A Live Attenuated Chimeric West Nile Virus Vaccine, rWN/DEN4Δ30, Is Well Tolerated and Immunogenic in Flavivirus-Naive Older Adult Volunteers.

West Nile virus (WNV) is a major cause of mosquito-borne illness in the United States. Human disease ranges from mild febrile illness to severe fatal neurologic infection. Adults aged >60 years are more susceptible to neuroinvasive disease accompanied by a high mortality rate or long-lasting neurologic sequelae. A chimeric live attenuated West Nile virus vaccine, rWN/DEN4Δ30, was shown to be safe and immunogenic in healthy adults aged 18-50 years. This study evaluated rWN/DEN4Δ30 in flavivirus-naive adults aged 50-65 years and found it to be safe and immunogenic. Outbreaks of WNV infection tend to be unpredictable, and a safe and effective vaccine will be an important public health tool.

The live attenuated dengue vaccine TV003 elicits complete protection against dengue in a human challenge model.

A dengue human challenge model can be an important tool to identify candidate dengue vaccines that should be further evaluated in large efficacy trials in endemic areas. Dengue is responsible for about 390 million infections annually. Protective efficacy results for the most advanced dengue vaccine candidate (CYD) were disappointing despite its ability to induce neutralizing antibodies against all four dengue virus (DENV) serotypes. TV003 is a live attenuated tetravalent DENV vaccine currently in phase 2 evaluation. To better assess the protective efficacy of TV003, a randomized double-blind, placebo-controlled trial in which recipients of TV003 or placebo were challenged 6 months later with a DENV-2 strain, rDEN2Δ30, was conducted. The primary endpoint of the trial was protection against dengue infection, defined as rDEN2Δ30 viremia. Secondary endpoints were protection against rash and neutropenia. All 21 recipients of TV003 who were challenged with rDEN2Δ30 were protected from infection with rDEN2Δ30. None developed viremia, rash, or neutropenia after challenge. In contrast, 100% of the 20 placebo recipients who were challenged with rDEN2Δ30 developed viremia, 80% developed rash, and 20% developed neutropenia. TV003 induced complete protection against challenge with rDEN2Δ30 administered 6 months after vaccination. TV003 will be further evaluated in dengue-endemic areas. The controlled dengue human challenge model can accelerate vaccine development by evaluating the protection afforded by the vaccine, thereby eliminating poor candidates from further consideration before the initiation of large efficacy trials.

A retrospective evaluation of associations between chronic obstructive pulmonary disease, smoking, and efficacy of chemotherapy and selected laboratory parameters in patients with advanced non-small cell lung cancer.

AIM OF THE STUDY: To was to determine the impact of chronic obstructive pulmonary disease (COPD) and active smoking on the efficacy of chemotherapy and complete blood count (CBC) in patients with non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: The retrospective evaluation included 50 patients with stage IIIB-IV NSCLC, who started cisplatin-based chemotherapy. Peripheral blood CBC values were collected for testing before chemotherapy and after the first and third cycles. RESULTS: COPD was diagnosed in 49% of patients, while 42% of those enrolled were current smokers. Current smoking (p = 0.92) and COPD (p = 0.91) status did not affect the response to treatment. The non-COPD population presented a significantly higher pretreatment absolute lymphocyte count (ALC) than the COPD population (2.31 vs. 1.81 × 109/l; p = 0.0374). Also, only the non-COPD group demonstrated an elevated absolute monocyte count (AMC) following the first and third cycles of chemotherapy (p = 0.004). In current smokers, pretreatment values for white blood cells (WBC), absolute neutrophil count (ANC), and platelets (PLT) were higher than in the ex-smoker population (WBC 9.94 vs. 8.7 (× 109/l); p = 0.01; ANC 6.47 vs. 5.61 (× 109/l); p = 0.037; PLT 316 vs. 266 (× 109/l); p = 0.049). Ex-smokers demonstrated AMC level elevation after the first cycle of chemotherapy and PLT level elevation after the third cycle, while current smokers also demonstrated an early decrease in LMR. CONCLUSIONS: COPD and smoking induce chronic systemic inflammation and oxidative stress, which influence the results of standard laboratory tests, but do not change the response rate of lung cancer on chemotherapy.

Lipoprotein(A) with An Intact Lysine Binding Site Protects the Retina From an Age-Related Macular Degeneration Phenotype in Mice (An American Ophthalmological Society Thesis).

PURPOSE: To test the hypothesis that the accumulation of oxidized phospholipids (OxPL) in the macula is toxic to the retina unless neutralized by a variety of mechanisms, including binding by lipoprotein(a) [Lp(a)], which is composed of apolipoprotein(a) [apo(a)] and apolipoprotein B-100 (apoB). METHODS: Human maculas and eyes from two Lp(a) transgenic murine models were subjected to morphologic, ultrastructural, and immunohistochemical analysis. "Wild-type Lp(a)" mice, which express human apoB-100 and apo(a) that contains oxidized phospholipid, and "mutant LBS(-) Lp(a)" mice with a defective apo(a) lysine binding site (LBS) for oxidized phospholipid binding, were fed a chow or high-fat diet for 2 to 12 months. Oxidized phospholipid-containing lipoproteins were detected by immunoreactivity to E06, a murine monoclonal antibody binding to the phosphocholine headgroup of oxidized, but not native, phospholipids. RESULTS: Oxidized phospholipids, apo(a), and apoB accumulate in maculas, including drusen, of age-related macular degeneration (AMD) samples and age-matched controls. Lp(a) mice fed a high-fat diet developed age-related changes. However, mutant LBS(-) Lp(a) mice fed a high-fat diet developed retinal pigment epithelial cell degeneration and drusen. These changes were associated with increased OxPL, decreased antioxidant defenses, increased complement, and decreased complement regulators. CONCLUSIONS: Human maculas accumulate Lp(a) and OxPL. Mutant LBS(-) Lp(a) mice, lacking the ability to bind E06-detectable oxidized phospholipid, develop AMD-like changes. The ability of Lp(a) to bind E06-detectable OxPL may play a protective role in AMD.

Tamoxifen-induced acute pancreatitis - a case report.

Tamoxifen is a selective estrogen receptor modulator used for the treatment of oestrogen/progesterone receptor positive breast cancer. It has antagonistic or agonistic activity depending on the tissue location. Generally it causes mild and reversible side effects, however more serious ones including cardiovascular and thromboembolic adverse events, uterine cancer or acute pancreatitis can also occur. Tamoxifen, like oestrogens, increases the plasma level of TG and liver secretion of VLDL. Moreover, it inhibits the key enzymes of triglyceride metabolism. In this report we present a case of a 55-year-old woman with a history of a poorly controlled hypertriglyceridaemia diagnosed with breast cancer. She was treated with surgery and adjuvant chemotherapy, radiotherapy and hormonotherapy with tamoxifen. About three months after hormonal treatment, her triglyceride level increased. Five months later she developed an acute necrotic pancreatitis that required hospitalization. Her serum samples on admission were highly lipemic. An abdominal ultrasound showed no evidence of gallstones or dilation of the bile ducts. There was no history of alcohol abuse or abdominal trauma. Tamoxifen was suspected as a trigger factor for pancreatitis. After the drug withdrawal and administration of the conservative management the patient's medical condition improved. Due to a postmenopausal status of the patient and no harmful effect on serum lipids, an adjuvant hormonotherapy with aromatase inhibitor was started.

Cell surface transglutaminase promotes RhoA activation via integrin clustering and suppression of the Src-p190RhoGAP signaling pathway.

Tissue transglutaminase (tTG) is a multifunctional protein that serves as cross-linking enzyme and integrin-binding adhesion coreceptor for fibronectin on the cell surface. Previous work showed activation of small GTPase RhoA via enzymatic transamidation by cytoplasmic tTG. Here, we report an alternative nonenzymatic mechanism of RhoA activation by cell surface tTG. Direct engagement of surface tTG with specific antibody or the fibronectin fragment containing modules I(6)II(1,2)I(7-9) increases RhoA-GTP levels. Integrin-dependent signaling to RhoA and its downstream target Rho-associated coiled-coil containing serine/threonine protein kinase (ROCK) is amplified by surface tTG. tTG expression on the cell surface elevates RhoA-GTP levels in nonadherent and adherent cells, delays maximal RhoA activation upon cell adhesion to fibronectin and accelerates a rise in RhoA activity after binding soluble integrin ligands. These data indicate that surface tTG induces integrin clustering regardless of integrin-ligand interactions. This notion is supported by visualization of integrin clusters, increased susceptibility of integrins to chemical cross-linking, and biochemical detection of large integrin complexes in cells expressing tTG. In turn, integrin aggregation by surface tTG inhibits Src kinase activity and decreases activation of the Src substrate p190RhoGAP. Moreover, pharmacological inhibition of Src kinase reveals inactivation of Src signaling as the primary cause of elevated RhoA activity in cells expressing tTG. Together, these findings show that surface tTG amplifies integrin-mediated signaling to RhoA/ROCK via integrin clustering and down-regulation of the Src-p190RhoGAP regulatory pathway.

The role of tissue transglutaminase in cell-matrix interactions.

Numerous studies over the last two decades revealed a complexity and multiple functions of tissue transglutaminase (tTG or TG2, EC 2.3.2.13). Besides the ability to catalyze Ca2+-dependent transamidation of proteins and formation of protein polymers via protease-resistant covalent isopeptide bonds, tTG also possesses GTPase enzymatic activity which links this protein to certain intracellular signaling pathways. Moreover, in addition to cytoplasmic and nuclear localization, a significant part of the protein pool is present on the cell surface. A number of recent findings indicate that surface tTG is involved in the interactions of cells with the surrounding extracellular matrix (ECM). In this review we will focus on the newly defined non-enzymatic adhesive function of tTG in cell-matrix interactions and discuss contributions of previously characterized enzymatic activities of tTG to cell-matrix adhesion and adhesion-dependent processes. Understanding molecular interactions and enzymatic activities of tTG will gain further insights into the role of this protein in normal human physiology and various pathological conditions.

Effect of protease treatment on plasma infectivity in variant Creutzfeldt-Jakob disease mice.

BACKGROUND: The emergence of variant Creutzfeldt-Jakob disease (vCJD) and of a probable transmission of the disease through blood transfusion from a presymptomatic case has underlined the need for a reliable, sensitive, and specific screening test. This study was initiated to explain why attempts to identify protease-resistant prion protein (PrPres) following treatment with proteinase K (PK) in blood or blood components have so far failed. STUDY DESIGN AND METHODS: RIII mice were inoculated intracerebrally (i.c.) with vCJD agent. As soon as some mice became ill, blood from all mice was collected, pooled, and separated into components. Aliquots of plasma were treated with either 100 and 500 microg per mL PK or left untreated. Samples were analyzed for total protein and for PrPres by Western blot with 6H4 antibodies. Infectivity in PK-treated and untreated samples was bioassayed by i.c. inoculation into healthy mice. RESULTS: Estimated infectivity in untreated control plasma was 20.6 IU per mL. Treatment of plasma with 100 or 500 microg per mL PK resulted in estimated infectivity levels of 8.4 and 5.2 IU per mL, respectively. Coomassie staining revealed substantial changes in the protein profile after PK treatment, with massive degradation of proteins at 500 microg per mL PK. No PrPres was detected in plasma samples by Western blotting. CONCLUSION: Infectivity in plasma of vCJD-infected mice showed a trend toward reduction following enzymatic treatment with increasing doses of PK, possibly because of activity against proteolysis-sensitive isoforms of abnormal prion protein. It is concluded that the use of PK in protocols for the detection of PrPres may decrease the sensitivity of blood-based assays.