The role of interleukin-6 trans-signalling on cardiovascular dysfunction in inflammatory arthritis.

OBJECTIVES: Cardiovascular (CV) mortality in RA patients is 50% higher than in the general population. There is increasing recognition that systemic inflammation is a major driver of this. IL-6 is implicated in cardiovascular disease (CVD) in the general population but its role in CVD in RA is undefined. Of the two modes of IL-6 signalling, trans-signalling is pro-inflammatory whereas classical signalling is linked with inflammation resolution. This study examines the role of IL-6 trans-signalling in CVD in a mouse model and patients with RA. METHODS: Myography determined the effect of IL-6 trans-signalling blockade, using sgp130Fc, on aortic constriction in murine collagen-induced arthritis. Serum CCL2 and sVCAM-1 as soluble biomarkers of sIL-6R trans-signalling were investigated in a human cross-sectional study. An observational longitudinal study investigated the association between these biomarkers and progression of subclinical atherosclerosis in early RA by measuring carotid intima-media thickness (CIMT). RESULTS: sgp130Fc reduced arthritis severity, serum CCL2 and sVCAM-1 and restored vascular function in collagen-induced arthritis (CIA). In established RA, sVCAM-1 correlated with the 28-joint DAS (DAS28) and CV risk. In early RA, baseline DAS28 was associated with CIMT change at 6 months. CIMT 'rapid progressors' at 12 months had higher baseline sVCAM-1, haemoglobin A1c, cholesterol:high-density lipoprotein cholesterol ratio and LDL cholesterol. CONCLUSIONS: IL-6 trans-signalling plays a pivotal role in vascular dysfunction in CIA. In early RA, sVCAM-1 was associated with progression of subclinical atherosclerosis. Inflammation from RA onset in CVD-susceptible individuals may accelerate atherosclerosis. IL-6 trans-signalling blockade may be beneficial to RA patients and perhaps for atherosclerosis in the general population.

Expression and characterization of a mutant recombinant blood coagulation factor VIII (rFVIII (m)).

In an earlier study, a site directed mutant rFVIII (rFVIII(m), Arg(336) --> Gln(336)) expressed in baculovirus-insect cell (Sf9) system was found to sustain high level activity during incubation at 37 degrees celsius for 24 h while the cofactor activity of normal plasma was declined steadily. In this study, a mutant B-domain deleted rFVIII(m), Arg(336) --> Gln(336) expressed in baculovirus-insect cell (Sf9) system was characterized for its enzymatic and chemical properties. The expressed rFVIII(m) and plasma FVIII (pFVIII) were purified by immunoaffinity column chromatography and identified by Western blot analysis. The partially purified rFVIII(m) exhibited cofactor specific activity of 2.01 x 10(3)units/mg protein. The molecular weight of rFVIII(m) ranged between 40 to 150 kDa with a major band at 150 kDa. Treatment of both rFVIII(m) and pFVIII with thrombin increased their cofactor activity in a similar pattern. Treatment of both the activated rFVIII(m) and native FVIII with APC decreased their cofactor activities, however, the former exhibited a slower decrease than the latter, although no significant difference was present. rFVIII(m) formed a complex with vWF, resulting in a stabilized form, and the lag period of thrombin-mediated activating was extended by vWF association. These results implicated that rFVIII(m) expressed in baculovirus-insect cell system had a comparable capacity as FVIII cofactor activity and might be a good candidate for the FVIII replacement therapy for hemophilia A patients.

Immune reactivity of recombinant group 2 allergens of house dust mite, Dermatophagoides pteronyssinus, and Dermatophagoides farinae.

The group 2 allergens of Dermatophagoides pteronyssinus (Der p) and Dermatophagoides farinae (Der f) are the major source of allergens for patients allergic to house dust mites (HDMs). Previous studies have reported the existence of several polymorphic residues of Der p 2 and Der f 2. In this study, recombinant group 2 allergens of Der p (rDer p 2) and Der f (rDer f 2) were produced in E. coli from the major isoforms of each cDNA, in order to evaluate their usefulness for the detection and standardization of allergens, and for the immunotherapy of patients allergic to HDMs in Korea. cDNAs of the major isoforms of Der p 2 and Der f 2 were prepared from HDMs found in -Korean houses. The IgE-binding activities of the prepared rDer p 2 and rDer f 2 were analyzed using a Western blot immunodetection system and ELISA in the pooled sera of 10 patients allergic to HDM. Both rDer p 2 and rDer f 2 bound to IgE in the pooled sera, and their activities were comparable to that of Der p 2 in HDMs. The rDer p 2-specific IgE level was higher than the rDer f 2-specific IgE level in patients' sera. The specificity of the monoclonal antibodies raised against both isoforms was analyzed by ELISA and immunogenicities of the antibodies were evaluated. Two out of four clones of rDer p 2-specific mouse monoclonal antibodies (IgG) reacted with both rDer p 2 and rDer f 2, whereas the other two did not react with rDer f 2. rDer f 2-specific monoclonal antibody reacted with both rDer f 2 and rDer p 2. The cross-reactivity of rDer p 2 and rDer f 2-specific monoclonal antibodies with both recombinant allergens indicates that epitopes responding to these antibodies are present. rDer p 2 and rDer f 2 may be useful for the detection and standardization of group 2 allergens of HDM and for the diagnosis and immunotherapy of patients allergic to HDM in Korea.

NADPH oxidase-dependent generation of lysophosphatidylserine enhances clearance of activated and dying neutrophils via G2A.

Exofacial phosphatidylserine (PS) is an important ligand mediating apoptotic cell clearance by phagocytes. Oxidation of PS fatty acyl groups (oxPS) during apoptosis reportedly mediates recognition through scavenger receptors. Given the oxidative capacity of the neutrophil NADPH oxidase, we sought to identify oxPS signaling species in stimulated neutrophils. Using mass spectrometry analysis, only trace amounts of previously characterized oxPS species were found. Conversely, 18:1 and 18:0 lysophosphatidylserine (lyso-PS), known bioactive signaling phospholipids, were identified as abundant modified PS species following activation of the neutrophil oxidase. NADPH oxidase inhibitors blocked the production of lyso-PS in vitro, and accordingly, its generation in vivo by activated, murine neutrophils during zymosan-induced peritonitis was absent in mice lacking a functional NADPH oxidase (gp91phox-/-). Treatment of macrophages with lyso-PS enhanced the uptake of apoptotic cells in vitro, an effect that was dependent on signaling via the macrophage G2A receptor. Similarly, endogenously produced lyso-PS also enhanced the G2A-mediated uptake of activated PS-exposing (but non-apoptotic) neutrophils, raising the possibility of non-apoptotic mechanisms for removal of inflammatory cells during resolution. Finally, antibody blockade of G2A signaling in vivo prolonged zymosan-induced neutrophilia in wild-type mice, whereas having no effect in gp91phox-/- mice where lyso-PS are not generated. Taken together, we show that lyso-PS are modified PS species generated following activation of the NADPH oxidase and lyso-PS signaling through the macrophage G2A functions to enhance existing receptor/ligand systems for optimal resolution of neutrophilic inflammation.

Immunization with adenoviral vectors carrying recombinant IL-12 and E7 enhanced the antitumor immunity to human papillomavirus 16-associated tumor.

OBJECTIVE: Human papillomavirus (HPV) infection play a significant role in cervical carcinogenesis, and HPV oncoprotein E7 has important functions in the formation and maintenance of cervical cancers. Interleukin-12 (IL-12) has been reported to induce cellular immune responses, and has also been demonstrated to suppress the growth of tumors and the expression of E7. Here, we investigate the utility of adenovirus E7 (AdE7) and adenovirus IL-12 (AdIL-12) for protection against TC-1 tumor using an animal model. METHODS: The antitumor effects induced by AdIL-12 and/or E7 were assessed by measurements of tumor size. E7-specific antibody and INF-gamma production in sera were measured, as were T-helper cell proliferative responses. Cytotoxic T-lymphocytes (CTL) and T cell subset depletion studies were also performed. RESULTS: Infection of tumor sites with a combination of AdIL-12 and AdE7 resulted in an antitumor effect which was significantly more profound than that which resulted from singular infections with either AdIL-12 or AdE7. Combined infection resulted in regression of 9-mm-sized tumors in approximately 80% of our experimental animals as compared to the PBS group. Serum levels of E7-specific antibody and INF-gamma production, as well as T-helper cell proliferative responses, were found to be significantly higher in coinfected with AdIL-12 and AdE7 group than in single infection with either AdIL-12 or AdE7 group. CTL responses only exhibited by the AdIL-12 and AdE7 coinjected group suggested that these tumor suppression effects were mediated primarily by CD8+ and, to a lesser degree, by CD4+ T cells. CONCLUSION: Combined injection with adenovirus carrying IL-12 and E7 induced significant antitumor immunity against TC-1 tumors. They may prove useful in clinical applications for the treatment of HPV-associated tumors.

Immunization with adenoviral vectors carrying recombinant IL-12 and E7 enhanced the antitumor immunity against human papillomavirus 16-associated tumor.

PURPOSE: Human papillomavirus (HPV) infection has a significant role in cervical carcinogenesis, and HPV oncoprotein E7 plays an important part in the formation and maintenance of cervical cancer. Interleukin-12 (IL-12) has been reported to induce a cellular immune response, and to suppress the tumor growth and the E7 production. Here we describe the use of adenoviral delivery of the HPV 16 E7 subunit (AdE7) along with adenoviral delivery of IL-12 (AdIL-12) in mice with HPV-associated tumors. MATERIALS AND METHODS: Mice were injected with TC-1 cells to establish TC-1 tumor, and then they were immunized with AdIL-12 and/or AdE7 intratumorally. The anti tumor effects induced by AdIL-12 and/or E7 were evaluated by measuring the size of the tumor. E7-specific antibody and INF-gamma production in sera, and the T-helper cell proliferative responses were then measured. Cytotoxic T-lymphocyte (CTL) and T cell subset depletion studies were also performed. RESULTS: Combined AdIL-12 and AdE7 infection at the tumor sites significantly enhanced the antitumor effects more than that of AdIL-12 or AdE7 single infection. This combined infection resulted in regression of the 9 mm sized tumors in 80% of animals as compare to the PBS group. E7-specific antibody and INF-gamma production in the sera, and the T-helper cell proliferative responses were significantly higher with coinfection of AdIL-12 and AdE7 than with AdIL-12 or AdE7 alone. CTL response induced by AdIL-12 and AdE7 in the coinjected group suggested that tumor suppression was mediated by mostly CD8+ and only a little by the CD4+ T cells. CONCLUSION: IL-12 and E7 application using adenovirus vector showed antitumor immunity effects against TC-1 tumor, and this system could be use in clinical applications for HPV-associated cancer.

Photodynamic effects of Radachlorin on cervical cancer cells.

PURPOSE: Photodynamic therapy (PDT) is a novel treatment modality, which produces local tissue necrosis with laser light following the prior administration of a photosensitizing agent. Radachlorin has recently been shown to be a promising PDT sensitizer. In order to elucidate the antitumor effects of PDT using Radachlorin on cervical cancer, growth inhibition studies on a HPV-associated tumor cell line, TC-1 cells in vitro and animals with an established TC-1 tumor in vivo were determined. MATERIALS AND METHODS: TC-1 tumor cells were exposed to various concentrations of Radachlorin and PDT, with irradiation of 12.5 or 25 J/cm(2) at an irradiance of 20 mW/cm(2) using a Won-PDT D662 laser at 662 nm in vitro. C57BL/6 mice with TC-1 tumor were injected with Radachlorin via different routes and treated with PDT in vivo. A growth suppression study was then used to evaluate the effects at various time points after PDT. RESULTS: The results showed that irradiation of TC-1 tumor cells in the presence of Radachlorin induced significant cell growth inhibition. Animals with established TC-1 tumors exhibited significantly smaller tumor sizes over time when treated with Radachlorin and irradiation. CONCLUSION: PDT after the application of Radachlorin appears to be effective against TC-1 tumors both in vitro and in vivo.