The new direct oral anticoagulants in special indications: rationale and preliminary data in cancer, mechanical heart valves, anti-phospholipid syndrome, and heparin-induced thrombocytopenia and beyond.

The present review will briefly summarize the interplay between coagulation and inflammation, highlighting possible effects of direct inhibition of factor Xa and thrombin beyond anticoagulation. Additionally, the rationale for the use of the new direct oral anticoagulants (DOACs) for indications such as cancer-associated venous thromboembolism (CAT), mechanical heart valves, thrombotic anti-phospholipid syndrome (APS), and heparin-induced thrombocytopenia (HIT) will be explored. Published data on patients with cancer or mechanical heart valves treated with DOAC will be discussed, as well as planned studies in APS and HIT. Although at the present time published evidence is insufficient for recommending DOAC in the above-mentioned indications, there are good arguments in favor of clinical trials investigating their efficacy in these contexts. Direct inhibition of factor Xa or thrombin may reveal interesting effects beyond anticoagulation as well.

Inhibition of antigen-induced T-cell clone proliferation by antigen-specific antibodies.

Attempts to inhibit the recognition of soluble antigens by T lymphocytes using antibodies specific for the antigen in question have been uniformally unsuccessful, in contrast to the observed specific inhibition of antibody generation by B cells. One exception is the unique situation whereby anti-hapten antisera inhibit the T-cell proliferative responses observed when hapten-specific T lymphocytes or clones are cultured with hapten-derivatized cells or proteins. The inability to inhibit T-cell functions by antigen-specific antibodies has been interpreted in several ways: (1) T cells possess a different repertoire from B cells; (2) the antibodies tested recognize epitopes present on the native antigen, whereas T cells recognize non-native (processed) structures; (3) the antigenic determinant(s) recognized by T cells on the surface of antigen presenting cells are either not accessible to antibodies, or are present in low amounts. The development of antigen-specific T-cell clones and monoclonal antibodies both specific for the same antigenic determinants now allows this question to be investigated definitively. Here, we report for the first time the specific inhibition of antigen-induced T-cell clone proliferation by a monoclonal antibody directed against the relevant soluble protein antigen.

Three Generation Family With Pattern Dystrophy and a Successful Treatment of Subfoveal Cnv Related to Pattern Dystrophy With Anti-vegf Intravitreal Injections

Purpose: To phenotype a large 3 generation Swiss family with pattern dystrophy and to report a successful result of treatment with ranibizumab of a subfoveal choroidal neovascularisation (CNV) associated with pattern dystrophy in 1 patient Patients and methods: 4 affected and 3 unaffected patients (3 female 4 male, age range: 19 - 80 years) were assessed with a complete ophthalmologic examination. AF images were taken using Heidelberg Retina Angiograph and the digital color photos, fluorescein angiogragraphy (FFA) using the same TOPCON 501 camera. Electroretinogram (full-field and multifocal) was performed in 1 affected patient. One 48 years old patient developed a subfoveal CNV, which was treated with 2 injections of ranibizumab, at 3 months interval. Blood sample was taken for molecular analysis (screening of the gene RDS). Results: Two patients had a typical fundoscopic appearance of pattern dystrophy with butterfly shaped deposit at the fovea and some peripheral flecks, as shown with AF imaging.. Two others affected patients had a more unusual appearance with some macular atrophy in one or both eyes, surrounded by flecks. The visual acuity ranged from 1.0 to 0.1 according to Snellen EDTRS chart. The patient with subfoveal CNV presented a drop of vision form 1.0 to 0.6 within 10 days prior to the diagnosis and also reported some metamorphopsia. FFA and optical computerized tomography (OCT) confirmed a classic CNV. After the 1st injection her vision improved to 1.0 but persistent metamorphopsia and fluid on OCT motivated a second injection. One month after the second injection the OCT was flat and the patient had no symptoms. The results of RDS screening will be presented at the meeting. Conclusion: We present a family with pattern dystrophy, with some members having an unusual fundus appearance, which was mistaken for an early onset dry AMD. The AF imaging is a useful tool in diagnosing this condition. A CNV associated with pattern dystrophy a rare. This is the first report of a successful treatment of the CNV with anti-VEGF intravitreal injections.

Redirecting anti-viral CTL against cancer cells by surface targeting of monomeric MHC class I-viral peptide conjugated to antibody fragments.

To combine the advantage of both the tumor targeting capacity of high affinity monoclonal antibodies (mAbs) and the potent killing properties of cytotoxic T lymphocytes (CTL), we investigated the activity of conjugates made by coupling single Fab' fragments, from mAbs specific for tumor cell surface antigens, to monomeric HLA-A2 complexes containing the immunodominant influenza-matrix peptide 58-66. In solution, the monovalent 95 kDa Fab-HLA-A2/Flu conjugates did not activate influenza-specific CTL. However, when targeted to tumor cells expressing the relevant tumor-associated antigen, the conjugates induced CTL activation and efficient tumor cell lysis, as a result of MHC/peptide surface oligomerization. The highly specific and sensitive in vitro cytotoxicity results presented suggest that injection of Fab-MHC/peptide conjugates could represent a new form of immunotherapy, bridging antibody and T lymphocyte attack on cancer cells.

Ocular distribution, spectrum of activity, and in vivo viral neutralization of a fully humanized anti-herpes simplex virus IgG Fab fragment following topical application.

Herpes simplex ocular infection is a major cause of corneal blindness. Local antiviral treatments exist but are associated with corneal toxicity, and resistance has become an issue. We evaluated the biodistribution and efficacy of a humanized anti-herpes simplex virus (anti-HSV) IgG FAb fragment (AC-8; 53 kDa) following repeated topical administration. AC-8 was found in the corneal epithelium, anterior stroma, subepithelial stromal cells, and retinal glial cells, with preferential entry through the ocular limbus. AC-8 was active against 13 different strains of HSV-1, with 50% and 90% mean effective concentrations (MEC(50) and MEC(90), respectively) ranging from 0.03 to 0.13 μg/ml, indicating broad-spectrum activity. The in vivo efficacy of AC-8 was evaluated in a mouse model of herpes-induced ocular disease. Treatment with low-dose AC-8 (1 mg/ml) slightly reduced the ocular disease scores. A greater reduction of the disease scores was observed in the 10-mg/ml AC-8-treated group, but not as much as with trifluridine (TFT). AC-8 treatment reduced viral titers but less than trifluridine. AC-8 did not display any toxicity to the cornea or other structures in the eye. In summary, topical instillation of an anti-HSV FAb can be used on both intact and ulcerated corneas. It is well tolerated and does not alter reepithelialization. Further studies to improve the antiviral effect are needed for AC-8 to be considered for therapeutic use.

Down-regulation of NOSII gene expression by iontophoresis of anti-sense oligonucleotide in endotoxin-induced uveitis.

Transcorneoscleral iontophoresis was used to enhance ocular penetration of a 21-bp NH(2) protected anti-NOSII oligonucleotides (ODNs) (fluorescein or infrared-41 labeled) in Lewis rats. Both histochemical localization and acrylamide sequencing gels were used. To evaluate the potential to down-regulate NOSII expression in the rat model of endotoxin-induced uveitis (EIU), anti-sense NOSII ODN, scrambled ODN or saline were iontophorezed into these animals' eyes. Iontophoresis facilitated the penetration of intact ODNs into the intraocular tissues of the rat eye and only the eyes receiving ODNs and electrical current demonstrated intact ODNs within the ocular tissues of both segments of the eye. Iontophoresis of anti-NOSII ODN significantly down-regulated the expression of NOSII expression in iris/ciliary body compared to the saline or scrambled ODN treated eyes. Nitrite production was also significantly reduced in the anti-NOSII applied eyes compared to those treated with saline. Using this system, intraocular delivery of ODNs can be significantly enhanced increasing the potential for successful gene therapy for human eye diseases.

Anti-basal ganglia antibodies and Tourette's syndrome: a voxel-based morphometry and diffusion tensor imaging study in an adult population.

Anti-basal ganglia antibodies (ABGAs) have been suggested to be a hallmark of autoimmunity in Gilles de la Tourette's syndrome (GTS), possibly related to prior exposure to streptococcal infection. In order to detect whether the presence of ABGAs was associated with subtle structural changes in GTS, whole-brain analysis using independent sets of T(1) and diffusion tensor imaging MRI-based methods were performed on 22 adults with GTS with (n = 9) and without (n = 13) detectable ABGAs in the serum. Voxel-based morphometry analysis failed to detect any significant difference in grey matter density between ABGA-positive and ABGA-negative groups in caudate nuclei, putamina, thalami and frontal lobes. These results suggest that ABGA synthesis is not related to structural changes in grey and white matter (detectable with these methods) within frontostriatal circuits.

Evaluation of the anti-arenaviral activity of the subtilisin kexin isozyme-1/site-1 protease inhibitor PF-429242.

The cellular protease subtilisin kexin isozyme-1 (SKI-1)/site-1 protease (S1P) is implicated in the proteolytic processing of the viral envelope glycoprotein precursor (GPC) of arenaviruses, a step strictly required for production of infectious progeny. The small molecule SKI-1/S1P inhibitor PF-429242 was shown to have anti-viral activity against Old World arenaviruses. Here we extended these studies and show that PF-429242 also inhibits GPC processing and productive infection of New World arenaviruses, making PF-429242 a broadly active anti-arenaviral drug. In combination therapy, PF-429242 potentiated the anti-viral activity of ribavirin, indicating a synergism between the two drugs. A hallmark of arenaviruses is their ability to establish persistent infection in vitro and in vivo. Notably, PF-429242 was able to efficiently and rapidly clear persistent infection by arenaviruses. Interruption of drug treatment did not result in re-emergence of infection, indicating that PF-429242 treatment leads to virus extinction.

Visualizing anti-tumor immune responses in vivo.

Real-time imaging of stromal and immune cells in tumors is an emerging field that will greatly help us to understand the role of these non-malignant tumor components in tumor progression and therapy.