BackgroundInfection with dengue virus (DENV) may cause life-threatening disease with thrombocytopenia and vascular leakage which are related to dysfunction of platelets and endothelial cells. We previously showed that antibodies (Abs) against DENV nonstructural protein 1 (NS1) cross-react with human platelets and endothelial cells, leading to functional disturbances. Based on sequence homology analysis, the C-terminal region of DENV NS1 protein contains cross-reactive epitopes. For safety in vaccine development, the cross-reactive epitopes of DENV NS1 protein should be deleted or modified.Methodology/Principal FindingsWe tested the protective effects of Abs against full-length DENV NS1, NS1 lacking the C-terminal amino acids (a.a.) 271-352 (designated ΔC NS1), and chimeric DJ NS1 consisting of N-terminal DENV NS1 (a.a. 1-270) and C-terminal Japanese encephalitis virus NS1 (a.a. 271-352). The anti-ΔC NS1 and anti-DJ NS1 Abs showed a lower binding activity to endothelial cells and platelets than that of anti-DENV NS1 Abs. Passive immunization with anti-ΔC NS1 and anti-DJ NS1 Abs reduced DENV-induced prolonged mouse tail bleeding time. Treatment with anti-DENV NS1, anti-ΔC NS1 and anti-DJ NS1 Abs reduced local skin hemorrhage, controlled the viral load of DENV infection in vivo, synergized with complement to inhibit viral replication in vitro, as well as abolished DENV-induced macrophage infiltration to the site of skin inoculation. Moreover, active immunization with modified NS1 protein, but not with unmodified DENV NS1 protein, reduced DENV-induced prolonged bleeding time, local skin hemorrhage, and viral load.Conclusions/SignificanceThese results support the idea that modified NS1 proteins may represent an improved strategy for safe and effective vaccine development against DENV infection.

A rapid and sensitive reversed-phase high performance liquid chromatographic method for the quantitation of five furanocoumarins (bergaptol, psoralen, bergapten, 6',7'-dihydroxybergamottin, and bergamottin) is developed and validated. HPLC analysis of these five furanocoumarins is performed on a reversed-phase Inertsil ODS-2 column with a particle size of 5 microm. Using only water and acetonitrile as solvents, good separation, good precision, and high accuracy are obtained for the analysis of furanocoumarin components. This method is validated and applied to analyze the composition of five furanocoumarins in four citrus fruit juices (grapefruit, pomelo I, pomelo II, and shaddock) and ten Chinese herbal medicines (Bai-Zhi, Qiang-Huo, Du-Huo, Fang-Feng, Dang-Gui, Huang-Qin, Gan-Cao, Chen-Pi, Ge-Gen, and Yin-Chen-Hao) prepared by water decoction or an alcohol infusion. Results show that four of the five furanocoumarins (but not bergapten) are detected in grapefruit, pomelo I, and pomelo II, and the highest amount of these components is found in grapefruit juice. In the ten Chinese herbal medicines, the five furanocoumarins are not detected in Ge-Gen or Yin-Chen-Hao. The remaining herbs contain various compositions and amounts of furanocoumarins. In general, Chinese herbal medicines prepared by the 40% ethanol infusion contain larger amounts of furanocoumarins than those prepared by hot water decoction.

A 57‐year‐old man was diagnosed with chronic lymphocytic leukemia (CLL) during routine hematologic evaluation. Two months later, the patient developed a mildly pruritic periorbital eruption and erythematous plaques in a photosensitive distribution. A skin biopsy at an outside institution showed nonspecific histopathologic changes. The patient was diagnosed with amyopathic dermatomyositis and treated with prednisone 1 mg/kg/day with no improvement. The patient was subsequently admitted to our institution for CLL chemotherapy. Physical examination on admission revealed bilateral, violaceous, nonblanching periorbital plaques (Fig. 1A)and symmetric erythematous plaques with mottled hypo‐ and hyperpigmentation on the shoulders, proximal arms (Fig. 1B), and upper chest (Fig. 1C). Periungual erythema was noted. Muscle strength was normal. Laboratory examination was significant for a white cell count of 33,700/mm3 with 78% lymphocytes, a hematocrit of 25.8%, and a platelet count of 25,000/mm3. The lymphocytes were almost exclusively CD4 T cells expressing CD2, CD3, CD5, and CD7. Electrolytes, liver function tests, creatine kinase, aldolase, antinuclear antibodies, and anti‐Jo antibodies were normal or negative. Several biopsies of the plaques on the arms were obtained. Histopathology revealed leukemic infiltration of the skin with monoclonal T lymphocytes positive for CD2, CD3, CD4, CD5, and CD7 ( Fig. 2). Steroids were discontinued. The patient died a week later from toxic epidermal necrolysis secondary to allopurinol. 1 Clinical findings included periorbital violaceous plaques mimicking a heliotrope eruption (a) and poikilodermatous‐appearing plaques on the lateral arms (b) and upper chest (c) 2 Histopathology of a biopsy from the arm revealing dense dermal leukemic infiltrates with periadnexal accentuation

An attempt was made in this study to predict the potential for metabolic interactions of herbal extracts of drugs from their chromatographic profiles in reverse-phase high-performance liquid chromatography (RP-HPLC). Twenty-nine structurally related furanocoumarin compounds with known inhibitory interactions with cytochrome P450 3A (CYP3A), which is important for phase-I drug metabolism, were selected as a model system. A sigmoidal relationship was established between the CYP3A inhibitory potency (y) and the RP-HPLC total peak response unit (R(u), x) as y = 85.36 x (14.86 + x)⁻¹ with a correlation coefficient of 0.63. The sigmoidal curve could be divided into three ranges designated low, medium and high risk that were used to indicate the relative inhibitory potency of the metabolic interactions of herbs or traditional Chinese herb medicines with CYP3A. These predictive classifications provide information or might be useful for 'risk category' decisions concerning herb-drug interactions.