.6 mM) at 38 degrees C markedly decreased the VT and increased micturition pressure. Although cold saline itself (4 degrees C) had little effect on VT or micturition pressure, the VT was significantly decreased in a temperature-dependent manner when the bladder was pretreated with menthol. This decrease in the VT was not observed in animals that received hexamethonium pretreatment (10 mg/kg intravenously), which blocks the spinal reflex, or capsaicin (1 mM intravesically), which causes deafferentation of capsaicin-sensitive C-fiber afferent. Immunohistochemical analysis revealed that TRPM8 is expressed in small-diameter neurons in guinea pig S1 dorsal root ganglions. CONCLUSIONS: The results of our study showed that the bladder cooling reflex is observed in guinea pigs if the animals were pretreated with menthol. This reflex was sensitive to ganglion blockade or capsaicin-sensitive C-fiber deafferentation and might be mediated by C-fiber activation through TRPM8.

CRTH2 is a prominent effector in contact hypersensitivity-induced neutrophil inflammation.

Chemoattractant receptor-homologous molecule expressed on Th2 lymphocytes, CRTH2, is a cognate receptor for prostaglandin (PG) D(2) and, in humans, is suggested to play a functional role in Th2-dependent allergic inflammation. While peripheral blood leukocytes expressing high levels of surface CRTH2 have been detected in disease, little is known of the functional significance of CRTH2 in disease etiology. We have utilized a Th2-dependent murine model of FITC-induced contact hypersensitivity to assess the role, if any, CRTH2-PGD(2) may play in the elicitation or maintenance of such pathobiology. Expression of both PGD(2) and CRTH2 in lesional skin was paralleled by the release of the chemoattractants LTB(4) and the chemokine KC, as well as a profuse dermal neutrophilic and eosinophilic infiltrate, closely paralleling the acute inflammatory pathology observed in human atopic dermatitis. A small molecule CRTH2 antagonist, but not a selective PGD(2)R (DP) receptor antagonist, was able to completely abrogate these responses. Inflammatory cascades mediated by CRTH2 ligation may therefore represent an important early step in the elicitation and maintenance of Th2-dependent skin inflammation.

Essential role of MHC II-independent CD4+ T cells, IL-4 and STAT6 in contact hypersensitivity induced by fluorescein isothiocyanate in the mouse.

Contact hypersensitivity (CHS) induced by a hapten is thought to be mediated by T helper type 1 (Th1) cells. However, FITC can induce contact allergy in vivo, and in vitro studies suggest that this response is Th2-type driven. We compared CHS reactions induced by FITC or dinitrofluorobenzene (DNFB), a well-known Th1 inducing hapten, in Balb/c mice, C57/B6 mice, and several gene knock-out mice, and investigated the role of Th1/Th2 cytokines, T cell populations, eosinophils, and mast cells. Balb/c mice (Th2 dominant strain) had a stronger response to FITC than C57/B6 mice (Th1 dominant strain). The skin inflammation was characterized by edema and eosinophilia, and serum IgE levels were elevated following FITC challenge. All responses were enhanced by a second round of sensitization. Anti-TNF-alpha or anti-very late antigen-4 (VLA-4) antibody partly inhibited both FITC- and DNFB-induced CHS. Pretreatment of mice with anti-IL-4 antibody, anti-IL-5 antibody, recombinant INF-gamma, or the mast-cell depleting agent 48/80 significantly diminished edema formation, and Stat6(-/-) mice were fully protected from FITC-induced CHS, while DNFB-induced CHS was enhanced (Stat6(-/-), mast cell depletion) or not affected (anti-IL-5 antibody). Further, mice lacking CD4(+) T cells and mice lacking both CD8 and MHC II showed very little reaction at all to FITC, while the absence of CD8 T cells alone or MHC II alone conferred partial protection only. These findings indicate a contribution of MHC II-independent CD4(+) T cells and/or CD4(+) NKT cells to the Th2 response triggered by FITC in vivo, and makes FITC-induced CHS a suitable animal model for atopic dermatitis.

Gonadal histology and serum vitellogenin levels of bigeye tuna Thunnus obesus from the Northern Pacific Ocean--absence of endocrine disruption bio-indicators.

Endocrine disrupting chemicals such as organochlorines have been detected in a large number of marine fish. Histological observation of the gonads, measurement of serum vitellogenin (VTG) level and of liver polychlorinated biphenyl (PCB) content were performed to evaluate the reproductive health and the contamination with endocrine disruptors in bigeye tuna Thunnus obesus, collected in the northern Pacific Ocean in 1999 and 2000. Abnormalities commonly found in species affected by endocrine disruptors such as the presence of oocytes in the testis or elevated serum VTG levels were not found in any of males examined. Both males and females had only small amounts of liver PCB content. The results suggest that currently there is little if any risk of organochlorine contamination or endocrine disruption of gonadal function in bigeye tuna from the northern Pacific Ocean. However, further studies are necessary to evaluate the health status of the open sea fishery resources.